'use client';

import * as React from 'react';
import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
import {
  ChevronLeft,
  ChevronRight,
  Download,
  FileArchive,
  FileAudio,
  FileImage,
  FileText,
  FileVideo,
  Globe,
  Loader2,
  Lock,
  Plus,
  Search,
  Trash2,
  Upload,
} from 'lucide-react';
import { toast } from 'sonner';

import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Badge } from '@/components/ui/badge';
import { Card, CardContent } from '@/components/ui/card';
import {
  AlertDialog,
  AlertDialogAction,
  AlertDialogCancel,
  AlertDialogContent,
  AlertDialogDescription,
  AlertDialogFooter,
  AlertDialogHeader,
  AlertDialogTitle,
} from '@/components/ui/alert-dialog';

import { FileImagePreview } from '@/components/common/file-image-preview';
import services, { formatFileSize } from '@/lib/services';
import type { Upload as UploadRecord } from '@/lib/services/upload/types';

/* ─── 工具函数 ─────────────────────────────────────────── */

function getFileIcon(mimeType: string, className = 'size-10') {
  if (mimeType.startsWith('image/'))
    return <FileImage className={`${className} text-blue-400`} />;
  if (mimeType.startsWith('video/'))
    return <FileVideo className={`${className} text-purple-400`} />;
  if (mimeType.startsWith('audio/'))
    return <FileAudio className={`${className} text-green-400`} />;
  if (
    mimeType.includes('zip') ||
    mimeType.includes('tar') ||
    mimeType.includes('gzip')
  )
    return <FileArchive className={`${className} text-amber-400`} />;
  return <FileText className={`${className} text-slate-400`} />;
}

function formatDate(dateStr: string) {
  return new Date(dateStr).toLocaleString('zh-CN', {
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit',
  });
}

export function UserFileManager() {
  const queryClient = useQueryClient();
  const [keyword, setKeyword] = React.useState('');
  const [debouncedKeyword, setDebouncedKeyword] = React.useState('');
  const [page, setPage] = React.useState(1);
  const [uploading, setUploading] = React.useState(false);
  const [deleteTarget, setDeleteTarget] = React.useState<UploadRecord | null>(
    null,
  );
  const [uploadAccessMode, setUploadAccessMode] = React.useState<number>(0); // 默认私有
  const fileInputRef = React.useRef<HTMLInputElement>(null);
  const pageSize = 12; // 每页 12 个卡片更均衡（3x4 或 4x3 布局）

  // 搜索防抖
  React.useEffect(() => {
    const timer = setTimeout(() => {
      setDebouncedKeyword(keyword);
      setPage(1);
    }, 400);
    return () => clearTimeout(timer);
  }, [keyword]);

  // 我的文件列表查询
  const { data, isPending } = useQuery({
    queryKey: ['user-files', page, pageSize, debouncedKeyword],
    queryFn: () =>
      services.upload.listMyUploads(
        page,
        pageSize,
        debouncedKeyword || undefined,
      ),
  });

  const files = data?.items ?? [];
  const total = data?.total ?? 0;
  const totalPages = Math.ceil(total / pageSize);

  // 上传文件 Mutation
  const uploadMutation = useMutation({
    mutationFn: async (file: File) => {
      return services.upload.uploadFile(
        file,
        'generic',
        undefined,
        uploadAccessMode,
      );
    },
    onMutate: () => {
      setUploading(true);
    },
    onSuccess: () => {
      toast.success('文件上传成功');
      void queryClient.invalidateQueries({ queryKey: ['user-files'] });
    },
    onError: (err: Error) => {
      toast.error(err.message || '上传失败');
    },
    onSettled: () => {
      setUploading(false);
      if (fileInputRef.current) {
        fileInputRef.current.value = '';
      }
    },
  });

