const { spawn } = require('child_process')
const { execSync } = require('child_process')
const path = require('path')
const fs = require('fs')

const config = require(path.join(__dirname, '..', '..', 'configs', 'config.js'))
let projectRoot = path.resolve(__dirname, '..', '..')
if (projectRoot.includes('app.asar') && !projectRoot.includes('app.asar.unpacked')) {
  projectRoot = projectRoot.replace('app.asar', 'app.asar.unpacked')
}
const adbPath = path.resolve(projectRoot, config.adbPath.path)
const scrcpyDir = path.dirname(adbPath)
const scrcpyPath = path.join(scrcpyDir, 'scrcpy.exe')
const pidFile = path.join(projectRoot, 'static', 'scrcpy-pid.json')

const action = process.argv[2]
const pidArg = process.argv[3]

/** 终止指定 PID 的进程 */
function killPidIfRunning(pid) {
  spawn('taskkill.exe', ['/F', '/PID', pid.toString()], {
    stdio: 'ignore',
    detached: true
  }).unref()
}

/** 从 tasklist 获取 scrcpy.exe 的 PID（用 bat start 启动后需轮询得到 pid） */
function getScrcpyPid() {
  const output = execSync('tasklist /FI "IMAGENAME eq scrcpy.exe" /FO CSV', { encoding: 'utf-8' })
  const lines = output.split('\n').filter(line => line.includes('scrcpy.exe'))
  if (lines.length === 0) return null
  const pidMatch = lines[0].match(/"(\d+)"/)
  return pidMatch ? parseInt(pidMatch[1]) : null
}

/** 判断是否为 IP（或 IP:port），用于无线设备选择器 */
function isDeviceIp(val) {
  return val && !/^\d+$/.test(val) && /[\d.]/.test(val)
}

/** 根据传入的 IP 得到 adb/scrcpy 设备选择器，无线默认 5555 */
function toDeviceSelector(ipOrSelector) {
  return ipOrSelector.includes(':') ? ipOrSelector : `${ipOrSelector}:5555`
}

/** 启动 scrcpy：先 adb connect（若有 IP），再用 scrcpy-noconsole.bat（start "" scrcpy.exe %*）无控制台启动 */
function startScrcpy() {
  if (fs.existsSync(pidFile)) {
    const { pid } = JSON.parse(fs.readFileSync(pidFile, 'utf-8'))
    killPidIfRunning(pid)
  }

  let deviceSelector = ''
  if (isDeviceIp(pidArg)) {
    deviceSelector = toDeviceSelector(pidArg)
    execSync(`"${adbPath}" connect ${deviceSelector}`, { encoding: 'utf-8', cwd: scrcpyDir })
  }

  const serial = deviceSelector || (pidArg && !/^\d+$/.test(pidArg) ? pidArg : '')
  const args = serial
    ? ['--pause-on-exit=if-error', '-s', serial]
    : ['-e', '--pause-on-exit=if-error']
  const argsStr = args.join(' ')
  const vbsPath = path.join(scrcpyDir, 'scrcpy-noconsole.vbs')
  execSync(`wscript "${vbsPath.replace(/"/g, '""')}" ${argsStr}`, { cwd: scrcpyDir })

  const sleep = (ms) => { const t = Date.now(); while (Date.now() - t < ms) {} }
  sleep(1500)
  const runningPid = getScrcpyPid()
  if (!runningPid) {
    console.log(JSON.stringify({ success: false, error: 'scrcpy did not appear in tasklist' }))
    process.exit(1)
  }
  fs.writeFileSync(pidFile, JSON.stringify({ pid: runningPid }), 'utf-8')
  console.log(JSON.stringify({ success: true, pid: runningPid }))
  process.exit(0)
}

/** 停止 scrcpy：有 pid 则 taskkill 并删文件，返回 action: 'stop'；无 pid 文件返回 action: 'none'，供前端区分是否继续执行 start */
function stopScrcpy() {
  if (!fs.existsSync(pidFile)) {
    console.log(JSON.stringify({ success: true, action: 'none' }))
    process.exit(0)
    return
  }
  const pid = JSON.parse(fs.readFileSync(pidFile, 'utf-8')).pid
  killPidIfRunning(pid)
  fs.unlinkSync(pidFile)
  console.log(JSON.stringify({ success: true, action: 'stop' }))
  process.exit(0)
}

switch (action) {
  case 'start':
    startScrcpy()
    break
  case 'stop':
    stopScrcpy()
    break
  default:
    console.log(JSON.stringify({ 
      success: false, 
      error: 'Usage: node screenshot.js [start|stop] [pid|deviceIp]' 
    }))
    process.exit(1)
}