import { Hono } from 'hono';
import type { RowDataPacket } from 'mysql2';
import pool from '../db.js';
import type { AuthUser } from '../auth/types.js';
import { canAccessEnergy } from '../auth/types.js';

type HydrogenHeatmapMetric = 'kg' | 'refuels' | 'vehicles';
type Payer = 'all' | 'lingniu' | 'customer';

type StationRow = RowDataPacket & {
  station_id: string;
  station_name: string;
  address: string;
  longitude: string | number;
  latitude: string | number;
  kg: string | number;
  refuel_count: string | number;
  vehicle_count: string | number;
  first_refuel: string;
  last_refuel: string;
};

const DEFAULT_START = '2026-01-01';
const DEFAULT_END = '2026-07-13';
const VALID_COORDINATE = `
  o.longitude BETWEEN 73.5 AND 135.1
  AND o.latitude BETWEEN 18 AND 53.6
  AND COALESCE(o.province, '') NOT LIKE '%西藏%'
`;

function isDate(value: string | undefined): value is string {
  return Boolean(value && /^\d{4}-\d{2}-\d{2}$/.test(value));
}

function parseMetric(value: string | undefined): HydrogenHeatmapMetric {
  if (value === 'refuels' || value === 'vehicles') return value;
  return 'kg';
}

function parsePayer(value: string | undefined): Payer {
  if (value === 'lingniu' || value === 'customer') return value;
  return 'all';
}

function buildWhere(startDate: string, endDate: string, query: string, payer: Payer) {
  const clauses = [
    `b.del_flag = '0'`,
    `DATE(b.refuel_time) BETWEEN ? AND ?`,
    VALID_COORDINATE,
  ];
  const params: Array<string | number> = [startDate, endDate];

  if (query) {
    clauses.push(`CONVERT(CONCAT_WS(' ', s.station_name, s.station_short_name, b.station_name, o.station_name, o.fixed_station_name, o.station_address, o.city) USING utf8mb4) COLLATE utf8mb4_unicode_ci LIKE CONVERT(? USING utf8mb4) COLLATE utf8mb4_unicode_ci`);
    params.push(`%${query}%`);
  }
  if (payer === 'lingniu') {
    clauses.push(`COALESCE(b.customer_price, 0) <= 0 AND COALESCE(b.fee_total, 0) <= 0`);
  } else if (payer === 'customer') {
    clauses.push(`(COALESCE(b.customer_price, 0) > 0 OR COALESCE(b.fee_total, 0) > 0)`);
  }
  return { sql: clauses.join(' AND '), params };
}

async function loadStations(startDate: string, endDate: string, query: string, payer: Payer): Promise<StationRow[]> {
  const where = buildWhere(startDate, endDate, query, payer);
  const [rows] = await pool.execute<StationRow[]>(`
    SELECT
      CAST(b.station_id AS CHAR) AS station_id,
      COALESCE(
        NULLIF(MAX(s.station_short_name), ''),
        NULLIF(MAX(s.station_name), ''),
        NULLIF(MAX(b.station_name), ''),
        NULLIF(MAX(o.fixed_station_name), ''),
        CONCAT('未知站点 #', b.station_id)
      ) AS station_name,
      COALESCE(NULLIF(MAX(o.station_address), ''), NULLIF(MAX(s.station_address), ''), '') AS address,
      MAX(o.longitude) AS longitude,
      MAX(o.latitude) AS latitude,
      ROUND(SUM(COALESCE(b.amount_kg, 0)), 2) AS kg,
      COUNT(*) AS refuel_count,
      COUNT(DISTINCT COALESCE(NULLIF(TRIM(b.license_plate), ''), CONCAT('vehicle#', b.vehicle_id))) AS vehicle_count,
      DATE_FORMAT(MIN(b.refuel_time), '%Y-%m-%d %H:%i:%s') AS first_refuel,
      DATE_FORMAT(MAX(b.refuel_time), '%Y-%m-%d %H:%i:%s') AS last_refuel
    FROM hydrogen_fuel_ledger b
    LEFT JOIN hydrogen_station s ON s.id = b.station_id AND s.del_flag = '0'
    INNER JOIN tab_outside_hydrogen_site o ON o.inner_site_id = b.station_id
    WHERE ${where.sql}
    GROUP BY b.station_id
  `, where.params);
  return rows;
}

function metricValue(row: StationRow, metric: HydrogenHeatmapMetric): number {
  if (metric === 'refuels') return Number(row.refuel_count) || 0;
  if (metric === 'vehicles') return Number(row.vehicle_count) || 0;
  return Number(row.kg) || 0;
}

function serializeStation(row: StationRow, metric: HydrogenHeatmapMetric) {
  return {
    stationId: row.station_id,
    stationName: row.station_name,
    address: row.address,
    lng: Number(row.longitude),
    lat: Number(row.latitude),
    kg: Number(row.kg) || 0,
    refuelCount: Number(row.refuel_count) || 0,
    vehicleCount: Number(row.vehicle_count) || 0,
    firstRefuel: row.first_refuel,
    lastRefuel: row.last_refuel,
    metricValue: metricValue(row, metric),
  };
}

