import fm from 'front-matter';
import * as fs from 'fs-extra';
import * as glob from 'glob';
import * as path from 'path';
import { Demo, Example, ExampleTopic } from '../types';
import { getExampleAPI } from './api';
const examplesBaseDir = path.resolve(process.cwd(), 'examples');

/**
 * 获取某个案例下所有的 DEMO
 *
 * @param {string} exampleDir 案例路径
 * @returns {Demo[]} DEMO 列表
 * @author YuZhanglong <loveyzl1123@gmail.com>
 */
const getExampleDemos = (exampleDir: string) => {
  const demoMetaJSON = fs.readFileSync(path.resolve(exampleDir, 'demo', 'meta.json')).toString();
  const demoMeta: any[] = JSON.parse(demoMetaJSON).demos;
  const demos: Demo[] = demoMeta.map((item) => {
    const { title, screenshot, filename, new: isNew } = item;
    const id = filename
      .replace(/\.tsx?$/, '')
      .replace(/\.ts?$/, '')
      .replace(/\.jsx?$/, '')
      .replace(/\.js?$/, '');
    return {
      id,
      screenshot,
      source: fs.readFileSync(path.resolve(exampleDir, 'demo', filename)).toString(),
      title,
      filename,
      isNew: !!isNew,
    };
  });
  return demos;
};

/**
 * 获取某个案例主题下面的所有案例
 *
 * @param {string} topicPath 案例主题路径
 * @param {boolean} showAPIDoc 是否在示例页面显示 API 文档
 * @returns {Example[]} 案例列表
 * @author YuZhanglong <loveyzl1123@gmail.com>
 */
const getTopicExamples = (topicPath: string, showAPIDoc: boolean) => {
  const examplePaths = glob.sync(`${topicPath.replace(/\\/g, '/')}/*`).filter((item) => {
    return !item.endsWith('.js');
  });

  return examplePaths
    .map((item) => {
      const exampleMetaZh = fs.readFileSync(path.resolve(item, 'index.zh.md')).toString();
      const exampleMetaEn = fs.readFileSync(path.resolve(item, 'index.en.md')).toString();
      let api: null | { zh: string; en: string } = null;
      if (showAPIDoc) {
        api = {
          zh: getExampleAPI(path.resolve(item, 'API.zh.md')),
          en: getExampleAPI(path.resolve(item, 'API.en.md')),
        };
      }
      const exampleMetaZhContent: Record<string, any> = fm(exampleMetaZh);
      const exampleMetaEnContent: Record<string, any> = fm(exampleMetaEn);

      const example: Example = {
        demos: getExampleDemos(item),
        // 二级暂时无须 ICON，保留
        icon: '',
        id: <string>item.split('/').pop(),
        title: {
          en: exampleMetaEnContent.attributes.title,
          zh: exampleMetaZhContent.attributes.title,
        },
        api,
        childrenKey: 'demos',
        order: exampleMetaZhContent.attributes.order || 0,
      };
      return example;
    })
    .sort((a, b) => a.order - b.order);
};

/**
 * 获取案例页面的所有主题
 *
 * @returns {ExampleTopic[]} 案例主题列表
 * @author YuZhanglong <loveyzl1123@gmail.com>
 */
export const getExamplesPageTopics = (exampleTopics: ExampleTopic[], showAPIDoc: boolean) => {
  return exampleTopics.map(({ id, slug, title, icon }: ExampleTopic) => {
    const nid = (id || slug) as string;
    let examples: Example[] = [];

    try {
      examples = getTopicExamples(path.join(examplesBaseDir, nid), showAPIDoc);
    } catch (e) {
      console.warn(e);
    }
    return {
      id: nid,
      title,
      icon,
      examples,
      childrenKey: 'examples',
    };
  });
};

/**
 * 根据目录结构返回，所有的 example 页面，用于 buiild static
 */
export function getExamplePaths() {
  const exampleTopicPaths = glob.sync(`${examplesBaseDir}/*/*`);
  const paths = exampleTopicPaths.map((p) => p.replace(process.cwd(), ''));
  return [...paths, ...paths.map((p) => `/zh${p}`), ...paths.map((p) => `/en${p}`)];
}