const fsExtra = require('fs-extra')
const path = require('path')
const chalk = require('chalk')
const fs = require('fs')
/**
 * 将函数封装成promise
 */
const promisify = fn => {
  return function () {
    let args = arguments;
    return new Promise(function (resolve, reject) {
      [].push.call(args, function (err, result) {
        if (err) {
          console.log(err)
          reject(err);
        } else {
          resolve(result);
        }
      });
      fn.apply(null, args);
    });
  }
}

const readdir = promisify(fs.readdir)
const stat = promisify(fs.stat)

/**
 * 封装打印工具
 */
const {log} = console
const chalkTag = {
  info: msg => log([chalk.bgBlue.black(' INFO '), msg].join(' ')),
  done: msg => log([chalk.bgGreen.black(' DONE '), msg].join(' ')),
  warn: msg => log([chalk.bgYellow.black(' WARN '), msg].join(' ')),
  error: msg => log([chalk.bgRed.black(' ERROR '), msg].join(' ')),
}

/**
 * 遍历应用的方法
 */
const findApp = (dir, cb) => {
  fsExtra.ensureDirSync(dir)
  return readdir(dir).then(apps => {
    return Promise.all(apps.map(e => {
      let cPath = path.join(dir, e)
      return stat(cPath).then(state => {
        if (state.isDirectory()) {
          return findApp(cPath, cb)
        } else if (state.isFile()) {
          cb && cb(dir)
        }
      })
    }) || [])
  })
}
const findPages = (dir, cb) => {
  fsExtra.ensureDirSync(dir)
  return readdir(dir).then(apps => {
    return Promise.all(apps.map(e => {
      let cPath = path.join(dir, e)
      return stat(cPath).then(state => {
        if (state.isDirectory()) {
          return findPages(cPath, cb)
        } else if (state.isFile()) {
          cb && cb(cPath)
        }
      })
    }) || [])
  })
}
const copyFiles = (dir, source = 'src/mods') => {
  chalkTag.info(`开始扫描${source}...`)
  return new Promise(resolve => {
    fsExtra.emptyDir(dir, err => {
      if (!err) {
        fsExtra.copy(source, dir).then(() => {
          chalkTag.done(source + ' 扫描完毕')
          resolve()
        })
      }
    })
  })
}
module.exports = {findApp, chalkTag, fsExtra, copyFiles, fs, path, findPages}