import React, { Children, cloneElement } from 'react';
import { Link } from 'react-router';
import * as utils from '../utils';
import { getTagName, getChildren } from 'jsonml.js/lib/utils';
import { Timeline } from 'antd';

export default class Article extends React.Component {
  componentDidMount() {
    this.componentDidUpdate();
  }
  componentDidUpdate() {
    const { chinese, english } = this.props.content.meta;
    utils.setTitle(`${chinese || english} - Ant Design`);
  }
  getTimelineFromArticle(article) {
    const { content } = this.props;
    const { meta } = content;
    if (!meta.timeline) {
      return article;
    }
    const timelineItems = [];
    let temp = [];
    Children.forEach(article.props.children, (child, i) => {
      if (child.type === 'h2' && temp.length > 0) {
        timelineItems.push(<Timeline.Item key={i}>{temp}</Timeline.Item>);
        temp = [];
      }
      temp.push(child);
    });
    return cloneElement(article, {
      children: <Timeline>{timelineItems}</Timeline>,
    });
  }
  render() {
    const { content, location } = this.props;
    const jumper = content.description.filter((node) => {
      return getTagName(node) === 'h2';
    }).map((node) => {
      return (
        <li key={getChildren(node)[0]}>
          <Link to={{ pathname: location.pathname, query: { scrollTo: getChildren(node)[0] } }}>
          {utils.jsonmlToComponent(location.pathname, getChildren(node)[0])}
          </Link>
        </li>
      );
    });

    const { meta, intro, description } = content;

    return (
      <article className="markdown">
        <h1>
          {meta.english} {meta.chinese}
          {
            !meta.subtitle ? null :
              <span className="subtitle">{meta.subtitle}</span>
          }
        </h1>
        {
          !intro ? null :
            utils.jsonmlToComponent(
              location.pathname,
              ['section', { className: 'markdown' }].concat(intro)
            )
        }
        {
          (jumper.length > 0 && meta.toc !== false) ?
            <section className="toc"><ul>{jumper}</ul></section> :
            null
        }
        {
          this.getTimelineFromArticle(utils.jsonmlToComponent(
            location.pathname,
            ['section', { className: 'markdown' }].concat(description)
          ))
        }
      </article>
    );
  }
}