[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)][ValidateSet('backend', 'worker', 'maintenance')][string]$Role,
    [Parameter(Mandatory = $true)][string]$ProjectRoot,
    [Parameter(Mandatory = $true)][string]$PythonPath,
    [Parameter(Mandatory = $true)][string]$RuntimeDirectory,
    [Parameter(Mandatory = $true)][string]$ConnectionFile,
    [int]$ApiPort = 8000
)
. (Join-Path $PSScriptRoot 'TaskHost.Common.ps1')
$plan = Get-PayrollTaskPlan -ProjectRoot $ProjectRoot -PythonPath $PythonPath -RuntimeDirectory $RuntimeDirectory `
    -ConnectionFile $ConnectionFile -TaskPath '\PayrollManagementSystem\' -ApiPort $ApiPort
if (Test-Path -LiteralPath $plan.StopFile) { exit 0 }
$env:T_PLUS_STOP_FILE = $plan.StopFile
$env:T_PLUS_ENABLED = 'true'
$env:T_PLUS_CONNECTION_FILE = $plan.ConnectionFile
$logs = Join-Path $plan.RuntimeDirectory 'logs'
New-Item -ItemType Directory -Path $logs -Force | Out-Null

function Limit-PayrollLog([string]$Path) {
    # current 供本次运行写入，previous 保留上一次；每分钟任务不再生成无限文件。
    $previous = [IO.Path]::ChangeExtension($Path, '.prev.log')
    if (Test-Path -LiteralPath $Path) {
        # .NET Framework 的 File.Replace 不接受 PowerShell 5 转换出的空备份路径。
        Move-Item -LiteralPath $Path -Destination $previous -Force
    }
}

$stdoutLog = Join-Path $logs "$Role.out.log"
$stderrLog = Join-Path $logs "$Role.err.log"
Limit-PayrollLog $stdoutLog
Limit-PayrollLog $stderrLog

$arguments = switch ($Role) {
    'backend' { '-m uvicorn app.main:app --host 127.0.0.1 --port ' + $ApiPort }
    'worker' { '-m app.cli tplus-worker --watch --connection-file ' + (Quote-TaskArgument $plan.ConnectionFile) + ' --stop-file ' + (Quote-TaskArgument $plan.StopFile) }
    'maintenance' { '-m app.cli tplus-maintain --once --connection-file ' + (Quote-TaskArgument $plan.ConnectionFile) + ' --stop-file ' + (Quote-TaskArgument $plan.StopFile) }
}
$process = Start-Process -FilePath $plan.PythonPath -ArgumentList $arguments -WorkingDirectory (Join-Path $plan.ProjectRoot 'backend') `
    -WindowStyle Hidden -PassThru -RedirectStandardOutput $stdoutLog `
    -RedirectStandardError $stderrLog
$processHandle = $process.Handle
while (-not $process.HasExited) {
    if ($Role -eq 'backend' -and (Test-Path -LiteralPath $plan.StopFile)) { Stop-Process -Id $process.Id -ErrorAction Stop }
    Start-Sleep -Seconds 1
    $process.Refresh()
}
$process.WaitForExit()
exit $process.ExitCode