param(
    [string]$Version = "",
    [string]$BuildDir = "build\win",
    [string]$StagingDir = "dist\win",
    [string]$WintunVersion = "0.14.1",
    [switch]$Sign,
    [string]$SignCert = ""
)

$ErrorActionPreference = "Stop"

# Color output functions
function Write-Info { Write-Host $args -ForegroundColor Cyan }
function Write-Success { Write-Host $args -ForegroundColor Green }
function Write-Error { Write-Host $args -ForegroundColor Red }

try {
    Write-Info "=== DragonMoonlight Windows Installer Build ==="
    
    # Determine version
    if ([string]::IsNullOrEmpty($Version)) {
        Write-Info "Version not provided, attempting git describe..."
        try {
            $Version = git describe --tags --abbrev=0 2>$null
            if ([string]::IsNullOrEmpty($Version)) {
                $Version = "0.1.0"
            }
        } catch {
            $Version = "0.1.0"
        }
    }
    Write-Success "Building DragonMoonlight version: $Version"
    
    # Check prerequisites
    Write-Info "Checking prerequisites..."
    $prerequisites = @("cmake", "cargo", "iscc", "windeployqt")
    foreach ($tool in $prerequisites) {
        try {
            if ($tool -eq "iscc") {
                $result = Get-Command "iscc.exe" -ErrorAction Stop
            } elseif ($tool -eq "windeployqt") {
                $result = Get-Command "windeployqt.exe" -ErrorAction Stop
            } else {
                $result = Get-Command $tool -ErrorAction Stop
            }
            Write-Success "✓ $tool found"
        } catch {
            Write-Error "✗ $tool not found. Please install it before proceeding."
            throw "Missing prerequisite: $tool"
        }
    }
    
    # Build boringtun
    Write-Info "Building boringtun..."
    & pwsh scripts\build-boringtun-win.ps1
    if ($LASTEXITCODE -ne 0) {
        throw "boringtun build failed"
    }
    Write-Success "boringtun built successfully"
    
    # CMake configure
    Write-Info "Running CMake configure..."
    cmake -B $BuildDir -A x64 -DCMAKE_BUILD_TYPE=Release
    if ($LASTEXITCODE -ne 0) {
        throw "CMake configure failed"
    }
    Write-Success "CMake configure completed"
    
    # CMake build
    Write-Info "Building with CMake..."
    cmake --build $BuildDir --config Release
    if ($LASTEXITCODE -ne 0) {
        throw "CMake build failed"
    }
    Write-Success "CMake build completed"
    
    # Create staging directory and copy executable
    Write-Info "Staging release files..."
    if (-not (Test-Path $StagingDir)) {
        New-Item -ItemType Directory -Path $StagingDir -Force | Out-Null
    }
    
    $exePath = Join-Path $BuildDir "Release\DragonMoonlight.exe"
    if (-not (Test-Path $exePath)) {
        throw "DragonMoonlight.exe not found at $exePath"
    }
    
    Copy-Item -Path $exePath -Destination $StagingDir -Force
    Write-Success "Copied DragonMoonlight.exe to $StagingDir"
    
    # Run windeployqt
    Write-Info "Running windeployqt..."
    $stagedExe = Join-Path $StagingDir "DragonMoonlight.exe"
    windeployqt --release --qmldir app $stagedExe
    if ($LASTEXITCODE -ne 0) {
        throw "windeployqt failed"
    }
    Write-Success "windeployqt completed"
    
    # Download wintun.dll
    Write-Info "Downloading Wintun..."
    $wintunUrl = "https://www.wintun.net/builds/wintun-$WintunVersion.zip"
    $tempDir = Join-Path $env:TEMP "wintun_build"
    if (-not (Test-Path $tempDir)) {
        New-Item -ItemType Directory -Path $tempDir -Force | Out-Null
    }
    
    $wintunZip = Join-Path $tempDir "wintun-$WintunVersion.zip"
    
    try {
        Write-Info "Downloading from $wintunUrl..."
        Invoke-WebRequest -Uri $wintunUrl -OutFile $wintunZip -UseBasicParsing
        
        Write-Info "Extracting wintun.dll..."
        Expand-Archive -Path $wintunZip -DestinationPath $tempDir -Force
        
        $wintunDll = Join-Path $tempDir "wintun\bin\amd64\wintun.dll"
        if (-not (Test-Path $wintunDll)) {
            throw "wintun.dll not found in extracted archive"
        }
        
        # Verify wintun.dll size sanity check (x64 is ~50-80 KB)
        $actualSize = (Get-Item $wintunDll).Length
        if ($actualSize -lt 30000 -or $actualSize -gt 200000) {
            throw "wintun.dll size check failed ($actualSize bytes) — download may be corrupt or tampered"
        }
        Write-Info "wintun.dll verified ($actualSize bytes)"
        
        Copy-Item -Path $wintunDll -Destination $StagingDir -Force
        Write-Success "Wintun.dll extracted and copied to $StagingDir"
    } finally {
        if (Test-Path $wintunZip) {
            Remove-Item -Path $wintunZip -Force
        }
    }
    
    # Run Inno Setup
    Write-Info "Building installer with Inno Setup..."
    
    $issArgs = @("/DMyAppVersion=$Version", "scripts\DragonMoonlight.iss")
    
    if ($Sign -or -not [string]::IsNullOrEmpty($SignCert)) {
        $cert = $SignCert
        if ([string]::IsNullOrEmpty($cert) -and -not [string]::IsNullOrEmpty($env:SIGNTOOL_CERT)) {
            $cert = $env:SIGNTOOL_CERT
        }
        
        if (-not [string]::IsNullOrEmpty($cert)) {
            Write-Info "Code signing enabled with certificate: $cert"
            $env:SIGNTOOL_CERT = $cert
        }
    }
    
    iscc @issArgs
    if ($LASTEXITCODE -ne 0) {
        throw "Inno Setup build failed"
    }
    Write-Success "Inno Setup build completed"
    
    # Report results
    $outputExe = Join-Path "dist" "DragonMoonlight-$Version-Setup.exe"
    if (Test-Path $outputExe) {
        Write-Success "Installer created: $outputExe"
        
        $sha256 = (Get-FileHash -Path $outputExe -Algorithm SHA256).Hash
        Write-Success "SHA256: $sha256"
        
        Write-Info "Installer build successful!"
    } else {
        throw "Installer file not found at expected location: $outputExe"
    }
}
catch {
    Write-Error "Build failed: $_"
    exit 1
}
finally {
    # Clean up temporary files
    $tempDir = Join-Path $env:TEMP "wintun_build"
    if (Test-Path $tempDir) {
        Remove-Item -Path $tempDir -Recurse -Force -ErrorAction SilentlyContinue
    }
}