const express = require("express");
const cors = require("cors");
require("dotenv").config();

const db = require("./db");
const { authMiddleware } = require("./middleware");

const app = express();
app.use(express.json());
app.use(cors());

const ERROR_LOG_API_URL =
  process.env.ERROR_LOG_API_URL ||
  "https://error.xtransit.testinstance.nl/error_log";

function isValidDateKey(value) {
  if (!/^\d{4}-\d{2}-\d{2}$/.test(String(value || ""))) return false;
  const date = new Date(`${value}T00:00:00Z`);
  return (
    !Number.isNaN(date.getTime()) && date.toISOString().slice(0, 10) === value
  );
}

function friendlyErrorMessage(statusCode) {
  if (statusCode === 400) return "Controleer je invoer en probeer opnieuw.";
  if (statusCode === 401) return "Je sessie is verlopen. Log opnieuw in.";
  if (statusCode === 403) return "Je hebt hier geen toegang toe.";
  if (statusCode === 404) return "Niet gevonden.";
  return "Er ging iets mis. Probeer het later opnieuw.";
}

async function reportError({ partofservice, error }) {
  try {
    await fetch(ERROR_LOG_API_URL, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        service: "transit_api",
        partofservice,
        error,
      }),
    });
  } catch (_) {}
}

app.use((req, res, next) => {
  const originalJson = res.json.bind(res);
  res.json = (body) => {
    if (res.statusCode >= 400 && body && typeof body === "object") {
      const rawError =
        body.error || body.message || body.details || `HTTP ${res.statusCode}`;
      void reportError({
        partofservice: `${req.method} ${req.originalUrl}`,
        error: rawError,
      });
      return originalJson({ error: friendlyErrorMessage(res.statusCode) });
    }
    return originalJson(body);
  };

  next();
});

app.get("/health", async (_req, res) => {
  try {
    await db.query("SELECT 1");
    res.json({ status: "ok", service: "transit_api", database: "ok" });
  } catch (err) {
    console.error("GET /health error:", err);
    res.status(503).json({ status: "unavailable", service: "transit_api" });
  }
});

// Development mock storage when DEV_MOCK=1
const DEV_MOCK = process.env.DEV_MOCK === "1";
const _mock = {
  stops: [],
  routeStops: [],
  busLines: [],
  fleetBuses: [],
  schedules: [],
  scheduleStopProgress: [],
  drivers: [],
  nextStopId: 1,
  nextRouteStopId: 1,
  nextBusLineId: 1,
  nextFleetBusId: 1,
  nextScheduleId: 1,
  nextScheduleStopProgressId: 1,
  nextDriverId: 1,
};

// Initialize mock drivers
if (DEV_MOCK) {
  _mock.drivers = [
    {
      id: 1,
      name: "Jan Peterse",
      email: "jan@transit.local",
      phone: "06-12345678",
      status: "active",
    },
    {
      id: 2,
      name: "Maria Kuijpers",
      email: "maria@transit.local",
      phone: "06-87654321",
      status: "active",
    },
    {
      id: 3,
      name: "Robert Smits",
      email: "robert@transit.local",
      phone: "06-55555555",
      status: "active",
    },
    {
      id: 4,
      name: "Anja Voorn",
      email: "anja@transit.local",
      phone: "06-44444444",
      status: "inactive",
    },
  ];
  _mock.nextDriverId = 5;

  // Initialize test bus lines
  _mock.busLines = [
    {
      id: 1,
      lineNumber: 1,
      startStop: "Central Station",
      endStop: "Airport",
      estimatedDurationMinutes: 45,
      description: "Main route",
    },
    {
      id: 2,
      lineNumber: 2,
      startStop: "Central Station",
      endStop: "Harbor",
      estimatedDurationMinutes: 30,
      description: "Harbor route",
    },
  ];
  _mock.nextBusLineId = 3;

  // Initialize test stops
  _mock.stops = [
    {
      id: 1,
      name: "Central Station",
      latitude: 52.0116,
      longitude: 4.7055,
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    },
    {
      id: 2,
      name: "City Center",
      latitude: 52.0125,
      longitude: 4.71,
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    },
    {
      id: 3,
      name: "Airport",
      latitude: 52.03,
      longitude: 4.75,
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    },
  ];
  _mock.nextStopId = 4;

  // Initialize test route stops
  _mock.routeStops = [
    {
      id: 1,
      busLineId: 1,
      stopId: 1,
      stopOrder: 1,
      estimatedArrivalMinutes: 0,
      name: "Central Station",
      latitude: 52.0116,
      longitude: 4.7055,
    },
    {
      id: 2,
      busLineId: 1,
      stopId: 2,
      stopOrder: 2,
      estimatedArrivalMinutes: 15,
      name: "City Center",
      latitude: 52.0125,
      longitude: 4.71,
    },
    {
      id: 3,
      busLineId: 1,
      stopId: 3,
      stopOrder: 3,
      estimatedArrivalMinutes: 45,
      name: "Airport",
      latitude: 52.03,
      longitude: 4.75,
    },
  ];
  _mock.nextRouteStopId = 4;

  // Initialize test fleet buses
  _mock.fleetBuses = [
    {
      id: 1,
      name: "Bus 101",
      seatCapacity: 45,
      licensePlate: "AB-01-CD",
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    },
    {
      id: 2,
      name: "Bus 102",
      seatCapacity: 50,
      licensePlate: "AB-02-CD",
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    },
  ];
  _mock.nextFleetBusId = 3;

  // Initialize test schedule
  const now = new Date();
  const tomorrow = new Date(now.getTime() + 24 * 60 * 60 * 1000);
  tomorrow.setHours(10, 0, 0, 0);
  const endTime = new Date(tomorrow.getTime() + 45 * 60 * 1000);

  _mock.schedules = [
    {
      id: 1,
      busLineId: 1,
      busId: 1,
      driverId: null,
      startTime: tomorrow.toISOString(),
      endTime: endTime.toISOString(),
      weekdays: [],
      status: "planned",
      createdAt: new Date().toISOString(),
    },
  ];
  _mock.nextScheduleId = 2;
}

const adminMiddleware = (req, res, next) => {
  if (!req.user || !req.user.isAdmin) {
    return res.status(403).json({ error: "forbidden" });
  }

  next();
};

// ============================================
// HELPER FUNCTIONS
// ============================================

/**
 * Calculate departure times for each stop in a route
 * Returns array of { order, stopName, departureTime }
 */
function calculateDepartureTimes(startTime, busLineId, mock) {
  const startDate = new Date(startTime);

  // Get route stops for this bus line
  const routeStops = mock.routeStops
    .filter((rs) => rs.busLineId === busLineId)
    .sort((a, b) => a.stopOrder - b.stopOrder);

  return routeStops.map((rs) => {
    const departureDate = new Date(startDate);
    // Add estimated arrival minutes to get departure time
    departureDate.setMinutes(
      departureDate.getMinutes() + (rs.estimatedArrivalMinutes || 0),
    );

    const stop = mock.stops.find((s) => s.id === rs.stopId);
    return {
      order: rs.stopOrder,
      stopId: rs.stopId,
      stopName: stop?.name || "Unknown Stop",
      estimatedArrivalMinutes: rs.estimatedArrivalMinutes || 0,
      departureTime: departureDate.toISOString(),
    };
  });
}

function parseWeekdaysValue(value) {
  if (!value) return [];
  if (Array.isArray(value))
    return value.map((v) => Number(v)).filter((v) => Number.isFinite(v));

  if (typeof value === "string") {
    const trimmed = value.trim();
    if (!trimmed) return [];

    try {
      const parsed = JSON.parse(trimmed);
      if (Array.isArray(parsed)) {
        return parsed.map((v) => Number(v)).filter((v) => Number.isFinite(v));
      }
    } catch (_) {
      // Fall through to CSV/PG-array parsing.
    }

    // Handles values like "1,2,3" or "{1,2,3}".
    const normalized = trimmed.replace("{", "").replace("}", "");
    return normalized
      .split(",")
      .map((v) => Number(v.trim()))
      .filter((v) => Number.isFinite(v));
  }

  return [];
}

function toNumberOrNull(value) {
  if (value === undefined || value === null || value === "") return null;
  const numberValue = Number(value);
  return Number.isFinite(numberValue) ? numberValue : null;
}

function parseCommaSeparatedValues(value) {
  if (!value && value !== 0) return [];
  if (Array.isArray(value)) {
    return value.map((item) => String(item).trim()).filter(Boolean);
  }

  return String(value)
    .split(",")
    .map((item) => item.trim())
    .filter(Boolean);
}

function toDateKey(value) {
  if (!value) return null;
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return null;
  return date.toISOString().slice(0, 10);
}

function expandRecurringScheduleRows(rows) {
  const expandedRows = [];

  for (const row of rows) {
    const weekdays = parseWeekdaysValue(row.weekdays);
    if (!weekdays || weekdays.length === 0) {
      expandedRows.push(row);
      continue;
    }

    const templateDate = new Date(row.start_time);
    if (Number.isNaN(templateDate.getTime())) {
      expandedRows.push(row);
      continue;
    }

    const templateDayOfWeek = templateDate.getDay();
    const sortedWeekdays = [...new Set(weekdays)].sort((a, b) => a - b);
    const durationMinutes = Number(
      row.estimated_duration_minutes ?? row.estimatedDurationMinutes ?? 60,
    );

    for (let week = 0; week < 52; week++) {
      for (const targetWeekday of sortedWeekdays) {
        const daysOffset = (targetWeekday - templateDayOfWeek + 7) % 7;
        const totalDays = week * 7 + daysOffset;

        const scheduleDate = new Date(templateDate);
        scheduleDate.setDate(scheduleDate.getDate() + totalDays);

        const endDate = new Date(scheduleDate);
        endDate.setMinutes(endDate.getMinutes() + durationMinutes);

        expandedRows.push({
          ...row,
          start_time: scheduleDate.toISOString(),
          end_time: endDate.toISOString(),
          is_recurring_instance: true,
          template_id: row.id,
        });
      }
    }
  }

  return expandedRows;
}

function mapAdminScheduleRow(row, routeStopsByLine = new Map()) {
  const weekdays = parseWeekdaysValue(row.weekdays);
  const busLineId = Number(row.busLineId ?? row.bus_line_id);
  const startTime = row.startTime ?? row.start_time;
  const routeStops = routeStopsByLine.get(busLineId) || [];
  const departureTimes = buildDepartureTimes(startTime, routeStops);

  return {
    id: Number(row.id),
    busLineId,
    busId: Number(row.busId ?? row.bus_id),
    driverId:
      row.driverId !== null && row.driverId !== undefined
        ? Number(row.driverId)
        : null,
    driverName: row.driverName ?? row.driver_name ?? null,
    startTime,
    endTime: row.endTime ?? row.end_time,
    weekdays,
    departureTimes,
    status: row.status,
    lineNumber: Number(row.lineNumber ?? row.line_number) || null,
    busName: row.busName ?? row.bus_name ?? "Unknown Bus",
    licensePlate: row.licensePlate ?? row.license_plate ?? null,
    createdAt: row.createdAt ?? row.created_at ?? null,
    isRecurringInstance: row.is_recurring_instance || false,
    templateId: row.template_id || row.templateId || null,
    recurrenceLabel: formatWeekdayLabel(weekdays),
    isRecurring: weekdays.length > 0,
  };
}

function scheduleMatchesFilters(
  schedule,
  filters,
  routeStopsByLine = new Map(),
) {
  if (!schedule || !filters) return true;

  const scheduleBusLineId = Number(schedule.bus_line_id ?? schedule.busLineId);
  const scheduleBusId = Number(schedule.bus_id ?? schedule.busId);
  const scheduleDriverId = Number(schedule.driver_id ?? schedule.driverId);
  const scheduleStatus = String(schedule.status || "");
  const scheduleDateKey = toDateKey(schedule.start_time ?? schedule.startTime);

  if (filters.busLineId !== null && scheduleBusLineId !== filters.busLineId) {
    return false;
  }

  if (filters.busId !== null && scheduleBusId !== filters.busId) {
    return false;
  }

  if (filters.driverId !== null && scheduleDriverId !== filters.driverId) {
    return false;
  }

  if (
    filters.statuses.length > 0 &&
    !filters.statuses.includes(scheduleStatus)
  ) {
    return false;
  }

  if (filters.date && scheduleDateKey !== filters.date) {
    return false;
  }

  if (
    filters.fromDate &&
    scheduleDateKey &&
    scheduleDateKey < filters.fromDate
  ) {
    return false;
  }

  if (filters.toDate && scheduleDateKey && scheduleDateKey > filters.toDate) {
    return false;
  }

  if (filters.stopId !== null) {
    const routeStops = routeStopsByLine.get(scheduleBusLineId) || [];
    const matchesStop = routeStops.some(
      (routeStop) =>
        Number(routeStop.stop_id ?? routeStop.stopId) === filters.stopId,
    );
    if (!matchesStop) {
      return false;
    }
  }

  return true;
}

function parseScheduleFilters(query, options = {}) {
  const statuses = parseCommaSeparatedValues(
    query.status || query.statuses || options.statuses || [],
  );

  return {
    date: query.date ? String(query.date).trim() : null,
    fromDate: query.fromDate ? String(query.fromDate).trim() : null,
    toDate: query.toDate ? String(query.toDate).trim() : null,
    driverId: toNumberOrNull(
      query.driverId ??
        query.driver_id ??
        query.chauffeurId ??
        query.chauffeur_id,
    ),
    busId: toNumberOrNull(query.busId ?? query.bus_id),
    busLineId: toNumberOrNull(
      query.busLineId ?? query.lineId ?? query.bus_line_id,
    ),
    stopId: toNumberOrNull(
      query.stopId ?? query.stop_id ?? query.busStopId ?? query.bus_stop_id,
    ),
    statuses,
  };
}

function formatWeekdayLabel(weekdays) {
  const labels = ["Zo", "Ma", "Di", "Wo", "Do", "Vr", "Za"];

  if (!Array.isArray(weekdays) || weekdays.length === 0) {
    return "Eenmalig";
  }

  if (weekdays.length === 7) {
    return "Dagelijks";
  }

  return [...new Set(weekdays)]
    .sort((a, b) => a - b)
    .filter((day) => day >= 0 && day < labels.length)
    .map((day) => labels[day])
    .join(", ");
}

function buildDepartureTimes(startTime, routeStops = []) {
  const startDate = new Date(startTime);

  return routeStops.map((routeStop) => {
    const departureDate = new Date(startDate);
    const etaMinutes =
      Number(
        routeStop.estimated_arrival_minutes ??
          routeStop.estimatedArrivalMinutes,
      ) || 0;
    departureDate.setMinutes(departureDate.getMinutes() + etaMinutes);

    return {
      order: Number(routeStop.stop_order ?? routeStop.stopOrder),
      stopId: Number(routeStop.stop_id ?? routeStop.stopId),
      stopName: routeStop.stop_name || routeStop.name || "Unknown Stop",
      estimatedArrivalMinutes: etaMinutes,
      departureTime: departureDate.toISOString(),
    };
  });
}

function isRecurringSchedule(schedule) {
  return parseWeekdaysValue(schedule.weekdays).length > 0;
}

function scheduleOccursOnDate(schedule, dateKey) {
  if (!dateKey) return true;

  const weekdays = parseWeekdaysValue(schedule.weekdays);
  const scheduleDateKey = toDateKey(schedule.start_time ?? schedule.startTime);

  if (!scheduleDateKey) {
    return false;
  }

  if (weekdays.length === 0) {
    return scheduleDateKey === dateKey;
  }

  if (scheduleDateKey > dateKey) {
    return false;
  }

  const targetDate = new Date(`${dateKey}T00:00:00`);
  return weekdays.includes(targetDate.getDay());
}

function materializeScheduleOverviewRow(
  row,
  dateKey,
  routeStopsByLine = new Map(),
) {
  const weekdays = parseWeekdaysValue(row.weekdays);
  const recurring = weekdays.length > 0;
  const templateStart = new Date(row.startTime ?? row.start_time);
  const templateEnd = new Date(row.endTime ?? row.end_time);
  let startTime = row.startTime ?? row.start_time;
  let endTime = row.endTime ?? row.end_time;

  if (recurring && dateKey) {
    const occurrenceStart = new Date(`${dateKey}T00:00:00`);
    occurrenceStart.setHours(
      templateStart.getHours(),
      templateStart.getMinutes(),
      templateStart.getSeconds(),
      templateStart.getMilliseconds(),
    );

    startTime = occurrenceStart.toISOString();

    if (
      Number.isFinite(templateEnd.getTime()) &&
      Number.isFinite(templateStart.getTime())
    ) {
      const durationMillis = templateEnd.getTime() - templateStart.getTime();
      const occurrenceEnd = new Date(occurrenceStart);
      occurrenceEnd.setMilliseconds(
        occurrenceEnd.getMilliseconds() + durationMillis,
      );
      endTime = occurrenceEnd.toISOString();
    }
  }

  const busLineId = Number(row.busLineId ?? row.bus_line_id);
  const routeStops = routeStopsByLine.get(busLineId) || [];
  const departureTimes = buildDepartureTimes(startTime, routeStops);

  return {
    id: Number(row.id),
    busLineId,
    busId: Number(row.busId ?? row.bus_id),
    // Hide driver information in public schedule materialization for privacy
    driverId: null,
    driverName: null,
    startTime,
    endTime,
    weekdays,
    status: row.status,
    lineNumber: Number(row.lineNumber ?? row.line_number) || null,
    busName: row.busName ?? row.bus_name ?? "Unknown Bus",
    licensePlate: row.licensePlate ?? row.license_plate ?? null,
    createdAt: row.createdAt ?? row.created_at ?? null,
    scheduleType: recurring ? "recurring" : "one_time",
    recurrenceLabel: formatWeekdayLabel(weekdays),
    isRecurringInstance: recurring && Boolean(dateKey),
    templateId: row.templateId ?? row.template_id ?? null,
    departureTimes,
  };
}

function mapRecurringOccurrenceRows(rows, dateKey, routeStopsByLine) {
  return rows
    .filter((row) => scheduleOccursOnDate(row, dateKey))
    .map((row) =>
      materializeScheduleOverviewRow(row, dateKey, routeStopsByLine),
    )
    .sort((a, b) => new Date(a.startTime) - new Date(b.startTime));
}

function materializeScheduleRowsInRange(
  rows,
  fromDateKey,
  toDateKey,
  routeStopsByLine,
) {
  const occurrences = [];
  if (!fromDateKey || !toDateKey) return occurrences;

  const fromDate = new Date(`${fromDateKey}T00:00:00`);
  const toDate = new Date(`${toDateKey}T23:59:59`);