function haversineKm(leftLng: number, leftLat: number, rightLng: number, rightLat: number): number {
  const radians = (degrees: number) => degrees * Math.PI / 180;
  const earthRadius = 6371;
  const dLat = radians(rightLat - leftLat);
  const dLng = radians(rightLng - leftLng);
  const a = Math.sin(dLat / 2) ** 2
    + Math.cos(radians(leftLat)) * Math.cos(radians(rightLat)) * Math.sin(dLng / 2) ** 2;
  return earthRadius * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
}

const router = new Hono();

router.use('*', async (c, next) => {
  const user = (c as { get: (key: string) => unknown }).get('user') as AuthUser | undefined;
  if (user && !canAccessEnergy(user.roles)) {
    return c.json({ error: 'Forbidden: 能源管理访问需要 BI-LEADER-ENERGY 角色' }, 403);
  }
  return next();
});

router.get('/config', (c) => {
  const key = process.env.AMAP_WEB_KEY;
  const securityCode = process.env.AMAP_SECURITY_JS_CODE;
  if (!key || !securityCode) return c.json({ error: '高德地图配置缺失' }, 503);
  return c.json({ key, securityCode });
});

router.get('/meta', async (c) => {
  const [profileRows, optionRows] = await Promise.all([
    pool.query<RowDataPacket[]>(`
      SELECT
        DATE_FORMAT(MIN(b.refuel_time), '%Y-%m-%d') AS start_date,
        DATE_FORMAT(MAX(b.refuel_time), '%Y-%m-%d') AS end_date,
        COUNT(*) AS total_refuel_count,
        ROUND(SUM(COALESCE(b.amount_kg, 0)), 2) AS total_kg,
        COUNT(DISTINCT b.station_id) AS total_station_count,
        COUNT(DISTINCT COALESCE(NULLIF(TRIM(b.license_plate), ''), CONCAT('vehicle#', b.vehicle_id))) AS vehicle_count,
        SUM(CASE WHEN ${VALID_COORDINATE} THEN 1 ELSE 0 END) AS eligible_refuel_count,
        ROUND(SUM(CASE WHEN ${VALID_COORDINATE} THEN COALESCE(b.amount_kg, 0) ELSE 0 END), 2) AS eligible_kg,
        COUNT(DISTINCT CASE WHEN ${VALID_COORDINATE} THEN b.station_id END) AS eligible_station_count
      FROM hydrogen_fuel_ledger b
      LEFT JOIN tab_outside_hydrogen_site o ON o.inner_site_id = b.station_id
      WHERE b.del_flag = '0'
    `),
    pool.query<RowDataPacket[]>(`
      SELECT
        CAST(s.id AS CHAR) AS station_id,
        COALESCE(NULLIF(s.station_short_name, ''), s.station_name) AS station_name
      FROM hydrogen_station s
      INNER JOIN tab_outside_hydrogen_site o ON o.inner_site_id = s.id
      INNER JOIN hydrogen_fuel_ledger b ON b.station_id = s.id AND b.del_flag = '0'
      WHERE s.del_flag = '0' AND ${VALID_COORDINATE}
      GROUP BY s.id, s.station_short_name, s.station_name
      ORDER BY station_name
    `),
  ]);
  const profile = profileRows[0][0] || {};
  const totalRefuelCount = Number(profile.total_refuel_count) || 0;
  const eligibleRefuelCount = Number(profile.eligible_refuel_count) || 0;
  return c.json({
    startDate: profile.start_date || DEFAULT_START,
    endDate: profile.end_date || DEFAULT_END,
    totalRefuelCount,
    eligibleRefuelCount,
    excludedRefuelCount: Math.max(0, totalRefuelCount - eligibleRefuelCount),
    gpsCoverageRate: totalRefuelCount ? eligibleRefuelCount / totalRefuelCount : 0,
    totalKg: Number(profile.total_kg) || 0,
    eligibleKg: Number(profile.eligible_kg) || 0,
    vehicleCount: Number(profile.vehicle_count) || 0,
    totalStationCount: Number(profile.total_station_count) || 0,
    eligibleStationCount: Number(profile.eligible_station_count) || 0,
    stations: optionRows[0].map((row) => ({
      stationId: String(row.station_id),
      stationName: String(row.station_name),
    })),
  });
});

