[CmdletBinding()]
param(
    [string]$RepoRoot = (Split-Path -Parent $PSScriptRoot),
    [string]$BuildDir = "",
    [string]$Config = "Debug",
    [switch]$SkipBuild,
    [switch]$IncludeSmoke,
    [switch]$SkipCtestEnumerate
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

function Resolve-NormalizedPath {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Path
    )

    if (Test-Path -LiteralPath $Path) {
        return (Resolve-Path -LiteralPath $Path).Path
    }

    return [System.IO.Path]::GetFullPath($Path)
}

function Join-NormalizedPath {
    param(
        [Parameter(Mandatory = $true)]
        [string[]]$Parts
    )

    return [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($Parts))
}

function Assert-PathExists {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Path,
        [Parameter(Mandatory = $true)]
        [string]$Label
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        throw "$Label not found: $Path"
    }
}

function Invoke-NativeStep {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Name,
        [Parameter(Mandatory = $true)]
        [string]$FilePath,
        [string[]]$Arguments = @()
    )

    Write-Host "==> $Name" -ForegroundColor Cyan
    & $FilePath @Arguments
    $exitCode = $LASTEXITCODE
    if ($exitCode -ne 0) {
        throw "$Name failed with exit code $exitCode."
    }
}

function Invoke-CtestEnumeration {
    param(
        [Parameter(Mandatory = $true)]
        [string]$BuildDir,
        [Parameter(Mandatory = $true)]
        [string]$Config
    )

    Write-Host "==> Enumerate CTest registry" -ForegroundColor Cyan
    $output = & ctest --test-dir $BuildDir -N -C $Config 2>&1
    $exitCode = $LASTEXITCODE
    if ($exitCode -ne 0) {
        $output | ForEach-Object { Write-Host $_ }
        throw "Enumerate CTest registry failed with exit code $exitCode."
    }

    $lines = $output | ForEach-Object { $_.ToString() }
    $registeredCount = ($lines | Where-Object { $_ -match '^\s*Test\s+#\d+:' }).Count
    $notBuiltCount = ($lines | Where-Object { $_ -match '_NOT_BUILT' }).Count
    $totalLine = $lines | Where-Object { $_ -match '^Total Tests:\s+\d+' } | Select-Object -Last 1
    if ($null -ne $totalLine) {
        Write-Host ("{0}; NOT_BUILT placeholders: {1}" -f $totalLine.Trim(), $notBuiltCount) `
            -ForegroundColor DarkGray
    } else {
        Write-Host ("CTest enumeration completed; registered tests: {0}; NOT_BUILT placeholders: {1}" `
            -f $registeredCount, $notBuiltCount) -ForegroundColor DarkGray
    }
}

$RepoRoot = Resolve-NormalizedPath -Path $RepoRoot
if ([string]::IsNullOrWhiteSpace($BuildDir)) {
    $BuildDir = Join-NormalizedPath -Parts @($RepoRoot, "build")
} else {
    $BuildDir = Resolve-NormalizedPath -Path $BuildDir
}

$ctestRoot = Join-NormalizedPath -Parts @($BuildDir, "CTestTestfile.cmake")
Assert-PathExists -Path $ctestRoot -Label "CTest root"

$scriptingExe = Join-NormalizedPath -Parts @(
    $BuildDir, "tests", "Scripting", $Config, "scripting_tests.exe")
$windowingExe = Join-NormalizedPath -Parts @(
    $BuildDir, "tests", "UI", "Editor", "unit", $Config, "editor_windowing_phase1_tests.exe")

$srpValidationTests = @(
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeRuntimeExposesDefaultNativeBackendPolicy",
    "MonoScriptRuntimeTest.ScriptCoreUniversalRenderPipelineAssetExposesDefaultNativeBackendPolicy",
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeUsesDefaultRendererSelectionForNativeBackendPolicy",
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeUsesCameraRendererOverrideAcrossPlanningAndExecution",
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeRebuildsRendererAfterRendererDataInvalidation",
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeReleasesPersistentRendererFeatureAcrossRendererInvalidationAndAssetRuntimeRelease",
    "MonoScriptRuntimeTest.ManagedRenderPipelineBridgeRebuildsPipelineAfterAssetInvalidation",
    "MonoScriptRuntimeTest.ManagedRenderPipelineAssetPlansFullscreenStagesFromPipelineStageSupport",
    "MonoScriptRuntimeTest.ManagedRendererFeatureConfiguresCameraFramePlanThroughPlanningContext",
    "ProjectScriptAssemblyTest.ProjectManagedBridgeRebuildsRendererAfterProjectRendererDataInvalidation",
    "ProjectScriptAssemblyTest.ProjectManagedBridgeReleasesProjectRendererCachesAcrossInvalidationAndAssetRuntimeRelease",
    "ProjectScriptAssemblyTest.ProjectManagedBridgeRebuildsPipelineAfterProjectAssetInvalidation"
)
$srpValidationFilter = [string]::Join(":", $srpValidationTests)

Push-Location $RepoRoot
try {
    if (-not $SkipBuild) {
        $buildTargets = @(
            "scripting_tests",
            "editor_windowing_phase1_tests"
        )
        if ($IncludeSmoke) {
            $buildTargets += "editor_ui_smoke_targets"
        }

        $buildArguments = @(
            "--build",
            $BuildDir,
            "--config",
            $Config,
            "--target"
        ) + $buildTargets

        Invoke-NativeStep `
            -Name "Build renderer phase regression targets ($Config)" `
            -FilePath "cmake" `
            -Arguments $buildArguments
    }

    Assert-PathExists -Path $scriptingExe -Label "scripting_tests.exe"
    Assert-PathExists -Path $windowingExe -Label "editor_windowing_phase1_tests.exe"

    if (-not $SkipCtestEnumerate) {
        Write-Host "ctest enumeration may still print *_NOT_BUILT placeholders for targets that were not built." `
            -ForegroundColor DarkGray
        Invoke-CtestEnumeration -BuildDir $BuildDir -Config $Config
    }

    Invoke-NativeStep `
        -Name "Run managed SRP validation batch (12 tests)" `
        -FilePath $scriptingExe `
        -Arguments @("--gtest_filter=$srpValidationFilter")

    Invoke-NativeStep `
        -Name "Run editor windowing phase1 tests" `
        -FilePath $windowingExe

    if ($IncludeSmoke) {
        Invoke-NativeStep `
            -Name "Run XCUI editor smoke" `
            -FilePath "ctest" `
            -Arguments @(
                "--test-dir", $BuildDir,
                "-C", $Config,
                "-R", "^xcui_editor_app_smoke$",
                "--output-on-failure"
            )
    }

    Write-Host "Renderer phase regression passed." -ForegroundColor Green
} finally {
    Pop-Location
}