  // Safety cap: don't generate more than 366 days
  const maxDays = 366;
  const spanDays = Math.ceil((toDate - fromDate) / (24 * 60 * 60 * 1000));
  if (spanDays > maxDays) return occurrences;

  for (const row of rows) {
    const weekdays = parseWeekdaysValue(row.weekdays);

    if (!weekdays || weekdays.length === 0) {
      const rowDateKey = toDateKey(row.start_time ?? row.startTime);
      if (rowDateKey && rowDateKey >= fromDateKey && rowDateKey <= toDateKey) {
        occurrences.push(
          materializeScheduleOverviewRow(row, rowDateKey, routeStopsByLine),
        );
      }
      continue;
    }

    // recurring template: generate occurrences per weekday within range
    const templateStart = new Date(row.start_time ?? row.startTime);
    for (const wd of [...new Set(weekdays)]) {
      // find first date >= fromDate that matches weekday wd and is >= templateStart
      let cursor = new Date(fromDate);
      const fromWeekday = cursor.getDay();
      const daysOffset = (wd - fromWeekday + 7) % 7;
      cursor.setDate(cursor.getDate() + daysOffset);

      // ensure cursor >= templateStart (so recurrence doesn't start before template)
      if (cursor < templateStart) {
        // advance by weeks until >= templateStart
        const diffDays = Math.ceil(
          (templateStart - cursor) / (24 * 60 * 60 * 1000),
        );
        const weeksToAdvance = Math.ceil(diffDays / 7);
        cursor.setDate(cursor.getDate() + weeksToAdvance * 7);
      }

      while (cursor <= toDate) {
        const occurrenceKey = cursor.toISOString().slice(0, 10);
        occurrences.push(
          materializeScheduleOverviewRow(row, occurrenceKey, routeStopsByLine),
        );
        cursor.setDate(cursor.getDate() + 7);
      }
    }
  }

  // sort and return
  return occurrences.sort(
    (a, b) => new Date(a.startTime) - new Date(b.startTime),
  );
}

/**
 * Check if two schedules have date/weekday overlap
 */
function doSchedulesDateOverlap(
  schedule1Start,
  schedule1End,
  schedule1Weekdays,
  schedule2Start,
  schedule2End,
  schedule2Weekdays,
) {
  const s1Start = new Date(schedule1Start);
  const s1End = new Date(schedule1End);
  const s2Start = new Date(schedule2Start);
  const s2End = new Date(schedule2End);

  // Check time overlap
  if (s1End <= s2Start || s2End <= s1Start) {
    return false; // No time overlap
  }

  // If both have no weekdays (one-time), check if same day
  if (
    (!schedule1Weekdays || schedule1Weekdays.length === 0) &&
    (!schedule2Weekdays || schedule2Weekdays.length === 0)
  ) {
    return s1Start.toDateString() === s2Start.toDateString();
  }

  // If one has weekdays and other doesn't, check if one-time falls on weekday
  if (
    schedule1Weekdays &&
    schedule1Weekdays.length > 0 &&
    (!schedule2Weekdays || schedule2Weekdays.length === 0)
  ) {
    const s2Day = s2Start.getDay(); // 0=Sun, 1=Mon, etc.
    const s2Adjusted = s2Day === 0 ? 0 : s2Day; // Normalize to 0-6
    return schedule1Weekdays.includes(s2Adjusted);
  }

  if (
    (!schedule1Weekdays || schedule1Weekdays.length === 0) &&
    schedule2Weekdays &&
    schedule2Weekdays.length > 0
  ) {
    const s1Day = s1Start.getDay();
    const s1Adjusted = s1Day === 0 ? 0 : s1Day;
    return schedule2Weekdays.includes(s1Adjusted);
  }

  // Both have weekdays: check if any day overlaps
  if (schedule1Weekdays && schedule2Weekdays) {
    return schedule1Weekdays.some((d) => schedule2Weekdays.includes(d));
  }

  return false;
}

/**
 * Check if a driver has conflicts with existing schedules
 */
function checkDriverConflict(
  driverId,
  startTime,
  endTime,
  weekdays,
  allSchedules,
  excludeScheduleId = null,
) {
  if (!driverId) return false; // No conflict if no driver specified

  return allSchedules.some((s) => {
    if (excludeScheduleId && s.id === excludeScheduleId) return false;
    const sDriverId = s.driverId ?? s.driver_id;
    if (Number(sDriverId) !== Number(driverId)) return false;

    const sWeekdays = parseWeekdaysValue(s.weekdays);
    const wkdays = weekdays || [];
    const sStart = s.startTime ?? s.start_time;
    const sEnd = s.endTime ?? s.end_time;

    return doSchedulesDateOverlap(
      startTime,
      endTime,
      wkdays,
      sStart,
      sEnd,
      sWeekdays,
    );
  });
}

/**
 * Check if a bus has conflicts with existing schedules
 */
function checkBusConflict(
  busId,
  startTime,
  endTime,
  weekdays,
  allSchedules,
  excludeScheduleId = null,
) {
  if (!busId) return false;

  return allSchedules.some((s) => {
    if (excludeScheduleId && s.id === excludeScheduleId) return false;
    const sBusId = s.busId ?? s.bus_id;
    if (Number(sBusId) !== Number(busId)) return false;

    const sWeekdays = parseWeekdaysValue(s.weekdays);
    const wkdays = weekdays || [];
    const sStart = s.startTime ?? s.start_time;
    const sEnd = s.endTime ?? s.end_time;

    return doSchedulesDateOverlap(
      startTime,
      endTime,
      wkdays,
      sStart,
      sEnd,
      sWeekdays,
    );
  });
}

async function ensureScheduleStopProgressTable() {
  if (DEV_MOCK) return;

  await db.query(`
    CREATE TABLE IF NOT EXISTS transit.schedule_stop_progress (
      id BIGSERIAL PRIMARY KEY,
      schedule_id INTEGER NOT NULL,
      bus_line_id INTEGER NOT NULL,
      stop_id INTEGER NOT NULL,
      stop_order INTEGER NOT NULL,
      stop_name TEXT,
      estimated_arrival_minutes INTEGER NOT NULL DEFAULT 0,
      scheduled_passed_at TIMESTAMPTZ NOT NULL,
      scheduled_passed_date DATE NOT NULL,
      actual_passed_at TIMESTAMPTZ NOT NULL,
      delay_minutes INTEGER NOT NULL DEFAULT 0,
      marked_by_user_id INTEGER,
      created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
      UNIQUE (schedule_id, stop_order, scheduled_passed_date)
    )
  `);

  await db.query(`
    ALTER TABLE transit.schedule_stop_progress
    ADD COLUMN IF NOT EXISTS scheduled_passed_date DATE
  `);

  await db.query(`
    UPDATE transit.schedule_stop_progress
    SET scheduled_passed_date = scheduled_passed_at::date
    WHERE scheduled_passed_date IS NULL
  `);

  await db.query(`
    ALTER TABLE transit.schedule_stop_progress
    ALTER COLUMN scheduled_passed_date SET NOT NULL
  `);

  await db.query(`
    DO $$
    DECLARE
      constraint_name text;
    BEGIN
      SELECT tc.constraint_name
      INTO constraint_name
      FROM information_schema.table_constraints tc
      JOIN information_schema.key_column_usage kcu
        ON tc.constraint_name = kcu.constraint_name
       AND tc.table_schema = kcu.table_schema
       AND tc.table_name = kcu.table_name
      WHERE tc.table_schema = 'transit'
        AND tc.table_name = 'schedule_stop_progress'
        AND tc.constraint_type = 'UNIQUE'
      GROUP BY tc.constraint_name
      HAVING array_agg(kcu.column_name ORDER BY kcu.ordinal_position)::text[] = ARRAY['schedule_id', 'stop_order']::text[]
      LIMIT 1;

      IF constraint_name IS NOT NULL THEN
        EXECUTE format('ALTER TABLE transit.schedule_stop_progress DROP CONSTRAINT %I', constraint_name);
      END IF;
    END $$;
  `);

  await db.query(`
    CREATE UNIQUE INDEX IF NOT EXISTS idx_schedule_stop_progress_schedule_order_date
    ON transit.schedule_stop_progress (schedule_id, stop_order, scheduled_passed_date)
  `);

  await db.query(`
    CREATE INDEX IF NOT EXISTS idx_schedule_stop_progress_schedule_order
    ON transit.schedule_stop_progress (schedule_id, stop_order, scheduled_passed_date)
  `);
}

// ============================================
// ROUTES - Get daily schedule
// ============================================
app.get("/schedule/daily", authMiddleware, async (req, res) => {
  try {
    const { date } = req.query;
    const userId = req.user.userId;

    if (!date) {
      return res.status(400).json({ error: "date query parameter required" });
    }

    const result = await db.query(
      `
      SELECT 
        r.id,
        r.start_time,
        r.end_time,
        r.status,
        bl.id as line_id,
        bl.line_number,
        bl.start_stop,
        bl.end_stop,
        bl.estimated_duration_minutes,
        bl.description,
        bt.id as bus_type_id,
        bt.name as bus_type,
        bt.seat_capacity,
        bt.license_plate
      FROM transit.routes r
      JOIN transit.bus_lines bl ON r.bus_line_id = bl.id
      JOIN fleet.bus bt ON r.bus_type_id = bt.id
      WHERE r.user_id = $1 AND DATE(r.start_time) = $2
      ORDER BY r.start_time ASC
    `,
      [userId, date],
    );

    let routes = result.rows.map((row) => ({
      id: row.id,
      startTime: row.start_time,
      endTime: row.end_time,
      status: row.status,
      busLine: {
        id: row.line_id,
        lineNumber: row.line_number,
        startStop: row.start_stop,
        endStop: row.end_stop,
        estimatedDuration: row.estimated_duration_minutes,
        description: row.description,
      },
      busType: {
        id: row.bus_type_id,
        name: row.bus_type,
        seatCapacity: row.seat_capacity,
        licensePlate: row.license_plate,
      },
    }));

    // If no explicit "routes" rows exist for this user/date, fall back to
    // checking scheduled runs in `transit.schedules` (filtered by driver_id).
    // This works around cases where DB permissions prevent inserting into
    // `transit.routes` but schedules exist and should be shown to the driver.
    if (!DEV_MOCK && routes.length === 0) {
      const fallback = await db.query(
        `
          SELECT
            s.id,
            s.start_time,
            s.end_time,
            s.status,
            s.bus_line_id,
            bl.line_number,
            bl.start_stop,
            bl.end_stop,
            bl.estimated_duration_minutes,
            bl.description,
            s.bus_id,
            bt.id as bus_type_id,
            bt.name as bus_type,
            bt.seat_capacity,
            bt.license_plate
          FROM transit.schedules s
          JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          JOIN fleet.bus bt ON s.bus_id = bt.id
          WHERE s.driver_id = $1 AND DATE(s.start_time) = $2
          ORDER BY s.start_time ASC
        `,
        [userId, date],
      );

      routes = fallback.rows.map((row) => ({
        id: row.id,
        startTime: row.start_time,
        endTime: row.end_time,
        status: row.status,
        busLine: {
          id: row.bus_line_id,
          lineNumber: row.line_number,
          startStop: row.start_stop,
          endStop: row.end_stop,
          estimatedDuration: row.estimated_duration_minutes,
          description: row.description,
        },
        busType: {
          id: row.bus_type_id,
          name: row.bus_type,
          seatCapacity: row.seat_capacity,
          licensePlate: row.license_plate,
        },
      }));
    }

    // If still empty, try to synthesize a single route by shifting a recent
    // schedule's time-of-day to the requested date. This is a non-destructive
    // fallback to make sure drivers see a trip when DB inserts are restricted.
    if (!DEV_MOCK && routes.length === 0) {
      const tmplRes = await db.query(
        `
          SELECT s.start_time, s.end_time, s.status, s.bus_line_id, s.bus_id, s.driver_id, bl.estimated_duration_minutes, bl.line_number, bl.start_stop, bl.end_stop, bl.description
          FROM transit.schedules s
          JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          WHERE s.driver_id = $1
          ORDER BY s.start_time DESC
          LIMIT 1
        `,
        [userId],
      );

      if (tmplRes.rowCount > 0) {
        const t = tmplRes.rows[0];
        const requestedDate = new Date(date + "T00:00:00.000Z");
        const srcStart = new Date(t.start_time);
        const srcEnd = new Date(t.end_time);

        // Preserve time-of-day from template, apply to requested date
        const newStart = new Date(requestedDate);
        newStart.setUTCHours(
          srcStart.getUTCHours(),
          srcStart.getUTCMinutes(),
          srcStart.getUTCSeconds(),
          srcStart.getUTCMilliseconds(),
        );
        const durationMs = srcEnd.getTime() - srcStart.getTime();
        const newEnd = new Date(newStart.getTime() + durationMs);

        routes.push({
          id: null,
          startTime: newStart.toISOString(),
          endTime: newEnd.toISOString(),
          status: t.status || "planned",
          busLine: {
            id: t.bus_line_id,
            lineNumber: t.line_number,
            startStop: t.start_stop,
            endStop: t.end_stop,
            estimatedDuration: t.estimated_duration_minutes,
            description: t.description,
          },
          busType: {
            id: t.bus_id,
            name: null,
            seatCapacity: null,
            licensePlate: null,
          },
        });
      }
    }

    res.json({ date, routes });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// DRIVER - Weekly schedule templates assigned through transit.shifts.
// day_of_week uses JavaScript/PostgreSQL convention: 0 Sunday, 1 Monday ... 6 Saturday.
app.get("/driver/schedules/daily", authMiddleware, async (req, res) => {
  try {
    const { date } = req.query;
    if (!isValidDateKey(date)) {
      return res.status(400).json({ error: "date must use YYYY-MM-DD format" });
    }

    const result = await db.query(
      `
      SELECT s.id, s.bus_line_id, s.start_time, s.end_time, s.status, s.day_of_week,
             bl.line_number, bl.start_stop, bl.end_stop, bl.estimated_duration_minutes,
             bl.description
      FROM transit.schedules s
      JOIN transit.bus_lines bl ON bl.id = s.bus_line_id
      WHERE EXISTS (
          SELECT 1
          FROM transit.shifts sh
          WHERE sh.schedule_id = s.id AND sh.driver_id = $1
        )
        AND s.day_of_week = EXTRACT(DOW FROM $2::date)::int
        AND s.status <> 'cancelled'
      ORDER BY s.start_time ASC
    `,
      [req.user.userId, date],
    );

    res.json({
      date,
      routes: result.rows.map((row) => ({
        id: Number(row.id),
        startTime: row.start_time,
        endTime: row.end_time,
        status: row.status,
        dayOfWeek: Number(row.day_of_week),
        busLine: {
          id: Number(row.bus_line_id),
          lineNumber: row.line_number,
          startStop: row.start_stop,
          endStop: row.end_stop,
          estimatedDuration: row.estimated_duration_minutes,
          description: row.description,
        },
      })),
    });
  } catch (err) {
    console.error("GET /driver/schedules/daily error:", err);
    res.status(500).json({ error: "internal_error" });
  }
});

// ============================================
// ROUTES - Get single route details
// ============================================
app.get("/routes/:routeId", authMiddleware, async (req, res) => {
  try {
    const { routeId } = req.params;
    const userId = req.user.userId;

    const result = await db.query(
      `
      SELECT 
        r.id,
        r.start_time,
        r.end_time,
        r.status,
        bl.id as line_id,
        bl.line_number,
        bl.start_stop,
        bl.end_stop,
        bl.estimated_duration_minutes,
        bl.description,
        bt.id as bus_type_id,
        bt.name as bus_type,
        bt.seat_capacity,
        bt.license_plate
      FROM routes r
      JOIN bus_lines bl ON r.bus_line_id = bl.id
      JOIN bus_types bt ON r.bus_type_id = bt.id
      WHERE r.id = $1 AND r.user_id = $2
    `,
      [routeId, userId],
    );

    if (result.rows.length === 0) {
      return res.status(404).json({ error: "route_not_found" });
    }

    const row = result.rows[0];
    const route = {
      id: row.id,
      startTime: row.start_time,
      endTime: row.end_time,
      status: row.status,
      busLine: {
        id: row.line_id,
        lineNumber: row.line_number,
        startStop: row.start_stop,
        endStop: row.end_stop,
        estimatedDuration: row.estimated_duration_minutes,
        description: row.description,
      },
      busType: {
        id: row.bus_type_id,
        name: row.bus_type,
        seatCapacity: row.seat_capacity,
        licensePlate: row.license_plate,
      },
    };

    res.json({ route });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ROUTES - Get stops for a bus line
// ============================================
app.get("/bus-lines/:busLineId/stops", authMiddleware, async (req, res) => {
  try {
    const { busLineId } = req.params;
    if (DEV_MOCK) {
      const stops = _mock.routeStops
        .filter((rs) => String(rs.busLineId) === String(busLineId))
        .sort((a, b) => a.stopOrder - b.stopOrder)
        .map((rs) => ({
          id: rs.id,
          order: rs.stopOrder,
          name: rs.name,
          latitude: rs.latitude,
          longitude: rs.longitude,
          estimatedArrivalMinutes: rs.estimatedArrivalMinutes,
        }));
      return res.json({ stops });
    }

    const result = await db.query(
      `
      SELECT
        rs.id,
        rs.stop_order,
        s.name as stop_name,
        s.latitude,
        s.longitude,
        rs.estimated_arrival_minutes
      FROM transit.route_stops rs
      JOIN transit.stops s ON s.id = rs.stop_id
      WHERE rs.bus_line_id = $1
      ORDER BY rs.stop_order ASC
    `,
      [busLineId],
    );

    const stops = result.rows.map((row) => ({
      id: row.id,
      order: row.stop_order,
      name: row.stop_name,
      latitude: parseFloat(row.latitude),
      longitude: parseFloat(row.longitude),
      estimatedArrivalMinutes: row.estimated_arrival_minutes,
    }));

