const path = require('path')
const fs = require('fs')

class BuildLocales {
  constructor() {
    this.localesFolderPath = './src/locales' // 指定多语言源码目录
    this.outputFileName = 'locales/index.json' // 输出构建后的多语言
  }

  apply(compiler) {
    compiler.hooks.emit.tapAsync('BuildLocales', (compilation, callback) => {
      const locales = fs.readdirSync(this.localesFolderPath)
      const mergedData = {}

      locales.forEach(file => {
        if (path.extname(file) === '.json') {
          const localePath = path.join(this.localesFolderPath, file) // 文件路径
          const lang = path.parse(localePath).name // 语言如en、zh-CN、sv-SE等
          const langData = fs.readFileSync(localePath, 'utf8') // 语言文件中的多语言配置
          const jsonData = JSON.parse(langData) // 转换为json数据
          Object.assign(mergedData, { [lang]: jsonData }) // 语言作为key
        }
      })

      const outputFilePath = path.join(path.resolve(__dirname, '../../dist/'), this.outputFileName)
      const outputData = JSON.stringify(mergedData, null, 2)

      const dirPath = path.dirname(outputFilePath) // 提取目录
      if (!fs.existsSync(dirPath)) {
        // 判断是否存在目录
        fs.mkdir(dirPath, { recursive: true }, err => {
          // 创建目录
          if (err) {
            console.error('构建多语言文件报错:', err)
          } else {
            fs.writeFileSync(outputFilePath, outputData) // 写入文件
          }
        })
      }

      callback()
    })
  }
}

const BuildLocalesPlugin = ({ wpChain }) => {
  wpChain.plugin('BuildLocales').use(BuildLocales)
}

module.exports = BuildLocalesPlugin