import { Router, Response } from 'express'
import { authMiddleware, AuthRequest } from '../middleware/auth'
import { requireAdmin } from '../middleware/rbac'
import prisma from '../lib/prisma'
import { decrypt } from '../lib/crypto'
import ExcelJS from 'exceljs'
import { createGzip } from 'zlib'
import { Writable } from 'stream'

const router = Router()

// RFC 5987 编码中文文件名，兼容所有浏览器
function contentDisposition(filename: string): string {
  const encoded = encodeURIComponent(filename)
  return `attachment; filename="${encoded}"; filename*=UTF-8''${encoded}`
}

// 敏感字段脱敏
function maskIdCard(idCard: string | null): string | null {
  if (!idCard) return null
  if (idCard.length >= 11) return idCard.slice(0, 3) + '*'.repeat(idCard.length - 7) + idCard.slice(-4)
  return idCard
}
function maskBankAccount(account: string | null): string | null {
  if (!account) return null
  if (account.length > 4) return '*'.repeat(account.length - 4) + account.slice(-4)
  return account
}

// 导出全部数据（支持模块选择、格式选择、脱敏）
router.get('/all', authMiddleware, requireAdmin, async (req: AuthRequest, res: Response, next) => {
  try {
    const orgId = req.user!.orgId
    const format = (req.query.format as string) || 'json'
    const mask = req.query.mask === 'true' || req.user!.role !== 'ADMIN'
    const modules = (req.query.modules as string || 'employees,contracts,terminations,payrollBatches,payslips,socialRecords,housingRecords,riskItems').split(',')

    const exportBatchSize = 500
    const fetchMap: Record<string, () => Promise<any[]>> = {
      employees: () => prisma.employee.findMany({ where: { orgId }, take: exportBatchSize }),
      contracts: () => prisma.laborContract.findMany({ where: { orgId }, take: exportBatchSize }),
      terminations: () => prisma.terminationRecord.findMany({ where: { orgId }, take: exportBatchSize }),
      payrollBatches: () => prisma.payrollBatch.findMany({ where: { orgId }, take: exportBatchSize }),
      payslips: () => prisma.payslip.findMany({ where: { orgId }, take: exportBatchSize }),
      socialRecords: () => prisma.employeeSocialInsRecord.findMany({ where: { orgId }, take: exportBatchSize }),
      housingRecords: () => prisma.employeeHousingFundRecord.findMany({ where: { orgId }, take: exportBatchSize }),
      riskItems: () => prisma.riskItem.findMany({ where: { orgId }, take: exportBatchSize }),
    }

    const useGzip = req.query.gzip !== 'false'
    const batchSize = 500

    if (format === 'excel') {
      const data: any = { exportedAt: new Date().toISOString(), orgId }

      if (modules.includes('employees')) {
        const employees = await fetchMap.employees()
        data.employees = employees.map((e: any) => {
          let salary = 0
          try { salary = Number(decrypt(e.monthlySalary)) || 0 } catch { salary = Number(e.monthlySalary) || 0 }
          let idCard: string | null = null
          try { if (e.idCardNumber) idCard = decrypt(e.idCardNumber) } catch { idCard = e.idCardNumber }
          let bankAccount: string | null = null
          try { if (e.bankAccount) bankAccount = decrypt(e.bankAccount) } catch { bankAccount = e.bankAccount }
          if (mask) {
            idCard = maskIdCard(idCard)
            bankAccount = maskBankAccount(bankAccount)
            if (salary) salary = 0
          }
          return { ...e, monthlySalary: salary, idCardNumber: idCard, bankAccount }
        })
      }

      for (const mod of modules) {
        if (mod === 'employees') continue
        if (fetchMap[mod]) {
          data[mod] = await fetchMap[mod]()
        }
      }

      const workbook = new ExcelJS.Workbook()
      for (const mod of modules) {
        if (!data[mod] || !data[mod].length) continue
        const ws = workbook.addWorksheet(mod.slice(0, 31))
        const rows = data[mod]
        const keys = Object.keys(rows[0]).filter(k => typeof rows[0][k] !== 'object')
        ws.columns = keys.map(k => ({ header: k, key: k, width: 18 }))
        ws.getRow(1).font = { bold: true }
        for (const row of rows) {
          const flat: any = {}
          for (const k of keys) flat[k] = typeof row[k] === 'object' ? JSON.stringify(row[k]) : row[k]
          ws.addRow(flat)
        }
      }
      res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
      res.setHeader('Content-Disposition', contentDisposition(`导出数据-${new Date().toISOString().slice(0, 10)}.xlsx`))
      await workbook.xlsx.write(res)
      res.end()
    } else {
      // JSON 流式导出 + gzip 压缩
      if (useGzip) {
        res.setHeader('Content-Encoding', 'gzip')
        res.setHeader('Content-Type', 'application/json')
        res.setHeader('Content-Disposition', contentDisposition(`导出数据-${new Date().toISOString().slice(0, 10)}.json.gz`))
      } else {
        res.setHeader('Content-Type', 'application/json')
        res.setHeader('Content-Disposition', contentDisposition(`导出数据-${new Date().toISOString().slice(0, 10)}.json`))
      }

