import { useState } from 'react'
import { usePageSize } from '../../hooks/usePageSize'
import { toast } from 'sonner'
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
import { useConfirm } from '../../hooks/useConfirm'
import { Calculator, Check, Layers, Settings as X, Download, Eye } from 'lucide-react'
import PageGuide from '../../components/ui/PageGuide'
import { payrollApi } from '../../lib/api-services'
import Card from '../../components/ui/Card'
import Button from '../../components/ui/Button'
import { Input, Label } from '../../components/ui/Input'
import Modal from '../../components/ui/Modal'
import Pagination from '../../components/ui/Pagination'
// 金额格式化：保留两位小数 + 千分位
const fmt = (n: number) => (n || 0).toLocaleString('zh-CN', { minimumFractionDigits: 2, maximumFractionDigits: 2 })

export function PayslipManager({ filterEmployeeId }: { filterEmployeeId?: string }) {
  const queryClient = useQueryClient()
  const confirm = useConfirm()
  const [month, setMonth] = useState(new Date().toISOString().slice(0, 7))
  const pageSize = usePageSize()
  const [page, setPage] = useState(1)
  const [showTaxPreview, setShowTaxPreview] = useState(false)
  const [previewData, setPreviewData] = useState({
    baseSalary: 0,
    overtimePay: 0,
    allowance: 0,
    deduction: 0,
    bonus: 0,
    specialDeduction: 0,
  })

  const { data: payslips, isLoading } = useQuery<any[]>({
    queryKey: ['payslips', month, filterEmployeeId],
    queryFn: async () => {
      const all = await payrollApi.payslips({ month })
      if (!filterEmployeeId) return all
      return all.filter((p: any) => p.employeeId === filterEmployeeId)
    },
  })

  const deleteMutation = useMutation({
    mutationFn: (id: string) => payrollApi.removePayslip(id),
    onSuccess: () => queryClient.invalidateQueries({ queryKey: ['payslips'] }),
  })

  const generateFromBatchMutation = useMutation({
    mutationFn: (data: any) => payrollApi.generatePayslips(data?.month || data),
    onSuccess: (res: any) => {
      queryClient.invalidateQueries({ queryKey: ['payslips'] })
      queryClient.invalidateQueries({ queryKey: ['dashboard'] })
      const n = res?.data?.generated || 0
      toast.success(`已从归档批次汇总生成 ${n} 条工资条并发布。`)
    },
  })

  const taxPreviewMutation = useMutation({
    mutationFn: (data: any) => payrollApi.taxPreview(data),
    onSuccess: (res: any) => {
      setTaxResult(res.data)
      setShowTaxPreview(true)
    },
  })

  const [taxResult, setTaxResult] = useState<any>(null)

  const confirmedCount = payslips?.filter((p: any) => p.confirmedAt).length || 0
  const unconfirmedCount = payslips ? payslips.length - confirmedCount : 0