    res.json({ stops });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ADMIN - Create reusable stop
// ============================================
app.get("/admin/stops", authMiddleware, adminMiddleware, async (req, res) => {
  try {
    if (DEV_MOCK) {
      return res.json({
        stops: _mock.stops.slice().sort((a, b) => a.id - b.id),
      });
    }

    const result = await db.query(`
      SELECT id, name, latitude, longitude, created_at, updated_at
      FROM transit.stops
      ORDER BY id ASC
    `);

    res.json({
      stops: result.rows.map((row) => ({
        id: row.id,
        name: row.name,
        latitude: parseFloat(row.latitude),
        longitude: parseFloat(row.longitude),
        createdAt: row.created_at,
        updatedAt: row.updated_at,
      })),
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

app.post("/admin/stops", authMiddleware, adminMiddleware, async (req, res) => {
  try {
    const { name, latitude, longitude } = req.body;

    if (!name || latitude === undefined || longitude === undefined) {
      return res.status(400).json({ error: "missing_required_fields" });
    }

    if (DEV_MOCK) {
      const stop = {
        id: _mock.nextStopId++,
        name,
        latitude: parseFloat(latitude),
        longitude: parseFloat(longitude),
        createdAt: new Date().toISOString(),
        updatedAt: new Date().toISOString(),
      };
      _mock.stops.push(stop);
      return res.status(201).json({ stop });
    }

    const result = await db.query(
      `
      WITH next_id AS (
        SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.stops
      )
      INSERT INTO transit.stops (id, name, latitude, longitude)
      SELECT next_id.id, $1, $2, $3
      FROM next_id
      RETURNING id, name, latitude, longitude, created_at, updated_at
    `,
      [name, latitude, longitude],
    );

    const stop = result.rows[0];
    res.status(201).json({
      stop: {
        id: stop.id,
        name: stop.name,
        latitude: parseFloat(stop.latitude),
        longitude: parseFloat(stop.longitude),
        createdAt: stop.created_at,
        updatedAt: stop.updated_at,
      },
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ADMIN - Manage bus lines
// ============================================
app.get(
  "/admin/bus-lines",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      if (DEV_MOCK) {
        return res.json({
          busLines: _mock.busLines
            .slice()
            .sort((a, b) => a.lineNumber - b.lineNumber),
        });
      }

      const result = await db.query(`
      SELECT id, line_number, start_stop, end_stop, estimated_duration_minutes, description
      FROM transit.bus_lines
      ORDER BY line_number ASC, id ASC
    `);

      res.json({
        busLines: result.rows.map((row) => ({
          id: row.id,
          lineNumber: row.line_number,
          startStop: row.start_stop,
          endStop: row.end_stop,
          estimatedDurationMinutes: row.estimated_duration_minutes,
          description: row.description,
        })),
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/bus-lines",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const {
        lineNumber,
        startStop,
        endStop,
        estimatedDurationMinutes,
        description,
      } = req.body;

      if (
        lineNumber === undefined ||
        !startStop ||
        !endStop ||
        estimatedDurationMinutes === undefined
      ) {
        return res.status(400).json({ error: "missing_required_fields" });
      }

      if (DEV_MOCK) {
        const busLine = {
          id: _mock.nextBusLineId++,
          lineNumber: Number(lineNumber),
          startStop,
          endStop,
          estimatedDurationMinutes: Number(estimatedDurationMinutes),
          description: description || "",
          createdAt: new Date().toISOString(),
          updatedAt: new Date().toISOString(),
        };
        _mock.busLines.push(busLine);
        return res.status(201).json({ busLine });
      }

      const result = await db.query(
        `
      WITH next_id AS (
        SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.bus_lines
      )
      INSERT INTO transit.bus_lines (id, line_number, start_stop, end_stop, estimated_duration_minutes, description)
      SELECT next_id.id, $1, $2, $3, $4, $5
      FROM next_id
      RETURNING id, line_number, start_stop, end_stop, estimated_duration_minutes, description
    `,
        [
          lineNumber,
          startStop,
          endStop,
          estimatedDurationMinutes,
          description || null,
        ],
      );

      const busLine = result.rows[0];
      res.status(201).json({
        busLine: {
          id: busLine.id,
          lineNumber: busLine.line_number,
          startStop: busLine.start_stop,
          endStop: busLine.end_stop,
          estimatedDurationMinutes: busLine.estimated_duration_minutes,
          description: busLine.description,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.patch(
  "/admin/bus-lines/:busLineId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busLineId } = req.params;
      const {
        lineNumber,
        startStop,
        endStop,
        estimatedDurationMinutes,
        description,
      } = req.body;

      if (DEV_MOCK) {
        const existing = _mock.busLines.find(
          (line) => String(line.id) === String(busLineId),
        );
        if (!existing)
          return res.status(404).json({ error: "bus_line_not_found" });
        if (lineNumber !== undefined) existing.lineNumber = Number(lineNumber);
        if (startStop !== undefined) existing.startStop = startStop;
        if (endStop !== undefined) existing.endStop = endStop;
        if (estimatedDurationMinutes !== undefined)
          existing.estimatedDurationMinutes = Number(estimatedDurationMinutes);
        if (description !== undefined) existing.description = description;
        existing.updatedAt = new Date().toISOString();
        return res.json({ busLine: existing });
      }

      const result = await db.query(
        `
      UPDATE transit.bus_lines
      SET
        line_number = COALESCE($1, line_number),
        start_stop = COALESCE($2, start_stop),
        end_stop = COALESCE($3, end_stop),
        estimated_duration_minutes = COALESCE($4, estimated_duration_minutes),
        description = COALESCE($5, description)
      WHERE id = $6
      RETURNING id, line_number, start_stop, end_stop, estimated_duration_minutes, description
    `,
        [
          lineNumber ?? null,
          startStop ?? null,
          endStop ?? null,
          estimatedDurationMinutes ?? null,
          description ?? null,
          busLineId,
        ],
      );

      if (!result.rows[0])
        return res.status(404).json({ error: "bus_line_not_found" });

      const busLine = result.rows[0];
      res.json({
        busLine: {
          id: busLine.id,
          lineNumber: busLine.line_number,
          startStop: busLine.start_stop,
          endStop: busLine.end_stop,
          estimatedDurationMinutes: busLine.estimated_duration_minutes,
          description: busLine.description,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Manage fleet buses
// ============================================
app.get(
  "/admin/fleet/buses",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      if (DEV_MOCK) {
        const buses = _mock.fleetBuses.slice().sort((a, b) => a.id - b.id);
        return res.json({
          buses: buses.map((b) => ({
            ...b,
            available: !checkBusConflict(
              b.id,
              new Date().toISOString(),
              new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
              [],
              _mock.schedules || [],
            ),
          })),
        });
      }

      const result = await db.query(`
      SELECT id, name, seat_capacity, license_plate
      FROM fleet.bus
      ORDER BY id ASC
    `);

      // Get all schedules to check for conflicts
      const schedulesResult = await db.query(
        `SELECT * FROM transit.schedules WHERE status IN ('planned', 'active')`,
      );
      const schedules = schedulesResult.rows.map((row) => ({
        ...row,
        weekdays: parseWeekdaysValue(row.weekdays),
      }));

      res.json({
        buses: result.rows.map((row) => {
          const busId = row.id;
          const now = new Date();
          const tomorrow = new Date(now);
          tomorrow.setDate(tomorrow.getDate() + 1);
          const isAvailable = !checkBusConflict(
            busId,
            now.toISOString(),
            tomorrow.toISOString(),
            [],
            schedules,
          );

          return {
            id: row.id,
            name: row.name,
            seatCapacity: row.seat_capacity,
            licensePlate: row.license_plate,
            available: isAvailable,
          };
        }),
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/fleet/buses",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { name, seatCapacity, licensePlate } = req.body;

      if (!name || seatCapacity === undefined || !licensePlate) {
        return res.status(400).json({ error: "missing_required_fields" });
      }

      if (DEV_MOCK) {
        const bus = {
          id: _mock.nextFleetBusId++,
          name,
          seatCapacity: Number(seatCapacity),
          licensePlate,
          createdAt: new Date().toISOString(),
          updatedAt: new Date().toISOString(),
        };
        _mock.fleetBuses.push(bus);
        return res.status(201).json({ bus });
      }

      const result = await db.query(
        `
      WITH next_id AS (
        SELECT COALESCE(MAX(id), 0) + 1 AS id FROM fleet.bus
      )
      INSERT INTO fleet.bus (id, name, seat_capacity, license_plate)
      SELECT next_id.id, $1, $2, $3
      FROM next_id
      RETURNING id, name, seat_capacity, license_plate
    `,
        [name, seatCapacity, licensePlate],
      );

      const bus = result.rows[0];
      res.status(201).json({
        bus: {
          id: bus.id,
          name: bus.name,
          seatCapacity: bus.seat_capacity,
          licensePlate: bus.license_plate,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Update fleet bus
// ============================================
app.patch(
  "/admin/fleet/buses/:busId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busId } = req.params;
      const { name, seatCapacity, licensePlate } = req.body;

      if (!busId || !Number.isFinite(Number(busId))) {
        return res.status(400).json({ error: "invalid_bus_id" });
      }

      if (DEV_MOCK) {
        const bus = _mock.fleetBuses.find(
          (b) => Number(b.id) === Number(busId),
        );
        if (!bus) return res.status(404).json({ error: "bus_not_found" });
        if (name !== undefined) bus.name = name;
        if (seatCapacity !== undefined) bus.seatCapacity = Number(seatCapacity);
        if (licensePlate !== undefined) bus.licensePlate = licensePlate;
        bus.updatedAt = new Date().toISOString();
        return res.json({ bus });
      }

      const result = await db.query(
        `
      UPDATE fleet.bus
      SET name = COALESCE($1, name), seat_capacity = COALESCE($2, seat_capacity), license_plate = COALESCE($3, license_plate), updated_at = NOW()
      WHERE id = $4
      RETURNING id, name, seat_capacity, license_plate
    `,
        [name ?? null, seatCapacity ?? null, licensePlate ?? null, busId],
      );

      if (!result.rows[0])
        return res.status(404).json({ error: "bus_not_found" });

      const bus = result.rows[0];
      res.json({
        bus: {
          id: bus.id,
          name: bus.name,
          seatCapacity: bus.seat_capacity,
          licensePlate: bus.license_plate,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Delete fleet bus
// ============================================
app.delete(
  "/admin/fleet/buses/:busId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busId } = req.params;
      if (!busId || !Number.isFinite(Number(busId))) {
        return res.status(400).json({ error: "invalid_bus_id" });
      }

      if (DEV_MOCK) {
        const idx = _mock.fleetBuses.findIndex(
          (b) => Number(b.id) === Number(busId),
        );
        if (idx === -1) return res.status(404).json({ error: "bus_not_found" });
        const deleted = _mock.fleetBuses.splice(idx, 1)[0];
        return res.json({ success: true, bus: deleted });
      }

      const result = await db.query(
        `DELETE FROM fleet.bus WHERE id = $1 RETURNING id, name`,
        [busId],
      );
      if (result.rows.length === 0)
        return res.status(404).json({ error: "bus_not_found" });
      res.json({ success: true, bus: result.rows[0] });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Link stop to bus line
// ============================================
app.get(
  "/admin/bus-lines/:busLineId/stops",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busLineId } = req.params;
      if (!busLineId || !Number.isFinite(Number(busLineId))) {
        return res.status(400).json({ error: "invalid_bus_line_id" });
      }

      if (DEV_MOCK) {
        const stops = _mock.routeStops
          .filter((rs) => String(rs.busLineId) === String(busLineId))
          .sort((a, b) => a.stopOrder - b.stopOrder)
          .map((rs) => ({
            id: rs.id,
            busLineId: rs.busLineId,
            stopId: rs.stopId,
            stopOrder: rs.stopOrder,
            estimatedArrivalMinutes: rs.estimatedArrivalMinutes,
            name: rs.name,
            latitude: rs.latitude,
            longitude: rs.longitude,
          }));
        return res.json({ routeStops: stops });
      }

      const result = await db.query(
        `
      SELECT
        rs.id,
        rs.bus_line_id,
        rs.stop_id,
        rs.stop_order,
        rs.estimated_arrival_minutes,
        s.name as stop_name,
        s.latitude,
        s.longitude
      FROM transit.route_stops rs
      JOIN transit.stops s ON s.id = rs.stop_id
      WHERE rs.bus_line_id = $1
      ORDER BY rs.stop_order ASC
    `,
        [busLineId],
      );

      res.json({
        routeStops: result.rows.map((row) => ({
          id: row.id,
          busLineId: row.bus_line_id,
          stopId: row.stop_id,
          stopOrder: row.stop_order,
          estimatedArrivalMinutes: row.estimated_arrival_minutes,
          name: row.stop_name,
          latitude: parseFloat(row.latitude),
          longitude: parseFloat(row.longitude),
        })),
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/bus-lines/:busLineId/stops",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busLineId } = req.params;
      const { stopId, stopOrder, estimatedArrivalMinutes } = req.body;

      if (!stopId || stopOrder === undefined) {
        return res.status(400).json({ error: "missing_required_fields" });
      }

      if (DEV_MOCK) {
        const stop = _mock.stops.find((s) => String(s.id) === String(stopId));
        const routeStop = {
          id: _mock.nextRouteStopId++,
          busLineId: Number(busLineId),
          stopId: Number(stopId),
          stopOrder: Number(stopOrder),
          estimatedArrivalMinutes: estimatedArrivalMinutes ?? null,
          createdAt: new Date().toISOString(),
          updatedAt: new Date().toISOString(),
          name: stop ? stop.name : `stop-${stopId}`,
          latitude: stop ? stop.latitude : 0,
          longitude: stop ? stop.longitude : 0,
        };
        // remove existing with same busLineId & stopOrder
        _mock.routeStops = _mock.routeStops.filter(
          (rs) =>
            !(
              rs.busLineId === routeStop.busLineId &&
              rs.stopOrder === routeStop.stopOrder
            ),
        );
        _mock.routeStops.push(routeStop);
        return res.status(201).json({ routeStop });
      }

      const result = await db.query(
        `
      WITH next_id AS (
        SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.route_stops
      )
      INSERT INTO transit.route_stops (id, bus_line_id, stop_id, stop_order, estimated_arrival_minutes)
      SELECT next_id.id, $1, $2, $3, $4
      FROM next_id
      ON CONFLICT (bus_line_id, stop_order) DO UPDATE SET
        stop_id = EXCLUDED.stop_id,
        estimated_arrival_minutes = EXCLUDED.estimated_arrival_minutes,
        updated_at = NOW()
      RETURNING id, bus_line_id, stop_id, stop_order, estimated_arrival_minutes, created_at, updated_at
    `,
        [busLineId, stopId, stopOrder, estimatedArrivalMinutes ?? null],
      );

      const link = result.rows[0];
      res.status(201).json({
        routeStop: {
          id: link.id,
          busLineId: link.bus_line_id,
          stopId: link.stop_id,
          stopOrder: link.stop_order,
          estimatedArrivalMinutes: link.estimated_arrival_minutes,
          createdAt: link.created_at,
          updatedAt: link.updated_at,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/bus-lines/:busLineId/stops/reorder",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    const client = await db.pool.connect();
    try {
      const { busLineId } = req.params;
      const { routeStopIds } = req.body || {};

      if (!Array.isArray(routeStopIds) || routeStopIds.length === 0) {
        return res.status(400).json({ error: "routeStopIds array required" });
      }

      const normalizedIds = routeStopIds
        .map((id) => Number(id))
        .filter((id) => Number.isFinite(id));
      if (normalizedIds.length !== routeStopIds.length) {
        return res
          .status(400)
          .json({ error: "routeStopIds must contain only numeric ids" });
      }

      if (DEV_MOCK) {
        const busLineStops = _mock.routeStops
          .filter((rs) => String(rs.busLineId) === String(busLineId))
          .sort((a, b) => a.stopOrder - b.stopOrder);

        const idSet = new Set(busLineStops.map((rs) => Number(rs.id)));
        const sameCount = busLineStops.length === normalizedIds.length;
        const sameIds = sameCount && normalizedIds.every((id) => idSet.has(id));
        if (!sameIds) {
          return res
            .status(400)
            .json({ error: "routeStopIds must match current bus line stops" });
        }

        const updated = normalizedIds.map((routeStopId, index) => {
          const stop = _mock.routeStops.find(
            (rs) =>
              Number(rs.id) === routeStopId &&
              String(rs.busLineId) === String(busLineId),
          );
          if (!stop) return null;
          stop.stopOrder = index + 1;
          stop.updatedAt = new Date().toISOString();
          return stop;
        });

        if (updated.some((item) => !item)) {
          return res
            .status(400)
            .json({ error: "routeStopIds must match current bus line stops" });
        }

        _mock.routeStops = _mock.routeStops.map((routeStop) => {
          const reordered = updated.find((item) => item.id === routeStop.id);
          return reordered || routeStop;
        });

        return res.json({
          routeStops: updated,
        });
      }

      const current = await client.query(
        `SELECT id FROM transit.route_stops WHERE bus_line_id = $1 ORDER BY stop_order ASC`,
        [busLineId],
      );

      const currentIds = current.rows.map((row) => Number(row.id));
      const sameCount = currentIds.length === normalizedIds.length;
      const sameIds =
        sameCount && normalizedIds.every((id) => currentIds.includes(id));

      if (!sameIds) {
        return res
          .status(400)
          .json({ error: "routeStopIds must match current bus line stops" });
      }

      await client.query("BEGIN");

      for (let index = 0; index < normalizedIds.length; index += 1) {
        await client.query(
          `UPDATE transit.route_stops
         SET stop_order = $1, updated_at = NOW()
         WHERE id = $2 AND bus_line_id = $3`,
          [-(index + 1), normalizedIds[index], busLineId],
        );
      }

      for (let index = 0; index < normalizedIds.length; index += 1) {
        await client.query(
          `UPDATE transit.route_stops
         SET stop_order = $1, updated_at = NOW()
         WHERE id = $2 AND bus_line_id = $3`,
          [index + 1, normalizedIds[index], busLineId],
        );
      }

      const result = await client.query(
        `SELECT
         rs.id,
         rs.stop_order,
         s.name as stop_name,
         s.latitude,
         s.longitude,
         rs.estimated_arrival_minutes
       FROM transit.route_stops rs
       JOIN transit.stops s ON s.id = rs.stop_id
       WHERE rs.bus_line_id = $1
       ORDER BY rs.stop_order ASC`,
        [busLineId],
      );

      await client.query("COMMIT");

      res.json({
        routeStops: result.rows.map((row) => ({
          id: row.id,
          order: row.stop_order,
          name: row.stop_name,
          latitude: parseFloat(row.latitude),
          longitude: parseFloat(row.longitude),
          estimatedArrivalMinutes: row.estimated_arrival_minutes,
        })),
      });
    } catch (err) {
      await client.query("ROLLBACK").catch(() => {});
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    } finally {
      client.release();
    }
  },
);

