import * as XLSX from 'xlsx';
import type { MonitoringVehicle } from './types';

interface ExportContext {
  date?: string;
  startDate?: string;
  endDate?: string;
  sortBy: 'today' | 'total';
}

const HEADERS = [
  '状态', '车牌号', '客户', '业务部门', '项目', '租赁状态',
  '运营区域', '区间里程(km)', '累计里程(km)',
] as const;

function statusLabel(v: MonitoringVehicle): string {
  if (!v.isDataSynced) return '未对接';
  return v.isOnline ? '在线' : '离线';
}

function mileageCell(v: MonitoringVehicle, kind: 'today' | 'total'): string | number {
  if (kind === 'today') {
    // 区间内未对接但有历史累计，视作区间 0；只有完全无数据才标「未对接」。
    if (!v.isDataSynced && v.totalKm == null) return '未对接';
    return Math.max(0, v.dailyKm || 0);
  }
  return v.totalKm != null ? v.totalKm : '未对接';
}

export function exportMileageXlsx(vehicles: MonitoringVehicle[], ctx: ExportContext): void {
  const start = ctx.startDate || ctx.date || '';
  const end = ctx.endDate || ctx.date || '';
  const isRange = !!start && !!end && start !== end;
  const summaryData: (string | number)[][] = [
    [...HEADERS],
    ...vehicles.map(v => [
      statusLabel(v),
      v.plate,
      v.customer || '',
      v.department || '',
      v.project || '',
      v.rentStatus || '',
      v.region || '',
      mileageCell(v, 'today'),
      mileageCell(v, 'total'),
    ]),
  ];

  const ws = XLSX.utils.aoa_to_sheet(summaryData);

  ws['!cols'] = [
    { wch: 8 },   // 状态
    { wch: 12 },  // 车牌号
    { wch: 28 },  // 客户
    { wch: 14 },  // 业务部门
    { wch: 16 },  // 项目
    { wch: 10 },  // 租赁状态
    { wch: 12 },  // 运营区域
    { wch: 14 },  // 区间里程
    { wch: 14 },  // 累计里程
  ];

  ws['!freeze'] = { xSplit: 0, ySplit: 1 } as never;

  for (let r = 1; r < summaryData.length; r++) {
    for (const c of [7, 8]) {
      const ref = XLSX.utils.encode_cell({ r, c });
      if (ws[ref]?.t === 'n') ws[ref].z = '0.##########';
    }
  }

  // 表头样式（在客户端 SheetJS 社区版仅基本样式生效）
  for (let c = 0; c < HEADERS.length; c++) {
    const ref = XLSX.utils.encode_cell({ r: 0, c });
    if (ws[ref]) {
      (ws[ref] as { s?: unknown }).s = {
        font: { bold: true, color: { rgb: 'FFFFFF' } },
        fill: { fgColor: { rgb: '2563EB' } },
        alignment: { horizontal: 'center', vertical: 'center' },
      };
    }
  }

  const wb = XLSX.utils.book_new();
  XLSX.utils.book_append_sheet(wb, ws, '车辆汇总');

  const dayKeys = Array.from(
    new Set(vehicles.flatMap(v => Object.keys(v.dailyMileage || {})))
  ).sort();
  if (dayKeys.length > 0) {
    const detailHeaders = [
      '车牌号', '客户', '业务部门', '项目', '租赁状态', '运营区域',
      ...dayKeys.map(day => `${day}里程(km)`),
      '区间合计(km)',
      '累计里程(km)',
    ];
    const detailData: (string | number)[][] = [
      detailHeaders,
      ...vehicles.map(v => [
        v.plate,
        v.customer || '',
        v.department || '',
        v.project || '',
        v.rentStatus || '',
        v.region || '',
        ...dayKeys.map(day => v.dailyMileage?.[day] || 0),
        Math.max(0, v.dailyKm || 0),
        v.totalKm != null ? v.totalKm : '',
      ]),
    ];
    const detailWs = XLSX.utils.aoa_to_sheet(detailData);
    detailWs['!cols'] = [
      { wch: 12 },
      { wch: 28 },
      { wch: 14 },
      { wch: 16 },
      { wch: 10 },
      { wch: 12 },
      ...dayKeys.map(() => ({ wch: 14 })),
      { wch: 14 },
      { wch: 14 },
    ];
    detailWs['!freeze'] = { xSplit: 6, ySplit: 1 } as never;
    for (let r = 1; r < detailData.length; r++) {
      for (let c = 6; c < detailHeaders.length; c++) {
        const ref = XLSX.utils.encode_cell({ r, c });
        if (detailWs[ref]?.t === 'n') detailWs[ref].z = '0.##########';
      }
    }
    XLSX.utils.book_append_sheet(wb, detailWs, '每日明细');
  }

  const now = new Date();
  const y = now.getFullYear();
  const m = String(now.getMonth() + 1).padStart(2, '0');
  const d = String(now.getDate()).padStart(2, '0');
  const hh = String(now.getHours()).padStart(2, '0');
  const mm = String(now.getMinutes()).padStart(2, '0');
  const dateTag = start && end
    ? `${start.replace(/-/g, '')}-${end.replace(/-/g, '')}`
    : `${y}${m}${d}`;
  const filename = `里程看板_${dateTag}_${hh}${mm}_${ctx.sortBy === 'today' ? (isRange ? '区间' : '今日') : '累计'}.xlsx`;
  XLSX.writeFile(wb, filename);
}