import React, { useState, useEffect } from 'react';
import { useQuery } from '@tanstack/react-query';
import { Button } from '@/client/components/ui/button';
import { Dialog, DialogContent, DialogDescription, DialogFooter, DialogHeader, DialogTitle } from '@/client/components/ui/dialog';
import { Card, CardContent } from '@/client/components/ui/card';
import { toast } from 'sonner';
import { fileClient } from '@/client/api';
import MinioUploader from '@/client/admin/components/MinioUploader';
import { Check, Upload, Eye, X, File as FileIcon, Image as ImageIcon } from 'lucide-react';
import { cn } from '@/client/lib/utils';
import type { InferResponseType } from 'hono/client';

type FileType = InferResponseType<typeof fileClient.$get, 200>['data'][0]

export interface FileSelectorProps {
  value?: number | null | number[];
  onChange?: (fileId: number | null | number[]) => void;
  accept?: string;
  maxSize?: number;
  uploadPath?: string;
  previewSize?: 'small' | 'medium' | 'large';
  showPreview?: boolean;
  placeholder?: string;
  title?: string;
  description?: string;
  filterType?: 'image' | 'all' | string;
  allowMultiple?: boolean;
}

export const FileSelector: React.FC<FileSelectorProps> = ({
  value,
  onChange,
  accept = '*/*',
  maxSize = 10,
  uploadPath = '/files',
  previewSize = 'medium',
  showPreview = true,
  placeholder = '选择文件',
  title = '选择文件',
  description = '上传新文件或从已有文件中选择',
  filterType = 'all',
  allowMultiple = false,
}) => {
  const [isOpen, setIsOpen] = useState(false);
  const [selectedFile, setSelectedFile] = useState<FileType | null>(null);
  const [localSelectedFiles, setLocalSelectedFiles] = useState<number[]>([]);

  // 获取当前选中的文件详情 - 支持单值和数组
  const { data: currentFiles } = useQuery<FileType[]>({
    queryKey: ['file-details', value, allowMultiple],
    queryFn: async (): Promise<FileType[]> => {
      if (!value) return [];
      
      // 处理多选模式下的数组值
      if (allowMultiple && Array.isArray(value)) {
        if (value.length === 0) return [];
        
        // 批量获取多个文件详情
        const filePromises = value.map(async (fileId) => {
          try {
            const response = await fileClient[':id']['$get']({ param: { id: Number(fileId) } });
            if (response.status === 200) {
              return response.json();
            }
            return null;
          } catch (error) {
            console.error(`获取文件 ${fileId} 详情失败:`, error);
            return null;
          }
        });
        
        const files = await Promise.all(filePromises);
        return files.filter(file => file !== null);
      }
      
      // 处理单选模式下的单值
      if (!Array.isArray(value)) {
        const response = await fileClient[':id']['$get']({ param: { id: Number(value) } });
        if (response.status !== 200) throw new Error('获取文件详情失败');
        return [await response.json()];
      }
      
      return [];
    },
    enabled: !!value,
  });

  // 当对话框打开时，设置当前选中的文件
  useEffect(() => {
    if (isOpen) {
      if (allowMultiple) {
        // 在多选模式下，使用 value 数组初始化本地选择
        const initialSelection = Array.isArray(value) ? value : [];
        setLocalSelectedFiles(initialSelection);
      } else if (value && currentFiles && currentFiles.length > 0) {
        setSelectedFile(currentFiles[0]);
      }
    }
  }, [isOpen, value, currentFiles, allowMultiple]);

  // 获取文件列表
  const { data: filesData, isLoading, refetch } = useQuery({
    queryKey: ['files-for-selection', filterType] as const,
    queryFn: async () => {
      const response = await fileClient.$get({
        query: {
          page: 1,
          pageSize: 50,
          ...(filterType !== 'all' && { keyword: filterType })
        }
      });
      if (response.status !== 200) throw new Error('获取文件列表失败');
      return response.json();
    },
    enabled: isOpen,
  });

  const files = filesData?.data?.filter((f) => {
    if (filterType === 'all') return true;
    if (filterType === 'image') return f?.type?.startsWith('image/');
    return f?.type?.includes(filterType);
  }) || [];

