param(
    [string]$LanIp = ''
)

$ErrorActionPreference = 'Stop'
$projectRoot = Split-Path -Parent $PSScriptRoot
$python = Join-Path $projectRoot '.venv\Scripts\python.exe'

if (-not (Test-Path -LiteralPath $python -PathType Leaf)) {
    throw "Project virtual environment was not found: $python"
}

if ([string]::IsNullOrWhiteSpace($LanIp)) {
    $network = Get-NetIPConfiguration |
        Where-Object {
            $_.NetAdapter.Status -eq 'Up' -and
            $_.IPv4DefaultGateway -and
            $_.IPv4Address.IPAddress -notlike '127.*' -and
            $_.IPv4Address.IPAddress -notlike '169.254.*' -and
            $_.IPv4Address.IPAddress -notlike '198.18.*'
        } |
        Select-Object -First 1

    if (-not $network) {
        throw 'No active LAN IPv4 address was found. Pass one explicitly, for example: .\start-local-lan.ps1 -LanIp 192.168.1.10'
    }
    $LanIp = $network.IPv4Address.IPAddress
}

$parsedIp = $null
if (-not [System.Net.IPAddress]::TryParse($LanIp, [ref]$parsedIp) -or
    $parsedIp.AddressFamily -ne [System.Net.Sockets.AddressFamily]::InterNetwork) {
    throw "Invalid IPv4 address: $LanIp"
}

$runtime = Join-Path $projectRoot '.runtime'
$yoloConfig = Join-Path $runtime 'ultralytics'
New-Item -ItemType Directory -Path $yoloConfig -Force | Out-Null

$ffmpeg = (& $python -c "import imageio_ffmpeg; print(imageio_ffmpeg.get_ffmpeg_exe())").Trim()
if (-not (Test-Path -LiteralPath $ffmpeg -PathType Leaf)) {
    throw "FFmpeg executable was not found: $ffmpeg"
}

$env:DJANGO_SETTINGS_MODULE = 'framework.settings'
$env:MONITOR_DEBUG = 'true'
$env:MONITOR_ALLOWED_HOSTS = "127.0.0.1,localhost,$LanIp"
$env:MONITOR_CSRF_TRUSTED_ORIGINS = "http://${LanIp}:10001"
$env:MONITOR_HTTPS = 'false'
$env:MONITOR_SERVICE_MODE = 'disabled'
$env:MONITOR_BOOTSTRAP_SERVICES = 'false'
$env:MONITOR_TELEMETRY_ENDPOINT = ''
$env:MONITOR_UPDATE_ENDPOINT = ''
$env:MONITOR_FFMPEG = $ffmpeg
$env:PYTHONUNBUFFERED = '1'
$env:YOLO_CONFIG_DIR = $yoloConfig
$env:YOLO_OFFLINE = 'true'
$env:YOLO_AUTOINSTALL = 'false'
$env:CI = 'true'

Write-Host "Starting LAN development server..."
Write-Host "Local: http://127.0.0.1:10001/login"
Write-Host "LAN:   http://${LanIp}:10001/login"
Write-Host 'Press Ctrl+C to stop.'

Push-Location $projectRoot
try {
    & $python 'manage.py' 'runserver' '0.0.0.0:10001' '--noreload'
    exit $LASTEXITCODE
}
finally {
    Pop-Location
}