$ErrorActionPreference = 'Stop'

param(
  [switch]$NoBrowser
)

$appRoot = Split-Path -Parent $MyInvocation.MyCommand.Path
$productName = 'SSH Manager'
$baseUrl = 'http://127.0.0.1:48080'
$healthUrl = "$baseUrl/api/auth/health"
$localRoot = Join-Path $env:LOCALAPPDATA 'SSHManager'
$dataDir = Join-Path $localRoot 'data'
$runtimeDir = Join-Path $localRoot 'runtime'
$logsDir = Join-Path $localRoot 'logs'
$stateFile = Join-Path $runtimeDir 'launcher-state.json'
$pidFile = Join-Path $runtimeDir 'app.pid'
$logFile = Join-Path $logsDir 'backend.log'
$jarPath = Join-Path $appRoot 'ssh-manager.jar'
$bundledJavaw = Join-Path $appRoot 'jre\bin\javaw.exe'
$bundledJava = Join-Path $appRoot 'jre\bin\java.exe'

function Ensure-Directory([string]$path) {
  if (-not (Test-Path $path)) {
    New-Item -ItemType Directory -Path $path | Out-Null
  }
}

function Test-Healthy {
  try {
    $response = Invoke-RestMethod -Uri $healthUrl -Method Get -TimeoutSec 2
    return $response.app -eq 'ssh-manager' -and $response.status -eq 'ok'
  } catch {
    return $false
  }
}

function Get-JavaCommand {
  if (Test-Path $bundledJavaw) {
    return $bundledJavaw
  }
  if (Test-Path $bundledJava) {
    return $bundledJava
  }

  $javaw = Get-Command javaw.exe -ErrorAction SilentlyContinue
  if ($javaw) {
    return $javaw.Source
  }

  $java = Get-Command java.exe -ErrorAction SilentlyContinue
  if ($java) {
    return $java.Source
  }

  throw '未找到可用的 Java 运行时，请重新安装带内置 JRE 的版本。'
}

function New-State {
  $jwtBytes = New-Object byte[] 48
  [Security.Cryptography.RandomNumberGenerator]::Create().GetBytes($jwtBytes)

  $encBytes = New-Object byte[] 32
  [Security.Cryptography.RandomNumberGenerator]::Create().GetBytes($encBytes)

  $state = @{
    jwtSecret = [Convert]::ToBase64String($jwtBytes)
    encryptionKey = [Convert]::ToBase64String($encBytes)
    createdAt = [DateTimeOffset]::UtcNow.ToUnixTimeMilliseconds()
  }

  $state | ConvertTo-Json | Set-Content -Path $stateFile -Encoding ASCII
  return $state
}

function Get-State {
  if (-not (Test-Path $stateFile)) {
    return New-State
  }

  $state = Get-Content -Path $stateFile -Raw | ConvertFrom-Json
  if (-not $state.jwtSecret -or -not $state.encryptionKey) {
    return New-State
  }

  return $state
}

function Clear-StalePid {
  if (-not (Test-Path $pidFile)) {
    return
  }

  $rawPid = Get-Content -Path $pidFile -Raw
  $pidInfo = $null

  try {
    $pidInfo = $rawPid | ConvertFrom-Json
  } catch {
    $legacyPid = 0
    if ([int]::TryParse($rawPid, [ref]$legacyPid)) {
      $pidInfo = @{
        pid = $legacyPid
        startedAt = 0
      }
    }
  }

  if (-not $pidInfo) {
    Remove-Item -Path $pidFile -Force -ErrorAction SilentlyContinue
    return
  }

  $process = Get-Process -Id ([int]$pidInfo.pid) -ErrorAction SilentlyContinue
  if (-not $process) {
    Remove-Item -Path $pidFile -Force -ErrorAction SilentlyContinue
    return
  }

  if ($pidInfo.startedAt -and $process.StartTime) {
    $processStartedAt = [DateTimeOffset]$process.StartTime
    if ($processStartedAt.ToUnixTimeMilliseconds() -ne [int64]$pidInfo.startedAt) {
      Remove-Item -Path $pidFile -Force -ErrorAction SilentlyContinue
    }
  }
}

Ensure-Directory $localRoot
Ensure-Directory $dataDir
Ensure-Directory $runtimeDir
Ensure-Directory $logsDir

if (-not (Test-Path $jarPath)) {
  throw "未找到程序包：$jarPath"
}

Clear-StalePid

if (Test-Healthy) {
  if (-not $NoBrowser) {
    Start-Process $baseUrl | Out-Null
  }
  exit 0
}

$state = Get-State
$javaCommand = Get-JavaCommand

$arguments = @(
  '-Dfile.encoding=UTF-8'
  '-Dserver.address=127.0.0.1'
  "-Dlogging.file.name=$logFile"
  "-DDATA_DIR=$dataDir"
  "-Dsshmanager.jwt-secret=$($state.jwtSecret)"
  "-Dsshmanager.encryption-key=$($state.encryptionKey)"
  '-jar'
  $jarPath
)

$process = Start-Process -FilePath $javaCommand -ArgumentList $arguments -WorkingDirectory $appRoot -PassThru
$pidInfo = @{
  pid = $process.Id
  startedAt = ([DateTimeOffset]$process.StartTime).ToUnixTimeMilliseconds()
}
$pidInfo | ConvertTo-Json | Set-Content -Path $pidFile -Encoding ASCII

for ($i = 0; $i -lt 45; $i++) {
  Start-Sleep -Seconds 1

  if (Test-Healthy) {
    if (-not $NoBrowser) {
      Start-Process $baseUrl | Out-Null
    }
    exit 0
  }

  $process.Refresh()
  if ($process.HasExited) {
    break
  }
}

if (-not $process.HasExited) {
  Stop-Process -Id $process.Id -Force -ErrorAction SilentlyContinue
}

throw "SSH Manager 启动失败，请检查日志：$logFile"