      const gzip = useGzip ? createGzip() : null
      const output: Writable = gzip || res
      if (gzip) { gzip.pipe(res) }

      const write = (chunk: string) => {
        output.write(Buffer.from(chunk))
      }

      write('{"exportedAt":"' + new Date().toISOString() + '","orgId":"' + orgId + '"')

      for (const mod of modules) {
        write(',"' + mod + '":[')

        if (mod === 'employees') {
          // 员工数据分批查询，避免内存溢出
          let skip = 0
          let first = true
          while (true) {
            const batch = await prisma.employee.findMany({ where: { orgId }, skip, take: batchSize })
            if (batch.length === 0) break
            for (const e of batch) {
              let salary = 0
              try { salary = Number(decrypt(e.monthlySalary)) || 0 } catch { salary = Number(e.monthlySalary) || 0 }
              let idCard: string | null = null
              try { if (e.idCardNumber) idCard = decrypt(e.idCardNumber) } catch { idCard = e.idCardNumber }
              let bankAccount: string | null = null
              try { if (e.bankAccount) bankAccount = decrypt(e.bankAccount) } catch { bankAccount = e.bankAccount }
              if (mask) {
                idCard = maskIdCard(idCard)
                bankAccount = maskBankAccount(bankAccount)
                if (salary) salary = 0
              }
              const row = { ...e, monthlySalary: salary, idCardNumber: idCard, bankAccount }
              write((first ? '' : ',') + JSON.stringify(row))
              first = false
            }
            skip += batchSize
            if (batch.length < batchSize) break
          }
        } else if (fetchMap[mod]) {
          const rows = await fetchMap[mod]()
          for (let i = 0; i < rows.length; i++) {
            write((i === 0 ? '' : ',') + JSON.stringify(rows[i]))
          }
        }

        write(']')
      }

      write('}')
      if (gzip) gzip.end()
      else res.end()
    }
  } catch (err) {
    next(err)
  }
})

// 导出本月薪税汇总 Excel
router.get('/payroll', authMiddleware, async (req: AuthRequest, res: Response, next) => {
  try {
    const orgId = req.user!.orgId
    const month = (req.query.month as string) || new Date().toISOString().slice(0, 7)

    const entries = await prisma.batchEntry.findMany({
      where: { orgId, batch: { month, status: 'ARCHIVED' } },
      include: { employee: true, batch: true },
      orderBy: { employee: { name: 'asc' } },
    })

    const workbook = new ExcelJS.Workbook()
    const ws = workbook.addWorksheet('薪税汇总')

    ws.columns = [
      { header: '员工姓名', key: 'name', width: 12 },
      { header: '部门', key: 'department', width: 15 },
      { header: '基本工资', key: 'baseSalary', width: 12 },
      { header: '加班费', key: 'overtimePay', width: 12 },
      { header: '津贴补贴', key: 'allowance', width: 12 },
      { header: '奖金', key: 'bonus', width: 12 },
      { header: '扣款', key: 'deduction', width: 12 },
      { header: '应发合计', key: 'totalPay', width: 12 },
      { header: '个人社保', key: 'socialEmp', width: 12 },
      { header: '个人公积金', key: 'housingEmp', width: 12 },
      { header: '个人所得税', key: 'tax', width: 12 },
      { header: '实发工资', key: 'netPay', width: 12 },
      { header: '企业社保', key: 'socialOrg', width: 12 },
      { header: '企业公积金', key: 'housingOrg', width: 12 },
      { header: '企业总成本', key: 'orgCost', width: 12 },
    ]

    ws.getRow(1).font = { bold: true }

    for (const e of entries) {
      ws.addRow({
        name: e.employee.name,
        department: e.employee.department,
        baseSalary: e.baseSalary,
        overtimePay: e.overtimePay,
        allowance: e.allowance,
        bonus: e.bonus,
        deduction: e.deduction,
        totalPay: e.totalPay,
        socialEmp: e.socialEmp,
        housingEmp: e.housingEmp,
        tax: e.tax,
        netPay: e.netPay,
        socialOrg: e.socialOrg,
        housingOrg: e.housingOrg,
        orgCost: e.totalPay + e.socialOrg + e.housingOrg,
      })
    }

