import JSZip from 'jszip'
import * as FileSystem from 'expo-file-system'
import * as Sharing from 'expo-sharing'
import { getDatabase } from '../../db/database'
import type { SummaryRow } from './useSummaryData'

const BOM = '\uFEFF'

// 主 CSV 表头（含照片目录列）
const HEADERS = ['楼层', '标记点名', '物品名', '类别', '数量', '单价', '评估参考价格', '备注', '照片数', '照片目录']

// 照片索引 CSV 表头
const INDEX_HEADERS = ['物品ID', '楼层', '标记点', '物品名', '照片文件路径']

function escapeCsv(value: string | number): string {
  const str = String(value)
  if (str.includes(',') || str.includes('"') || str.includes('\n')) {
    return `"${str.replace(/"/g, '""')}"`
  }
  return str
}

function sanitizeDirName(name: string): string {
  return name.replace(/[\\/:*?"<>|]/g, '_').slice(0, 20)
}

function formatDate(d: Date): string {
  const pad = (n: number) => String(n).padStart(2, '0')
  return `${d.getFullYear()}${pad(d.getMonth() + 1)}${pad(d.getDate())}_${pad(d.getHours())}${pad(d.getMinutes())}`
}

async function getPhotoPathsByItem(itemId: number): Promise<string[]> {
  const db = getDatabase()
  const rows = await db.getAllAsync<{ filePath: string }>(
    `SELECT file_path as filePath FROM photos WHERE item_id = ? ORDER BY sort_order ASC`,
    [itemId],
  )
  return rows.map((r) => r.filePath)
}

// 仅导出 CSV 数据（不含照片）
export async function exportDataOnly(rows: SummaryRow[]): Promise<void> {
  const canShare = await Sharing.isAvailableAsync()
  if (!canShare) throw new Error('当前设备不支持分享功能')

  const DATA_HEADERS = ['楼层', '标记点名', '物品名', '类别', '数量', '单价', '评估参考价格', '备注', '照片数']

  const csvLines = [
    DATA_HEADERS.join(','),
    ...rows.map((r) =>
      [
        `${r.floor}F`,
        r.markerLabel || '—',
        r.name,
        r.category,
        r.quantity,
        r.estimatedValue > 0 ? r.estimatedValue : '',
        r.referencePrice > 0 ? r.referencePrice : '',
        r.remark,
        r.photoCount,
      ]
        .map(escapeCsv)
        .join(','),
    ),
  ]

  const csvContent = BOM + csvLines.join('\r\n')
  const csvPath = `${FileSystem.cacheDirectory}不动产摸底_${formatDate(new Date())}.csv`
  await FileSystem.writeAsStringAsync(csvPath, csvContent, {
    encoding: FileSystem.EncodingType.UTF8,
  })

  await Sharing.shareAsync(csvPath, {
    mimeType: 'text/csv',
    dialogTitle: '导出摸底数据（仅数据）',
  })
}

export async function exportWithPhotos(rows: SummaryRow[]): Promise<void> {
  const canShare = await Sharing.isAvailableAsync()
  if (!canShare) throw new Error('当前设备不支持分享功能')

  const zip = new JSZip()
  const photosFolder = zip.folder('photos')!

  // 照片索引行（每张照片一行）
  const indexLines: string[] = [INDEX_HEADERS.join(',')]

  // 为每个物品生成照片子目录名，并打包照片
  const photoDirMap = new Map<number, string>() // itemId → 子目录路径（相对 ZIP 根）

  for (const row of rows) {
    if (row.photoCount === 0) continue

    const paths = await getPhotoPathsByItem(row.itemId)
    if (paths.length === 0) continue

    const dirName = `${row.floor}F_${sanitizeDirName(row.markerLabel)}_${sanitizeDirName(row.name)}(${row.itemId})`
    const itemFolder = photosFolder.folder(dirName)!
    const relativeDirPath = `photos/${dirName}/`
    photoDirMap.set(row.itemId, relativeDirPath)

    for (let i = 0; i < paths.length; i++) {
      const filePath = paths[i]
      const photoFileName = `${i + 1}.jpg`
      const photoRelativePath = `${relativeDirPath}${photoFileName}`

      try {
        const info = await FileSystem.getInfoAsync(filePath)
        if (!info.exists) continue
        const base64 = await FileSystem.readAsStringAsync(filePath, {
          encoding: FileSystem.EncodingType.Base64,
        })
        itemFolder.file(photoFileName, base64, { base64: true })
      } catch {
        // 单张照片读取失败时跳过，不中断整体导出
        continue
      }

      // 写入索引行
      indexLines.push(
        [row.itemId, `${row.floor}F`, row.markerLabel, row.name, photoRelativePath]
          .map(escapeCsv)
          .join(','),
      )
    }
  }

  // 生成照片索引文件
  if (indexLines.length > 1) {
    photosFolder.file('index.csv', BOM + indexLines.join('\r\n'))
  }

  // 生成主 CSV（含照片目录列）
  const csvLines = [
    HEADERS.join(','),
    ...rows.map((r) =>
      [
        `${r.floor}F`,
        r.markerLabel || '—',
        r.name,
        r.category,
        r.quantity,
        r.estimatedValue > 0 ? r.estimatedValue : '',
        r.referencePrice > 0 ? r.referencePrice : '',
        r.remark,
        r.photoCount,
        photoDirMap.get(r.itemId) ?? '',
      ]
        .map(escapeCsv)
        .join(','),
    ),
  ]
  zip.file('摸底数据.csv', BOM + csvLines.join('\r\n'))

  // 生成 ZIP 并分享
  const zipBase64 = await zip.generateAsync({ type: 'base64' })
  const zipPath = `${FileSystem.cacheDirectory}不动产摸底_${formatDate(new Date())}.zip`
  await FileSystem.writeAsStringAsync(zipPath, zipBase64, {
    encoding: FileSystem.EncodingType.Base64,
  })

  await Sharing.shareAsync(zipPath, {
    mimeType: 'application/zip',
    dialogTitle: '导出不动产摸底数据',
  })
}