// components/rfq/upload-response-dialog.tsx
"use client";

import { useState } from "react";
import { Button } from "@/components/ui/button";
import { Badge } from "@/components/ui/badge";
import {
  Dialog,
  DialogContent,
  DialogHeader,
  DialogTitle,
  DialogTrigger,
} from "@/components/ui/dialog";
import {
  Form,
  FormControl,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from "@/components/ui/form";
import { Input } from "@/components/ui/input";
import { Textarea } from "@/components/ui/textarea";
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import * as z from "zod";
import { Upload, FileText, X, Loader2 } from "lucide-react";
import { useToast } from "@/hooks/use-toast"
import { useRouter } from "next/navigation";

const uploadFormSchema = z.object({
  files: z.array(z.instanceof(File)).min(1, "최소 1개의 파일을 선택해주세요"),
  responseComment: z.string().optional(),
  vendorComment: z.string().optional(),
});

type UploadFormData = z.infer<typeof uploadFormSchema>;

interface UploadResponseDialogProps {
  responseId: number;
  attachmentType: string;
  serialNo: string;
  currentRevision: string;
  trigger?: React.ReactNode;
  onSuccess?: () => void;
}

export function UploadResponseDialog({
  responseId,
  attachmentType,
  serialNo,
  currentRevision,
  trigger,
  onSuccess,
}: UploadResponseDialogProps) {
  const [open, setOpen] = useState(false);
  const [isUploading, setIsUploading] = useState(false);
  const { toast } = useToast();
  const router = useRouter();

  const form = useForm<UploadFormData>({
    resolver: zodResolver(uploadFormSchema),
    defaultValues: {
      files: [],
      responseComment: "",
      vendorComment: "",
    },
  });

  const selectedFiles = form.watch("files");

  const handleFileSelect = (e: React.ChangeEvent<HTMLInputElement>) => {
    const files = Array.from(e.target.files || []);
    if (files.length > 0) {
      form.setValue("files", files);
    }
  };

  const removeFile = (index: number) => {
    const currentFiles = form.getValues("files");
    const newFiles = currentFiles.filter((_, i) => i !== index);
    form.setValue("files", newFiles);
  };

  const formatFileSize = (bytes: number): string => {
    if (bytes === 0) return "0 Bytes";
    const k = 1024;
    const sizes = ["Bytes", "KB", "MB", "GB"];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return parseFloat((bytes / Math.pow(k, i)).toFixed(2)) + " " + sizes[i];
  };

  const handleOpenChange = (newOpen: boolean) => {
    setOpen(newOpen);
    // 다이얼로그가 닫힐 때 form 리셋
    if (!newOpen) {
      form.reset();
    }
  };

  const handleCancel = () => {
    form.reset();
    setOpen(false);
  };

  const onSubmit = async (data: UploadFormData) => {
    setIsUploading(true);
    
    try {
      // 1. 각 파일을 업로드 API로 전송
      const uploadedFiles = [];
      
      for (const file of data.files) {
        const formData = new FormData();
        formData.append("file", file);
        formData.append("responseId", responseId.toString());
        formData.append("description", ""); // 필요시 파일별 설명 추가 가능
        
        const uploadResponse = await fetch("/api/vendor-responses/upload", {
          method: "POST",
          body: formData,
        });
        
        if (!uploadResponse.ok) {
          const error = await uploadResponse.json();
          throw new Error(error.message || "파일 업로드 실패");
        }
        
        const uploadResult = await uploadResponse.json();
        uploadedFiles.push(uploadResult);
      }
      
      // 2. vendor response 상태 업데이트 (서버에서 자동으로 리비전 증가)
      const updateResponse = await fetch("/api/vendor-responses/update", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          responseId,
          responseStatus: "RESPONDED",
          // respondedRevision 제거 - 서버에서 자동 처리
          responseComment: data.responseComment,
          vendorComment: data.vendorComment,
          respondedAt: new Date().toISOString(),
        }),
      });
      
      if (!updateResponse.ok) {
        const error = await updateResponse.json();
        throw new Error(error.message || "응답 상태 업데이트 실패");
      }

      const updateResult = await updateResponse.json();
      
      toast({
        title: "업로드 완료",
        description: `${data.files.length}개 파일이 성공적으로 업로드되었습니다. (${updateResult.newRevision})`,
      });
      
      setOpen(false);
      form.reset();

      router.refresh();
      onSuccess?.();
      
