param(
  [int]$Port = 7001,
  [string]$HostAddress = "0.0.0.0",
  [switch]$NoPause
)

$ErrorActionPreference = "Stop"
$Root = Split-Path -Parent $PSScriptRoot
$VenvPython = Join-Path $Root ".venv\Scripts\python.exe"
$InstallScript = Join-Path $PSScriptRoot "install_offline.ps1"

function Wait-BeforeExit {
  if (-not $NoPause) {
    Write-Host ""
    Read-Host "Press Enter to exit"
  }
}

function Test-PortAvailable {
  param([int]$CheckPort)
  $listener = Get-NetTCPConnection -LocalPort $CheckPort -State Listen -ErrorAction SilentlyContinue
  if ($listener) {
    $pids = ($listener | Select-Object -ExpandProperty OwningProcess -Unique) -join ", "
    throw "Port $CheckPort is already in use. Owning process PID: $pids"
  }
}

function Test-EnvironmentReady {
  if (-not (Test-Path $VenvPython)) {
    return $false
  }
  & $VenvPython -c "import fastapi, uvicorn, xlrd, xlwt, xlutils, httpx, yaml" 2>$null
  return ($LASTEXITCODE -eq 0)
}

try {
  Set-Location $Root

  if (-not (Test-EnvironmentReady)) {
    Write-Host "Runtime environment is missing or incomplete. Installing now..." -ForegroundColor Yellow
    powershell -NoProfile -ExecutionPolicy Bypass -File $InstallScript -NoPause
    if ($LASTEXITCODE -ne 0) {
      throw "Automatic environment installation failed. See the error above."
    }
  }

  Test-PortAvailable -CheckPort $Port

  Write-Host ""
  Write-Host "Starting PCFAnalysis service" -ForegroundColor Cyan
  Write-Host "Bind URL: http://$HostAddress`:$Port"
  Write-Host "Local URL: http://127.0.0.1`:$Port"
  Write-Host "Press Ctrl+C in this window to stop the service."
  Write-Host ""

  & $VenvPython -m uvicorn app.main:app --host $HostAddress --port $Port
  if ($LASTEXITCODE -ne 0) {
    throw "Service exited with code: $LASTEXITCODE"
  }
} catch {
  Write-Host ""
  Write-Host "Startup failed:" -ForegroundColor Red
  Write-Host $_.Exception.Message -ForegroundColor Red
  exit 1
} finally {
  Wait-BeforeExit
}