  // 删除文件 Mutation
  const deleteMutation = useMutation({
    mutationFn: (id: string) => services.upload.deleteMyFile(id),
    onSuccess: () => {
      toast.success('文件已成功删除');
      void queryClient.invalidateQueries({ queryKey: ['user-files'] });
      setDeleteTarget(null);
    },
    onError: (err: Error) => {
      toast.error(err.message || '删除失败');
    },
  });

  const handleFileChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0];
    if (file) {
      uploadMutation.mutate(file);
    }
  };

  const triggerUploadClick = () => {
    fileInputRef.current?.click();
  };

  const handleDownload = (file: UploadRecord) => {
    const url = services.upload.getDownloadUrl(file.id);
    const a = document.createElement('a');
    a.href = url;
    a.download = file.file_name;
    a.click();
  };

  return (
    <div className='flex w-full flex-col gap-6'>
      {/* 操作栏：搜索、权限选择、上传按钮 */}
      <div className='flex flex-col sm:flex-row items-stretch sm:items-center justify-between gap-4'>
        <div className='relative flex-1 max-w-md'>
          <Search className='absolute left-3 top-1/2 -translate-y-1/2 size-4 text-muted-foreground' />
          <Input
            placeholder='搜索文件名...'
            value={keyword}
            onChange={(e) => setKeyword(e.target.value)}
            className='pl-9 h-9'
          />
        </div>

        <div className='flex items-center gap-3 self-end sm:self-auto'>
          {/* 上传权限设置 */}
          <div className='flex items-center gap-1.5 border rounded-lg p-1 bg-muted/40 h-9 text-xs'>
            <Button
              variant={uploadAccessMode === 0 ? 'secondary' : 'ghost'}
              size='sm'
              className='h-7 px-2.5 text-xs font-normal'
              onClick={() => setUploadAccessMode(0)}
            >
              <Lock className='mr-1 size-3 text-amber-500' />
              私有
            </Button>
            <Button
              variant={uploadAccessMode === 1 ? 'secondary' : 'ghost'}
              size='sm'
              className='h-7 px-2.5 text-xs font-normal'
              onClick={() => setUploadAccessMode(1)}
            >
              <Globe className='mr-1 size-3 text-sky-500' />
              公开
            </Button>
          </div>

          <input
            type='file'
            ref={fileInputRef}
            onChange={handleFileChange}
            className='hidden'
            disabled={uploading}
          />
          <Button
            onClick={triggerUploadClick}
            disabled={uploading}
            className='h-9 gap-1.5 text-xs font-medium'
          >
            {uploading ? (
              <Loader2 className='size-3.5 animate-spin' />
            ) : (
              <Plus className='size-3.5' />
            )}
            {uploading ? '正在上传...' : '上传文件'}
          </Button>
        </div>
      </div>

      {/* 文件展示区 */}
      {isPending ? (
        <div className='flex items-center justify-center py-24'>
          <Loader2 className='size-8 animate-spin text-primary' />
        </div>
      ) : files.length === 0 ? (
        <Card className='border border-dashed py-16 flex flex-col items-center justify-center text-center'>
          <CardContent className='flex flex-col items-center gap-4'>
            <div className='p-4 bg-muted rounded-full text-muted-foreground/60'>
              <Upload className='size-10' />
            </div>
            <div className='space-y-1'>
              <h3 className='font-semibold text-sm'>还没有上传文件</h3>
              <p className='text-xs text-muted-foreground max-w-xs'>
                {debouncedKeyword
                  ? '未搜索到匹配的文件'
                  : '上传您的第一个文件，支持图片、视频、文档和压缩包等格式。'}
              </p>
            </div>
            {!debouncedKeyword && (
              <Button
                onClick={triggerUploadClick}
                disabled={uploading}
                size='sm'
                className='mt-2 text-xs'
              >
                选择文件上传
              </Button>
            )}
          </CardContent>
        </Card>
      ) : (
        <div className='grid grid-cols-1 sm:grid-cols-2 md:grid-cols-3 lg:grid-cols-4 gap-4'>
          {files.map((file) => (
            <Card
              key={file.id}
              className='group border border-border/40 hover:border-border/80 bg-card/60 hover:bg-card/95 transition-all duration-300 shadow-xs hover:shadow-md overflow-hidden relative flex flex-col h-full'
            >
              {/* 文件预览/图标区 */}
              <div className='h-36 bg-muted/30 border-b border-dashed relative flex items-center justify-center overflow-hidden p-2 group-hover:bg-muted/10 transition-colors'>
                {file.mime_type.startsWith('image/') ? (
                  <FileImagePreview
                    fileId={file.id}
                    alt={file.file_name}
                    quality='medium'
                    className='max-h-full max-w-full object-contain rounded-md shadow-xs transition-transform duration-350 group-hover:scale-103'
                    fallbackClassName='min-h-full w-full rounded-md'
                  />
                ) : (
                  getFileIcon(file.mime_type)
                )}

