import { useEffect, useState, useCallback, useMemo } from 'react';
import { useParams, useNavigate } from 'react-router-dom';
import { Button, Input, Select, Space, message, Spin, Upload } from 'antd';
import { ArrowLeftOutlined, SaveOutlined, SendOutlined, UploadOutlined } from '@ant-design/icons';
import { Editor, Toolbar } from '@wangeditor/editor-for-react';
import type { IDomEditor, IEditorConfig, IToolbarConfig } from '@wangeditor/editor';
import {
  articleApi,
  articleCategoryApi,
  articleTagApi,
  type Article,
  type ArticleTagItem,
} from '../../api/health/articles';
import { useThemeMode } from '../../hooks/useThemeMode';
import { AuthButton } from '../../components/AuthButton';
import client, { handleApiError } from '../../api/client';
import '@wangeditor/editor/dist/css/style.css';

export default function ArticleEditor() {
  const { id } = useParams<{ id: string }>();
  const navigate = useNavigate();
  const isEdit = Boolean(id);
  const isDark = useThemeMode();

  // 表单状态
  const [title, setTitle] = useState('');
  const [summary, setSummary] = useState('');
  const [content, setContent] = useState('');
  const [coverImage, setCoverImage] = useState('');
  const [slug, setSlug] = useState('');
  const [categoryId, setCategoryId] = useState<string | undefined>(undefined);
  const [selectedTagIds, setSelectedTagIds] = useState<string[]>([]);
  const [sortOrder, setSortOrder] = useState(0);
  const [version, setVersion] = useState(0);

  // 选项数据
  const [categories, setCategories] = useState<{ id: string; name: string }[]>([]);
  const [tags, setTags] = useState<ArticleTagItem[]>([]);

  // UI 状态
  const [loading, setLoading] = useState(false);
  const [saving, setSaving] = useState(false);
  const [editor, setEditor] = useState<IDomEditor | null>(null);

  // 加载分类和标签
  useEffect(() => {
    const fetchOptions = async () => {
      try {
        const [cats, tagList] = await Promise.all([
          articleCategoryApi.list(),
          articleTagApi.list(),
        ]);
        setCategories(cats.map((c) => ({ id: c.id, name: c.name })));
        setTags(tagList);
      } catch {
        // 选项加载失败不阻塞
      }
    };
    fetchOptions();
  }, []);

  // 编辑模式：加载现有文章
  useEffect(() => {
    if (!id) return;
    const fetchArticle = async () => {
      setLoading(true);
      try {
        const article: Article = await articleApi.get(id);
        setTitle(article.title);
        setSummary(article.summary || '');
        setContent(article.content || '');
        setCoverImage(article.cover_image || '');
        setSlug(article.slug || '');
        setCategoryId(article.category_id);
        setSelectedTagIds(article.tags?.map((t) => t.id) || []);
        setSortOrder(article.sort_order);
        setVersion(article.version);
      } catch {
        message.error('加载文章失败');
        navigate('/health/articles');
      } finally {
        setLoading(false);
      }
    };
    fetchArticle();
  }, [id, navigate]);

  // 编辑器配置
  const toolbarConfig = useMemo<Partial<IToolbarConfig>>(
    () => ({
      excludeKeys: [
        'group-video',
        'insertLink',
        'editLink',
        'unLink',
        'viewLink',
        'codeView',
      ],
    }),
    [],
  );

  const editorConfig = useMemo<Partial<IEditorConfig>>(
    () => ({
      placeholder: '请输入文章内容...',
      MENU_CONF: {
        uploadImage: {
          async customUpload(file: File, insertFn: (url: string, alt?: string, href?: string) => void) {
            try {
              const formData = new FormData();
              formData.append('file', file);
              const { data: result } = await client.post('/upload', formData, {
                headers: { 'Content-Type': 'multipart/form-data' },
              });
              const url: string = result.data.url;
              const token = localStorage.getItem('access_token');
              const urlWithToken = token ? `${url}?token=${token}` : url;
              insertFn(urlWithToken, file.name, urlWithToken);
            } catch {
              message.error('图片上传失败');
            }
          },
        },
      },
    }),
    [],
  );

