import { Component, createSignal, createEffect, onCleanup, Show, createResource } from 'solid-js';
import { parseMarkdown } from '../markdown';
import { fetchData, extractSection } from '../data-loader';

export interface ArticleProps {
  src: string;
  section?: string;  // 指定要显示的标题（不含 #）
  onLoaded?: () => void;
  onError?: (error: Error) => void;
}

async function fetchArticleContent(params: { src: string; section?: string }): Promise<string> {
  const text = await fetchData(params.src);
  // 如果指定了 section，提取对应内容
  return params.section ? extractSection(text, params.section) : text;
}

/**
 * Article 组件
 * 用于将特定 src 位置的 md 文件显示为 markdown 文章
 */
export const Article: Component<ArticleProps> = (props) => {
  const [content, { refetch }] = createResource(
    () => ({ src: props.src, section: props.section }),
    fetchArticleContent
  );

  let articleRef: HTMLArticleElement | undefined;

  createEffect(() => {
    const data = content();
    if (data) {
      props.onLoaded?.();
    }
  });

  onCleanup(() => {
    // 清理时清空内容，触发内部组件的销毁
  });

  return (
    <article ref={articleRef} class="prose" data-src={props.src}>
      <Show when={content.loading}>
        <div class="text-gray-500">加载中...</div>
      </Show>
      <Show when={content.error}>
        <div class="text-red-500">加载失败：{content.error?.message}</div>
      </Show>
      <Show when={!content.loading && !content.error && content()}>
        <div innerHTML={parseMarkdown(content()!)} />
      </Show>
    </article>
  );
};

export default Article;