import fs from 'iofs'
import { join, dirname, parse } from 'path'
import Es from 'esbuild'
import { compileScss, parseJs, compileVue, parseHtml } from './compile-vue.js'

function readFile(file) {
  return (file && fs.cat(file)?.toString()) || ''
}

export default function compile(root = '', dist = '', conf = {}) {
  //
  const SOURCE_DIR = join(root, 'src')
  const PUBLIC_DIR = join(root, 'public')
  const DEPLOY_PATH = conf.base || '' // 部署目录, 默认是根目录部署
  const IS_MPA = Object.keys(conf.pages).length > 1
  const PAGES_PREFIX = Object.keys(conf.pages).map(it => `pages/${it}/`)
  const INJECT_SCSS = readFile(conf.inject?.scss)
  const LEGACY_MODE = !!conf.legacy

  let timeStart = Date.now()
  let template = fs.cat(join(process.env.PWD, 'index.html')).toString()

  let list = fs
    .ls(SOURCE_DIR, true)
    .map(it => ({
      name: it.slice(SOURCE_DIR.length + 1),
      path: it,
      ext: parse(it).ext
    }))
    .filter(it => {
      if (fs.isfile(it.path) && it.ext !== '') {
        if (IS_MPA && it.name.startsWith('pages/')) {
          if (PAGES_PREFIX.some(it => it.startsWith(it.name))) {
            return true
          } else {
            return false
          }
        }

        return it.path !== conf.inject?.scss
      }

      return false
    })

  let compileFiles = function (currentPage, page, files) {
    let options = {
      IS_MPA,
      currentPage,
      SOURCE_DIR,
      DEPLOY_PATH,
      INJECT_SCSS,
      LEGACY_MODE
    }

    for (let it of files) {
      // 入口文件, 特殊处理
      if (page && it.path === page.entry) {
        let entry = fs.cat(page.entry).toString()

        entry = parseJs(entry, conf.imports, { ...options, IS_ENTRY: true })

        let code = parseHtml(template, { page, imports: conf.imports, entry })

        fs.echo(code, join(dist, `${currentPage}.html`))
        continue
      }

      console.log('  解析 %s ...', it.name)

      let pageDir = IS_MPA && currentPage ? `pages/${currentPage}` : ''

      switch (it.ext) {
        case '.vue':
          {
            let code = compileVue(it.path, conf.imports, options)

            Es.transform(code, { minify: true }).then(r => {
              fs.echo(
                r.code,
                join(dist, 'assets/', pageDir, it.name.replace(/\.vue$/, '.js'))
              )
            })
          }
          break

        case '.js':
          {
            let code = fs.cat(it.path)

            code = parseJs(code + '', conf.imports, options)
            Es.transform(code, { minify: true }).then(r => {
              fs.echo(r.code, join(dist, 'assets/', pageDir, it.name))
            })
          }
          break

        case '.scss':
        case '.css':
          {
            let code = compileScss(it.path)
            if (!it.name.startsWith('assets')) {
              it.name = 'assets/' + it.name
            }
            fs.echo(code, join(dist, it.name.replace(/\.scss$/, '.css')))
          }
          break

        default:
          fs.cp(it.path, join(dist, it.name))
          break
      }
    }
  }

  // 优先处理静态目录, 之后的源码目录中, 以便如果有产生相同的文件名, 则覆盖静态目录中的文件
  if (fs.isdir(PUBLIC_DIR)) {
    console.log('\n正在处理静态资源 ...')
    fs.ls(PUBLIC_DIR, true).forEach(it => {
      let ext = parse(it).ext

      if (ext === '') {
        return
      }

      if (fs.isfile(it)) {
        let name = it.slice(PUBLIC_DIR.length + 1)
        console.log('  复制 %s ...', name)
        fs.cp(it, join(dist, name))
      }
    })
  }

  for (let currentPage in conf.pages) {
    let page = conf.pages[currentPage]
    let dir = dirname(page.entry)
    let files = list
    if (IS_MPA) {
      files = []
      fs.ls(dir, true).forEach(it => {
        if (fs.isdir(it)) {
          return
        }
        let idx = list.findIndex(_ => _?.path === it)
        let name = it.slice(dir.length + 1)
        let ext = parse(name).ext

        if (ext === '') {
          return
        }

        list[idx] = null

        files.push({
          name,
          path: it,
          ext
        })
      })
    }
    console.log('正在生成 %s ...', `${currentPage}.html`)
    compileFiles(currentPage, page, files)
  }

  list = list.filter(it => it)

  if (IS_MPA) {
    console.log('\n正在解析公共依赖 ...')
    compileFiles('', null, list)
  }

  console.log('\n页面处理完成, 耗时 %ss\n', (Date.now() - timeStart) / 1000)
}