[CmdletBinding()]
param(
    [string]$BuildDir = "build",
    [string]$Config = "Debug",
    [string]$RepoRoot = (Resolve-Path (Join-Path $PSScriptRoot "..")).Path,
    [int]$SmokeSeconds = 5,
    [switch]$SkipBuild,
    [switch]$SkipSmoke,
    [switch]$CleanBuild
)

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

function Invoke-Step {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Label,
        [Parameter(Mandatory = $true)]
        [scriptblock]$Action
    )

    Write-Host "==> $Label"
    & $Action
}

function Invoke-Native {
    param(
        [Parameter(Mandatory = $true)]
        [string]$FilePath,
        [Parameter()]
        [string[]]$Arguments = @(),
        [string]$WorkingDirectory = $RepoRoot
    )

    Push-Location $WorkingDirectory
    try {
        & $FilePath @Arguments
        if ($LASTEXITCODE -ne 0) {
            throw ("Command failed with exit code {0}: {1} {2}" -f $LASTEXITCODE, $FilePath, ($Arguments -join ' '))
        }
    }
    finally {
        Pop-Location
    }
}

function Get-ExePath {
    param(
        [Parameter(Mandatory = $true)]
        [string[]]$Parts
    )

    $path = $BuildDir
    foreach ($part in $Parts) {
        $path = Join-Path $path $part
    }

    $resolved = if ([System.IO.Path]::IsPathRooted($path)) {
        $path
    }
    else {
        Join-Path $RepoRoot $path
    }
    if (-not (Test-Path $resolved)) {
        throw "Expected executable does not exist: $resolved"
    }

    return $resolved
}

$RepoRoot = [System.IO.Path]::GetFullPath($RepoRoot)
$BuildDir = if ([System.IO.Path]::IsPathRooted($BuildDir)) {
    [System.IO.Path]::GetFullPath($BuildDir)
}
else {
    [System.IO.Path]::GetFullPath((Join-Path $RepoRoot $BuildDir))
}

$msbuildArguments = @(
    "--", "/m:1",
    "/p:UseMultiToolTask=false",
    "/p:CL_MPCount=1"
)

if (-not $SkipBuild) {
    if ($CleanBuild) {
        Invoke-Step "Clean rebuild XCEngine" {
            Invoke-Native -FilePath "cmake" -Arguments (@(
                "--build", $BuildDir,
                "--config", $Config,
                "--target", "XCEngine",
                "--clean-first"
            ) + $msbuildArguments)
        }
    }

    Invoke-Step "Build rendering regression targets" {
        Invoke-Native -FilePath "cmake" -Arguments (@(
            "--build", $BuildDir,
            "--config", $Config,
            "--target", "rendering_phase_regression_build"
        ) + $msbuildArguments)
    }
}

$executables = @(
    (Get-ExePath -Parts @("tests", "Rendering", "unit", $Config, "rendering_unit_tests.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "textured_quad_scene", $Config, "rendering_integration_textured_quad_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "backpack_scene", $Config, "rendering_integration_backpack_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "backpack_lit_scene", $Config, "rendering_integration_backpack_lit_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "camera_stack_scene", $Config, "rendering_integration_camera_stack_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "transparent_material_scene", $Config, "rendering_integration_transparent_material_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "cull_material_scene", $Config, "rendering_integration_cull_material_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "depth_sort_scene", $Config, "rendering_integration_depth_sort_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "material_state_scene", $Config, "rendering_integration_material_state_scene.exe")),
    (Get-ExePath -Parts @("tests", "Rendering", "integration", "offscreen_scene", $Config, "rendering_integration_offscreen_scene.exe")),
    (Get-ExePath -Parts @("tests", "Editor", $Config, "editor_tests.exe"))
)

foreach ($executable in $executables) {
    $label = [System.IO.Path]::GetFileName($executable)
    $workingDirectory = Split-Path -Parent $executable
    Invoke-Step "Run $label" {
        Invoke-Native -FilePath $executable -WorkingDirectory $workingDirectory
    }
}

if (-not $SkipSmoke) {
    $editorExe = Join-Path $RepoRoot "editor\bin\$Config\XCEngine.exe"
    if (-not (Test-Path $editorExe)) {
        throw "Expected editor executable does not exist: $editorExe"
    }

    Invoke-Step "Smoke launch XCEditor ($SmokeSeconds seconds)" {
        $process = Start-Process -FilePath $editorExe -WorkingDirectory $RepoRoot -PassThru
        try {
            Start-Sleep -Seconds $SmokeSeconds
            if ($process.HasExited) {
                if ($process.ExitCode -ne 0) {
                    throw "XCEditor exited early with code $($process.ExitCode)"
                }
            }
            else {
                Stop-Process -Id $process.Id -Force
            }
        }
        finally {
            if (-not $process.HasExited) {
                Stop-Process -Id $process.Id -Force -ErrorAction SilentlyContinue
            }
        }
    }
}

Write-Host "Renderer phase regression passed."