  const handleSelectFile = (file: FileType) => {
    if (allowMultiple) {
      setLocalSelectedFiles(prev => {
        const newSelection = prev.includes(file.id)
          ? prev.filter(id => id !== file.id)
          : [...prev, file.id];
        return newSelection;
      });
    } else {
      setSelectedFile(prevSelected => {
        if (prevSelected?.id === file.id) {
          return null;
        }
        return file;
      });
    }
  };

  const handleConfirm = () => {
    if (allowMultiple) {
      if (onChange) {
        onChange(localSelectedFiles);
      }
      setIsOpen(false);
      return;
    }

    if (!selectedFile) {
      toast.warning('请选择一个文件');
      return;
    }
    if (onChange) {
      onChange(selectedFile.id);
    }
    setIsOpen(false);
    setSelectedFile(null);
  };

  const handleCancel = () => {
    setIsOpen(false);
    setSelectedFile(null);
    // 取消时重置为初始的 value 值
    const initialSelection = allowMultiple && Array.isArray(value) ? value : [];
    setLocalSelectedFiles(initialSelection);
  };

  const handleUploadSuccess = () => {
    toast.success('文件上传成功！请从列表中选择新上传的文件');
    refetch();
  };

  const getPreviewSize = () => {
    switch (previewSize) {
      case 'small':
        return 'h-16 w-16';
      case 'medium':
        return 'h-24 w-24';
      case 'large':
        return 'h-32 w-32';
      default:
        return 'h-24 w-24';
    }
  };

  const getFileIcon = (fileType: string) => {
    if (fileType.startsWith('image/')) {
      return <ImageIcon className="h-8 w-8 text-gray-400" />;
    }
    if (fileType.startsWith('video/')) {
      return <FileIcon className="h-8 w-8 text-blue-500" />;
    }
    if (fileType.startsWith('audio/')) {
      return <FileIcon className="h-8 w-8 text-green-500" />;
    }
    if (fileType.includes('pdf')) {
      return <FileIcon className="h-8 w-8 text-red-500" />;
    }
    if (fileType.includes('text')) {
      return <FileIcon className="h-8 w-8 text-gray-600" />;
    }
    return <FileIcon className="h-8 w-8 text-gray-400" />;
  };

  const handleRemoveFile = (e: React.MouseEvent) => {
    e.stopPropagation();
    if (allowMultiple && Array.isArray(value)) {
      // 在多选模式下，移除所有选中文件
      onChange?.([]);
    } else {
      // 在单选模式下，设置为null
      onChange?.(null);
    }
  };

  const isSelected = (fileId: number) => {
    if (allowMultiple) {
      return localSelectedFiles.includes(fileId);
    }
    return selectedFile?.id === fileId;
  };

  return (
    <>
      <div className="space-y-4">
        {showPreview && (
          <div className="flex items-start space-x-4">
            {/* 预览区域 */}
            <div className="flex flex-wrap gap-2">
              {allowMultiple && Array.isArray(currentFiles) && currentFiles.length > 0 ? (
                // 多选模式下的预览
                currentFiles.map((file) => (
                  <div key={file.id} className="relative group">
                    <div
                      className={cn(
                        getPreviewSize(),
                        "border-2 border-dashed cursor-pointer hover:border-primary transition-colors rounded-lg overflow-hidden flex items-center justify-center bg-gray-100"
                      )}
                      onClick={() => setIsOpen(true)}
                    >
                      {file?.type ? (
                        <div className="w-full h-full flex items-center justify-center">
                          {file.type.startsWith('image/') ? (
                            <img
                              src={file.fullUrl}
                              alt={file.name}
                              className="w-full h-full object-cover"
                            />
                          ) : (
                            <div className="flex flex-col items-center justify-center text-gray-400">
                              {getFileIcon(file.type)}
                              <span className="text-xs mt-1 text-center px-1 truncate max-w-full">
                                {file.name}
                              </span>
                            </div>
                          )}
                        </div>
                      ) : (
                        <div className="flex flex-col items-center justify-center text-gray-400">
                          <FileIcon className="h-8 w-8 mb-1" />
                          <span className="text-xs">{placeholder}</span>
                        </div>
                      )}
                    </div>
                    