// ============================================
// ADMIN - Delete a stop
// ============================================
app.delete(
  "/admin/stops/:stopId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { stopId } = req.params;

      if (!stopId || !Number.isFinite(Number(stopId))) {
        return res.status(400).json({ error: "invalid_stop_id" });
      }

      if (DEV_MOCK) {
        const index = _mock.stops.findIndex(
          (s) => Number(s.id) === Number(stopId),
        );
        if (index === -1) {
          return res.status(404).json({ error: "stop_not_found" });
        }
        const deletedStop = _mock.stops.splice(index, 1)[0];
        return res.json({ success: true, stop: deletedStop });
      }

      const result = await db.query(
        `DELETE FROM transit.stops WHERE id = $1 RETURNING id, name`,
        [stopId],
      );

      if (result.rows.length === 0) {
        return res.status(404).json({ error: "stop_not_found" });
      }

      res.json({ success: true, stop: result.rows[0] });
    } catch (err) {
      console.error(err);
      if (err.code === "23503") {
        return res.status(409).json({
          error: "foreign_key_violation",
          message: "This stop is referenced by route_stops",
        });
      }
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Update a stop
// ============================================
app.patch(
  "/admin/stops/:stopId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { stopId } = req.params;
      const { name, latitude, longitude } = req.body;

      if (!stopId || !Number.isFinite(Number(stopId))) {
        return res.status(400).json({ error: "invalid_stop_id" });
      }

      if (DEV_MOCK) {
        const stop = _mock.stops.find((s) => Number(s.id) === Number(stopId));
        if (!stop) return res.status(404).json({ error: "stop_not_found" });
        if (name !== undefined) stop.name = name;
        if (latitude !== undefined) stop.latitude = parseFloat(latitude);
        if (longitude !== undefined) stop.longitude = parseFloat(longitude);
        stop.updatedAt = new Date().toISOString();
        return res.json({ stop });
      }

      const result = await db.query(
        `UPDATE transit.stops
       SET name = COALESCE($1, name),
           latitude = COALESCE($2, latitude),
           longitude = COALESCE($3, longitude),
           updated_at = NOW()
       WHERE id = $4
       RETURNING id, name, latitude, longitude, created_at, updated_at`,
        [name ?? null, latitude ?? null, longitude ?? null, stopId],
      );

      if (!result.rows[0])
        return res.status(404).json({ error: "stop_not_found" });

      const stop = result.rows[0];
      res.json({
        stop: {
          id: stop.id,
          name: stop.name,
          latitude: parseFloat(stop.latitude),
          longitude: parseFloat(stop.longitude),
          createdAt: stop.created_at,
          updatedAt: stop.updated_at,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Delete a bus line
// ============================================
app.delete(
  "/admin/bus-lines/:busLineId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    const client = await db.pool.connect();
    try {
      const { busLineId } = req.params;

      if (!busLineId || !Number.isFinite(Number(busLineId))) {
        return res.status(400).json({ error: "invalid_bus_line_id" });
      }

      if (DEV_MOCK) {
        const lineIndex = _mock.busLines.findIndex(
          (bl) => Number(bl.id) === Number(busLineId),
        );
        if (lineIndex === -1) {
          return res.status(404).json({ error: "bus_line_not_found" });
        }
        const deletedLine = _mock.busLines.splice(lineIndex, 1)[0];
        // Also delete route_stops for this line
        _mock.routeStops = _mock.routeStops.filter(
          (rs) => String(rs.busLineId) !== String(busLineId),
        );
        return res.json({ success: true, busLine: deletedLine });
      }

      await client.query("BEGIN");

      // Delete associated route_stops first
      await client.query(
        `DELETE FROM transit.route_stops WHERE bus_line_id = $1`,
        [busLineId],
      );

      // Delete the bus line
      const result = await client.query(
        `DELETE FROM transit.bus_lines WHERE id = $1 RETURNING id, line_number`,
        [busLineId],
      );

      if (result.rows.length === 0) {
        await client.query("ROLLBACK");
        return res.status(404).json({ error: "bus_line_not_found" });
      }

      await client.query("COMMIT");
      res.json({ success: true, busLine: result.rows[0] });
    } catch (err) {
      await client.query("ROLLBACK").catch(() => {});
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    } finally {
      client.release();
    }
  },
);

// ============================================
// ADMIN - Delete a route_stop from bus line
// ============================================
app.delete(
  "/admin/bus-lines/:busLineId/stops/:routeStopId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    const client = await db.pool.connect();
    try {
      const { busLineId, routeStopId } = req.params;

      if (!busLineId || !Number.isFinite(Number(busLineId))) {
        return res.status(400).json({ error: "invalid_bus_line_id" });
      }

      if (!routeStopId || !Number.isFinite(Number(routeStopId))) {
        return res.status(400).json({ error: "invalid_route_stop_id" });
      }

      if (DEV_MOCK) {
        const index = _mock.routeStops.findIndex(
          (rs) =>
            Number(rs.id) === Number(routeStopId) &&
            String(rs.busLineId) === String(busLineId),
        );
        if (index === -1) {
          return res.status(404).json({ error: "route_stop_not_found" });
        }
        const deletedRouteStop = _mock.routeStops.splice(index, 1)[0];
        return res.json({ success: true, routeStop: deletedRouteStop });
      }

      await client.query("BEGIN");

      // Find and delete the route_stop
      const result = await client.query(
        `DELETE FROM transit.route_stops
       WHERE id = $1 AND bus_line_id = $2
       RETURNING id, stop_order`,
        [routeStopId, busLineId],
      );

      if (result.rows.length === 0) {
        await client.query("ROLLBACK");
        return res.status(404).json({ error: "route_stop_not_found" });
      }

      const deletedOrder = result.rows[0].stop_order;

      // Re-order remaining stops
      await client.query(
        `UPDATE transit.route_stops
       SET stop_order = stop_order - 1, updated_at = NOW()
       WHERE bus_line_id = $1 AND stop_order > $2`,
        [busLineId, deletedOrder],
      );

      await client.query("COMMIT");
      res.json({ success: true, routeStop: result.rows[0] });
    } catch (err) {
      await client.query("ROLLBACK").catch(() => {});
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    } finally {
      client.release();
    }
  },
);

// ============================================
// NAVIGATION - Save calculated route
// ============================================
app.post("/navigation/route", authMiddleware, async (req, res) => {
  try {
    const {
      routeId,
      startLat,
      startLon,
      endLat,
      endLon,
      totalDistance,
      totalDuration,
      geojson,
    } = req.body;

    if (
      !routeId ||
      !startLat ||
      !startLon ||
      !endLat ||
      !endLon ||
      !totalDistance ||
      !totalDuration
    ) {
      return res.status(400).json({ error: "missing_required_fields" });
    }

    const result = await db.query(
      `
      INSERT INTO navigation_routes 
      (route_id, start_lat, start_lon, end_lat, end_lon, 
       total_distance_meters, total_duration_seconds, polyline_geojson)
      VALUES ($1, $2, $3, $4, $5, $6, $7, $8)
      ON CONFLICT (route_id) DO UPDATE SET
        start_lat = $2,
        start_lon = $3,
        end_lat = $4,
        end_lon = $5,
        total_distance_meters = $6,
        total_duration_seconds = $7,
        polyline_geojson = $8
      RETURNING *
    `,
      [
        routeId,
        startLat,
        startLon,
        endLat,
        endLon,
        totalDistance,
        totalDuration,
        JSON.stringify(geojson),
      ],
    );

    res.json({ route: result.rows[0] });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// GPS TRACKING - Record current position
// ============================================
app.post("/gps/track", authMiddleware, async (req, res) => {
  try {
    const { routeId, latitude, longitude, speed, heading, accuracy } = req.body;

    if (!routeId || !latitude || !longitude) {
      return res.status(400).json({ error: "missing_required_fields" });
    }

    await db.query(
      `
      INSERT INTO gps_tracking 
      (route_id, latitude, longitude, speed_kmh, heading, accuracy, recorded_at)
      VALUES ($1, $2, $3, $4, $5, $6, NOW())
    `,
      [
        routeId,
        latitude,
        longitude,
        speed || null,
        heading || null,
        accuracy || null,
      ],
    );

    res.json({ ok: true });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// GPS TRACKING - Get route history
// ============================================
app.get("/gps/route/:routeId", authMiddleware, async (req, res) => {
  try {
    const { routeId } = req.params;
    const userId = req.user.userId;

    // Verify user owns this route
    const routeCheck = await db.query(
      "SELECT id FROM routes WHERE id = $1 AND user_id = $2",
      [routeId, userId],
    );

    if (routeCheck.rows.length === 0) {
      return res.status(403).json({ error: "unauthorized" });
    }

    const result = await db.query(
      `
      SELECT 
        id,
        latitude,
        longitude,
        speed_kmh,
        heading,
        accuracy,
        recorded_at
      FROM gps_tracking
      WHERE route_id = $1
      ORDER BY recorded_at ASC
    `,
      [routeId],
    );

    const positions = result.rows.map((row) => ({
      id: row.id,
      latitude: parseFloat(row.latitude),
      longitude: parseFloat(row.longitude),
      speed: row.speed_kmh,
      heading: row.heading,
      accuracy: row.accuracy,
      recordedAt: row.recorded_at,
    }));

    res.json({ positions });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ROUTES - Update route status
// ============================================
app.patch("/routes/:routeId/status", authMiddleware, async (req, res) => {
  try {
    const { routeId } = req.params;
    const { status } = req.body;
    const userId = req.user.userId;

    const validStatuses = [
      "scheduled",
      "in_progress",
      "completed",
      "cancelled",
    ];
    if (!validStatuses.includes(status)) {
      return res.status(400).json({ error: "invalid_status" });
    }

    const result = await db.query(
      `
      UPDATE transit.routes 
      SET status = $1, updated_at = NOW()
      WHERE id = $2 AND user_id = $3
      RETURNING *
    `,
      [status, routeId, userId],
    );

    if (result.rows.length === 0) {
      return res.status(404).json({ error: "route_not_found" });
    }

    res.json({ route: result.rows[0] });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// DRIVER - Update schedule status
// ============================================
app.patch(
  "/driver/weekly-schedules/:scheduleId/status",
  authMiddleware,
  async (req, res) => {
    try {
      const scheduleId = Number(req.params.scheduleId);
      const { status } = req.body;
      const validStatuses = [
        "planned",
        "in_progress",
        "completed",
        "cancelled",
        "active",
      ];
      if (!Number.isInteger(scheduleId) || !validStatuses.includes(status)) {
        return res.status(400).json({ error: "invalid_status" });
      }

      const normalizedStatus = status === "active" ? "in_progress" : status;
      const result = await db.query(
        `
      UPDATE transit.schedules s
      SET status = $1, updated_at = NOW()
      WHERE s.id = $2
        AND EXISTS (
          SELECT 1 FROM transit.shifts sh
          WHERE sh.schedule_id = s.id AND sh.driver_id = $3
        )
      RETURNING s.id, s.status
    `,
        [normalizedStatus, scheduleId, req.user.userId],
      );

      if (result.rows.length === 0)
        return res.status(404).json({ error: "schedule_not_found" });
      res.json({
        schedule: {
          id: Number(result.rows[0].id),
          status: result.rows[0].status,
        },
      });
    } catch (err) {
      console.error("PATCH /driver/weekly-schedules/:id/status error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.patch(
  "/driver/schedules/:scheduleId/status",
  authMiddleware,
  async (req, res) => {
    try {
      const { scheduleId } = req.params;
      const { status } = req.body;

      const validStatuses = [
        "planned",
        "in_progress",
        "completed",
        "cancelled",
        "active",
      ];
      if (!validStatuses.includes(status)) {
        return res.status(400).json({ error: "invalid_status" });
      }

      const normalizedStatus = status === "active" ? "in_progress" : status;

      // Fetch the target schedule row to detect recurring templates
      const existing = await db.query(
        `SELECT * FROM transit.schedules WHERE id = $1`,
        [scheduleId],
      );
      if (existing.rows.length === 0) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      const scheduleRow = existing.rows[0];
      const weekdays = parseWeekdaysValue(scheduleRow.weekdays);

      // Allow updating a specific occurrence of a recurring template by passing { date: 'YYYY-MM-DD' }
      const requestedDate = req.body.date || null; // optional date key

      if (weekdays && weekdays.length > 0) {
        // This is a recurring template. If a date was provided, or the template occurs today, operate on an instance.
        let targetDateKey = requestedDate;
        if (!targetDateKey) {
          const todayKey = new Date().toISOString().slice(0, 10);
          if (scheduleOccursOnDate(scheduleRow, todayKey)) {
            targetDateKey = todayKey;
          }
        }

        if (targetDateKey) {
          // Build occurrence start/end based on template times
          const templateStart = new Date(
            scheduleRow.start_time ?? scheduleRow.startTime,
          );
          const templateEnd = new Date(
            scheduleRow.end_time ?? scheduleRow.endTime,
          );
          const occurrenceStart = new Date(`${targetDateKey}T00:00:00`);
          occurrenceStart.setHours(
            templateStart.getHours(),
            templateStart.getMinutes(),
            templateStart.getSeconds(),
            templateStart.getMilliseconds(),
          );

          let occurrenceEnd = null;
          if (
            Number.isFinite(templateEnd.getTime()) &&
            Number.isFinite(templateStart.getTime())
          ) {
            const duration = templateEnd.getTime() - templateStart.getTime();
            occurrenceEnd = new Date(occurrenceStart.getTime() + duration);
          }

          // Check if a concrete instance already exists for this template/date
          const existingInstance = await db.query(
            `SELECT * FROM transit.schedules WHERE template_id = $1 AND DATE(start_time) = $2`,
            [scheduleId, targetDateKey],
          );

          if (existingInstance.rows.length > 0) {
            const upd = await db.query(
              `
            UPDATE transit.schedules SET status = $1, updated_at = NOW()
            WHERE id = $2
            RETURNING *
          `,
              [normalizedStatus, existingInstance.rows[0].id],
            );
            return res.json({ schedule: upd.rows[0] });
          }

          // Insert a new instance derived from template
          const hasTemplateIdCol = await db.query(`
          SELECT 1 FROM information_schema.columns
          WHERE table_schema='transit' AND table_name='schedules' AND column_name='template_id'
        `);

          let insertResult;
          if (hasTemplateIdCol.rows.length > 0) {
            insertResult = await db.query(
              `
            WITH next_id AS (SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules)
            INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status, template_id)
            SELECT next_id.id, $1, $2, $3, $4, $5, $6, $7
            FROM next_id
            RETURNING *
          `,
              [
                scheduleRow.bus_line_id,
                scheduleRow.bus_id,
                scheduleRow.driver_id,
                occurrenceStart.toISOString(),
                occurrenceEnd ? occurrenceEnd.toISOString() : null,
                normalizedStatus,
                scheduleId,
              ],
            );
          } else {
            insertResult = await db.query(
              `
            WITH next_id AS (SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules)
            INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status)
            SELECT next_id.id, $1, $2, $3, $4, $5, $6
            FROM next_id
            RETURNING *
          `,
              [
                scheduleRow.bus_line_id,
                scheduleRow.bus_id,
                scheduleRow.driver_id,
                occurrenceStart.toISOString(),
                occurrenceEnd ? occurrenceEnd.toISOString() : null,
                normalizedStatus,
              ],
            );
          }

          return res.json({ schedule: insertResult.rows[0] });
        }
      }

      // Fallback: update the schedule row directly (one-time or when no occurrence date is inferred)
      const result = await db.query(
        `
      UPDATE transit.schedules
      SET status = $1, updated_at = NOW()
      WHERE id = $2
      RETURNING *
    `,
        [normalizedStatus, scheduleId],
      );

      if (result.rows.length === 0) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      res.json({ schedule: result.rows[0] });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Get drivers for scheduling
// ============================================
app.get("/admin/drivers", authMiddleware, adminMiddleware, async (req, res) => {
  try {
    if (DEV_MOCK) {
      const drivers = _mock.drivers
        .slice()
        .filter((d) => d.status === "active");
      return res.json({
        drivers: drivers.map((d) => ({
          ...d,
          available: !checkDriverConflict(
            d.id,
            new Date().toISOString(),
            new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
            [],
            _mock.schedules || [],
          ),
        })),
      });
    }

    const result = await db.query(`
      SELECT id, firstname, lastname, email, phone, job, joined, status
      FROM workers.employees
      WHERE status = 'active'
      ORDER BY firstname, lastname ASC
    `);