  return (
    <div className="space-y-3">
      <div className="flex flex-wrap items-center justify-between gap-2">
        <div className="flex items-center gap-2">
          <Input type="month" value={month} onChange={(e) => setMonth(e.target.value)} className="w-48" />
          {payslips && payslips.length > 0 && (
            <div className="flex items-center gap-2 text-xs flex-nowrap">
              <span className="px-2 py-0.5 rounded bg-gray-100 text-gray-600 whitespace-nowrap">共 {payslips.length} 条</span>
              <span className="px-2 py-0.5 rounded bg-green-50 text-safe whitespace-nowrap">已确认 {confirmedCount}</span>
              <span className="px-2 py-0.5 rounded bg-amber-50 text-warning whitespace-nowrap">未确认 {unconfirmedCount}</span>
            </div>
          )}
        </div>
        <div className="flex gap-2">
          <Button
            variant="secondary"
            onClick={() => {
              if (!payslips || payslips.length === 0) {
                toast.error('暂无工资条可导出')
                return
              }
              const headers = ['员工', '部门', '基本工资', '加班费', '津贴', '奖金', '扣款', '应发合计', '个税', '实发', '确认状态']
              const rows = payslips.map((p: any) => [
                p.employee?.name || '',
                p.employee?.department || '',
                p.baseSalary || 0,
                p.overtimePay || 0,
                p.allowance || 0,
                p.bonus || 0,
                p.deduction || 0,
                p.totalPay || 0,
                p.tax || 0,
                p.netPay || 0,
                p.confirmedAt ? '已确认' : '未确认',
              ])
              const csv = [headers, ...rows].map(r => r.join(',')).join('\n')
              const blob = new Blob(['\uFEFF' + csv], { type: 'text/csv;charset=utf-8' })
              const url = URL.createObjectURL(blob)
              const a = document.createElement('a')
              a.href = url
              a.download = `工资表-${month}.csv`
              a.click()
              URL.revokeObjectURL(url)
              toast.success('已导出工资表')
            }}
          >
            <Download className="w-4 h-4 mr-1" />
            导出工资表
          </Button>
          <Button
            variant="secondary"
            onClick={() => {
              if (!payslips || payslips.length === 0) {
                toast.error('暂无工资条可导出')
                return
              }
              const headers = ['序号', '收款人姓名', '收款账号', '开户行', '金额', '用途', '备注']
              const rows = payslips.map((p: any, i: number) => [
                i + 1,
                p.employee?.name || '',
                p.employee?.bankAccount || '',
                p.employee?.bankName || '',
                (p.netPay || 0).toFixed(2),
                `${month}月工资`,
                '',
              ])
              const csv = [headers, ...rows].map(r => r.join(',')).join('\n')
              const blob = new Blob(['\uFEFF' + csv], { type: 'text/csv;charset=utf-8' })
              const url = URL.createObjectURL(blob)
              const a = document.createElement('a')
              a.href = url
              a.download = `工资流水-${month}.csv`
              a.click()
              URL.revokeObjectURL(url)
              toast.success('已导出工资流水')
            }}
          >
            <Download className="w-4 h-4 mr-1" />
            导出工资流水
          </Button>
          <Button
            onClick={() => setShowTaxPreview(true)}
          >
            <Calculator className="w-4 h-4 mr-1" />
            税率试算
          </Button>
          <Button
            onClick={async () => {
              if (await confirm({ title: '生成工资条', message: `确认从 ${month} 已归档批次汇总生成工资条？这将覆盖已有的工资条数据。`, variant: 'primary' })) {
                generateFromBatchMutation.mutate({ month })
              }
            }}
            disabled={generateFromBatchMutation.isPending}
          >
            <Layers className="w-4 h-4 mr-1" />
            {generateFromBatchMutation.isPending ? '生成中...' : '从批次汇总生成'}
          </Button>
        </div>
      </div>

      {isLoading ? (
        <div className="text-center py-8 text-gray-500">加载中...</div>
      ) : !payslips || payslips.length === 0 ? (
        <Card><div className="text-center py-8 text-gray-500">该月份暂无工资条记录</div></Card>
      ) : (
        <Card>
          <div className="overflow-x-auto">
            <table className="w-full text-sm">
              <thead>
                <tr className="border-b text-left text-xs text-gray-500">
                  <th className="py-2 px-2">员工</th>
                  <th className="py-2 px-2">部门</th>
                  <th className="py-2 px-2 text-right">基本工资</th>
                  <th className="py-2 px-2 text-right">加班费</th>
                  <th className="py-2 px-2 text-right">津贴</th>
                  <th className="py-2 px-2 text-right">奖金</th>
                  <th className="py-2 px-2 text-right">扣款</th>
                  <th className="py-2 px-2 text-right">应发合计</th>
                  <th className="py-2 px-2 text-right">个税</th>
                  <th className="py-2 px-2 text-right">实发</th>
                  <th className="py-2 px-2 text-center">确认状态</th>
                  <th className="py-2 px-2"></th>
                </tr>
              </thead>
              <tbody>
                {payslips.slice((page - 1) * pageSize, page * pageSize).map((p: any) => (
                  <tr key={p.id} className="border-b last:border-0 hover:bg-gray-50">
                    <td className="py-2 px-2 text-sm font-medium">
                      <div className="flex flex-col gap-0.5">
                        <span>{p.employee?.name}</span>
                        {p.employee?.idCardNumber && <span className="text-gray-400 text-[11px] font-mono">{p.employee.idCardNumber}</span>}
                      </div>
                    </td>
                    <td className="py-2 px-2 text-gray-500">{p.employee?.department}</td>
                    <td className="py-2 px-2 text-right">¥{fmt(p.baseSalary)}</td>
                    <td className="py-2 px-2 text-right">¥{fmt(p.overtimePay)}</td>
                    <td className="py-2 px-2 text-right">¥{fmt(p.allowance)}</td>
                    <td className="py-2 px-2 text-right">¥{fmt(p.bonus)}</td>
                    <td className="py-2 px-2 text-right text-danger">{p.deduction > 0 ? '-¥' + fmt(p.deduction) : '¥0'}</td>
                    <td className="py-2 px-2 text-right font-medium text-primary">¥{fmt(p.totalPay)}</td>
                    <td className="py-2 px-2 text-right text-danger">¥{fmt(p.tax)}</td>
                    <td className="py-2 px-2 text-right font-bold text-safe">¥{fmt(p.netPay)}</td>
                    <td className="py-2 px-2 text-center">
                      {p.confirmedAt ? (
                        <span className="inline-flex items-center gap-1 text-safe text-xs">
                          <Check className="w-3 h-3" />已确认
                        </span>
                      ) : p.viewedAt ? (
                        <span className="inline-flex items-center gap-1 text-blue-600 text-xs" title={`查看于 ${new Date(p.viewedAt).toLocaleString('zh-CN')}`}>
                          <Eye className="w-3 h-3" />已查看
                        </span>
                      ) : p.publishedAt ? (
                        <span className="inline-flex items-center gap-1 text-gray-400 text-xs">
                          <Check className="w-3 h-3" />已发送
                        </span>
                      ) : (
                        <span className="text-gray-400 text-xs">未发送</span>
                      )}
                    </td>
                    <td className="py-2 px-2">
                      <button
                        onClick={() => deleteMutation.mutate(p.id)}
                        className="text-xs text-gray-500 hover:text-danger"
                      >
                        删除
                      </button>
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
          <Pagination page={page} pageSize={pageSize} total={payslips.length} onPageChange={setPage} onPageSizeChange={() => setPage(1)} />
        </Card>
      )}