                    <button
                      type="button"
                      className="absolute -top-2 -right-2 bg-red-500 text-white rounded-full p-1 opacity-0 group-hover:opacity-100 transition-opacity"
                      onClick={(e) => {
                        e.stopPropagation();
                        if (allowMultiple && Array.isArray(value)) {
                          const newValue = value.filter(id => id !== file.id);
                          onChange?.(newValue);
                        }
                      }}
                    >
                      <X className="h-3 w-3" />
                    </button>
                  </div>
                ))
              ) : !allowMultiple && currentFiles && currentFiles.length > 0 ? (
                // 单选模式下的预览
                <div className="relative group">
                  <div
                    className={cn(
                      getPreviewSize(),
                      "border-2 border-dashed cursor-pointer hover:border-primary transition-colors rounded-lg overflow-hidden flex items-center justify-center bg-gray-100"
                    )}
                    onClick={() => setIsOpen(true)}
                  >
                    {currentFiles[0]?.type ? (
                      <div className="w-full h-full flex items-center justify-center">
                        {currentFiles[0].type.startsWith('image/') ? (
                          <img
                            src={currentFiles[0].fullUrl}
                            alt={currentFiles[0].name}
                            className="w-full h-full object-cover"
                          />
                        ) : (
                          <div className="flex flex-col items-center justify-center text-gray-400">
                            {getFileIcon(currentFiles[0].type)}
                            <span className="text-xs mt-1 text-center">{currentFiles[0].name}</span>
                          </div>
                        )}
                      </div>
                    ) : (
                      <div className="flex flex-col items-center justify-center text-gray-400">
                        <FileIcon className="h-8 w-8 mb-1" />
                        <span className="text-xs">{placeholder}</span>
                      </div>
                    )}
                  </div>
                  
                  {currentFiles[0] && (
                    <button
                      type="button"
                      className="absolute -top-2 -right-2 bg-red-500 text-white rounded-full p-1 opacity-0 group-hover:opacity-100 transition-opacity"
                      onClick={handleRemoveFile}
                    >
                      <X className="h-3 w-3" />
                    </button>
                  )}
                </div>
              ) : (
                // 没有选中文件时的占位符
                <div
                  className={cn(
                    getPreviewSize(),
                    "border-2 border-dashed cursor-pointer hover:border-primary transition-colors rounded-lg overflow-hidden flex items-center justify-center bg-gray-100"
                  )}
                  onClick={() => setIsOpen(true)}
                >
                  <div className="flex flex-col items-center justify-center text-gray-400">
                    <FileIcon className="h-8 w-8 mb-1" />
                    <span className="text-xs">{placeholder}</span>
                  </div>
                </div>
              )}
            </div>
            
            <div className="space-y-2">
              <Button
                type="button"
                variant="outline"
                onClick={() => setIsOpen(true)}
                className="text-sm"
              >
                {((allowMultiple && currentFiles && currentFiles.length > 0) ||
                  (!allowMultiple && currentFiles && currentFiles.length > 0)) ? '更换文件' : placeholder}
              </Button>
              {!allowMultiple && currentFiles && currentFiles.length > 0 && (
                <p className="text-xs text-muted-foreground truncate w-40 sm:w-64">
                  当前: {currentFiles[0].name}
                </p>
              )}
              {allowMultiple && currentFiles && currentFiles.length > 0 && (
                <p className="text-xs text-muted-foreground">
                  已选择 {currentFiles.length} 个文件
                </p>
              )}
            </div>
          </div>
        )}

        {!showPreview && (
          <Button 
            type="button" 
            variant="outline" 
            onClick={() => setIsOpen(true)}
            className="w-full"
          >
            {currentFiles ? '更换文件' : placeholder}
          </Button>
        )}
      </div>

      <Dialog open={isOpen} onOpenChange={setIsOpen}>
        <DialogContent className="max-w-4xl max-h-[90vh]">
          <DialogHeader>
            <DialogTitle>{title}</DialogTitle>
            <DialogDescription>
              {description}
            </DialogDescription>
          </DialogHeader>

