import { useParams, useNavigate, Link } from 'react-router-dom';
import { useDocument, useDocumentAnalysis, useAnalyzeDocument } from '@/hooks/useDocuments';
import { Button } from '@/components/Button';
import { Card } from '@/components/Card';
import { ArrowLeft, FileText, Sparkles, Tag, FolderOpen, Trash2, Edit2, CheckSquare } from 'lucide-react';
import { useState, useEffect } from 'react';

export default function DocumentDetailPage() {
  const { id } = useParams<{ id: string }>();
  const navigate = useNavigate();
  const { data: document, isLoading: docLoading, error: docError } = useDocument(id || '');
  const { data: analysis, isLoading: analysisLoading } = useDocumentAnalysis(id || '');
  const analyzeMutation = useAnalyzeDocument();
  const [isEditing, setIsEditing] = useState(false);
  const [editedTitle, setEditedTitle] = useState('');
  const [editedContent, setEditedContent] = useState('');

  useEffect(() => {
    if (document) {
      setEditedTitle(document.title || '');
      setEditedContent(document.content);
    }
  }, [document]);

  const handleAnalyze = async () => {
    if (!id) return;
    try {
      await analyzeMutation.mutateAsync({ id });
    } catch (err: any) {
      alert(err.message || 'AI 分析失败');
    }
  };

  const handleSave = () => {
    // TODO: 实现保存功能
    setIsEditing(false);
  };

  if (docLoading) {
    return (
      <div className="flex items-center justify-center min-h-screen">
        <div className="text-gray-600">加载中...</div>
      </div>
    );
  }

  if (docError || !document) {
    return (
      <div className="flex items-center justify-center min-h-screen">
        <Card variant="bordered" className="max-w-md">
          <div className="text-center py-8">
            <p className="text-red-600 mb-4">文档不存在或无权访问</p>
            <Link to="/documents">
              <Button>返回文档列表</Button>
            </Link>
          </div>
        </Card>
      </div>
    );
  }

  return (
    <div className="max-w-4xl mx-auto space-y-6">
      {/* 头部导航 */}
      <div className="flex items-center gap-4">
        <Link to="/documents">
          <button className="p-2 hover:bg-gray-100 rounded-lg">
            <ArrowLeft className="h-5 w-5 text-gray-600" />
          </button>
        </Link>
        <div className="flex-1">
          <h1 className="text-2xl font-bold text-gray-900">文档详情</h1>
        </div>
      </div>

      {/* 文档内容卡片 */}
      <Card variant="bordered">
        <div className="space-y-4">
          {/* 标题和操作栏 */}
          <div className="flex items-start justify-between">
            {isEditing ? (
              <input
                type="text"
                value={editedTitle}
                onChange={(e) => setEditedTitle(e.target.value)}
                className="flex-1 mr-4 px-3 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500"
                placeholder="文档标题"
              />
            ) : (
              <h2 className="flex-1 text-xl font-semibold text-gray-900">
                {document.title || '无标题'}
              </h2>
            )}
            <div className="flex gap-2">
              {isEditing ? (
                <>
                  <Button size="sm" onClick={handleSave}>
                    保存
                  </Button>
                  <Button size="sm" variant="secondary" onClick={() => setIsEditing(false)}>
                    取消
                  </Button>
                </>
              ) : (
                <>
                  <button
                    onClick={() => setIsEditing(true)}
                    className="p-2 hover:bg-gray-100 rounded-lg"
                    title="编辑"
                  >
                    <Edit2 className="h-4 w-4 text-gray-600" />
                  </button>
                  <button
                    onClick={handleAnalyze}
                    disabled={analyzeMutation.isPending || analysisLoading}
                    className="p-2 hover:bg-purple-100 rounded-lg disabled:opacity-50"
                    title="AI 分析"
                  >
                    <Sparkles className={`h-4 w-4 ${analyzeMutation.isPending ? 'animate-pulse' : ''} text-purple-600`} />
                  </button>
                </>
              )}
            </div>
          </div>

          {/* 文档内容 */}
          {isEditing ? (
            <textarea
              value={editedContent}
              onChange={(e) => setEditedContent(e.target.value)}
              className="w-full min-h-[300px] px-3 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 text-sm"
              placeholder="文档内容"
            />
          ) : (
            <div className="p-4 bg-gray-50 rounded-lg">
              <p className="whitespace-pre-wrap text-sm text-gray-700">{document.content}</p>
            </div>
          )}

          {/* 元数据 */}
          <div className="flex items-center gap-4 text-xs text-gray-500">
            <span>创建时间: {new Date(document.created_at).toLocaleString()}</span>
            <span>更新时间: {new Date(document.updated_at).toLocaleString()}</span>
          </div>
        </div>
      </Card>

      {/* AI 分析结果 */}
      {(analysis || analyzeMutation.isPending || analysisLoading) && (
        <Card title="AI 分析结果" variant="bordered">
          {analyzeMutation.isPending || analysisLoading ? (
            <div className="flex items-center justify-center py-8">
              <Sparkles className="h-6 w-6 text-purple-600 animate-pulse mr-2" />
              <span className="text-gray-600">AI 分析中...</span>
            </div>
          ) : analysis ? (
            <div className="space-y-4">
              {/* 标签 */}
              {analysis.suggested_tags && analysis.suggested_tags.length > 0 && (
                <div className="flex items-start gap-2">
                  <Tag className="h-4 w-4 text-gray-500 mt-0.5" />
                  <div className="flex flex-wrap gap-2">
                    {analysis.suggested_tags.map((tag, idx) => (
                      <span
                        key={idx}
                        className="inline-flex items-center rounded-full bg-blue-100 px-3 py-1 text-sm font-medium text-blue-800"
                      >
                        {tag}
                      </span>
                    ))}
                  </div>
                </div>
              )}

              {/* 分类建议 */}
              {analysis.suggested_category && (
                <div className="flex items-start gap-2">
                  <FolderOpen className="h-4 w-4 text-gray-500 mt-0.5" />
                  <span className="text-gray-700">
                    建议分类:{' '}
                    <span className="font-medium text-gray-900">{analysis.suggested_category}</span>
                  </span>
                </div>
              )}

              {/* 摘要 */}
              {analysis.summary && (
                <div className="bg-purple-50 rounded-lg p-4">
                  <div className="flex items-start gap-2 mb-2">
                    <Sparkles className="h-4 w-4 text-purple-600 mt-0.5" />
                    <span className="font-medium text-gray-900">摘要</span>
                  </div>
                  <p className="text-sm text-gray-700 ml-6">{analysis.summary}</p>
                </div>
              )}

              {/* 提供商信息 */}
              <p className="text-xs text-gray-500">
                由 {analysis.provider} ({analysis.model}) 分析
              </p>
            </div>
          ) : null}
        </Card>
      )}

      {/* 转为待办 */}
      <Card variant="bordered">
        <div className="flex items-center justify-between">
          <div className="flex items-center gap-2">
            <CheckSquare className="h-5 w-5 text-green-600" />
            <div>
              <h3 className="font-medium text-gray-900">转为待办事项</h3>
              <p className="text-xs text-gray-500">将此文档内容转换为待办任务</p>
            </div>
          </div>
          <Button
            onClick={() => navigate(`/todos?createFromDocument=${id}`)}
            variant="secondary"
          >
            创建待办
          </Button>
        </div>
      </Card>
    </div>
  );
}