  // 及时销毁编辑器
  useEffect(() => {
    return () => {
      if (editor) {
        editor.destroy();
        setEditor(null);
      }
    };
  }, [editor]);

  const handleSave = useCallback(async () => {
    if (!title.trim()) {
      message.warning('请输入文章标题');
      return;
    }
    setSaving(true);
    try {
      if (isEdit && id) {
        await articleApi.update(id, {
          title,
          summary: summary || undefined,
          content,
          cover_image: coverImage || undefined,
          slug: slug || undefined,
          category_id: categoryId,
          tag_ids: selectedTagIds,
          sort_order: sortOrder,
          version,
        });
        message.success('文章已保存');
        // 重新加载以获取新 version
        const updated = await articleApi.get(id);
        setVersion(updated.version);
      } else {
        await articleApi.create({
          title,
          summary: summary || undefined,
          content,
          cover_image: coverImage || undefined,
          slug: slug || undefined,
          category_id: categoryId,
          tag_ids: selectedTagIds,
          sort_order: sortOrder,
        });
        message.success('文章已创建');
        // 返回列表页，避免 WangEditor 全局 toolbar 注册导致同组件内重复初始化
        navigate('/health/articles');
      }
    } catch (err: unknown) {
      handleApiError(err, '保存失败');
    } finally {
      setSaving(false);
    }
  }, [
    id, isEdit, title, summary, content, coverImage, slug, categoryId,
    selectedTagIds, sortOrder, version, navigate,
  ]);

  const handleSubmit = useCallback(async () => {
    if (!title.trim()) {
      message.warning('请输入文章标题');
      return;
    }
    setSaving(true);
    try {
      // 先保存
      let currentVersion = version;
      if (isEdit && id) {
        await articleApi.update(id, {
          title,
          summary: summary || undefined,
          content,
          cover_image: coverImage || undefined,
          slug: slug || undefined,
          category_id: categoryId,
          tag_ids: selectedTagIds,
          sort_order: sortOrder,
          version,
        });
        const updated = await articleApi.get(id);
        currentVersion = updated.version;
        setVersion(updated.version);
      } else {
        const _created = await articleApi.create({
          title,
          summary: summary || undefined,
          content,
          cover_image: coverImage || undefined,
          slug: slug || undefined,
          category_id: categoryId,
          tag_ids: selectedTagIds,
          sort_order: sortOrder,
        });
        currentVersion = _created.version;
        setVersion(_created.version);
        await articleApi.submit(_created.id, currentVersion);
        message.success('已提交审核');
        navigate('/health/articles');
        return;
      }
      // 编辑模式提交审核
      if (id) {
        await articleApi.submit(id, currentVersion);
      }
      message.success('已提交审核');
      navigate('/health/articles');
    } catch (err: unknown) {
      handleApiError(err, '提交审核失败');
    } finally {
      setSaving(false);
    }
  }, [
    id, isEdit, title, summary, content, coverImage, slug, categoryId,
    selectedTagIds, sortOrder, version, navigate,
  ]);

  if (loading) {
    return (
      <div style={{ display: 'flex', justifyContent: 'center', padding: 100 }}>
        <Spin size="large" />
      </div>
    );
  }

  return (
    <div>
      {/* 页面标题栏 */}
      <div className="erp-page-header">
        <Space size={12}>
          <Button
            type="text"
            icon={<ArrowLeftOutlined />}
            onClick={() => navigate('/health/articles')}
          />
          <div>
            <h4 style={{ margin: 0 }}>{isEdit ? '编辑文章' : '新建文章'}</h4>
          </div>
        </Space>
        <Space size={8}>
          <AuthButton code="health.articles.manage">
            <Button
              icon={<SaveOutlined />}
              onClick={handleSave}
              loading={saving}
            >
              保存草稿
            </Button>
          </AuthButton>
          <AuthButton code="health.articles.manage">
            <Button
              type="primary"
              icon={<SendOutlined />}
              onClick={handleSubmit}
              loading={saving}
            >
              提交审核
            </Button>
          </AuthButton>
        </Space>
      </div>