    } catch (error) {
      console.error("Upload error:", error);
      toast({
        title: "업로드 실패",
        description: error instanceof Error ? error.message : "알 수 없는 오류가 발생했습니다.",
        variant: "destructive",
      });
    } finally {
      setIsUploading(false);
    }
  };

  return (
    <Dialog open={open} onOpenChange={handleOpenChange}>
      <DialogTrigger asChild>
        {trigger || (
          <Button size="sm">
            <Upload className="h-3 w-3 mr-1" />
            업로드
          </Button>
        )}
      </DialogTrigger>
      <DialogContent className="max-w-2xl max-h-[80vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle className="flex items-center gap-2">
            <Upload className="h-5 w-5" />
            응답 파일 업로드
          </DialogTitle>
          <div className="flex items-center gap-2 text-sm text-muted-foreground">
            <Badge variant="outline">{serialNo}</Badge>
            <span>{attachmentType}</span>
            <Badge variant="secondary">{currentRevision}</Badge>
            <span className="text-xs text-blue-600">→ 벤더 응답 리비전 자동 증가</span>
          </div>
        </DialogHeader>

        <Form {...form}>
          <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
            {/* 파일 선택 */}
            <FormField
              control={form.control}
              name="files"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>파일 선택</FormLabel>
                  <FormControl>
                    <div className="space-y-4">
                      <Input
                        type="file"
                        multiple
                        onChange={handleFileSelect}
                        accept=".pdf,.doc,.docx,.xls,.xlsx,.png,.jpg,.jpeg,.zip,.rar"
                        className="cursor-pointer"
                      />
                      <div className="text-xs text-muted-foreground">
                        지원 파일: PDF, DOC, DOCX, XLS, XLSX, PNG, JPG, ZIP, RAR (최대 10MB)
                      </div>
                    </div>
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />

            {/* 선택된 파일 목록 */}
            {selectedFiles.length > 0 && (
              <div className="space-y-2">
                <div className="text-sm font-medium">선택된 파일 ({selectedFiles.length}개)</div>
                <div className="space-y-2 max-h-40 overflow-y-auto">
                  {selectedFiles.map((file, index) => (
                    <div
                      key={index}
                      className="flex items-center justify-between p-3 bg-muted/50 rounded-lg"
                    >
                      <div className="flex items-center gap-2 flex-1 min-w-0">
                        <FileText className="h-4 w-4 text-muted-foreground flex-shrink-0" />
                        <div className="min-w-0 flex-1">
                          <div className="text-sm font-medium truncate">{file.name}</div>
                          <div className="text-xs text-muted-foreground">
                            {formatFileSize(file.size)}
                          </div>
                        </div>
                      </div>
                      <Button
                        type="button"
                        variant="ghost"
                        size="sm"
                        onClick={() => removeFile(index)}
                        className="flex-shrink-0 ml-2"
                      >
                        <X className="h-4 w-4" />
                      </Button>
                    </div>
                  ))}
                </div>
              </div>
            )}

            {/* 응답 코멘트 */}
            <FormField
              control={form.control}
              name="responseComment"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>응답 코멘트</FormLabel>
                  <FormControl>
                    <Textarea
                      placeholder="응답에 대한 설명을 입력하세요..."
                      className="resize-none"
                      rows={3}
                      {...field}
                    />
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />

            {/* 벤더 코멘트 */}
            <FormField
              control={form.control}
              name="vendorComment"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>벤더 코멘트 (내부용)</FormLabel>
                  <FormControl>
                    <Textarea
                      placeholder="내부 참고용 코멘트를 입력하세요..."
                      className="resize-none"
                      rows={2}
                      {...field}
                    />
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />

            {/* 버튼 */}
            <div className="flex justify-end gap-2">
              <Button
                type="button"
                variant="outline"
                onClick={handleCancel}
                disabled={isUploading}
              >
                취소
              </Button>
              <Button type="submit" disabled={isUploading || selectedFiles.length === 0}>
                {isUploading && <Loader2 className="h-4 w-4 mr-2 animate-spin" />}
                {isUploading ? "업로드 중..." : "업로드"}
              </Button>
            </div>
          </form>
        </Form>
      </DialogContent>
    </Dialog>
  );
}