router.get('/points', async (c) => {
  const startDate = isDate(c.req.query('startDate')) ? c.req.query('startDate')! : DEFAULT_START;
  const endDate = isDate(c.req.query('endDate')) ? c.req.query('endDate')! : DEFAULT_END;
  if (startDate > endDate) return c.json({ error: '开始日期不能晚于结束日期' }, 400);
  const query = (c.req.query('query') || '').trim();
  const payer = parsePayer(c.req.query('payer'));
  const metric = parseMetric(c.req.query('metric'));
  const stations = await loadStations(startDate, endDate, query, payer);
  const ranked = [...stations].sort((left, right) => metricValue(right, metric) - metricValue(left, metric));
  const points = ranked.map((row) => ({
    lng: Number(row.longitude),
    lat: Number(row.latitude),
    count: metricValue(row, metric),
  }));
  const where = buildWhere(startDate, endDate, query, payer);
  const [summaryRows] = await pool.execute<RowDataPacket[]>(`
    SELECT
      ROUND(SUM(COALESCE(b.amount_kg, 0)), 2) AS kg,
      COUNT(*) AS refuel_count,
      COUNT(DISTINCT COALESCE(NULLIF(TRIM(b.license_plate), ''), CONCAT('vehicle#', b.vehicle_id))) AS vehicle_count,
      COUNT(DISTINCT b.station_id) AS station_count,
      COUNT(DISTINCT DATE(b.refuel_time)) AS day_count
    FROM hydrogen_fuel_ledger b
    LEFT JOIN hydrogen_station s ON s.id = b.station_id AND s.del_flag = '0'
    INNER JOIN tab_outside_hydrogen_site o ON o.inner_site_id = b.station_id
    WHERE ${where.sql}
  `, where.params);
  const summary = summaryRows[0] || {};
  return c.json({
    startDate,
    endDate,
    metric,
    payer,
    kg: Number(summary.kg) || 0,
    refuelCount: Number(summary.refuel_count) || 0,
    vehicleCount: Number(summary.vehicle_count) || 0,
    stationCount: Number(summary.station_count) || 0,
    dayCount: Number(summary.day_count) || 0,
    points,
    max: Math.max(1, ...points.map((point) => point.count)),
    topStations: ranked.slice(0, 10).map((row) => serializeStation(row, metric)),
  });
});

router.get('/nearby', async (c) => {
  const longitude = Number(c.req.query('lng'));
  const latitude = Number(c.req.query('lat'));
  if (!Number.isFinite(longitude) || !Number.isFinite(latitude)) return c.json({ error: '经纬度参数无效' }, 400);
  const startDate = isDate(c.req.query('startDate')) ? c.req.query('startDate')! : DEFAULT_START;
  const endDate = isDate(c.req.query('endDate')) ? c.req.query('endDate')! : DEFAULT_END;
  const query = (c.req.query('query') || '').trim();
  const payer = parsePayer(c.req.query('payer'));
  const metric = parseMetric(c.req.query('metric'));
  const radiusKm = Math.min(200, Math.max(5, Number(c.req.query('radiusKm')) || 50));
  const stations = await loadStations(startDate, endDate, query, payer);
  const nearby = stations.filter((row) => haversineKm(
    longitude,
    latitude,
    Number(row.longitude),
    Number(row.latitude),
  ) <= radiusKm);
  const nearbyIds = nearby.map((row) => row.station_id);
  let nearbySummary = { kg: 0, refuelCount: 0, vehicleCount: 0, stationCount: 0 };
  if (nearbyIds.length) {
    const placeholders = nearbyIds.map(() => '?').join(',');
    const where = buildWhere(startDate, endDate, query, payer);
    const [rows] = await pool.execute<RowDataPacket[]>(`
      SELECT
        ROUND(SUM(COALESCE(b.amount_kg, 0)), 2) AS kg,
        COUNT(*) AS refuel_count,
        COUNT(DISTINCT COALESCE(NULLIF(TRIM(b.license_plate), ''), CONCAT('vehicle#', b.vehicle_id))) AS vehicle_count,
        COUNT(DISTINCT b.station_id) AS station_count
      FROM hydrogen_fuel_ledger b
      LEFT JOIN hydrogen_station s ON s.id = b.station_id AND s.del_flag = '0'
      INNER JOIN tab_outside_hydrogen_site o ON o.inner_site_id = b.station_id
      WHERE ${where.sql} AND CAST(b.station_id AS CHAR) IN (${placeholders})
    `, [...where.params, ...nearbyIds]);
    nearbySummary = {
      kg: Number(rows[0]?.kg) || 0,
      refuelCount: Number(rows[0]?.refuel_count) || 0,
      vehicleCount: Number(rows[0]?.vehicle_count) || 0,
      stationCount: Number(rows[0]?.station_count) || 0,
    };
  }
  const ranked = [...nearby].sort((left, right) => metricValue(right, metric) - metricValue(left, metric));
  return c.json({
    center: { lng: longitude, lat: latitude },
    radiusKm,
    kg: nearbySummary.kg,
    refuelCount: nearbySummary.refuelCount,
    vehicleCount: nearbySummary.vehicleCount,
    stationCount: nearbySummary.stationCount,
    topStations: ranked.slice(0, 10).map((row) => serializeStation(row, metric)),
  });
});

export default router;