import commandLineUsage from 'command-line-usage';
import fs from 'fs';
import path from 'path';
import chalk from 'chalk';
import spawn from 'cross-spawn';
import cliMd from 'cli-html-c';
import marked from 'marked';
import { UNIVERSAL_README_CONFIG } from '../../shared/constant';

const getCommands = (store: any) => {
  const arr = [];
  for (const name in store) {
    const desc = store[name].desc || '';
    arr.push({
      colA: name,
      colB: (desc instanceof Function ? desc() : desc).replace(/({|})/g, (val: string) => escape(val))
    });
  }
  return arr;
};

const showHelp = (commands: Array<Record<string, any>>) => {
  const sections = [
    {
      header: 'Usage',
      content: '$ fef [options] [command]'
    },
    {
      header: 'Commands',
      content: {
        data: commands,
        options: {
          maxWidth: 60
        }
      }
    },
    {
      header: 'Options',
      optionList: [
        {
          name: 'version',
          description: 'Print version and exit successfully.'
        },
        {
          name: 'help',
          description: 'Print this help and exit successfully.'
        },
        {
          name: 'disable-check',
          description: 'Disable @feflow/cli and installed plugins check update'
        },
        {
          name: 'auto-update',
          description: 'Auto update @feflow/cli and installed plugins'
        }
      ]
    }
  ];
  const usage = commandLineUsage(sections);

  return usage;
};

const parseReadme = (path: any) => {
  let readmeText;
  if (fs.existsSync(path)) {
    try {
      readmeText = fs.readFileSync(path, 'utf8');
    } catch (e) {
      throw new Error(e);
    }
  }
  return cliMd(marked(readmeText));
};

module.exports = (ctx: any) => {
  ctx.commander.register('help', 'Help messages', () => {
    const { store } = ctx.commander;
    let cmd = ctx.args['_'][0];
    cmd = cmd && String.prototype.toLowerCase.call(cmd);
    // fef help xxx 的 case
    if (cmd) {
      if (Object.prototype.hasOwnProperty.call(store, cmd)) {
        const commandInfo = store[cmd];

        // 优先展示组件注册信息
        if (commandInfo.options && commandInfo.options.length) {
          const universalUsage = commandInfo.options[0];
          const { type, content } = universalUsage instanceof Function ?
              universalUsage() : universalUsage;

          // case 1: 多语言情况下 yml 有 usage 属性时，执行对应的内容
          if (type === 'usage') {
            spawn(content, {
              stdio: 'inherit',
              shell: true,
              windowsHide: true
            });
            return;
          }

          // case 2: 多语言情况下 yml 没有 usage 属性时，优先读取 readme 展示出来
          if (type === 'path') {
            const pluginConfigPath = path.join(
              content,
              UNIVERSAL_README_CONFIG
            );
            const readmeText = parseReadme(pluginConfigPath);

            if (readmeText) {
              console.log(readmeText);
              return;
            }

            // case 3: 多语言情况下既没有 usage，又没有 README.md，则展示插件的 desc
            console.log(commandInfo.desc);
            return;
          }

          // case 4: nodejs 且有写 options 的情况
          const usage = commandLineUsage(commandInfo.options);
          console.log(usage);
          return;
        }

        // case 5: nodejs 且没有写 options 的情况，直接展示插件的 desc
        console.log(commandInfo.desc);
        return;
      }

      console.log(
        chalk.yellow(
          `Command '${cmd}' not found in feflow. You need to install it first.`
        )
      );
      console.log(`Below is the usage of feflow.`);
    }

    // 打印 fef 的 usage
    const commands = getCommands(ctx.commander.store);
    const usage = showHelp(commands);
    console.log(usage);
    return;
  });
};