                {/* 访问权限 Badge */}
                <div className='absolute top-2 right-2'>
                  {file.access_mode === 0 ? (
                    <Badge
                      variant='secondary'
                      className='bg-amber-500/10 text-amber-600 dark:text-amber-400 text-[10px] gap-1 px-1.5 py-0 rounded-md border border-amber-500/20 font-normal'
                    >
                      <Lock className='size-2.5' />
                      私有
                    </Badge>
                  ) : (
                    <Badge
                      variant='secondary'
                      className='bg-sky-500/10 text-sky-600 dark:text-sky-400 text-[10px] gap-1 px-1.5 py-0 rounded-md border border-sky-500/20 font-normal'
                    >
                      <Globe className='size-2.5' />
                      公开
                    </Badge>
                  )}
                </div>
              </div>

              {/* 文件详情区 */}
              <CardContent className='p-4 flex-1 flex flex-col justify-between gap-3'>
                <div className='space-y-1'>
                  <h4
                    className='font-semibold text-xs text-foreground truncate select-all'
                    title={file.file_name}
                  >
                    {file.file_name}
                  </h4>
                  <div className='flex items-center justify-between text-[10px] text-muted-foreground font-mono'>
                    <span>{formatFileSize(file.file_size)}</span>
                    <span
                      className='truncate max-w-[120px]'
                      title={file.mime_type}
                    >
                      {file.mime_type}
                    </span>
                  </div>
                </div>

                <div className='flex items-center justify-between pt-1 border-t border-dashed'>
                  <span className='text-[9px] text-muted-foreground/80'>
                    {formatDate(file.created_at)}
                  </span>

                  <div className='flex items-center gap-1'>
                    <Button
                      size='icon'
                      variant='ghost'
                      className='size-7 rounded-md hover:bg-muted text-muted-foreground hover:text-foreground'
                      title='下载文件'
                      onClick={() => handleDownload(file)}
                    >
                      <Download className='size-3.5' />
                    </Button>
                    <Button
                      size='icon'
                      variant='ghost'
                      className='size-7 rounded-md hover:bg-destructive/10 text-muted-foreground hover:text-destructive'
                      title='删除文件'
                      onClick={() => setDeleteTarget(file)}
                    >
                      <Trash2 className='size-3.5' />
                    </Button>
                  </div>
                </div>
              </CardContent>
            </Card>
          ))}
        </div>
      )}

      {/* 分页 */}
      {totalPages > 1 && (
        <div className='flex items-center justify-center gap-2 pt-4'>
          <Button
            size='sm'
            variant='outline'
            className='border-dashed text-xs h-8 px-3'
            disabled={page <= 1}
            onClick={() => setPage((p) => p - 1)}
          >
            <ChevronLeft className='mr-1 size-3.5' />
            上一页
          </Button>
          <span className='text-xs text-muted-foreground font-medium px-2'>
            {page} / {totalPages}
          </span>
          <Button
            size='sm'
            variant='outline'
            className='border-dashed text-xs h-8 px-3'
            disabled={page >= totalPages}
            onClick={() => setPage((p) => p + 1)}
          >
            下一页
            <ChevronRight className='ml-1 size-3.5' />
          </Button>
        </div>
      )}

      {/* 删除确认 Dialog */}
      <AlertDialog
        open={!!deleteTarget}
        onOpenChange={(open) => !open && setDeleteTarget(null)}
      >
        <AlertDialogContent suppressHydrationWarning>
          <AlertDialogHeader>
            <AlertDialogTitle>确认删除文件</AlertDialogTitle>
            <AlertDialogDescription>
              确定要删除文件{' '}
              <span className='font-semibold text-foreground'>
                「{deleteTarget?.file_name}」
              </span>{' '}
              吗？删除后此文件将无法恢复。
            </AlertDialogDescription>
          </AlertDialogHeader>
          <AlertDialogFooter>
            <AlertDialogCancel disabled={deleteMutation.isPending}>
              取消
            </AlertDialogCancel>
            <AlertDialogAction
              onClick={() =>
                deleteTarget && deleteMutation.mutate(deleteTarget.id)
              }
              disabled={deleteMutation.isPending}
              className='bg-destructive hover:bg-destructive/90 text-destructive-foreground'
            >
              {deleteMutation.isPending && (
                <Loader2 className='mr-1.5 size-3.5 animate-spin' />
              )}
              确认删除
            </AlertDialogAction>
          </AlertDialogFooter>
        </AlertDialogContent>
      </AlertDialog>
    </div>
  );
}