import { useState } from 'react';
import {
  Card,
  Table,
  Button,
  Input,
  Select,
  Tag,
  Space,
  Modal,
  Form,
  Popconfirm,
  Typography,
  Drawer,
  Upload,
  message,
} from 'antd';
import {
  PlusOutlined,
  SearchOutlined,
  EditOutlined,
  DeleteOutlined,
  EyeOutlined,
  CheckOutlined,
  StopOutlined,
  InboxOutlined,
  UploadOutlined,
} from '@ant-design/icons';
import {
  useKnowledgeArticles,
  useCreateArticle,
  useUpdateArticle,
  useDeleteArticle,
  usePublishArticle,
  useUnpublishArticle,
  useUploadKnowledgeFile,
} from '../../application';
import type { Article, CreateArticleParams } from '../../infrastructure';

const { Title, Paragraph } = Typography;
const { TextArea } = Input;

const CATEGORIES = [
  { value: 'QMAS', label: '优秀人才入境计划' },
  { value: 'GEP', label: '一般就业政策' },
  { value: 'IANG', label: '非本地毕业生留港/回港就业安排' },
  { value: 'TTPS', label: '科技人才入境计划' },
  { value: 'CIES', label: '资本投资者入境计划' },
  { value: 'TechTAS', label: '顶尖人才通行证计划' },
  { value: 'GENERAL', label: '通用知识' },
];

export function KnowledgePage() {
  const [searchText, setSearchText] = useState('');
  const [categoryFilter, setCategoryFilter] = useState<string>();
  const [isModalOpen, setIsModalOpen] = useState(false);
  const [isUploadModalOpen, setIsUploadModalOpen] = useState(false);
  const [isDrawerOpen, setIsDrawerOpen] = useState(false);
  const [selectedArticle, setSelectedArticle] = useState<Article | null>(null);
  const [isExtracting, setIsExtracting] = useState(false);
  const [articleSource, setArticleSource] = useState<'MANUAL' | 'EXTRACT'>('MANUAL');
  const [form] = Form.useForm();

  const { data, isLoading } = useKnowledgeArticles(categoryFilter);
  const createMutation = useCreateArticle();
  const updateMutation = useUpdateArticle();
  const deleteMutation = useDeleteArticle();
  const publishMutation = usePublishArticle();
  const unpublishMutation = useUnpublishArticle();
  const uploadMutation = useUploadKnowledgeFile();

  const handleEdit = (article: Article) => {
    setSelectedArticle(article);
    form.setFieldsValue({
      title: article.title,
      content: article.content,
      category: article.category,
      tags: article.tags,
    });
    setIsModalOpen(true);
  };

  const handleView = (article: Article) => {
    setSelectedArticle(article);
    setIsDrawerOpen(true);
  };

  const handleSubmit = (values: CreateArticleParams) => {
    if (selectedArticle) {
      updateMutation.mutate(
        { id: selectedArticle.id, ...values },
        {
          onSuccess: () => {
            setIsModalOpen(false);
            form.resetFields();
            setSelectedArticle(null);
          },
        }
      );
    } else {
      createMutation.mutate({ ...values, source: articleSource }, {
        onSuccess: () => {
          setIsModalOpen(false);
          form.resetFields();
          setArticleSource('MANUAL');
        },
      });
    }
  };

  const handleFileUpload = (file: File) => {
    setIsExtracting(true);
    uploadMutation.mutate(file, {
      onSuccess: (result) => {
        // 关闭上传弹窗，打开文章编辑弹窗（预填提取内容）
        setIsUploadModalOpen(false);
        setSelectedArticle(null);
        setArticleSource('EXTRACT');
        form.resetFields();
        form.setFieldsValue({
          title: result.suggestedTitle,
          content: result.extractedText,
        });
        setIsModalOpen(true);
        const info = result.pageCount
          ? `已提取 ${result.wordCount} 字（${result.pageCount} 页），请编辑后保存`
          : `已提取 ${result.wordCount} 字，请编辑后保存`;
        message.success(info);
      },
      onSettled: () => setIsExtracting(false),
    });
    return false;
  };