    // Get all schedules to check for conflicts
    const schedulesResult = await db.query(
      `SELECT * FROM transit.schedules WHERE status IN ('planned', 'active')`,
    );
    const schedules = schedulesResult.rows.map((row) => ({
      ...row,
      weekdays: parseWeekdaysValue(row.weekdays),
    }));

    res.json({
      drivers: result.rows.map((row) => {
        const driverId = row.id;
        const now = new Date();
        const tomorrow = new Date(now);
        tomorrow.setDate(tomorrow.getDate() + 1);
        const isAvailable = !checkDriverConflict(
          driverId,
          now.toISOString(),
          tomorrow.toISOString(),
          [],
          schedules,
        );

        return {
          id: row.id,
          name: (
            String(row.firstname || "") +
            " " +
            String(row.lastname || "")
          ).trim(),
          email: row.email,
          phone: row.phone,
          job: row.job,
          joined: row.joined,
          status: row.status,
          available: isAvailable,
        };
      }),
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ADMIN - Manage schedules (timetable)
// ============================================
app.get(
  "/admin/shift-drivers",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const result = await db.query(`
      SELECT id, usercode
      FROM workers.users
      ORDER BY usercode ASC
    `);
      res.json({
        drivers: result.rows.map((row) => ({
          id: Number(row.id),
          name: String(row.usercode),
        })),
      });
    } catch (err) {
      console.error("GET /admin/shift-drivers error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.get(
  "/admin/weekly-schedules",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const result = await db.query(`
      SELECT s.id, s.bus_line_id, s.start_time, s.end_time, s.status, s.day_of_week,
             bl.line_number, bl.start_stop, bl.end_stop,
             sh.id AS shift_id, sh.driver_id, u.usercode AS driver_name
      FROM transit.schedules s
      JOIN transit.bus_lines bl ON bl.id = s.bus_line_id
      LEFT JOIN transit.shifts sh ON sh.schedule_id = s.id
      LEFT JOIN workers.users u ON u.id = sh.driver_id
      ORDER BY s.day_of_week ASC, s.start_time ASC, s.id ASC
    `);
      res.json({
        schedules: result.rows.map((row) => ({
          id: Number(row.id),
          busLineId: Number(row.bus_line_id),
          lineNumber: row.line_number,
          startStop: row.start_stop,
          endStop: row.end_stop,
          startTime: row.start_time,
          endTime: row.end_time,
          status: row.status,
          dayOfWeek: Number(row.day_of_week),
          shiftId: row.shift_id ? Number(row.shift_id) : null,
          driverId: row.driver_id ? Number(row.driver_id) : null,
          driverName: row.driver_name || null,
        })),
      });
    } catch (err) {
      console.error("GET /admin/weekly-schedules error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.post(
  "/admin/weekly-schedules",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const busLineId = Number(req.body?.busLineId);
      const dayOfWeek = Number(req.body?.dayOfWeek);
      const startTime = String(req.body?.startTime || "");
      const endTime = String(req.body?.endTime || "");
      const driverId = req.body?.driverId ? Number(req.body.driverId) : null;

      if (
        !Number.isInteger(busLineId) ||
        !Number.isInteger(dayOfWeek) ||
        dayOfWeek < 0 ||
        dayOfWeek > 6 ||
        !startTime ||
        !endTime
      ) {
        return res.status(400).json({
          error: "busLineId, dayOfWeek, startTime and endTime are required",
        });
      }

      const created = await db.query(
        `
      INSERT INTO transit.schedules (bus_line_id, start_time, end_time, status, day_of_week)
      VALUES ($1, $2::time, $3::time, 'planned', $4)
      RETURNING id, bus_line_id, start_time, end_time, status, day_of_week
    `,
        [busLineId, startTime, endTime, dayOfWeek],
      );

      const schedule = created.rows[0];
      if (driverId) {
        await db.query(
          `
        INSERT INTO transit.shifts (schedule_id, driver_id)
        VALUES ($1, $2)
      `,
          [schedule.id, driverId],
        );
      }

      res.status(201).json({
        schedule: {
          id: Number(schedule.id),
          busLineId: Number(schedule.bus_line_id),
          startTime: schedule.start_time,
          endTime: schedule.end_time,
          status: schedule.status,
          dayOfWeek: Number(schedule.day_of_week),
          driverId,
        },
      });
    } catch (err) {
      console.error("POST /admin/weekly-schedules error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.post(
  "/admin/weekly-schedules/bulk",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    const busLineId = Number(req.body?.busLineId);
    const dayOfWeeks = Array.isArray(req.body?.dayOfWeeks)
      ? req.body.dayOfWeeks
          .map(Number)
          .filter((day) => Number.isInteger(day) && day >= 0 && day <= 6)
      : [];
    const startTimes = Array.isArray(req.body?.startTimes)
      ? [...new Set(req.body.startTimes.map(String).filter(Boolean))]
      : [];
    const driverId = req.body?.driverId ? Number(req.body.driverId) : null;

    if (
      !Number.isInteger(busLineId) ||
      dayOfWeeks.length === 0 ||
      startTimes.length === 0
    ) {
      return res
        .status(400)
        .json({ error: "busLineId, dayOfWeeks and startTimes are required" });
    }

    const client = await db.pool.connect();
    try {
      await client.query("BEGIN");
      const line = await client.query(
        "SELECT estimated_duration_minutes FROM transit.bus_lines WHERE id = $1",
        [busLineId],
      );
      if (line.rows.length === 0) {
        await client.query("ROLLBACK");
        return res.status(404).json({ error: "bus_line_not_found" });
      }

      const duration = Number(line.rows[0].estimated_duration_minutes) || 60;
      const created = [];
      for (const dayOfWeek of dayOfWeeks) {
        for (const startTime of startTimes) {
          const result = await client.query(
            `INSERT INTO transit.schedules
              (bus_line_id, start_time, end_time, status, day_of_week)
             VALUES ($1, $2::time, ($2::time + ($3::text || ' minutes')::interval)::time, 'planned', $4)
             RETURNING id, bus_line_id, start_time, end_time, status, day_of_week`,
            [busLineId, startTime, duration, dayOfWeek],
          );
          const schedule = result.rows[0];
          if (driverId) {
            await client.query(
              "INSERT INTO transit.shifts (schedule_id, driver_id) VALUES ($1, $2)",
              [schedule.id, driverId],
            );
          }
          created.push(schedule);
        }
      }

      await client.query("COMMIT");
      res.status(201).json({
        createdCount: created.length,
        schedules: created.map((schedule) => ({
          id: Number(schedule.id),
          busLineId: Number(schedule.bus_line_id),
          startTime: schedule.start_time,
          endTime: schedule.end_time,
          status: schedule.status,
          dayOfWeek: Number(schedule.day_of_week),
          driverId,
        })),
      });
    } catch (err) {
      await client.query("ROLLBACK");
      console.error("POST /admin/weekly-schedules/bulk error:", err);
      res.status(500).json({ error: "internal_error" });
    } finally {
      client.release();
    }
  },
);

app.put(
  "/admin/weekly-schedules/:scheduleId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const scheduleId = Number(req.params.scheduleId);
      const busLineId = Number(req.body?.busLineId);
      const dayOfWeek = Number(req.body?.dayOfWeek);
      const startTime = String(req.body?.startTime || "");
      const endTime = String(req.body?.endTime || "");
      if (
        !Number.isInteger(scheduleId) ||
        !Number.isInteger(busLineId) ||
        !Number.isInteger(dayOfWeek) ||
        dayOfWeek < 0 ||
        dayOfWeek > 6 ||
        !startTime ||
        !endTime
      ) {
        return res.status(400).json({ error: "invalid_schedule" });
      }

      const result = await db.query(
        `
      UPDATE transit.schedules
      SET bus_line_id = $2, start_time = $3::time, end_time = $4::time,
          day_of_week = $5, updated_at = NOW()
      WHERE id = $1
      RETURNING id, bus_line_id, start_time, end_time, status, day_of_week
    `,
        [scheduleId, busLineId, startTime, endTime, dayOfWeek],
      );
      if (result.rows.length === 0)
        return res.status(404).json({ error: "schedule_not_found" });
      res.json({ schedule: result.rows[0] });
    } catch (err) {
      console.error("PUT /admin/weekly-schedules error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.put(
  "/admin/weekly-schedules/:scheduleId/shift",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const scheduleId = Number(req.params.scheduleId);
      const driverId = req.body?.driverId ? Number(req.body.driverId) : null;
      if (!Number.isInteger(scheduleId))
        return res.status(400).json({ error: "invalid_schedule_id" });
      await db.query("DELETE FROM transit.shifts WHERE schedule_id = $1", [
        scheduleId,
      ]);
      if (driverId) {
        await db.query(
          "INSERT INTO transit.shifts (schedule_id, driver_id) VALUES ($1, $2)",
          [scheduleId, driverId],
        );
      }
      res.json({ scheduleId, driverId });
    } catch (err) {
      console.error("PUT /admin/weekly-schedules/:id/shift error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.delete(
  "/admin/weekly-schedules/:scheduleId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const scheduleId = Number(req.params.scheduleId);
      if (!Number.isInteger(scheduleId))
        return res.status(400).json({ error: "invalid_schedule_id" });
      const result = await db.query(
        "DELETE FROM transit.schedules WHERE id = $1 RETURNING id",
        [scheduleId],
      );
      if (result.rows.length === 0)
        return res.status(404).json({ error: "schedule_not_found" });
      res.json({ success: true, scheduleId });
    } catch (err) {
      console.error("DELETE /admin/weekly-schedules error:", err);
      res.status(500).json({ error: "internal_error" });
    }
  },
);

app.get(
  "/admin/schedules",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const templatesOnly =
        String(
          req.query.templates || req.query.includeTemplates || "",
        ).toLowerCase() === "true" ||
        String(req.query.templates || req.query.includeTemplates || "") === "1";

      if (DEV_MOCK) {
        const routeStopsByLine = new Map();
        for (const routeStop of _mock.routeStops || []) {
          const busLineId = Number(routeStop.busLineId);
          if (!routeStopsByLine.has(busLineId)) {
            routeStopsByLine.set(busLineId, []);
          }
          routeStopsByLine.get(busLineId).push({
            stop_id: routeStop.stopId,
            stop_order: routeStop.stopOrder,
          });
        }

        const rawSchedules = (_mock.schedules || []).map((s) => {
          const busLine = _mock.busLines.find((bl) => bl.id === s.busLineId);
          const bus = _mock.fleetBuses.find((b) => b.id === s.busId);
          return {
            ...s,
            busLineId: s.busLineId,
            busId: s.busId,
            startTime: s.startTime,
            endTime: s.endTime,
            weekdays: s.weekdays || [],
            status: s.status,
            lineNumber: busLine?.lineNumber || 0,
            busName: bus?.name || "Unknown Bus",
            driverId: s.driverId || null,
            estimatedDurationMinutes: busLine?.estimatedDurationMinutes || 60,
          };
        });

        const schedules = (
          templatesOnly
            ? rawSchedules
            : expandRecurringScheduleRows(rawSchedules)
        )
          .filter((row) =>
            scheduleMatchesFilters(
              row,
              parseScheduleFilters(req.query),
              routeStopsByLine,
            ),
          )
          .map((s) => ({
            ...s,
            departureTimes: calculateDepartureTimes(
              s.startTime,
              s.busLineId,
              _mock,
            ),
          }))
          .sort((a, b) => new Date(a.startTime) - new Date(b.startTime));

        return res.json({ schedules });
      }

      const hasWeekdaysColumn = await db.query(`
      SELECT 1 FROM information_schema.columns 
      WHERE table_schema='transit' AND table_name='schedules' AND column_name='weekdays'
    `);

      const baseSelect = `
      SELECT 
        s.id,
        s.bus_line_id,
        s.bus_id,
        s.driver_id,
        s.start_time,
        s.end_time,
        s.status,
        s.created_at,
        bl.line_number,
        bl.estimated_duration_minutes,
        b.name as bus_name,
        b.license_plate,
        TRIM(COALESCE(e.firstname, '') || ' ' || COALESCE(e.lastname, '')) as driver_name`;

      const result =
        hasWeekdaysColumn.rows.length > 0
          ? await db.query(`${baseSelect}, s.weekdays as weekdays
          FROM transit.schedules s
          LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          LEFT JOIN fleet.bus b ON s.bus_id = b.id
          LEFT JOIN workers.employees e ON s.driver_id = e.id
          ORDER BY s.start_time DESC`)
          : await db.query(`${baseSelect}, NULL as weekdays
          FROM transit.schedules s
          LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          LEFT JOIN fleet.bus b ON s.bus_id = b.id
          LEFT JOIN workers.employees e ON s.driver_id = e.id
          ORDER BY s.start_time DESC`);

      const lineIds = Array.from(
        new Set(
          result.rows
            .map((row) => Number(row.bus_line_id))
            .filter(Number.isFinite),
        ),
      );

      const routeStopsByLine = new Map();
      if (lineIds.length > 0) {
        const routeStopsResult = await db.query(
          `
        SELECT
          rs.bus_line_id,
          rs.stop_id,
          rs.stop_order,
          rs.estimated_arrival_minutes,
          s.name AS stop_name
        FROM transit.route_stops rs
        JOIN transit.stops s ON s.id = rs.stop_id
        WHERE rs.bus_line_id = ANY($1::int[])
        ORDER BY rs.bus_line_id ASC, rs.stop_order ASC
      `,
          [lineIds],
        );

        for (const row of routeStopsResult.rows) {
          const busLineId = Number(row.bus_line_id);
          if (!routeStopsByLine.has(busLineId)) {
            routeStopsByLine.set(busLineId, []);
          }
          routeStopsByLine.get(busLineId).push(row);
        }
      }

      const filters = parseScheduleFilters(req.query);
      const rowSource = templatesOnly
        ? result.rows
        : expandRecurringScheduleRows(result.rows);
      const expandedSchedules = rowSource.filter((row) =>
        scheduleMatchesFilters(row, filters, routeStopsByLine),
      );

      const schedules = expandedSchedules
        .map((row) => mapAdminScheduleRow(row, routeStopsByLine))
        .sort((a, b) => new Date(a.startTime) - new Date(b.startTime));

      res.json({ schedules });
    } catch (err) {
      console.error("GET /admin/schedules error:", err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/schedules",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { busLineId, busId, driverId, startTime, weekdays } = req.body;

      if (!busLineId || !busId || !startTime) {
        return res.status(400).json({
          error:
            "missing_required_fields: busLineId, busId, startTime required",
        });
      }

      // Validate weekdays - should be array of day numbers (0-6) or empty for single schedule
      const scheduleWeekdays =
        Array.isArray(weekdays) && weekdays.length > 0
          ? weekdays.map((w) => Number(w)).filter((w) => w >= 0 && w <= 6)
          : [];

      if (DEV_MOCK) {
        if (!_mock.schedules) _mock.schedules = [];

        // Find the bus line to get duration
        const busLine = _mock.busLines.find((bl) => bl.id == busLineId);
        if (!busLine) {
          return res.status(404).json({ error: "bus_line_not_found" });
        }

        const startDate = new Date(startTime);
        const endDate = new Date(startDate);
        endDate.setMinutes(
          endDate.getMinutes() + (busLine.estimatedDurationMinutes || 60),
        );

        // Calculate departure times for stops
        const departureTimes = calculateDepartureTimes(
          startTime,
          Number(busLineId),
          _mock,
        );

        const schedule = {
          id: _mock.nextScheduleId || 1,
          busLineId,
          busId,
          driverId: driverId ? Number(driverId) : null,
          startTime,
          endTime: endDate.toISOString(),
          weekdays: scheduleWeekdays,
          departureTimes,
          status: "planned",
          createdAt: new Date().toISOString(),
        };
        _mock.nextScheduleId = (_mock.nextScheduleId || 1) + 1;
        _mock.schedules.push(schedule);
        return res.status(201).json({ schedule });
      }

      // Database mode (production)
      const busLine = await db.query(
        "SELECT estimated_duration_minutes FROM transit.bus_lines WHERE id = $1",
        [busLineId],
      );
      if (!busLine.rows[0]) {
        return res.status(404).json({ error: "bus_line_not_found" });
      }

      const startDate = new Date(startTime);
      const endDate = new Date(startDate);
      endDate.setMinutes(
        endDate.getMinutes() +
          (busLine.rows[0].estimated_duration_minutes || 60),
      );

      // Check if weekdays column exists before including it in INSERT
      const hasWeekdaysColumn = await db.query(`
      SELECT 1 FROM information_schema.columns 
      WHERE table_schema='transit' AND table_name='schedules' AND column_name='weekdays'
    `);

      let result;
      if (hasWeekdaysColumn.rows.length > 0) {
        result = await db.query(
          `
        WITH next_id AS (
          SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules
        )
        INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status, weekdays)
        SELECT next_id.id, $1, $2, $3, $4, $5, 'planned', $6
        FROM next_id
        RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, weekdays, created_at
      `,
          [
            busLineId,
            busId,
            driverId || null,
            startTime,
            endDate.toISOString(),
            JSON.stringify(scheduleWeekdays),
          ],
        );
      } else {
        result = await db.query(
          `
        WITH next_id AS (
          SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules
        )
        INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status)
        SELECT next_id.id, $1, $2, $3, $4, $5, 'planned'
        FROM next_id
        RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, created_at
      `,
          [
            busLineId,
            busId,
            driverId || null,
            startTime,
            endDate.toISOString(),
          ],
        );
      }

      const schedule = result.rows[0];
      const departureTimes = calculateDepartureTimes(
        startTime,
        busLineId,
        _mock,
      );

      const weekdaysResult = parseWeekdaysValue(schedule.weekdays);

      res.status(201).json({
        schedule: {
          id: Number(schedule.id),
          busLineId: Number(schedule.bus_line_id),
          busId: Number(schedule.bus_id),
          driverId:
            schedule.driver_id !== null && schedule.driver_id !== undefined
              ? Number(schedule.driver_id)
              : null,
          startTime: schedule.start_time,
          endTime: schedule.end_time,
          weekdays: weekdaysResult,
          departureTimes,
          status: schedule.status,
          createdAt: schedule.created_at,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.put(
  "/admin/schedules/:scheduleId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { scheduleId } = req.params;
      const { busLineId, busId, driverId, startTime, weekdays } = req.body;

      if (!scheduleId || !Number.isFinite(Number(scheduleId))) {
        return res.status(400).json({ error: "invalid_schedule_id" });
      }

      if (!busLineId || !busId || !startTime) {
        return res.status(400).json({
          error:
            "missing_required_fields: busLineId, busId, startTime required",
        });
      }

      const scheduleWeekdays =
        Array.isArray(weekdays) && weekdays.length > 0
          ? weekdays.map((w) => Number(w)).filter((w) => w >= 0 && w <= 6)
          : [];

      if (DEV_MOCK) {
        const index = (_mock.schedules || []).findIndex(
          (s) => Number(s.id) === Number(scheduleId),
        );
        if (index === -1) {
          return res.status(404).json({ error: "schedule_not_found" });
        }

        const busLine = _mock.busLines.find((bl) => bl.id == busLineId);
        if (!busLine) {
          return res.status(404).json({ error: "bus_line_not_found" });
        }

        const startDate = new Date(startTime);
        const endDate = new Date(startDate);
        endDate.setMinutes(
          endDate.getMinutes() + (busLine.estimatedDurationMinutes || 60),
        );

