'use client'

import { useState, useEffect } from 'react'
import { Button } from '@/components/ui/button'
import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogTrigger } from '@/components/ui/dialog'
import { Input } from '@/components/ui/input'
import { Badge } from '@/components/ui/badge'
import { Search, Check } from 'lucide-react'
import { 
  ColumnDef,
  flexRender,
  getCoreRowModel,
  getFilteredRowModel,
  getPaginationRowModel,
  getSortedRowModel,
  useReactTable,
  SortingState,
  ColumnFiltersState,
  VisibilityState,
  RowSelectionState,
} from '@tanstack/react-table'
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table'
import { getContracts } from '../actions/data-actions'
import { toast } from 'sonner'

interface Contract {
  id: number
  contractNo: string
  contractName: string
  status: string
  projectId: number
  vendorId: number
  projectCode: string | null
  projectName: string | null
  vendorName: string | null
  vendorCode: string | null
}

interface ContractSelectorProps {
  selectedContract?: Contract
  onContractSelect: (contract: Contract) => void
  disabled?: boolean
  preselectedContractId?: number
}

export function ContractSelector({ selectedContract, onContractSelect, disabled, preselectedContractId }: ContractSelectorProps) {
  const [open, setOpen] = useState(false)
  const [contracts, setContracts] = useState<Contract[]>([])
  const [loading, setLoading] = useState(false)
  const [sorting, setSorting] = useState<SortingState>([])
  const [columnFilters, setColumnFilters] = useState<ColumnFiltersState>([])
  const [columnVisibility, setColumnVisibility] = useState<VisibilityState>({})
  const [rowSelection, setRowSelection] = useState<RowSelectionState>({})
  const [globalFilter, setGlobalFilter] = useState('')

  const columns: ColumnDef<Contract>[] = [
    {
      accessorKey: 'contractNo',
      header: '계약번호',
      cell: ({ row }) => (
        <div className="font-mono text-sm">{row.getValue('contractNo')}</div>
      ),
    },
    {
      accessorKey: 'contractName',
      header: '계약명',
      cell: ({ row }) => (
        <div className="max-w-[300px] truncate">{row.getValue('contractName')}</div>
      ),
    },
    {
      accessorKey: 'status',
      header: '상태',
      cell: ({ row }) => {
        const status = row.getValue('status') as string
        const getStatusColor = (status: string) => {
          switch (status) {
            case 'ACTIVE': return 'bg-green-100 text-green-800'
            case 'TEST': return 'bg-blue-100 text-blue-800'
            case 'DRAFT': return 'bg-yellow-100 text-yellow-800'
            case 'PENDING': return 'bg-orange-100 text-orange-800'
            default: return 'bg-gray-100 text-gray-800'
          }
        }
        return (
          <Badge className={getStatusColor(status)}>
            {status}
          </Badge>
        )
      },
    },
    {
      accessorKey: 'projectCode',
      header: '프로젝트',
      cell: ({ row }) => {
        const projectCode = row.getValue('projectCode') as string | null
        const projectName = row.original.projectName
        return projectCode ? (
          <div>
            <div className="font-mono text-sm">{projectCode}</div>
            {projectName && (
              <div className="text-xs text-muted-foreground truncate max-w-[150px]">
                {projectName}
              </div>
            )}
          </div>
        ) : (
          <span className="text-muted-foreground">-</span>
        )
      },
    },
    {
      accessorKey: 'vendorName',
      header: '벤더',
      cell: ({ row }) => {
        const vendorName = row.getValue('vendorName') as string | null
        const vendorCode = row.original.vendorCode
        return vendorName ? (
          <div>
            <div className="font-medium text-sm">{vendorName}</div>
            {vendorCode && (
              <div className="text-xs text-muted-foreground font-mono">
                {vendorCode}
              </div>
            )}
          </div>
        ) : (
          <span className="text-muted-foreground">-</span>
        )
      },
    },
    {
      id: 'actions',
      header: '선택',
      cell: ({ row }) => (
        <Button
          variant="ghost"
          size="sm"
          onClick={() => handleContractSelect(row.original)}
        >
          <Check className="h-4 w-4" />
        </Button>
      ),
    },
  ]

  const table = useReactTable({
    data: contracts,
    columns,
    onSortingChange: setSorting,
    onColumnFiltersChange: setColumnFilters,
    onColumnVisibilityChange: setColumnVisibility,
    onRowSelectionChange: setRowSelection,
    onGlobalFilterChange: setGlobalFilter,
    getCoreRowModel: getCoreRowModel(),
    getPaginationRowModel: getPaginationRowModel(),
    getSortedRowModel: getSortedRowModel(),
    getFilteredRowModel: getFilteredRowModel(),
    state: {
      sorting,
      columnFilters,
      columnVisibility,
      rowSelection,
      globalFilter,
    },
  })

  const loadContracts = async () => {
    setLoading(true)
    try {
      const result = await getContracts()
      if (result.success) {
        setContracts(result.data)
        
