param(
    [string]$Target
)

$ErrorActionPreference = "Stop"

Write-Host "===================================="
Write-Host " Unity CI Build (Windows Agent)"
Write-Host " Target: $Target"
Write-Host "===================================="

try {

    # -----------------------------
    # Load toolchain config
    # -----------------------------
    $config = Get-Content ".\ci\toolchain.json" | ConvertFrom-Json

    $unityVersion = $config.unityVersion
    $unityRoot = $config.windows.unityRoot

    $hubExe = "${env:ProgramFiles}\Unity Hub\Unity Hub.exe"

    if (!(Test-Path $hubExe)) {
        throw "Unity Hub not found at: $hubExe"
    }

    # -----------------------------
    # Ensure Unity is installed
    # -----------------------------
    $unityEditorPath = Join-Path $unityRoot "$unityVersion\Editor\Unity.exe"

    if (!(Test-Path $unityEditorPath)) {

        Write-Host "Unity $unityVersion not found. Installing via Unity Hub..."

        # Install Unity Editor
        & $hubExe -- --headless install `
            --version $unityVersion

        if ($LASTEXITCODE -ne 0) {
            throw "Failed to install Unity $unityVersion"
        }
    }

    Write-Host "Unity found: $unityEditorPath"

    # -----------------------------
    # Ensure required modules
    # -----------------------------
    # NOTE:
    # Unity Hub CLI installs modules per version.
    # These are cached per editor version, not reinstalled each build.

    $modules = $config.windows.modules

    Write-Host "Ensuring Unity modules: $($modules -join ', ')"

    foreach ($module in $modules) {

        Write-Host "Checking module: $module"

        # Check installed modules via Unity Hub
        $installed = & $hubExe -- --headless editors --installed

        if ($installed -notmatch "$unityVersion.*$module") {

            Write-Host "Installing module: $module"

            & $hubExe -- --headless install-modules `
                --version $unityVersion `
                --module $module

            if ($LASTEXITCODE -ne 0) {
                throw "Failed to install module: $module"
            }
        }
        else {
            Write-Host "Module already installed: $module"
        }
    }

    # -----------------------------
    # Resolve Unity build method
    # -----------------------------
    if (!$Target) {
        Write-Host "No Target Provided"
        exit
    }
    else {
        $method = switch ($Target) {
            "Windows" { "BuildScript.Windows" }
            "Android" { "BuildScript.Android" }
        }

        Write-Host "Using Unity method: $method"

        Write-Host "===================================================================="
        Write-Host "===================== Starting Unity Build ========================="
        Write-Host "===================================================================="

       $ErrorActionPreference = "Stop"

        # 1. Define paths
        $logFile = "$PWD/unity_build.log"
        $artifactLog = "$PWD/Builds/unity_build.log"

        New-Item -ItemType Directory -Force -Path "$PWD/BuildLog" | Out-Null

        # 2. Build arguments
        $unityArgs = @(
            "-batchmode",
            "-nographics",
            "-quit",
            "-projectPath", "$PWD",
            "-executeMethod", "$method",
            "-logFile", "$logFile",
            "-verbose"
        )

        Write-Host "Starting Unity..."
        Write-Host "Log: $logFile"

        # 3. Start Unity
        $process = Start-Process `
            -FilePath $unityEditorPath `
            -ArgumentList $unityArgs `
            -NoNewWindow `
            -PassThru

        # 4. Stream log live (simple + reliable)
        while (-not $process.HasExited) {
            if (Test-Path $logFile) {
                Get-Content $logFile -Tail 20 -ErrorAction SilentlyContinue | ForEach-Object {
                    Write-Host $_
                }
            }
            Start-Sleep -Milliseconds 500
        }

        $process.WaitForExit()

        # 5. Copy Log to Builds Folder
        Copy-Item $logFile $artifactLog -Force


        # 6. Exit handling
        if ($process.ExitCode -ne 0) {
            Write-Error "Unity build failed with exit code $($process.ExitCode)"
            exit $process.ExitCode
        }

        Write-Host "===================================="
        Write-Host " BUILD SUCCESS: $Target"
        Write-Host "===================================="
    }
}
catch {
    throw
} 
finally {
    Write-Host "Cleaning Up"
    # Stop-Process -Name "Unity", "Unity Hub" -Force
}