  const columns = [
    {
      title: '标题',
      dataIndex: 'title',
      key: 'title',
      render: (text: string, record: Article) => (
        <a onClick={() => handleView(record)}>{text}</a>
      ),
    },
    {
      title: '类别',
      dataIndex: 'category',
      key: 'category',
      render: (category: string) => {
        const cat = CATEGORIES.find((c) => c.value === category);
        return <Tag color="blue">{cat?.label || category}</Tag>;
      },
    },
    {
      title: '来源',
      dataIndex: 'source',
      key: 'source',
      render: (source: string) => {
        const sourceMap: Record<string, { color: string; label: string }> = {
          MANUAL: { color: 'green', label: '手动' },
          CRAWL: { color: 'orange', label: '爬取' },
          EXTRACT: { color: 'purple', label: '提取' },
          IMPORT: { color: 'cyan', label: '导入' },
        };
        const s = sourceMap[source] || { color: 'default', label: source };
        return <Tag color={s.color}>{s.label}</Tag>;
      },
    },
    {
      title: '状态',
      dataIndex: 'isPublished',
      key: 'isPublished',
      render: (isPublished: boolean) =>
        isPublished ? (
          <Tag color="success">已发布</Tag>
        ) : (
          <Tag color="default">草稿</Tag>
        ),
    },
    {
      title: '质量分',
      dataIndex: 'qualityScore',
      key: 'qualityScore',
      render: (score: number) => (
        <span
          className={
            score >= 70
              ? 'text-green-600'
              : score >= 40
              ? 'text-yellow-600'
              : 'text-red-600'
          }
        >
          {score}
        </span>
      ),
    },
    {
      title: '引用次数',
      dataIndex: 'citationCount',
      key: 'citationCount',
    },
    {
      title: '操作',
      key: 'action',
      render: (_: unknown, record: Article) => (
        <Space size="small">
          <Button
            type="text"
            icon={<EyeOutlined />}
            onClick={() => handleView(record)}
          />
          <Button
            type="text"
            icon={<EditOutlined />}
            onClick={() => handleEdit(record)}
          />
          {record.isPublished ? (
            <Popconfirm
              title="确定取消发布？"
              onConfirm={() => unpublishMutation.mutate(record.id)}
            >
              <Button type="text" icon={<StopOutlined />} />
            </Popconfirm>
          ) : (
            <Button
              type="text"
              icon={<CheckOutlined />}
              onClick={() => publishMutation.mutate(record.id)}
            />
          )}
          <Popconfirm
            title="确定删除此文章？"
            onConfirm={() => deleteMutation.mutate(record.id)}
          >
            <Button type="text" danger icon={<DeleteOutlined />} />
          </Popconfirm>
        </Space>
      ),
    },
  ];

  return (
    <div className="p-6">
      <Title level={4} className="mb-6">知识库管理</Title>

      <Card>
        <div className="flex justify-between mb-4">
          <Space>
            <Input
              placeholder="搜索文章"
              prefix={<SearchOutlined />}
              value={searchText}
              onChange={(e) => setSearchText(e.target.value)}
              style={{ width: 200 }}
            />
            <Select
              placeholder="选择类别"
              allowClear
              style={{ width: 180 }}
              value={categoryFilter}
              onChange={setCategoryFilter}
              options={CATEGORIES}
            />
          </Space>
          <Space>
            <Button
              icon={<UploadOutlined />}
              onClick={() => setIsUploadModalOpen(true)}
            >
              上传文件
            </Button>
            <Button
              type="primary"
              icon={<PlusOutlined />}
              onClick={() => {
                setSelectedArticle(null);
                setArticleSource('MANUAL');
                form.resetFields();
                setIsModalOpen(true);
              }}
            >
              新建文章
            </Button>
          </Space>
        </div>

