import { Hono } from 'hono';
import pool from '../../db.js';
import mileagePool from '../../mileage-db.js';

const app = new Hono();

app.get('/', async (c) => {
  const targetId = c.req.query('targetId');
  const days = Number(c.req.query('days')) || 7;

  try {
    let plates: string[] = [];
    if (targetId) {
      const [vehicleRows] = await pool.execute(
        'SELECT plate_number FROM lingniu_prod.tab_mileage_assessment_vehicle WHERE target_id = ? AND is_deleted = 0',
        [targetId]
      ) as [{ plate_number: string }[], unknown];
      plates = vehicleRows.map(r => r.plate_number);
      if (plates.length === 0) return c.json([]);
    }

    // 单车日里程负值视为脏数据（里程表回滚 / 换 GPS 设备），不纳入统计
    let sql = `
      SELECT DATE_FORMAT(stat_date, '%m-%d') as date,
             SUM(IF(daily_km < 0, 0, daily_km)) as mileage
      FROM v_vehicle_daily_stats
      WHERE stat_date >= DATE_SUB(CURDATE(), INTERVAL ? DAY) AND stat_date < CURDATE()
    `;
    const params: (string | number)[] = [days];

    if (plates.length > 0) {
      sql += ` AND plate IN (${plates.map(() => '?').join(',')})`;
      params.push(...plates);
    }

    sql += ' GROUP BY stat_date ORDER BY stat_date';

    const [rows] = await mileagePool.execute(sql, params) as [any[], unknown];

    return c.json(rows.map((r: any) => ({
      date: r.date,
      mileage: Math.round(Number(r.mileage) || 0),
    })));
  } catch (e: unknown) {
    console.error('trend error:', e);
    return c.json([], 500);
  }
});

export default app;