      {/* 主体布局: 左侧编辑区 + 右侧设置面板 */}
      <div style={{ display: 'flex', gap: 16, alignItems: 'flex-start' }}>
        {/* 左侧: 富文本编辑器 — key 变化时强制重新挂载，防止 WangEditor toolbar 重复创建 */}
        <div
          key={id ?? 'new'}
          style={{
            flex: 1,
            background: isDark ? '#111827' : '#FFFFFF',
            borderRadius: 12,
            border: `1px solid ${isDark ? '#0f172a' : '#f8fafc'}`,
            overflow: 'hidden',
          }}
        >
          <div
            style={{
              borderBottom: `1px solid ${isDark ? '#1e293b' : '#f1f5f9'}`,
              zIndex: 100,
            }}
          >
            <Toolbar
              editor={editor}
              defaultConfig={toolbarConfig}
              mode="default"
              style={{
                background: isDark ? '#0f172a' : '#f8fafc',
                borderBottom: `1px solid ${isDark ? '#1e293b' : '#e2e8f0'}`,
              }}
            />
          </div>
          <div style={{ height: 600, overflowY: 'auto' }}>
            <Editor
              defaultConfig={editorConfig}
              value={content}
              onCreated={setEditor}
              onChange={(editorInstance) => setContent(editorInstance.getHtml())}
              mode="default"
              style={{
                minHeight: 500,
                background: isDark ? '#111827' : '#FFFFFF',
                color: isDark ? '#e2e8f0' : '#1e293b',
              }}
            />
          </div>
        </div>

        {/* 右侧: 设置面板 */}
        <div
          style={{
            width: 320,
            flexShrink: 0,
            background: isDark ? '#111827' : '#FFFFFF',
            borderRadius: 12,
            border: `1px solid ${isDark ? '#0f172a' : '#f8fafc'}`,
            padding: 20,
            display: 'flex',
            flexDirection: 'column',
            gap: 16,
          }}
        >
          {/* 标题 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              文章标题 <span style={{ color: '#dc2626' }}>*</span>
            </label>
            <Input
              value={title}
              onChange={(e) => setTitle(e.target.value)}
              placeholder="请输入文章标题"
              maxLength={200}
              showCount
            />
          </div>

          {/* 分类 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              分类
            </label>
            <Select
              value={categoryId}
              onChange={setCategoryId}
              placeholder="选择分类"
              allowClear
              style={{ width: '100%' }}
              options={categories.map((c) => ({ label: c.name, value: c.id }))}
            />
          </div>

          {/* 标签 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              标签
            </label>
            <Select
              mode="multiple"
              value={selectedTagIds}
              onChange={setSelectedTagIds}
              placeholder="选择标签"
              allowClear
              style={{ width: '100%' }}
              options={tags.map((t) => ({ label: t.name, value: t.id }))}
              maxTagCount={5}
            />
          </div>

          {/* 摘要 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              摘要
            </label>
            <Input.TextArea
              value={summary}
              onChange={(e) => setSummary(e.target.value)}
              placeholder="请输入文章摘要"
              rows={3}
              maxLength={500}
              showCount
            />
          </div>

          {/* 封面图 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              封面图
            </label>
            <Space.Compact style={{ width: '100%' }}>
              <Input
                value={coverImage}
                onChange={(e) => setCoverImage(e.target.value)}
                placeholder="请输入封面图片 URL 或上传文件"
                style={{ flex: 1 }}
              />
              <Upload
                accept="image/*"
                showUploadList={false}
                beforeUpload={async (file) => {
                  try {
                    const formData = new FormData();
                    formData.append('file', file);
                    const { data: result } = await client.post('/upload', formData, {
                      headers: { 'Content-Type': 'multipart/form-data' },
                    });
                    setCoverImage(result.data.url);
                    message.success('封面图上传成功');
                  } catch {
                    message.error('封面图上传失败');
                  }
                  return false;
                }}
              >
                <Button icon={<UploadOutlined />}>上传</Button>
              </Upload>
            </Space.Compact>
            {coverImage && (
              <div
                style={{
                  marginTop: 8,
                  borderRadius: 8,
                  overflow: 'hidden',
                  border: `1px solid ${isDark ? '#1e293b' : '#e2e8f0'}`,
                }}
              >
                <img
                  src={coverImage}
                  alt="封面预览"
                  style={{ width: '100%', height: 120, objectFit: 'cover' }}
                  onError={(e) => {
                    (e.target as HTMLImageElement).style.display = 'none';
                  }}
                />
              </div>
            )}
          </div>

          {/* Slug */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              URL 别名 (Slug)
            </label>
            <Input
              value={slug}
              onChange={(e) => setSlug(e.target.value)}
              placeholder="例如: health-tips-for-elderly"
            />
          </div>

          {/* 排序 */}
          <div>
            <label
              style={{
                display: 'block',
                fontSize: 13,
                fontWeight: 500,
                marginBottom: 6,
                color: isDark ? '#94a3b8' : '#475569',
              }}
            >
              排序
            </label>
            <Input
              type="number"
              value={sortOrder}
              onChange={(e) => setSortOrder(Number(e.target.value))}
              placeholder="0"
            />
          </div>
        </div>
      </div>
    </div>
  );
}