    // 汇总行
    const totalRow = ws.addRow({
      name: '合计',
      baseSalary: { formula: `SUM(C2:C${entries.length + 1})` },
      overtimePay: { formula: `SUM(D2:D${entries.length + 1})` },
      allowance: { formula: `SUM(E2:E${entries.length + 1})` },
      bonus: { formula: `SUM(F2:F${entries.length + 1})` },
      deduction: { formula: `SUM(G2:G${entries.length + 1})` },
      totalPay: { formula: `SUM(H2:H${entries.length + 1})` },
      socialEmp: { formula: `SUM(I2:I${entries.length + 1})` },
      housingEmp: { formula: `SUM(J2:J${entries.length + 1})` },
      tax: { formula: `SUM(K2:K${entries.length + 1})` },
      netPay: { formula: `SUM(L2:L${entries.length + 1})` },
      socialOrg: { formula: `SUM(M2:M${entries.length + 1})` },
      housingOrg: { formula: `SUM(N2:N${entries.length + 1})` },
      orgCost: { formula: `SUM(O2:O${entries.length + 1})` },
    })
    totalRow.font = { bold: true }

    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
    res.setHeader('Content-Disposition', contentDisposition(`薪税汇总-${month}.xlsx`))
    await workbook.xlsx.write(res)
    res.end()
  } catch (err) {
    next(err)
  }
})

// 导出花名册 Excel（支持筛选）
router.get('/roster', authMiddleware, async (req: AuthRequest, res: Response, next) => {
  try {
    const orgId = req.user!.orgId
    const search = req.query.search as string | undefined
    const status = req.query.status as string | undefined
    const department = req.query.department as string | undefined

    const where: any = { orgId }
    if (department) where.department = department
    if (status === 'RESIGNED') {
      where.status = 'RESIGNED'
    } else if (status === 'ACTIVE') {
      where.status = 'ACTIVE'
    }
    if (search) {
      where.OR = [
        { name: { contains: search } },
        { department: { contains: search } },
      ]
    }

    const employees = await prisma.employee.findMany({
      where,
      include: {
        contracts: { orderBy: { createdAt: 'desc' }, take: 1 },
      },
      orderBy: { createdAt: 'desc' },
    })

    const workbook = new ExcelJS.Workbook()
    const ws = workbook.addWorksheet('花名册')
    ws.columns = [
      { header: '姓名', key: 'name', width: 10 },
      { header: '部门', key: 'department', width: 12 },
      { header: '性别', key: 'gender', width: 6 },
      { header: '状态', key: 'status', width: 8 },
      { header: '入职日期', key: 'hireDate', width: 12 },
      { header: '手机号', key: 'phone', width: 13 },
      { header: '证件号码', key: 'idCardNumber', width: 20 },
      { header: '月工资', key: 'monthlySalary', width: 10 },
      { header: '社保基数', key: 'socialInsBase', width: 10 },
      { header: '公积金基数', key: 'housingFundBase', width: 10 },
      { header: '专项附加扣除', key: 'specialDeduction', width: 12 },
      { header: '参保城市', key: 'city', width: 10 },
      { header: '紧急联系人', key: 'emergencyContact', width: 10 },
      { header: '紧急联系电话', key: 'emergencyPhone', width: 13 },
      { header: '住址', key: 'address', width: 18 },
      { header: '开户行', key: 'bankName', width: 10 },
      { header: '银行账号', key: 'bankAccount', width: 18 },
      { header: '合同起始', key: 'contractStart', width: 12 },
      { header: '合同结束', key: 'contractEnd', width: 12 },
    ]
    ws.getRow(1).font = { bold: true }

    // 是否脱敏（非 ADMIN 用户强制脱敏）
    const shouldMask = req.user!.role !== 'ADMIN'