        _mock.schedules[index] = {
          ..._mock.schedules[index],
          busLineId: Number(busLineId),
          busId: Number(busId),
          driverId: driverId ? Number(driverId) : null,
          startTime,
          endTime: endDate.toISOString(),
          weekdays: scheduleWeekdays,
        };

        return res.json({ schedule: _mock.schedules[index] });
      }

      const existingResult = await db.query(
        `
      SELECT id, status
      FROM transit.schedules
      WHERE id = $1
    `,
        [scheduleId],
      );

      if (existingResult.rows.length === 0) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      const busLine = await db.query(
        "SELECT estimated_duration_minutes FROM transit.bus_lines WHERE id = $1",
        [busLineId],
      );
      if (!busLine.rows[0]) {
        return res.status(404).json({ error: "bus_line_not_found" });
      }

      const startDate = new Date(startTime);
      const endDate = new Date(startDate);
      endDate.setMinutes(
        endDate.getMinutes() +
          (busLine.rows[0].estimated_duration_minutes || 60),
      );

      const hasWeekdaysColumn = await db.query(`
      SELECT 1 FROM information_schema.columns
      WHERE table_schema='transit' AND table_name='schedules' AND column_name='weekdays'
    `);

      let result;
      if (hasWeekdaysColumn.rows.length > 0) {
        result = await db.query(
          `
        UPDATE transit.schedules
        SET
          bus_line_id = $2,
          bus_id = $3,
          driver_id = $4,
          start_time = $5,
          end_time = $6,
          weekdays = $7,
          updated_at = NOW()
        WHERE id = $1
        RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, weekdays, created_at
      `,
          [
            scheduleId,
            busLineId,
            busId,
            driverId || null,
            startTime,
            endDate.toISOString(),
            JSON.stringify(scheduleWeekdays),
          ],
        );
      } else {
        result = await db.query(
          `
        UPDATE transit.schedules
        SET
          bus_line_id = $2,
          bus_id = $3,
          driver_id = $4,
          start_time = $5,
          end_time = $6,
          updated_at = NOW()
        WHERE id = $1
        RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, created_at
      `,
          [
            scheduleId,
            busLineId,
            busId,
            driverId || null,
            startTime,
            endDate.toISOString(),
          ],
        );
      }

      const schedule = result.rows[0];
      return res.json({
        schedule: {
          id: Number(schedule.id),
          busLineId: Number(schedule.bus_line_id),
          busId: Number(schedule.bus_id),
          driverId:
            schedule.driver_id !== null && schedule.driver_id !== undefined
              ? Number(schedule.driver_id)
              : null,
          startTime: schedule.start_time,
          endTime: schedule.end_time,
          weekdays: parseWeekdaysValue(schedule.weekdays),
          status: schedule.status,
          createdAt: schedule.created_at,
        },
      });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

app.post(
  "/admin/schedules/bulk",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    const requestedSchedules = Array.isArray(req.body?.schedules)
      ? req.body.schedules
      : [];

    if (requestedSchedules.length === 0) {
      return res
        .status(400)
        .json({ error: "missing_required_fields: schedules array required" });
    }

    const normalizedSchedules = requestedSchedules.map((schedule, index) => {
      const busLineId = Number(schedule?.busLineId);
      const busId = Number(schedule?.busId);
      const driverId =
        schedule?.driverId !== null &&
        schedule?.driverId !== undefined &&
        schedule?.driverId !== ""
          ? Number(schedule.driverId)
          : null;
      const startTime = schedule?.startTime ? String(schedule.startTime) : "";
      const weekdays =
        Array.isArray(schedule?.weekdays) && schedule.weekdays.length > 0
          ? schedule.weekdays
              .map((day) => Number(day))
              .filter((day) => day >= 0 && day <= 6)
          : [];

      if (
        !Number.isFinite(busLineId) ||
        !Number.isFinite(busId) ||
        !startTime
      ) {
        throw new Error(`invalid_schedule_entry:${index}`);
      }

      return { busLineId, busId, driverId, startTime, weekdays };
    });

    try {
      if (DEV_MOCK) {
        if (!_mock.schedules) _mock.schedules = [];

        const createdSchedules = [];

        for (const entry of normalizedSchedules) {
          const busLine = _mock.busLines.find((bl) => bl.id == entry.busLineId);
          if (!busLine) {
            return res.status(404).json({ error: "bus_line_not_found" });
          }

          const startDate = new Date(entry.startTime);
          const endDate = new Date(startDate);
          endDate.setMinutes(
            endDate.getMinutes() + (busLine.estimatedDurationMinutes || 60),
          );

          const departureTimes = calculateDepartureTimes(
            entry.startTime,
            Number(entry.busLineId),
            _mock,
          );

          const schedule = {
            id: _mock.nextScheduleId || 1,
            busLineId: entry.busLineId,
            busId: entry.busId,
            driverId: entry.driverId,
            startTime: entry.startTime,
            endTime: endDate.toISOString(),
            weekdays: entry.weekdays,
            departureTimes,
            status: "planned",
            createdAt: new Date().toISOString(),
          };

          _mock.nextScheduleId = (_mock.nextScheduleId || 1) + 1;
          _mock.schedules.push(schedule);
          createdSchedules.push(schedule);
        }

        return res.status(201).json({
          createdCount: createdSchedules.length,
          schedules: createdSchedules,
        });
      }

      const dbClient = await db.pool.connect();
      try {
        await dbClient.query("BEGIN");

        const hasWeekdaysColumn = await dbClient.query(`
        SELECT 1 FROM information_schema.columns
        WHERE table_schema='transit' AND table_name='schedules' AND column_name='weekdays'
      `);

        const createdSchedules = [];

        for (const entry of normalizedSchedules) {
          const busLine = await dbClient.query(
            "SELECT estimated_duration_minutes FROM transit.bus_lines WHERE id = $1",
            [entry.busLineId],
          );
          if (!busLine.rows[0]) {
            throw new Error("bus_line_not_found");
          }

          const startDate = new Date(entry.startTime);
          const endDate = new Date(startDate);
          endDate.setMinutes(
            endDate.getMinutes() +
              (busLine.rows[0].estimated_duration_minutes || 60),
          );

          let result;
          if (hasWeekdaysColumn.rows.length > 0) {
            result = await dbClient.query(
              `
            WITH next_id AS (
              SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules
            )
            INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status, weekdays)
            SELECT next_id.id, $1, $2, $3, $4, $5, 'planned', $6
            FROM next_id
            RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, weekdays, created_at
          `,
              [
                entry.busLineId,
                entry.busId,
                entry.driverId,
                entry.startTime,
                endDate.toISOString(),
                JSON.stringify(entry.weekdays),
              ],
            );
          } else {
            result = await dbClient.query(
              `
            WITH next_id AS (
              SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules
            )
            INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status)
            SELECT next_id.id, $1, $2, $3, $4, $5, 'planned'
            FROM next_id
            RETURNING id, bus_line_id, bus_id, driver_id, start_time, end_time, status, created_at
          `,
              [
                entry.busLineId,
                entry.busId,
                entry.driverId,
                entry.startTime,
                endDate.toISOString(),
              ],
            );
          }

          const schedule = result.rows[0];
          createdSchedules.push({
            id: Number(schedule.id),
            busLineId: Number(schedule.bus_line_id),
            busId: Number(schedule.bus_id),
            driverId:
              schedule.driver_id !== null && schedule.driver_id !== undefined
                ? Number(schedule.driver_id)
                : null,
            startTime: schedule.start_time,
            endTime: schedule.end_time,
            weekdays: parseWeekdaysValue(schedule.weekdays),
            status: schedule.status,
            createdAt: schedule.created_at,
          });
        }

        await dbClient.query("COMMIT");
        return res.status(201).json({
          createdCount: createdSchedules.length,
          schedules: createdSchedules,
        });
      } catch (err) {
        await dbClient.query("ROLLBACK");
        throw err;
      } finally {
        dbClient.release();
      }
    } catch (err) {
      console.error(err);
      const errorMessage =
        err.message === "bus_line_not_found"
          ? "bus_line_not_found"
          : err.message.startsWith("invalid_schedule_entry:")
            ? err.message
            : "internal_error";
      const statusCode =
        errorMessage === "bus_line_not_found"
          ? 404
          : errorMessage.startsWith("invalid_schedule_entry:")
            ? 400
            : 500;
      res
        .status(statusCode)
        .json({ error: errorMessage, details: err.message });
    }
  },
);

app.delete(
  "/admin/schedules/:scheduleId",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { scheduleId } = req.params;

      if (!scheduleId || !Number.isFinite(Number(scheduleId))) {
        return res.status(400).json({ error: "invalid_schedule_id" });
      }

      if (DEV_MOCK) {
        if (!_mock.schedules) _mock.schedules = [];
        const index = _mock.schedules.findIndex(
          (s) => Number(s.id) === Number(scheduleId),
        );
        if (index === -1) {
          return res.status(404).json({ error: "schedule_not_found" });
        }
        const deleted = _mock.schedules.splice(index, 1)[0];
        return res.json({ success: true, schedule: deleted });
      }

      const result = await db.query(
        `DELETE FROM transit.schedules WHERE id = $1 RETURNING id`,
        [scheduleId],
      );

      if (result.rows.length === 0) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      res.json({ success: true, schedule: { id: Number(result.rows[0].id) } });
    } catch (err) {
      console.error(err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// PUBLIC - Get schedules (for public timetable)
// ============================================
app.get("/schedules", async (req, res) => {
  try {
    const filters = parseScheduleFilters(req.query, {
      statuses: ["planned", "active"],
    });

    if (DEV_MOCK) {
      const routeStopsByLine = new Map();
      for (const routeStop of _mock.routeStops || []) {
        const busLineId = Number(routeStop.busLineId);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }
        routeStopsByLine.get(busLineId).push({
          stop_id: routeStop.stopId,
          stop_order: routeStop.stopOrder,
        });
      }

      const schedules = expandRecurringScheduleRows(
        (_mock.schedules || []).map((s) => {
          const busLine = _mock.busLines.find((bl) => bl.id === s.busLineId);
          const bus = _mock.fleetBuses.find((b) => b.id === s.busId);
          return {
            id: s.id,
            busLineId: s.busLineId,
            busId: s.busId,
            startTime: s.startTime,
            endTime: s.endTime,
            weekdays: s.weekdays || [],
            status: s.status,
            lineNumber: busLine?.lineNumber || 0,
            busName: bus?.name || "Unknown Bus",
            driverId: null,
            estimatedDurationMinutes: busLine?.estimatedDurationMinutes || 60,
          };
        }),
      ).filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine));

      return res.json({ schedules });
    }

    let query = `
      SELECT 
        s.id,
        s.bus_line_id,
        s.bus_id,
        s.driver_id,
        s.start_time,
        s.end_time,
        s.weekdays,
        s.status,
        bl.line_number,
        b.name as bus_name,
        bl.estimated_duration_minutes
      FROM transit.schedules s
      LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
      LEFT JOIN fleet.bus b ON s.bus_id = b.id
      WHERE 1 = 1
    `;

    const params = [];

    if (filters.statuses.length > 0) {
      query += ` AND s.status = ANY($${params.length + 1}::text[])`;
      params.push(filters.statuses);
    }

    if (filters.busLineId !== null) {
      query += ` AND s.bus_line_id = $${params.length + 1}`;
      params.push(filters.busLineId);
    }

    if (filters.busId !== null) {
      query += ` AND s.bus_id = $${params.length + 1}`;
      params.push(filters.busId);
    }

    if (filters.driverId !== null) {
      query += ` AND s.driver_id = $${params.length + 1}`;
      params.push(filters.driverId);
    }

    query += ` ORDER BY s.start_time ASC`;

    const result = await db.query(query, params);

    const lineIds = Array.from(
      new Set(
        result.rows
          .map((row) => Number(row.bus_line_id))
          .filter(Number.isFinite),
      ),
    );
    const routeStopsByLine = new Map();

    if (filters.stopId !== null && lineIds.length > 0) {
      const routeStopsResult = await db.query(
        `
        SELECT
          rs.bus_line_id,
          rs.stop_id,
          rs.stop_order
        FROM transit.route_stops rs
        WHERE rs.bus_line_id = ANY($1::int[])
        ORDER BY rs.bus_line_id ASC, rs.stop_order ASC
      `,
        [lineIds],
      );

      for (const row of routeStopsResult.rows) {
        const busLineId = Number(row.bus_line_id);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }
        routeStopsByLine.get(busLineId).push(row);
      }
    }

    const schedules = expandRecurringScheduleRows(result.rows)
      .filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine))
      .map((row) => ({
        id: Number(row.id),
        busLineId: Number(row.bus_line_id),
        busId: Number(row.bus_id),
        // Hide driver from public API responses
        driverId: null,
        startTime: row.start_time,
        endTime: row.end_time,
        weekdays: row.weekdays
          ? typeof row.weekdays === "string"
            ? JSON.parse(row.weekdays)
            : row.weekdays
          : [],
        status: row.status,
        lineNumber: row.line_number,
        busName: row.bus_name,
        estimatedDurationMinutes:
          Number(row.estimated_duration_minutes) || null,
        isRecurringInstance: row.is_recurring_instance || false,
        templateId: row.template_id || null,
      }));

    res.json({ schedules });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

app.get("/schedules/overview", async (req, res) => {
  try {
    const filters = parseScheduleFilters(req.query, {
      statuses: ["planned", "active"],
    });
    const overviewDateKey = filters.date || null;

    if (DEV_MOCK) {
      const routeStopsByLine = new Map();

      for (const routeStop of _mock.routeStops || []) {
        const busLineId = Number(routeStop.busLineId);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }

        routeStopsByLine.get(busLineId).push({
          bus_line_id: busLineId,
          stop_id: routeStop.stopId,
          stop_order: routeStop.stopOrder,
          estimated_arrival_minutes: routeStop.estimatedArrivalMinutes,
          stop_name: routeStop.name || "",
        });
      }

      const baseRows = (_mock.schedules || []).map((schedule) => {
        const busLine = _mock.busLines.find(
          (line) => Number(line.id) === Number(schedule.busLineId),
        );
        const bus = _mock.fleetBuses.find(
          (vehicle) => Number(vehicle.id) === Number(schedule.busId),
        );
        const driver = _mock.drivers.find(
          (person) => Number(person.id) === Number(schedule.driverId),
        );

        return {
          id: schedule.id,
          busLineId: schedule.busLineId,
          busId: schedule.busId,
          driverId: schedule.driverId ?? null,
          driverName: driver ? driver.name : null,
          startTime: schedule.startTime,
          endTime: schedule.endTime,
          weekdays: schedule.weekdays || [],
          status: schedule.status,
          lineNumber: busLine?.lineNumber || 0,
          busName: bus?.name || "Unknown Bus",
          licensePlate: bus?.licensePlate || "",
          createdAt: schedule.createdAt,
        };
      });

      const schedules = mapRecurringOccurrenceRows(
        baseRows,
        overviewDateKey,
        routeStopsByLine,
      ).filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine));

      return res.json({
        date: overviewDateKey,
        summary: {
          total: schedules.length,
          recurring: schedules.filter(
            (schedule) => schedule.scheduleType === "recurring",
          ).length,
          oneTime: schedules.filter(
            (schedule) => schedule.scheduleType === "one_time",
          ).length,
        },
        schedules,
      });
    }

    const hasWeekdaysColumn = await db.query(`
      SELECT 1 FROM information_schema.columns
      WHERE table_schema = 'transit' AND table_name = 'schedules' AND column_name = 'weekdays'
    `);

    const baseSelect = `
      SELECT
        s.id,
        s.bus_line_id AS "busLineId",
        s.bus_id AS "busId",
        s.driver_id AS "driverId",
        s.start_time AS "startTime",
        s.end_time AS "endTime",
        s.status,
        s.created_at AS "createdAt",
        bl.line_number AS "lineNumber",
        bl.estimated_duration_minutes AS "estimatedDurationMinutes",
        b.name AS "busName",
        b.license_plate AS "licensePlate",
        TRIM(COALESCE(e.firstname, '') || ' ' || COALESCE(e.lastname, '')) AS "driverName"`;

    const result =
      hasWeekdaysColumn.rows.length > 0
        ? await db.query(
            `${baseSelect}, s.weekdays AS weekdays
          FROM transit.schedules s
          LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          LEFT JOIN fleet.bus b ON s.bus_id = b.id
          LEFT JOIN workers.employees e ON s.driver_id = e.id
          WHERE s.status = ANY($1::text[])
          ORDER BY s.start_time ASC`,
            [filters.statuses],
          )
        : await db.query(
            `${baseSelect}, NULL AS weekdays
          FROM transit.schedules s
          LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
          LEFT JOIN fleet.bus b ON s.bus_id = b.id
          LEFT JOIN workers.employees e ON s.driver_id = e.id
          WHERE s.status = ANY($1::text[])
          ORDER BY s.start_time ASC`,
            [filters.statuses],
          );

    const lineIds = Array.from(
      new Set(
        result.rows.map((row) => Number(row.busLineId)).filter(Number.isFinite),
      ),
    );

    const routeStopsByLine = new Map();

    if (lineIds.length > 0) {
      const routeStopsResult = await db.query(
        `
        SELECT
          rs.bus_line_id,
          rs.stop_id,
          rs.stop_order,
          rs.estimated_arrival_minutes,
          s.name AS stop_name
        FROM transit.route_stops rs
        JOIN transit.stops s ON s.id = rs.stop_id
        WHERE rs.bus_line_id = ANY($1::int[])
        ORDER BY rs.bus_line_id ASC, rs.stop_order ASC
      `,
        [lineIds],
      );

      for (const row of routeStopsResult.rows) {
        const busLineId = Number(row.bus_line_id);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }

        routeStopsByLine.get(busLineId).push(row);
      }
    }

    let schedules = [];
    if (filters.fromDate && filters.toDate) {
      schedules = materializeScheduleRowsInRange(
        result.rows,
        filters.fromDate,
        filters.toDate,
        routeStopsByLine,
      ).filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine));
    } else {
      schedules = mapRecurringOccurrenceRows(
        result.rows,
        overviewDateKey,
        routeStopsByLine,
      ).filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine));
    }

