const fs = require('fs').promises
const util = require('util')
const rimraf = util.promisify(require('rimraf'))
const path = require('path')
const SVGO = require('svgo')
const compiler = require('vue-template-compiler')
const { camelCase, upperFirst } = require('lodash')

const rawDir = '../src/assets/eva-icons'
const outputDir = '../src/components/EvaIcon'
const prefix = 'eva-icon'

const fullRawDir = path.join(__dirname, rawDir)
const fullOutputDir = path.join(__dirname, outputDir)

buildAllSVG(prefix, fullRawDir, fullOutputDir)

const svgoConfig = {
  onlyMatchedOnce: false,
  plugins: [
    {
      removeXMLNS: true
    },
    {
      removeAttrs: { attrs: '(stroke|fill|class)' }
    },
    { removeStyleElement: true },
    {
      addAttributesToSVGElement: {
        attribute: {
          fill: 'currentColor',
          width: '1em',
          height: '1em'
        }
      }
    }
  ]
}

const svgo = new SVGO(svgoConfig)

async function buildAllSVG(prefix, inputDir, outputDir) {
  try {
    await rimraf(outputDir)
    console.log('clear output dir')
    fs.mkdir(outputDir, { recursive: true })
  } catch (e) {
    console.log('no cache')
    console.log(e)
  }

  const files = await collectAllSubFilePath(inputDir)
  for (const filePath of files) {
    const file = await fs.readFile(filePath)
    const optimizedSVG = await (await svgo.optimize(file)).data
    const svgRender = compiler
      .compile(`<i aria-label="icon" class="${prefix}">${optimizedSVG}</i>`)
      .render.replace(/_/g, '_vm._')

    const fileBasename = path.basename(filePath, '.svg')
    const filename = upperFirst(camelCase(`${prefix}-${fileBasename}`))

    fs.writeFile(
      path.join(outputDir, `${filename}.js`),
      `export default {
  functional: true,
  render(_h,_vm){
    ${removeWith(svgRender)}
  }
}
`
    )

    fs.writeFile(
      path.join(outputDir, `${filename}.d.ts`),
      `declare const ${filename}: any;
export default ${filename};
`
    )

    fs.appendFile(
      path.join(outputDir, 'index.js'),
      `export { default as ${filename} } from './${filename}'
`
    )
    fs.appendFile(
      path.join(outputDir, 'index.d.ts'),
      `export { default as ${filename} } from './${filename}'
`
    )
  }
}

function removeWith(str) {
  const regex = /^with\(this\)\{(.*)}$/
  return regex.exec(str)[1]
}

/**
 * get all sub file path
 * @param {string} dirPath
 * @return {Promise<string[]>} allFilePath
 */
async function collectAllSubFilePath(dirPath) {
  const fileList = await fs.readdir(dirPath)
  const allFiles = []

  for (const filename of fileList) {
    const filePath = path.join(dirPath, filename)
    const fileStat = await fs.stat(filePath)
    if (fileStat.isDirectory()) {
      const subFileList = await collectAllSubFilePath(filePath)
      allFiles.push(...subFileList)
    } else {
      allFiles.push(filePath)
    }
  }
  return allFiles
}