    for (const e of employees) {
      const contract = e.contracts[0]
      // 解密敏感字段
      let salary = 0
      try { salary = Number(decrypt(e.monthlySalary)) || 0 } catch { salary = Number(e.monthlySalary) || 0 }
      let idCard: string | null = null
      try { if (e.idCardNumber) idCard = decrypt(e.idCardNumber) } catch { idCard = e.idCardNumber }
      let bankAccount: string | null = null
      try { if (e.bankAccount) bankAccount = decrypt(e.bankAccount) } catch { bankAccount = e.bankAccount }
      if (shouldMask) {
        idCard = maskIdCard(idCard)
        bankAccount = maskBankAccount(bankAccount)
        if (salary) salary = 0
      }
      ws.addRow({
        name: e.name,
        department: e.department,
        gender: e.gender || '',
        status: e.status === 'ACTIVE' ? '在职' : e.status === 'RESIGNED' ? '离职' : '预入职',
        hireDate: e.hireDate?.toISOString().slice(0, 10) || '',
        phone: e.phone || '',
        idCardNumber: idCard || '',
        monthlySalary: salary,
        socialInsBase: e.socialInsBase || 0,
        housingFundBase: e.housingFundBase || 0,
        specialDeduction: e.specialDeduction || 0,
        city: e.city || '',
        emergencyContact: e.emergencyContact || '',
        emergencyPhone: e.emergencyPhone || '',
        address: e.address || '',
        bankName: e.bankName || '',
        bankAccount: bankAccount || '',
        contractStart: contract?.startDate?.toISOString().slice(0, 10) || '',
        contractEnd: contract?.endDate?.toISOString().slice(0, 10) || '',
      })
    }

    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
    res.setHeader('Content-Disposition', contentDisposition(`花名册-${new Date().toISOString().slice(0, 10)}.xlsx`))
    await workbook.xlsx.write(res)
    res.end()
  } catch (err) {
    next(err)
  }
})

// 导出解聘记录 Excel（支持筛选）
router.get('/terminations', authMiddleware, async (req: AuthRequest, res: Response, next) => {
  try {
    const orgId = req.user!.orgId
    const status = req.query.status as string | undefined
    const department = req.query.department as string | undefined
    const search = req.query.search as string | undefined
    const dateFrom = req.query.dateFrom as string | undefined
    const dateTo = req.query.dateTo as string | undefined

    const where: any = { orgId }
    if (status) where.status = status
    if (dateFrom || dateTo) {
      where.terminationDate = {}
      if (dateFrom) where.terminationDate.gte = new Date(dateFrom)
      if (dateTo) where.terminationDate.lte = new Date(dateTo + 'T23:59:59')
    }
    if (department || search) {
      where.employee = {}
      if (department) where.employee.department = department
      if (search) {
        where.employee.OR = [
          { name: { contains: search } },
          { department: { contains: search } },
        ]
      }
    }

    const records = await prisma.terminationRecord.findMany({
      where,
      include: { employee: true },
      orderBy: { updatedAt: 'desc' },
    })

    const workbook = new ExcelJS.Workbook()
    const ws = workbook.addWorksheet('解聘记录')
    ws.columns = [
      { header: '员工姓名', key: 'name', width: 12 },
      { header: '部门', key: 'department', width: 15 },
      { header: '解聘类型', key: 'type', width: 12 },
      { header: '解聘原因', key: 'reason', width: 20 },
      { header: '解聘日期', key: 'terminationDate', width: 12 },
      { header: '补偿金', key: 'compensation', width: 12 },
      { header: '状态', key: 'status', width: 10 },
      { header: '创建日期', key: 'createdAt', width: 12 },
    ]
    ws.getRow(1).font = { bold: true }

    const reasonLabels: Record<string, string> = {
      NEGOTIATED: '协商解除', FAULT: '过错解除', NONFAULT: '非过错解除',
      LAYOFF: '经济性裁员', EXPIRED: '合同到期', ILLEGAL: '违法解除', RESIGNATION: '员工离职',
    }
    const statusLabels: Record<string, string> = {
      DRAFT: '草稿', PENDING_APPROVAL: '待审批', APPROVED: '已审批',
      REJECTED: '已驳回', EXECUTING: '执行中', COMPLETED: '已完成', CANCELLED: '已撤销',
    }

    for (const r of records) {
      ws.addRow({
        name: r.employee.name,
        department: r.employee.department,
        type: r.type === 'TERMINATION' ? '解聘' : '离职',
        reason: reasonLabels[r.reason] || r.reason,
        terminationDate: r.terminationDate?.toISOString().slice(0, 10) || '',
        compensation: r.compensation || 0,
        status: statusLabels[r.status] || r.status,
        createdAt: r.createdAt?.toISOString().slice(0, 10) || '',
      })
    }

    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
    res.setHeader('Content-Disposition', contentDisposition(`解聘记录-${new Date().toISOString().slice(0, 10)}.xlsx`))
    await workbook.xlsx.write(res)
    res.end()
  } catch (err) {
    next(err)
  }
})

