/**
 *
 * @author yutent<yutent.io@gmail.com>
 * @date 2022/04/09 18:26:35
 */

const vsc = require('vscode')
const { join, basename } = require('path')
const { parse } = require('url')
const http = require('http')
const http2 = require('http2')
const fs = require('iofs')
const { WebSocketServer } = require('ws')

const decode = decodeURIComponent
const statItem = vsc.window.createStatusBarItem(vsc.StatusBarAlignment.Left, 0)

const MIME_TYPES = {
  html: 'text/html;charset=utf-8',
  txt: 'text/plain;charset=utf-8',
  css: 'text/css;charset=utf-8',
  xml: 'text/xml;charset=utf-8',
  gif: 'image/gif',
  jpg: 'image/jpeg',
  webp: 'image/webp',
  tiff: 'image/tiff',
  png: 'image/png',
  svg: 'image/svg+xml',
  ico: 'image/x-icon',
  bmp: 'image/x-ms-bmp',
  js: 'application/javascript;charset=utf-8',
  json: 'application/json;charset=utf-8',
  mp3: 'audio/mpeg',
  ogg: 'audio/ogg',
  m4a: 'audio/x-m4a',
  mp4: 'video/mp4',
  webm: 'video/webm',
  ttf: 'font/font-ttf',
  woff: 'font/font-woff',
  woff2: 'font/font-woff2',
  wast: 'application/wast',
  wasm: 'application/wasm',
  other: 'application/octet-stream'
}

const SERVER_OPTIONS = { allowHTTP1: true }
const COMMON_HEADERS = {
  'Access-Control-Allow-Origin': '*',
  'Access-Control-Allow-Headers': '*',
  'Cache-Control': 'no-store',
  'X-Powered-By': 'VS Code simple.http'
}

const CONFIG_FILE = '.httpserver'

MIME_TYPES.htm = MIME_TYPES.html
MIME_TYPES.jpeg = MIME_TYPES.jpg
MIME_TYPES.tif = MIME_TYPES.tiff

let root
let enabled = false
let port = 23333
let baseUrl = 'http://127.0.0.1:' + port
let server
let ws = null
let domain
let isHttps = false

const HMR_SCRIPT = `
<script>
!(function http_hmr(){
  var ws = new WebSocket(\`\${location.protocol === 'https:' ? 'wss' : 'ws'}://\${location.host}/ws-http-hmr\`)
  ws.addEventListener('open', function (r) {
    if(http_hmr.closed){
      delete http_hmr.closed
      location.reload()
    }
    console.log('http.server hmr ready...')
  })
  ws.addEventListener('close', function(){
    http_hmr.closed = true
    setTimeout(http_hmr, 2000)
  })
  
  ws.addEventListener('message', function (ev) {
    location.reload()
  })
})()
</script>
`

class WebSocket {
  #ws = null // ws实例
  #queue = [] // 消息队列

  constructor(server) {
    if (server.listening) {
      let conn = new WebSocketServer({ server, path: '/ws-http-hmr' })
      conn.on('connection', ws => {
        this.#ws = ws
        if (this.#queue.length) {
          this.#queue = []
          this.send()
        }
      })
    }
  }

  send(msg = {}) {
    if (this.#ws) {
      this.#ws.send(JSON.stringify(msg))
    } else {
      this.#queue.push(msg)
    }
  }
}

function createServer() {
  if (port > 65535) {
    enabled = false
    return
  }
  console.log(`尝试使用${port}端口...`)

  server = (isHttps ? http2.createSecureServer : http.createServer)(
    isHttps ? SERVER_OPTIONS : void 0
  )

  server
    .on('request', function (req, res) {
      let pathname = parse(req.url).pathname.slice(1)
      let paths = pathname.split('/')

      pathname = decode(pathname) || 'index.html'

      if (pathname.endsWith('/')) {
        pathname += 'index.html'
      }

      let file = join(root, pathname)
      let stat = fs.stat(file)
      let ext = pathname.split('.').pop()
      let code

      for (let k in COMMON_HEADERS) {
        res.setHeader(k, COMMON_HEADERS[k])
      }

      if (stat.isFile()) {
        res.setHeader('accept-ranges', 'bytes')
        res.setHeader('content-type', MIME_TYPES[ext] || MIME_TYPES.other)