          <div className="space-y-4">
            {/* 文件列表 */}
            <div className="space-y-2 max-h-96 overflow-y-auto p-1">
              {isLoading ? (
                <Card>
                  <CardContent className="text-center py-8">
                    <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-primary mx-auto"></div>
                    <p className="text-gray-500 mt-2">加载中...</p>
                  </CardContent>
                </Card>
              ) : (
                <div className="grid grid-cols-3 sm:grid-cols-4 md:grid-cols-5 gap-3">
                  {/* 上传区域 - 作为第一项 */}
                  <div className="relative cursor-pointer transition-all duration-200">
                    <div className="rounded-lg border-2 border-dashed border-gray-300 hover:border-primary transition-colors hover:scale-105">
                      <div className="p-2 h-20 flex items-center justify-center">
                        <MinioUploader
                          uploadPath={uploadPath}
                          accept={accept}
                          maxSize={maxSize}
                          onUploadSuccess={handleUploadSuccess}
                          buttonText="上传"
                          size="minimal"
                          displayMode="card"
                          showUploadList={false}
                        />
                      </div>
                    </div>
                    <p className="text-xs text-center mt-1 text-muted-foreground">
                      上传新文件
                    </p>
                  </div>

                  {/* 现有文件列表 */}
                  {files.map((file) => (
                    <div
                      key={file.id}
                      className={cn(
                        "relative cursor-pointer transition-all duration-200",
                        "hover:scale-105"
                      )}
                      onClick={() => handleSelectFile(file)}
                    >
                      <div
                        className={cn(
                          "relative rounded-lg overflow-hidden border-2 aspect-square",
                          isSelected(file.id)
                            ? "border-primary ring-2 ring-primary ring-offset-2"
                            : "border-gray-200 hover:border-primary"
                        )}
                      >
                        {file?.type?.startsWith('image/') ? (
                          <img
                            src={file.fullUrl}
                            alt={file.name}
                            className="w-full h-full object-cover"
                          />
                        ) : (
                          <div className="w-full h-full flex flex-col items-center justify-center bg-gray-50 p-2">
                            {file.type && getFileIcon(file.type)}
                            <p className="text-xs text-center mt-1 truncate max-w-full">
                              {file.name}
                            </p>
                          </div>
                        )}
                        
                        {isSelected(file.id) && (
                          <div className="absolute inset-0 bg-primary/20 flex items-center justify-center">
                            <Check className="h-6 w-6 text-white bg-primary rounded-full p-1" />
                          </div>
                        )}
                        
                        <div className="absolute top-1 right-1">
                          <Eye
                            className="h-4 w-4 text-white bg-black/50 rounded-full p-0.5 cursor-pointer hover:bg-black/70"
                            onClick={(e) => {
                              e.stopPropagation();
                              window.open(file.fullUrl, '_blank');
                            }}
                          />
                        </div>
                      </div>
                      
                      <p className="text-xs text-center mt-1 truncate">
                        {file.name}
                      </p>
                    </div>
                  ))}
                  
                  {/* 空状态 - 当没有文件时显示 */}
                  {files.length === 0 && (
                    <div className="col-span-full">
                      <Card>
                        <CardContent className="text-center py-8">
                          <div className="flex flex-col items-center">
                            <Upload className="h-12 w-12 text-gray-400 mb-4" />
                            <p className="text-gray-600">暂无文件</p>
                            <p className="text-sm text-gray-500 mt-2">请上传文件</p>
                          </div>
                        </CardContent>
                      </Card>
                    </div>
                  )}
                </div>
              )}
            </div>
          </div>

          <DialogFooter>
            <Button type="button" variant="outline" onClick={handleCancel}>
              取消
            </Button>
            <Button
              type="button"
              onClick={handleConfirm}
              disabled={allowMultiple ? localSelectedFiles.length === 0 : !selectedFile}
            >
              {allowMultiple ? `确认选择 (${localSelectedFiles.length})` : '确认选择'}
            </Button>
          </DialogFooter>
        </DialogContent>
      </Dialog>
    </>
  );
};

export default FileSelector;