// 导出个税申报表 Excel（对齐自然人电子税务局格式）
router.get('/tax-declaration', authMiddleware, requireAdmin, async (req: AuthRequest, res: Response, next) => {
  try {
    const orgId = req.user!.orgId
    const month = (req.query.month as string) || new Date().toISOString().slice(0, 7)

    const entries = await prisma.batchEntry.findMany({
      where: { orgId, batch: { month, status: 'ARCHIVED' } },
      include: { employee: true, batch: true },
      orderBy: { employee: { name: 'asc' } },
    })

    const workbook = new ExcelJS.Workbook()
    const ws = workbook.addWorksheet('个税申报表')

    // 个税申报表列定义（对齐自然人电子税务局模板）
    ws.columns = [
      { header: '序号', key: 'seq', width: 6 },
      { header: '姓名', key: 'name', width: 10 },
      { header: '身份证件号码', key: 'idCardNumber', width: 22 },
      { header: '所得项目', key: 'incomeType', width: 16 },
      { header: '本期收入', key: 'totalPay', width: 12 },
      { header: '本期免税收入', key: 'taxFreeIncome', width: 14 },
      { header: '基本减除费用', key: 'basicDeduction', width: 14 },
      { header: '专项扣除合计', key: 'specialDeductionTotal', width: 14 },
      { header: '养老保险', key: 'pensionEmp', width: 10 },
      { header: '医疗保险', key: 'medicalEmp', width: 10 },
      { header: '失业保险', key: 'unemploymentEmp', width: 10 },
      { header: '住房公积金', key: 'housingEmp', width: 12 },
      { header: '专项附加扣除', key: 'specialAdditionalDeduction', width: 14 },
      { header: '其他扣除', key: 'otherDeduction', width: 10 },
      { header: '累计收入额', key: 'ytdIncome', width: 12 },
      { header: '累计减除费用', key: 'ytdBasicDeduction', width: 14 },
      { header: '累计专项扣除', key: 'ytdSpecialDeduction', width: 14 },
      { header: '累计专项附加扣除', key: 'ytdSpecialAdditional', width: 16 },
      { header: '累计应纳税所得额', key: 'ytdTaxableIncome', width: 16 },
      { header: '税率', key: 'taxRate', width: 8 },
      { header: '速算扣除数', key: 'quickDeduction', width: 12 },
      { header: '累计已预扣税额', key: 'ytdTaxDeducted', width: 14 },
      { header: '本期应预扣税额', key: 'tax', width: 14 },
      { header: '备注', key: 'remark', width: 20 },
    ]
    ws.getRow(1).font = { bold: true }

    let seq = 0
    for (const e of entries) {
      seq++
      // 解密证件号码
      let idCard: string = ''
      try { if (e.employee.idCardNumber) idCard = decrypt(e.employee.idCardNumber) || '' } catch { idCard = e.employee.idCardNumber || '' }

      // 从社保中拆分个人部分（简化：使用 socialEmp 总额按比例拆分）
      const socialEmp = e.socialEmp || 0
      const pensionEmp = Math.round(socialEmp * 0.56) // 养老约 56%
      const medicalEmp = Math.round(socialEmp * 0.36) // 医疗约 36%
      const unemploymentEmp = socialEmp - pensionEmp - medicalEmp // 剩余为失业

      // 累计数据
      const ytdTaxDeducted = (e as any).ytdTaxDeducted || e.tax || 0

      ws.addRow({
        seq,
        name: e.employee.name,
        idCardNumber: idCard,
        incomeType: '工资薪金所得',
        totalPay: e.totalPay || 0,
        taxFreeIncome: 0,
        basicDeduction: 5000, // 基本减除费用 5000/月
        specialDeductionTotal: socialEmp + (e.housingEmp || 0),
        pensionEmp,
        medicalEmp,
        unemploymentEmp,
        housingEmp: e.housingEmp || 0,
        specialAdditionalDeduction: e.employee.specialDeduction || 0,
        otherDeduction: 0,
        ytdIncome: e.totalPay || 0, // 简化：单月累计=本月
        ytdBasicDeduction: 5000,
        ytdSpecialDeduction: socialEmp + (e.housingEmp || 0),
        ytdSpecialAdditional: e.employee.specialDeduction || 0,
        ytdTaxableIncome: Math.max(0, (e.totalPay || 0) - 5000 - socialEmp - (e.housingEmp || 0) - (e.employee.specialDeduction || 0)),
        taxRate: '',
        quickDeduction: 0,
        ytdTaxDeducted,
        tax: e.tax || 0,
        remark: '',
      })
    }

    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
    res.setHeader('Content-Disposition', contentDisposition(`个税申报表-${month}.xlsx`))
    await workbook.xlsx.write(res)
    res.end()
  } catch (err) {
    next(err)
  }
})

export default router