        if (ext === 'html') {
          code = fs
            .cat(file)
            .toString()
            .replace('</head>', HMR_SCRIPT + '</head>')

          res.setHeader('content-length', Buffer.byteLength(code))
        } else {
          res.setHeader('content-length', stat.size)
        }

        res.writeHead(200, isHttps ? void 0 : 'OK')

        if (ext === 'html') {
          res.end(code)
        } else {
          fs.origin.createReadStream(file).pipe(res)
        }
      } else {
        if (paths.length > 1 && paths[0].endsWith('.html')) {
          let rootFile = join(root, paths[0])
          if (fs.isfile(rootFile)) {
            code = fs
              .cat(rootFile)
              .toString()
              .replace('</head>', HMR_SCRIPT + '</head>')

            res.setHeader('accept-ranges', 'bytes')
            res.setHeader('content-type', MIME_TYPES.html)
            res.setHeader('content-length', Buffer.byteLength(code))
            res.writeHead(200, isHttps ? void 0 : 'OK')

            res.end(code)
            return
          }
        } else {
          let indexFile = join(root, 'index.html')
          if (fs.isfile(indexFile)) {
            code = fs
              .cat(indexFile)
              .toString()
              .replace('</head>', HMR_SCRIPT + '</head>')

            res.setHeader('accept-ranges', 'bytes')
            res.setHeader('content-type', MIME_TYPES.html)
            res.setHeader('content-length', Buffer.byteLength(code))
            res.writeHead(200, isHttps ? void 0 : 'OK')

            res.end(code)
            return
          }
        }
        res.setHeader('content-length', 0)
        res.setHeader('x-url', file)
        res.writeHead(404, isHttps ? void 0 : 'Not Found')
        res.end(null)
      }
    })
    .on('error', err => {
      console.log(`${port}端口被占用~~~`)
      port++
      createServer()
    })
    .on('listening', _ => {
      baseUrl = `http${isHttps ? 's' : ''}://${domain || '127.0.0.1'}:${port}`
      ws = new WebSocket(server)
      statItem.text = `http.server (🟢)`
      statItem.show()
    })
    .listen(port)

  return server
}

function __init__() {
  let folders = vsc.workspace.workspaceFolders
  let commonConfig = vsc.workspace.getConfiguration('HttpServer')

  enabled = false

  statItem.hide()

  if (folders && folders.length) {
    root = folders[0].uri.fsPath
  }

  if (server) {
    server.close()
    server.closeAllConnections()
    server = null
  }

  if (root) {
    let file = join(root, CONFIG_FILE)
    //
    if (fs.isfile(file)) {
      let conf = JSON.parse(fs.cat(file).toString())

      if (conf.root) {
        root = join(root, conf.root)
      }
      isHttps = conf.https || conf.http2

      if (conf.headers) {
        for (let k in conf.headers) {
          let _k = k.toLowerCase()
          if (['accept-ranges', 'content-type', 'content-length'].includes(_k)) {
            continue
          }
          COMMON_HEADERS[_k] = conf.headers[k]
        }
      }

      if (isHttps) {
        let key = conf.key || commonConfig.key
        let cert = conf.cert || commonConfig.cert

        if (key) {
          SERVER_OPTIONS.key = fs.cat(key)
        }
        if (cert) {
          SERVER_OPTIONS.cert = fs.cat(cert)
        }
      }

      domain = conf.domain || commonConfig.domain

      if (conf.enabled) {
        enabled = true
        port = conf.port || 23333

        createServer()
      } else {
        statItem.text = `http.server (🔴)`
        statItem.show()
      }
    }
  }
}

export function deactivate() {}

export function activate(ctx) {
  __init__()

  vsc.workspace.onDidChangeConfiguration(__init__)

  vsc.workspace.onDidSaveTextDocument(doc => {
    let file = doc.fileName
    if (file?.startsWith(root)) {
      if (basename(file) === CONFIG_FILE) {
        return __init__()
      }
      if (enabled) {
        ws.send()
      }
    }
  })

  let cmd = vsc.commands.registerCommand('HttpServer.open', _ => {
    if (enabled) {
      let editor = vsc.window.activeTextEditor
      if (editor) {
        let pathname = editor.document.uri.fsPath.slice(root.length)

        vsc.commands.executeCommand('vscode.open', baseUrl + pathname)
      }
    }
  })
  ctx.subscriptions.push(cmd)
}