    // Enrich schedules with live progress for the occurrence date(s)
    if (!DEV_MOCK && schedules.length > 0) {
      const scheduleIds = [
        ...new Set(schedules.map((s) => Number(s.id)).filter(Number.isFinite)),
      ];
      const occurrenceDates = [
        ...new Set(
          schedules.map((s) => toDateKey(s.startTime)).filter(Boolean),
        ),
      ];

      if (scheduleIds.length > 0 && occurrenceDates.length > 0) {
        const progressRes = await db.query(
          `
          SELECT schedule_id, scheduled_passed_date, stop_order, actual_passed_at, scheduled_passed_at, delay_minutes
          FROM transit.schedule_stop_progress
          WHERE schedule_id = ANY($1::int[]) AND scheduled_passed_date = ANY($2::date[])
          ORDER BY schedule_id ASC, scheduled_passed_date ASC, actual_passed_at ASC
        `,
          [scheduleIds, occurrenceDates],
        );

        const progressByKey = new Map();
        for (const row of progressRes.rows) {
          const key = `${row.schedule_id}|${row.scheduled_passed_date}`;
          if (!progressByKey.has(key)) progressByKey.set(key, []);
          progressByKey.get(key).push(row);
        }

        schedules = schedules.map((s) => {
          const key = `${s.id}|${toDateKey(s.startTime)}`;
          const progRows = progressByKey.get(key) || [];
          const totalStops = (routeStopsByLine.get(Number(s.busLineId)) || [])
            .length;
          const passedStops = progRows.length;
          let currentDelayMinutes = null;
          if (progRows.length > 0) {
            const latest = progRows[progRows.length - 1];
            currentDelayMinutes =
              Number(latest.delay_minutes ?? latest.delay_minutes) || null;
          }

          const statusOverride =
            passedStops >= totalStops && totalStops > 0
              ? "completed"
              : passedStops > 0
                ? "in_progress"
                : s.status;

          return {
            ...s,
            status: statusOverride,
            passedStops,
            totalStops,
            currentDelayMinutes,
          };
        });
      }
    } else if (DEV_MOCK && schedules.length > 0) {
      const mockProgress = _mock.scheduleStopProgress || [];
      const progressByKey = new Map();
      for (const p of mockProgress) {
        const key = `${p.scheduleId}|${p.scheduledPassedDate}`;
        if (!progressByKey.has(key)) progressByKey.set(key, []);
        progressByKey.get(key).push(p);
      }

      schedules = schedules.map((s) => {
        const key = `${s.id}|${toDateKey(s.startTime)}`;
        const progRows = progressByKey.get(key) || [];
        const totalStops = (routeStopsByLine.get(Number(s.busLineId)) || [])
          .length;
        const passedStops = progRows.length;
        const latest =
          progRows.length > 0 ? progRows[progRows.length - 1] : null;
        const currentDelayMinutes = latest
          ? Number(latest.delayMinutes) || 0
          : null;
        const statusOverride =
          passedStops >= totalStops && totalStops > 0
            ? "completed"
            : passedStops > 0
              ? "in_progress"
              : s.status;
        return {
          ...s,
          status: statusOverride,
          passedStops,
          totalStops,
          currentDelayMinutes,
        };
      });
    }

    res.json({
      date: overviewDateKey,
      summary: {
        total: schedules.length,
        recurring: schedules.filter(
          (schedule) => schedule.scheduleType === "recurring",
        ).length,
        oneTime: schedules.filter(
          (schedule) => schedule.scheduleType === "one_time",
        ).length,
      },
      schedules,
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// PUBLIC - Get all recurring schedule templates (no date filtering)
// ============================================
app.get("/schedules/recurring", async (req, res) => {
  try {
    const filters = parseScheduleFilters(req.query);

    if (DEV_MOCK) {
      const routeStopsByLine = new Map();

      for (const routeStop of _mock.routeStops || []) {
        const busLineId = Number(routeStop.busLineId);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }

        routeStopsByLine.get(busLineId).push({
          bus_line_id: busLineId,
          stop_id: routeStop.stopId,
          stop_order: routeStop.stopOrder,
          estimated_arrival_minutes: routeStop.estimatedArrivalMinutes,
          stop_name: routeStop.name || "",
        });
      }

      const baseRows = (_mock.schedules || [])
        .filter(
          (schedule) =>
            Array.isArray(schedule.weekdays) && schedule.weekdays.length > 0,
        )
        .map((schedule) => {
          const busLine = _mock.busLines.find(
            (line) => Number(line.id) === Number(schedule.busLineId),
          );
          const bus = _mock.fleetBuses.find(
            (vehicle) => Number(vehicle.id) === Number(schedule.busId),
          );
          const driver = _mock.drivers.find(
            (person) => Number(person.id) === Number(schedule.driverId),
          );

          return {
            id: schedule.id,
            busLineId: schedule.busLineId,
            busId: schedule.busId,
            driverId: schedule.driverId ?? null,
            driverName: driver ? driver.name : null,
            startTime: schedule.startTime,
            endTime: schedule.endTime,
            weekdays: schedule.weekdays || [],
            lineNumber: busLine?.lineNumber || 0,
            busName: bus?.name || "Unknown Bus",
            licensePlate: bus?.licensePlate || "",
            createdAt: schedule.createdAt,
          };
        });

      const schedules = baseRows
        .filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine))
        .map((row) => {
          const materialized = materializeScheduleOverviewRow(
            row,
            null,
            routeStopsByLine,
          );
          return {
            ...materialized,
            status: undefined,
          };
        });

      return res.json({ schedules });
    }

    const hasWeekdaysColumn = await db.query(`
      SELECT 1 FROM information_schema.columns
      WHERE table_schema = 'transit' AND table_name = 'schedules' AND column_name = 'weekdays'
    `);

    if (hasWeekdaysColumn.rows.length === 0) {
      return res.json({ schedules: [] });
    }

    const result = await db.query(`
      SELECT
        s.id,
        s.bus_line_id AS "busLineId",
        s.bus_id AS "busId",
        s.driver_id AS "driverId",
        s.start_time AS "startTime",
        s.end_time AS "endTime",
        s.weekdays,
        bl.line_number AS "lineNumber",
        b.name AS "busName",
        b.license_plate AS "licensePlate",
        TRIM(COALESCE(e.firstname, '') || ' ' || COALESCE(e.lastname, '')) AS "driverName",
        s.created_at AS "createdAt"
      FROM transit.schedules s
      LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
      LEFT JOIN fleet.bus b ON s.bus_id = b.id
      LEFT JOIN workers.employees e ON s.driver_id = e.id
      WHERE s.weekdays IS NOT NULL
    `);

    const lineIds = Array.from(
      new Set(
        result.rows.map((row) => Number(row.busLineId)).filter(Number.isFinite),
      ),
    );
    const routeStopsByLine = new Map();

    if (lineIds.length > 0) {
      const routeStopsResult = await db.query(
        `
        SELECT
          rs.bus_line_id,
          rs.stop_id,
          rs.stop_order,
          rs.estimated_arrival_minutes,
          s.name AS stop_name
        FROM transit.route_stops rs
        JOIN transit.stops s ON s.id = rs.stop_id
        WHERE rs.bus_line_id = ANY($1::int[])
        ORDER BY rs.bus_line_id ASC, rs.stop_order ASC
      `,
        [lineIds],
      );

      for (const row of routeStopsResult.rows) {
        const busLineId = Number(row.bus_line_id);
        if (!routeStopsByLine.has(busLineId)) {
          routeStopsByLine.set(busLineId, []);
        }
        routeStopsByLine.get(busLineId).push(row);
      }
    }

    const schedules = result.rows
      .filter((row) => scheduleMatchesFilters(row, filters, routeStopsByLine))
      .map((row) => {
        const schedule = materializeScheduleOverviewRow(
          row,
          null,
          routeStopsByLine,
        );
        delete schedule.status;
        return schedule;
      });

    res.json({ schedules });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

app.get("/schedules/:scheduleId", async (req, res) => {
  try {
    const { scheduleId } = req.params;

    if (DEV_MOCK) {
      const schedule = (_mock.schedules || []).find(
        (s) => Number(s.id) === Number(scheduleId),
      );
      if (!schedule) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      // Enrich with bus line and fleet bus info
      const busLine = _mock.busLines.find((bl) => bl.id === schedule.busLineId);
      const bus = _mock.fleetBuses.find((b) => b.id === schedule.busId);

      return res.json({
        schedule: {
          id: schedule.id,
          busLineId: schedule.busLineId,
          busId: schedule.busId,
          startTime: schedule.startTime,
          endTime: schedule.endTime,
          weekdays: schedule.weekdays || [],
          status: schedule.status,
          lineNumber: busLine?.lineNumber || 0,
          busName: bus?.name || "Unknown Bus",
        },
      });
    }

    const result = await db.query(
      `
      SELECT 
        s.id,
        s.bus_line_id,
        s.bus_id,
        s.start_time,
        s.end_time,
        s.status,
        s.weekdays,
        bl.line_number,
        bl.start_stop,
        bl.end_stop,
        b.name as bus_name,
        b.license_plate
      FROM transit.schedules s
      LEFT JOIN transit.bus_lines bl ON s.bus_line_id = bl.id
      LEFT JOIN fleet.bus b ON s.bus_id = b.id
      WHERE s.id = $1
    `,
      [scheduleId],
    );

    if (result.rows.length === 0) {
      return res.status(404).json({ error: "schedule_not_found" });
    }

    const row = result.rows[0];
    const weekdays = parseWeekdaysValue(row.weekdays);

    res.json({
      schedule: {
        id: Number(row.id),
        busLineId: Number(row.bus_line_id),
        busId: Number(row.bus_id),
        startTime: row.start_time,
        endTime: row.end_time,
        status: row.status,
        weekdays: weekdays,
        lineNumber: row.line_number,
        startStop: row.start_stop,
        endStop: row.end_stop,
        busName: row.bus_name,
        licensePlate: row.license_plate,
      },
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// PUBLIC - Get stops for a schedule's line
// ============================================
app.get("/schedules/:scheduleId/stops", async (req, res) => {
  try {
    const { scheduleId } = req.params;

    if (DEV_MOCK) {
      const schedule = (_mock.schedules || []).find(
        (s) => Number(s.id) === Number(scheduleId),
      );
      if (!schedule) {
        return res.status(404).json({ error: "schedule_not_found" });
      }
      const routeStops = (_mock.routeStops || [])
        .filter((rs) => Number(rs.busLineId) === Number(schedule.busLineId))
        .sort((a, b) => a.stopOrder - b.stopOrder);

      // Map to match database response format
      const formattedStops = routeStops.map((rs) => {
        const stop = (_mock.stops || []).find(
          (s) => Number(s.id) === Number(rs.stopId),
        );
        return {
          id: rs.id,
          order: rs.stopOrder,
          name: stop?.name || rs.name || "Unknown Stop",
          latitude: stop?.latitude ?? rs.latitude ?? 0,
          longitude: stop?.longitude ?? rs.longitude ?? 0,
          estimatedArrivalMinutes: rs.estimatedArrivalMinutes || 0,
        };
      });
      return res.json({ stops: formattedStops });
    }

    const scheduleResult = await db.query(
      `SELECT bus_line_id FROM transit.schedules WHERE id = $1`,
      [scheduleId],
    );

    if (scheduleResult.rows.length === 0) {
      return res.status(404).json({ error: "schedule_not_found" });
    }

    const busLineId = scheduleResult.rows[0].bus_line_id;

    const stopsResult = await db.query(
      `
      SELECT 
        rs.id,
        rs.stop_order,
        s.name,
        s.latitude,
        s.longitude,
        rs.estimated_arrival_minutes
      FROM transit.route_stops rs
      JOIN transit.stops s ON s.id = rs.stop_id
      WHERE rs.bus_line_id = $1
      ORDER BY rs.stop_order ASC
    `,
      [busLineId],
    );

    res.json({
      stops: stopsResult.rows.map((row) => ({
        id: row.id,
        order: row.stop_order,
        name: row.name,
        latitude: parseFloat(row.latitude),
        longitude: parseFloat(row.longitude),
        estimatedArrivalMinutes: row.estimated_arrival_minutes,
      })),
    });
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// DRIVER - Mark stop as passed (updates realtime state)
// ============================================
app.post(
  "/driver/schedules/:scheduleId/stops/:stopOrder/passed",
  authMiddleware,
  async (req, res) => {
    try {
      const scheduleId = Number(req.params.scheduleId);
      const stopOrder = Number(req.params.stopOrder);

      if (
        !Number.isFinite(scheduleId) ||
        !Number.isFinite(stopOrder) ||
        stopOrder < 1
      ) {
        return res
          .status(400)
          .json({ error: "invalid_schedule_or_stop_order" });
      }

      const actualPassedAt = req.body?.actualPassedAt
        ? new Date(req.body.actualPassedAt)
        : new Date();
      if (Number.isNaN(actualPassedAt.getTime())) {
        return res.status(400).json({ error: "invalid_actual_passed_at" });
      }

      if (DEV_MOCK) {
        const schedule = (_mock.schedules || []).find(
          (s) => Number(s.id) === scheduleId,
        );
        if (!schedule) {
          return res.status(404).json({ error: "schedule_not_found" });
        }

        const routeStop = (_mock.routeStops || []).find(
          (rs) =>
            Number(rs.busLineId) === Number(schedule.busLineId) &&
            Number(rs.stopOrder) === stopOrder,
        );

        if (!routeStop) {
          return res.status(404).json({ error: "stop_not_found_for_schedule" });
        }

        const stop = (_mock.stops || []).find(
          (s) => Number(s.id) === Number(routeStop.stopId),
        );
        // Allow caller to specify which occurrence date this pertains to (for recurring templates)
        const occurrenceDateKey =
          req.query.date || req.body.date || toDateKey(schedule.startTime);
        const templateStart = new Date(schedule.startTime);
        const scheduledPassedAt = new Date(`${occurrenceDateKey}T00:00:00`);
        scheduledPassedAt.setHours(
          templateStart.getHours(),
          templateStart.getMinutes(),
          templateStart.getSeconds(),
          templateStart.getMilliseconds(),
        );
        scheduledPassedAt.setMinutes(
          scheduledPassedAt.getMinutes() +
            (Number(routeStop.estimatedArrivalMinutes) || 0),
        );

        const existingIndex = (_mock.scheduleStopProgress || []).findIndex(
          (p) =>
            Number(p.scheduleId) === scheduleId &&
            Number(p.stopOrder) === stopOrder,
        );

        const progressRow = {
          id:
            existingIndex >= 0
              ? _mock.scheduleStopProgress[existingIndex].id
              : _mock.nextScheduleStopProgressId++,
          scheduleId,
          busLineId: Number(schedule.busLineId),
          stopId: Number(routeStop.stopId),
          stopOrder,
          stopName: stop?.name || routeStop.name || "Unknown Stop",
          estimatedArrivalMinutes:
            Number(routeStop.estimatedArrivalMinutes) || 0,
          scheduledPassedAt: scheduledPassedAt.toISOString(),
          scheduledPassedDate: occurrenceDateKey,
          actualPassedAt: actualPassedAt.toISOString(),
          delayMinutes,
          markedByUserId: Number(req.user?.userId) || null,
          createdAt: new Date().toISOString(),
        };

        if (existingIndex >= 0) {
          _mock.scheduleStopProgress[existingIndex] = progressRow;
        } else {
          _mock.scheduleStopProgress.push(progressRow);
        }

        const totalStops = (_mock.routeStops || []).filter(
          (rs) => Number(rs.busLineId) === Number(schedule.busLineId),
        ).length;
        const passedCount = (_mock.scheduleStopProgress || []).filter(
          (p) =>
            Number(p.scheduleId) === scheduleId &&
            p.scheduledPassedDate === occurrenceDateKey,
        ).length;

        if (passedCount >= totalStops) {
          schedule.status = "completed";
          schedule.endTime = actualPassedAt.toISOString();
        } else if (schedule.status === "planned") {
          schedule.status = "in_progress";
        }

        return res.json({
          scheduleId,
          stopOrder,
          status: schedule.status,
          delayMinutes,
          passedStops: passedCount,
          totalStops,
          occurrenceDate: occurrenceDateKey,
        });
      }

      await ensureScheduleStopProgressTable();

      const scheduleResult = await db.query(
        `
      SELECT s.id, s.bus_line_id, s.start_time, s.status
      FROM transit.schedules s
      WHERE s.id = $1
    `,
        [scheduleId],
      );

      if (scheduleResult.rows.length === 0) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      const schedule = scheduleResult.rows[0];

      const routeStopResult = await db.query(
        `
      SELECT
        rs.stop_id,
        rs.stop_order,
        rs.estimated_arrival_minutes,
        s.name AS stop_name
      FROM transit.route_stops rs
      JOIN transit.stops s ON s.id = rs.stop_id
      WHERE rs.bus_line_id = $1
        AND rs.stop_order = $2
      LIMIT 1
    `,
        [schedule.bus_line_id, stopOrder],
      );

      if (routeStopResult.rows.length === 0) {
        return res.status(404).json({ error: "stop_not_found_for_schedule" });
      }

      const routeStop = routeStopResult.rows[0];
      // Determine occurrence date (for recurring templates callers can pass ?date=YYYY-MM-DD or body.date)
      let occurrenceDateKey =
        req.query.date || req.body.date || toDateKey(schedule.start_time);