      {/* 税率试算 Modal */}
      {showTaxPreview && (
        <Modal open onClose={() => { setShowTaxPreview(false); setTaxResult(null) }}>
          <div className="space-y-4">
            <div className="flex items-center justify-between">
              <h3 className="font-medium">工资条税率试算</h3>
              <button onClick={() => { setShowTaxPreview(false); setTaxResult(null) }} className="text-gray-500 hover:text-gray-600">
                <X className="w-5 h-5" />
              </button>
            </div>

            <div className="grid grid-cols-2 gap-3">
              <div>
                <Label>基本工资</Label>
                <Input type="number" value={previewData.baseSalary || ''} onChange={(e) => setPreviewData({ ...previewData, baseSalary: Number(e.target.value) })} placeholder="请输入" />
              </div>
              <div>
                <Label>加班费</Label>
                <Input type="number" value={previewData.overtimePay || ''} onChange={(e) => setPreviewData({ ...previewData, overtimePay: Number(e.target.value) })} placeholder="请输入" />
              </div>
              <div>
                <Label>津贴</Label>
                <Input type="number" value={previewData.allowance || ''} onChange={(e) => setPreviewData({ ...previewData, allowance: Number(e.target.value) })} placeholder="请输入" />
              </div>
              <div>
                <Label>奖金</Label>
                <Input type="number" value={previewData.bonus || ''} onChange={(e) => setPreviewData({ ...previewData, bonus: Number(e.target.value) })} placeholder="请输入" />
              </div>
              <div>
                <Label>扣款</Label>
                <Input type="number" value={previewData.deduction || ''} onChange={(e) => setPreviewData({ ...previewData, deduction: Number(e.target.value) })} placeholder="请输入" />
              </div>
              <div>
                <Label>专项附加扣除</Label>
                <Input type="number" value={previewData.specialDeduction || ''} onChange={(e) => setPreviewData({ ...previewData, specialDeduction: Number(e.target.value) })} placeholder="请输入" />
              </div>
            </div>

            <div className="flex gap-2">
              <Button onClick={() => taxPreviewMutation.mutate({ month, ...previewData })} disabled={taxPreviewMutation.isPending} className="flex-1">
                {taxPreviewMutation.isPending ? '计算中...' : '计算'}
              </Button>
              <Button variant="secondary" onClick={() => {
                setPreviewData({ baseSalary: 0, overtimePay: 0, allowance: 0, deduction: 0, bonus: 0, specialDeduction: 0 })
                setTaxResult(null)
              }}>
                重置
              </Button>
            </div>

            {taxResult && (
              <div className="border rounded-md p-3 space-y-2">
                <div className="text-xs font-medium text-gray-600 mb-2">计算结果</div>
                {taxResult.breakdown.map((item: any, i: number) => (
                  <div key={i} className={`flex justify-between text-xs ${i === taxResult.breakdown.length - 1 ? 'font-bold border-t pt-2 mt-2' : ''} ${item.value < 0 ? 'text-danger' : item.value > 0 && i < taxResult.breakdown.length - 1 ? 'text-gray-500' : ''}`}>
                    <span>{item.label}</span>
                    <span>{item.value < 0 ? `-¥${fmt(Math.abs(item.value))}` : `¥${fmt(item.value)}`}</span>
                  </div>
                ))}
                {taxResult.ytdPayslipCount > 0 && (
                  <div className="text-xs text-gray-500 mt-2">注：已累计{taxResult.ytdPayslipCount}条工资条计算个税</div>
                )}
              </div>
            )}
          </div>
        </Modal>
      )}
    </div>
  )
}