        <Table
          columns={columns}
          dataSource={data?.items || []}
          rowKey="id"
          loading={isLoading}
          pagination={{
            total: data?.total || 0,
            pageSize: 20,
            showSizeChanger: false,
          }}
        />
      </Card>

      {/* 上传文件弹窗 */}
      <Modal
        title="上传文件"
        open={isUploadModalOpen}
        onCancel={() => {
          if (!isExtracting) setIsUploadModalOpen(false);
        }}
        footer={null}
        width={520}
      >
        <Upload.Dragger
          accept=".pdf,.docx,.txt,.md"
          showUploadList={false}
          beforeUpload={handleFileUpload}
          disabled={isExtracting}
        >
          <p className="ant-upload-drag-icon">
            <InboxOutlined />
          </p>
          <p className="ant-upload-text">
            {isExtracting ? '正在提取文本...' : '点击或拖拽文件到此区域'}
          </p>
          <p className="ant-upload-hint">
            支持 PDF、Word(.docx)、TXT、Markdown 格式，最大 200MB
          </p>
        </Upload.Dragger>
      </Modal>

      {/* 编辑/新建弹窗 */}
      <Modal
        title={
          selectedArticle
            ? '编辑文章'
            : articleSource === 'EXTRACT'
            ? '确认提取内容'
            : '新建文章'
        }
        open={isModalOpen}
        onCancel={() => {
          setIsModalOpen(false);
          setSelectedArticle(null);
          setArticleSource('MANUAL');
          form.resetFields();
        }}
        footer={null}
        width={800}
      >
        <Form form={form} layout="vertical" onFinish={handleSubmit}>
          <Form.Item
            name="title"
            label="标题"
            rules={[{ required: true, message: '请输入标题' }]}
          >
            <Input placeholder="文章标题" />
          </Form.Item>

          <Form.Item
            name="category"
            label="类别"
            rules={[{ required: true, message: '请选择类别' }]}
          >
            <Select options={CATEGORIES} placeholder="选择移民类别" />
          </Form.Item>

          <Form.Item name="tags" label="标签">
            <Select mode="tags" placeholder="输入标签后回车" />
          </Form.Item>

          <Form.Item
            name="content"
            label="内容"
            rules={[{ required: true, message: '请输入内容' }]}
          >
            <TextArea rows={12} placeholder="支持Markdown格式" />
          </Form.Item>

          <Form.Item className="mb-0 text-right">
            <Space>
              <Button onClick={() => setIsModalOpen(false)}>取消</Button>
              <Button
                type="primary"
                htmlType="submit"
                loading={createMutation.isPending || updateMutation.isPending}
              >
                保存
              </Button>
            </Space>
          </Form.Item>
        </Form>
      </Modal>

      {/* 预览抽屉 */}
      <Drawer
        title={selectedArticle?.title}
        open={isDrawerOpen}
        onClose={() => {
          setIsDrawerOpen(false);
          setSelectedArticle(null);
        }}
        width={600}
      >
        {selectedArticle && (
          <div>
            <div className="mb-4">
              <Tag color="blue">
                {CATEGORIES.find((c) => c.value === selectedArticle.category)
                  ?.label || selectedArticle.category}
              </Tag>
              {selectedArticle.isPublished ? (
                <Tag color="success">已发布</Tag>
              ) : (
                <Tag>草稿</Tag>
              )}
              <span className="ml-2 text-gray-500 text-sm">
                质量分: {selectedArticle.qualityScore} | 引用:{' '}
                {selectedArticle.citationCount}次
              </span>
            </div>

            {selectedArticle.tags?.length > 0 && (
              <div className="mb-4">
                {selectedArticle.tags.map((tag) => (
                  <Tag key={tag}>{tag}</Tag>
                ))}
              </div>
            )}

            <Paragraph className="text-gray-600 mb-4">
              {selectedArticle.summary}
            </Paragraph>

            <div className="whitespace-pre-wrap">{selectedArticle.content}</div>
          </div>
        )}
      </Drawer>
    </div>
  );
}