        // preselectedContractId가 있으면 자동 선택
        if (preselectedContractId && !selectedContract) {
          const preselectedContract = result.data.find(c => c.id === preselectedContractId)
          if (preselectedContract) {
            onContractSelect(preselectedContract)
          }
        }
      } else {
        toast.error(result.error)
      }
    } catch (error) {
      toast.error('계약을 불러오는 중 오류가 발생했습니다.')
    } finally {
      setLoading(false)
    }
  }

  const handleContractSelect = (contract: Contract) => {
    onContractSelect(contract)
    setOpen(false)
  }

  useEffect(() => {
    if (open && contracts.length === 0) {
      loadContracts()
    }
  }, [open])

  // preselectedContractId가 변경되면 계약 목록 다시 로드
  useEffect(() => {
    if (preselectedContractId && contracts.length === 0) {
      loadContracts()
    }
  }, [preselectedContractId])

  return (
    <Dialog open={open} onOpenChange={setOpen}>
      <DialogTrigger asChild>
        <Button variant="outline" disabled={disabled} className="w-full justify-start">
          {selectedContract ? (
            <div className="flex items-center gap-2">
              <span className="font-mono text-sm">[{selectedContract.contractNo}]</span>
              <span className="truncate">{selectedContract.contractName}</span>
            </div>
          ) : (
            <span className="text-muted-foreground">계약을 선택하세요</span>
          )}
        </Button>
      </DialogTrigger>
      <DialogContent className="max-w-5xl max-h-[80vh]">
        <DialogHeader>
          <DialogTitle>계약 선택</DialogTitle>
        </DialogHeader>
        
        <div className="space-y-4">
          <div className="flex items-center space-x-2">
            <Search className="h-4 w-4" />
            <Input
              placeholder="계약번호, 계약명, 프로젝트 코드, 벤더명으로 검색..."
              value={globalFilter}
              onChange={(e) => setGlobalFilter(e.target.value)}
              className="flex-1"
            />
          </div>

          {loading ? (
            <div className="flex justify-center py-8">
              <div className="text-sm text-muted-foreground">계약을 불러오는 중...</div>
            </div>
          ) : (
            <div className="border rounded-md">
              <Table>
                <TableHeader>
                  {table.getHeaderGroups().map((headerGroup) => (
                    <TableRow key={headerGroup.id}>
                      {headerGroup.headers.map((header) => (
                        <TableHead key={header.id}>
                          {header.isPlaceholder
                            ? null
                            : flexRender(
                                header.column.columnDef.header,
                                header.getContext()
                              )}
                        </TableHead>
                      ))}
                    </TableRow>
                  ))}
                </TableHeader>
                <TableBody>
                  {table.getRowModel().rows?.length ? (
                    table.getRowModel().rows.map((row) => (
                      <TableRow
                        key={row.id}
                        data-state={row.getIsSelected() && "selected"}
                        className="cursor-pointer hover:bg-muted/50"
                        onClick={() => handleContractSelect(row.original)}
                      >
                        {row.getVisibleCells().map((cell) => (
                          <TableCell key={cell.id}>
                            {flexRender(
                              cell.column.columnDef.cell,
                              cell.getContext()
                            )}
                          </TableCell>
                        ))}
                      </TableRow>
                    ))
                  ) : (
                    <TableRow>
                      <TableCell
                        colSpan={columns.length}
                        className="h-24 text-center"
                      >
                        검색 결과가 없습니다.
                      </TableCell>
                    </TableRow>
                  )}
                </TableBody>
              </Table>
            </div>
          )}

          <div className="flex items-center justify-between">
            <div className="text-sm text-muted-foreground">
              총 {table.getFilteredRowModel().rows.length}개 계약
            </div>
            <div className="flex items-center space-x-2">
              <Button
                variant="outline"
                size="sm"
                onClick={() => table.previousPage()}
                disabled={!table.getCanPreviousPage()}
              >
                이전
              </Button>
              <div className="text-sm">
                {table.getState().pagination.pageIndex + 1} / {table.getPageCount()}
              </div>
              <Button
                variant="outline"
                size="sm"
                onClick={() => table.nextPage()}
                disabled={!table.getCanNextPage()}
              >
                다음
              </Button>
            </div>
          </div>
        </div>
      </DialogContent>
    </Dialog>
  )
}