      // If this schedule is a recurring template, map to or create a concrete instance for the occurrence date
      const weekdays = parseWeekdaysValue(schedule.weekdays);
      let instanceScheduleId = scheduleId;
      if (weekdays && weekdays.length > 0) {
        // If no date provided but template occurs today, use today
        if (!occurrenceDateKey) {
          const todayKey = new Date().toISOString().slice(0, 10);
          if (scheduleOccursOnDate(schedule, todayKey))
            occurrenceDateKey = todayKey;
        }

        if (occurrenceDateKey) {
          const existingInstance = await db.query(
            `SELECT id FROM transit.schedules WHERE template_id = $1 AND DATE(start_time) = $2 LIMIT 1`,
            [scheduleId, occurrenceDateKey],
          );

          if (existingInstance.rows.length > 0) {
            instanceScheduleId = existingInstance.rows[0].id;
          } else {
            // Create instance from template
            const templateStart = new Date(schedule.start_time);
            const templateEnd = schedule.end_time
              ? new Date(schedule.end_time)
              : null;
            const occurrenceStart = new Date(`${occurrenceDateKey}T00:00:00`);
            occurrenceStart.setHours(
              templateStart.getHours(),
              templateStart.getMinutes(),
              templateStart.getSeconds(),
              templateStart.getMilliseconds(),
            );

            let occurrenceEnd = null;
            if (
              templateEnd &&
              Number.isFinite(templateEnd.getTime()) &&
              Number.isFinite(templateStart.getTime())
            ) {
              const duration = templateEnd.getTime() - templateStart.getTime();
              occurrenceEnd = new Date(occurrenceStart.getTime() + duration);
            }

            const hasTemplateIdCol = await db.query(`
            SELECT 1 FROM information_schema.columns
            WHERE table_schema='transit' AND table_name='schedules' AND column_name='template_id'
          `);

            let insertRes;
            if (hasTemplateIdCol.rows.length > 0) {
              insertRes = await db.query(
                `
              WITH next_id AS (SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules)
              INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status, template_id)
              SELECT next_id.id, $1, $2, $3, $4, $5, 'planned', $6
              FROM next_id
              RETURNING id
            `,
                [
                  schedule.bus_line_id,
                  schedule.bus_id,
                  schedule.driver_id,
                  occurrenceStart.toISOString(),
                  occurrenceEnd ? occurrenceEnd.toISOString() : null,
                  scheduleId,
                ],
              );
            } else {
              insertRes = await db.query(
                `
              WITH next_id AS (SELECT COALESCE(MAX(id), 0) + 1 AS id FROM transit.schedules)
              INSERT INTO transit.schedules (id, bus_line_id, bus_id, driver_id, start_time, end_time, status)
              SELECT next_id.id, $1, $2, $3, $4, $5, 'planned'
              FROM next_id
              RETURNING id
            `,
                [
                  schedule.bus_line_id,
                  schedule.bus_id,
                  schedule.driver_id,
                  occurrenceStart.toISOString(),
                  occurrenceEnd ? occurrenceEnd.toISOString() : null,
                ],
              );
            }

            instanceScheduleId = insertRes.rows[0].id;
          }
        }
      }

      const templateStart = new Date(schedule.start_time);
      const scheduledPassedAt = new Date(`${occurrenceDateKey}T00:00:00`);
      scheduledPassedAt.setHours(
        templateStart.getHours(),
        templateStart.getMinutes(),
        templateStart.getSeconds(),
        templateStart.getMilliseconds(),
      );
      scheduledPassedAt.setMinutes(
        scheduledPassedAt.getMinutes() +
          (Number(routeStop.estimated_arrival_minutes) || 0),
      );

      await db.query(
        `
      INSERT INTO transit.schedule_stop_progress (
        schedule_id,
        bus_line_id,
        stop_id,
        stop_order,
        stop_name,
        estimated_arrival_minutes,
        scheduled_passed_at,
        scheduled_passed_date,
        actual_passed_at,
        marked_by_user_id
      )
      VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10)
      ON CONFLICT (schedule_id, stop_order, scheduled_passed_date)
      DO UPDATE SET
        actual_passed_at = EXCLUDED.actual_passed_at,
        marked_by_user_id = EXCLUDED.marked_by_user_id,
        created_at = NOW()
    `,
        [
          instanceScheduleId,
          Number(schedule.bus_line_id),
          Number(routeStop.stop_id),
          stopOrder,
          routeStop.stop_name,
          Number(routeStop.estimated_arrival_minutes) || 0,
          scheduledPassedAt.toISOString(),
          occurrenceDateKey,
          actualPassedAt.toISOString(),
          Number(req.user?.userId) || null,
        ],
      );

      const totalsResult = await db.query(
        `
      SELECT
        (SELECT COUNT(*)::int FROM transit.route_stops WHERE bus_line_id = $1) AS total_stops,
        (SELECT COUNT(*)::int FROM transit.schedule_stop_progress WHERE schedule_id = $2 AND scheduled_passed_date = $3) AS passed_stops
    `,
        [schedule.bus_line_id, instanceScheduleId, occurrenceDateKey],
      );

      const totalStops = Number(totalsResult.rows[0]?.total_stops || 0);
      const passedStops = Number(totalsResult.rows[0]?.passed_stops || 0);
      const isCompleted = totalStops > 0 && passedStops >= totalStops;
      const nextStatus = isCompleted ? "completed" : "in_progress";

      await db.query(
        `
      UPDATE transit.schedules
      SET
        status = $2,
        end_time = CASE WHEN $2 = 'completed' THEN $3 ELSE end_time END
      WHERE id = $1
    `,
        [instanceScheduleId, nextStatus, actualPassedAt.toISOString()],
      );

      // Calculate delay live
      const delayMinutes = Math.round(
        (actualPassedAt.getTime() - scheduledPassedAt.getTime()) / 60000,
      );

      res.json({
        scheduleId,
        stopOrder,
        status: nextStatus,
        delayMinutes,
        passedStops,
        totalStops,
      });
    } catch (err) {
      console.error(
        "POST /driver/schedules/:scheduleId/stops/:stopOrder/passed error:",
        err,
      );
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// PUBLIC - Live progress for passengers
// ============================================
app.get("/public/schedules/:scheduleId/progress", async (req, res) => {
  try {
    const scheduleId = Number(req.params.scheduleId);
    if (!Number.isFinite(scheduleId)) {
      return res.status(400).json({ error: "invalid_schedule_id" });
    }

    if (DEV_MOCK) {
      const schedule = (_mock.schedules || []).find(
        (s) => Number(s.id) === scheduleId,
      );
      if (!schedule) {
        return res.status(404).json({ error: "schedule_not_found" });
      }

      const busLine = (_mock.busLines || []).find(
        (bl) => Number(bl.id) === Number(schedule.busLineId),
      );
      const routeStops = (_mock.routeStops || [])
        .filter((rs) => Number(rs.busLineId) === Number(schedule.busLineId))
        .sort((a, b) => Number(a.stopOrder) - Number(b.stopOrder));

      const mockProgressDate =
        req.query.date || req.query.occurrenceDate || null;
      let progressEvents = (_mock.scheduleStopProgress || []).filter(
        (p) => Number(p.scheduleId) === scheduleId,
      );
      if (mockProgressDate) {
        progressEvents = progressEvents.filter(
          (p) => p.scheduledPassedDate === mockProgressDate,
        );
      }
      progressEvents = progressEvents.sort(
        (a, b) => Number(a.stopOrder) - Number(b.stopOrder),
      );

      const progressByOrder = new Map(
        progressEvents.map((p) => [Number(p.stopOrder), p]),
      );
      const latestProgress =
        progressEvents.length > 0
          ? progressEvents[progressEvents.length - 1]
          : null;
      const currentDelayMinutes = latestProgress
        ? Number(latestProgress.delayMinutes) || 0
        : 0;

      const occurrenceDateKey =
        req.query.date ||
        req.query.occurrenceDate ||
        toDateKey(schedule.startTime);
      const stops = routeStops.map((rs) => {
        const stop = (_mock.stops || []).find(
          (s) => Number(s.id) === Number(rs.stopId),
        );
        const templateStart = new Date(schedule.startTime);
        const scheduledTime = new Date(`${occurrenceDateKey}T00:00:00`);
        scheduledTime.setHours(
          templateStart.getHours(),
          templateStart.getMinutes(),
          templateStart.getSeconds(),
          templateStart.getMilliseconds(),
        );
        scheduledTime.setMinutes(
          scheduledTime.getMinutes() +
            (Number(rs.estimatedArrivalMinutes) || 0),
        );
        const progress = progressByOrder.get(Number(rs.stopOrder));

        return {
          stopId: Number(rs.stopId),
          stopOrder: Number(rs.stopOrder),
          stopName: stop?.name || rs.name || "Unknown Stop",
          estimatedArrivalMinutes: Number(rs.estimatedArrivalMinutes) || 0,
          scheduledPassedAt: scheduledTime.toISOString(),
          actualPassedAt: progress?.actualPassedAt || null,
          delayMinutes: progress ? Number(progress.delayMinutes) || 0 : null,
          status: progress ? "passed" : "pending",
        };
      });

      const passedStops = stops.filter((s) => s.status === "passed");
      const nextStop = stops.find((s) => s.status === "pending") || null;
      const driverState =
        passedStops.length === 0
          ? "not_started"
          : passedStops.length >= stops.length
            ? "completed"
            : "en_route";

      return res.json({
        schedule: {
          id: scheduleId,
          lineNumber: Number(busLine?.lineNumber || 0),
          startStop: busLine?.startStop || null,
          endStop: busLine?.endStop || null,
          startTime: schedule.startTime,
          endTime: schedule.endTime,
          status: schedule.status,
        },
        driverState,
        currentDelayMinutes,
        passedStopCount: passedStops.length,
        totalStopCount: stops.length,
        nextStop: nextStop
          ? {
              ...nextStop,
              predictedPassedAt: new Date(
                new Date(nextStop.scheduledPassedAt).getTime() +
                  currentDelayMinutes * 60000,
              ).toISOString(),
            }
          : null,
        stops,
        updatedAt: latestProgress?.actualPassedAt || null,
      });
    }

    await ensureScheduleStopProgressTable();

    const scheduleResult = await db.query(
      `
      SELECT
        s.id,
        s.bus_line_id,
        s.start_time,
        s.end_time,
        s.status,
        bl.line_number,
        bl.start_stop,
        bl.end_stop
      FROM transit.schedules s
      JOIN transit.bus_lines bl ON bl.id = s.bus_line_id
      WHERE s.id = $1
      LIMIT 1
    `,
      [scheduleId],
    );

    if (scheduleResult.rows.length === 0) {
      return res.status(404).json({ error: "schedule_not_found" });
    }

    const schedule = scheduleResult.rows[0];

    const routeStopsResult = await db.query(
      `
      SELECT
        rs.stop_id,
        rs.stop_order,
        rs.estimated_arrival_minutes,
        s.name AS stop_name
      FROM transit.route_stops rs
      JOIN transit.stops s ON s.id = rs.stop_id
      WHERE rs.bus_line_id = $1
      ORDER BY rs.stop_order ASC
    `,
      [schedule.bus_line_id],
    );

    // Allow querying progress for a specific occurrence date (recurring templates)
    const progressDate = req.query.date || req.query.occurrenceDate || null;
    let progressResult;
    if (progressDate) {
      progressResult = await db.query(
        `
        SELECT
          stop_order,
          actual_passed_at,
          scheduled_passed_at,
          scheduled_passed_date
        FROM transit.schedule_stop_progress
        WHERE schedule_id = $1 AND scheduled_passed_date = $2
        ORDER BY stop_order ASC
      `,
        [scheduleId, progressDate],
      );
    } else {
      progressResult = await db.query(
        `
        SELECT
          stop_order,
          actual_passed_at,
          scheduled_passed_at,
          scheduled_passed_date
        FROM transit.schedule_stop_progress
        WHERE schedule_id = $1
        ORDER BY scheduled_passed_at ASC, stop_order ASC
      `,
        [scheduleId],
      );
    }

    const progressByOrder = new Map(
      progressResult.rows.map((row) => [Number(row.stop_order), row]),
    );
    const latestProgress =
      progressResult.rows.length > 0
        ? progressResult.rows[progressResult.rows.length - 1]
        : null;

    // Calculate delay live from latest passed stop
    let currentDelayMinutes = null;
    if (
      latestProgress &&
      latestProgress.actual_passed_at &&
      latestProgress.scheduled_passed_at
    ) {
      const actualTime = new Date(latestProgress.actual_passed_at);
      const scheduledTime = new Date(latestProgress.scheduled_passed_at);
      currentDelayMinutes = Math.round(
        (actualTime.getTime() - scheduledTime.getTime()) / 60000,
      );
    }

    const occurrenceDateKeyForMapping =
      progressDate || toDateKey(schedule.start_time);

    const stops = routeStopsResult.rows.map((row) => {
      const etaMinutes = Number(row.estimated_arrival_minutes) || 0;
      const templateStart = new Date(schedule.start_time);
      const scheduledPassedAt = new Date(
        `${occurrenceDateKeyForMapping}T00:00:00`,
      );
      scheduledPassedAt.setHours(
        templateStart.getHours(),
        templateStart.getMinutes(),
        templateStart.getSeconds(),
        templateStart.getMilliseconds(),
      );
      scheduledPassedAt.setMinutes(scheduledPassedAt.getMinutes() + etaMinutes);

      const progress = progressByOrder.get(Number(row.stop_order));

      return {
        stopId: Number(row.stop_id),
        stopOrder: Number(row.stop_order),
        stopName: row.stop_name,
        estimatedArrivalMinutes: etaMinutes,
        scheduledPassedAt: scheduledPassedAt.toISOString(),
        actualPassedAt: progress?.actual_passed_at || null,
        delayMinutes: (() => {
          if (progress?.actual_passed_at && progress?.scheduled_passed_at) {
            const actualTime = new Date(progress.actual_passed_at);
            const scheduledTime = new Date(progress.scheduled_passed_at);
            return Math.round(
              (actualTime.getTime() - scheduledTime.getTime()) / 60000,
            );
          }
          return null;
        })(),
        status: progress ? "passed" : "pending",
      };
    });

    const passedStops = stops.filter((s) => s.status === "passed");
    const nextStop = stops.find((s) => s.status === "pending") || null;

    const driverState =
      passedStops.length === 0
        ? "not_started"
        : passedStops.length >= stops.length
          ? "completed"
          : "en_route";

    res.json({
      schedule: {
        id: Number(schedule.id),
        lineNumber: Number(schedule.line_number),
        startStop: schedule.start_stop,
        endStop: schedule.end_stop,
        startTime: schedule.start_time,
        endTime: schedule.end_time,
        status: schedule.status,
      },
      driverState,
      currentDelayMinutes,
      passedStopCount: passedStops.length,
      totalStopCount: stops.length,
      nextStop: nextStop
        ? {
            ...nextStop,
            predictedPassedAt: new Date(
              new Date(nextStop.scheduledPassedAt).getTime() +
                currentDelayMinutes * 60000,
            ).toISOString(),
          }
        : null,
      stops,
      updatedAt: latestProgress?.actual_passed_at || null,
    });
  } catch (err) {
    console.error("GET /public/schedules/:scheduleId/progress error:", err);
    res.status(500).json({ error: "internal_error", details: err.message });
  }
});

// ============================================
// ADMIN - Check driver conflicts for generated schedules
// ============================================
app.post(
  "/admin/check-driver-conflicts",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const {
        generatedTimes,
        drivers,
        busLineId,
        busId,
        weekdays = [],
      } = req.body;

      if (!Array.isArray(generatedTimes) || !Array.isArray(drivers)) {
        return res.status(400).json({ error: "missing_required_fields" });
      }

      // Get all existing schedules
      const schedResult = DEV_MOCK
        ? { rows: _mock.schedules || [] }
        : await db.query(
            `SELECT * FROM transit.schedules WHERE status IN ('planned', 'active')`,
          );

      const existingSchedules = schedResult.rows.map((row) => ({
        ...row,
        weekdays: parseWeekdaysValue(row.weekdays || row.weekday_list || "[]"),
      }));

      // For each generated time, check conflicts with each driver
      const assignments = generatedTimes.map((timeStr) => {
        const driverAssignments = drivers.map((driver) => {
          const hasConflict = checkDriverConflict(
            driver.id,
            timeStr,
            timeStr, // Will be checked with start/end times of conflicts
            weekdays,
            existingSchedules,
          );

          return {
            driverId: driver.id,
            driverName: driver.name,
            hasConflict,
            assigned: false,
          };
        });

        return {
          time: timeStr,
          driverAssignments,
          assignedDriverId: null,
        };
      });

      res.json({ assignments });
    } catch (err) {
      console.error("/admin/check-driver-conflicts error:", err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

// ============================================
// ADMIN - Auto-assign schedules to drivers
// ============================================
app.post(
  "/admin/assign-schedules",
  authMiddleware,
  adminMiddleware,
  async (req, res) => {
    try {
      const { assignments, busLineId, busId, weekdays = [] } = req.body;

      if (!Array.isArray(assignments)) {
        return res.status(400).json({ error: "missing_assignments" });
      }

      // Group assignments by driver (round-robin or custom)
      const schedulesToCreate = [];
      let driverIndex = 0;

      for (const assignment of assignments) {
        if (!assignment.time || !assignment.assignedDriverId) continue;

        const startTime = assignment.time;
        const endTime = assignment.endTime;

        schedulesToCreate.push({
          busLineId,
          busId,
          driverId: assignment.assignedDriverId,
          startTime,
          endTime,
          weekdays,
        });
      }

      // Use bulk create endpoint logic
      if (DEV_MOCK) {
        if (!_mock.schedules) _mock.schedules = [];
        const createdSchedules = [];

        for (const entry of schedulesToCreate) {
          const schedule = {
            id: _mock.nextScheduleId || 1,
            ...entry,
            status: "planned",
            createdAt: new Date().toISOString(),
          };
          _mock.nextScheduleId = (_mock.nextScheduleId || 1) + 1;
          _mock.schedules.push(schedule);
          createdSchedules.push(schedule);
        }

        return res.status(201).json({
          createdCount: createdSchedules.length,
          schedules: createdSchedules,
        });
      }

      // For DB: use bulk insert
      res.status(201).json({
        createdCount: schedulesToCreate.length,
        message: "would_insert_schedules",
      });
    } catch (err) {
      console.error("/admin/assign-schedules error:", err);
      res.status(500).json({ error: "internal_error", details: err.message });
    }
  },
);

const PORT = process.env.PORT || 5001;

// Initialize database tables on startup
(async () => {
  try {
    await ensureScheduleStopProgressTable();
    console.log("✓ Database tables initialized");
  } catch (err) {
    console.error("⚠ Error initializing tables:", err.message);
  }

  app.listen(PORT, () => console.log(`Transit API listening on ${PORT}`));
})();

module.exports = app;