# Function to query the registry
function Get-RegistryValue {
	param (
		[string]$path,
		[string]$value
	)

	try {
		$result = Get-ItemProperty -Path $path -ErrorAction Stop
		return $result.$value
	} catch {
		return $null
	}
}

Write-Host "Searching for Steam installation..." -ForegroundColor White

# Get Steam installation path from registry
$steam_dir = Get-RegistryValue "HKLM:\SOFTWARE\Valve\Steam" "InstallPath"

if (-not $steam_dir) {
	$steam_dir = Get-RegistryValue "HKLM:\SOFTWARE\WOW6432Node\Valve\Steam" "InstallPath"
}

# Fallback to searching for Steam.exe on all drives
if (-not $steam_dir) {
	Write-Host "No registry key found. Searching for Steam executable on all drives..." -ForegroundColor Yellow

	# Get all filesystem drives
	$drives = Get-PSDrive -PSProvider FileSystem | Where-Object { $_.Name -match '^[A-Z]$' }

	foreach ($drive in $drives) {
		# Properly format drive path, avoid additional quotes
		$drive_letter = $drive.Name
		$steam_exe = Get-ChildItem -Path "$($drive_letter):\" -Recurse -Include "Steam.exe" -ErrorAction SilentlyContinue | Select-Object -First 1

		if ($steam_exe) {
			$steam_dir = Split-Path $steam_exe.FullName -Parent
			break
		}
	}
}

if (-not $steam_dir) {
	Write-Host "Steam installation path not found" -ForegroundColor Red
	Read-Host "Press Enter to exit"
	exit
}

Write-Host "Steam installation path: $steam_dir" -ForegroundColor Cyan

# Initialize Garry's Mod directory as null
$gmod_dir = $null

# Check for Garry's Mod installation in the primary Steam library
$gmod_check_path = Join-Path $steam_dir "steamapps\appmanifest_4000.acf"
if (Test-Path $gmod_check_path) {
	$gmod_dir = Join-Path $steam_dir "steamapps\common\GarrysMod"
}

# Check for Garry's Mod in additional Steam library folders if not found in the primary
if (-not $gmod_dir) {
	$library_folders_path = Join-Path $steam_dir "steamapps\libraryfolders.vdf"

	if (Test-Path $library_folders_path) {
		$library_folders = (Get-Content $library_folders_path) -join "`n"
		$library_paths = $library_folders -split '(?=\s*"\d+"\s*{)' # Split by each library entry

		foreach ($library in $library_paths) {
			# Extract the library path from the line that contains "path"
			if ($library -match '"path"\s*"\s*(.+)\s*"') {
				# Clean the extracted path to remove extra backslashes or quotes
				$library_path = $matches[1] -replace "\\{2,}", "\" # Replace any multiple backslashes with a single backslash
				$library_path = $library_path.Trim('"')			 # Remove any surrounding quotes
			}

			# If "4000" (Garry's Mod ID) is found, set the GMod directory
			if ($library -match '"4000"') {
				$gmod_dir = Join-Path $library_path "steamapps\common\GarrysMod"
				break
			}
		}
	}
}

if (-not $gmod_dir) {
	Write-Host "GMod installation path not found" -ForegroundColor Red
	Read-Host "Press Enter to exit"
	exit
}

Write-Host "GMod installation path: $gmod_dir" -ForegroundColor Cyan

# Confirm Garry's Mod installation path
$GMODPath = Join-Path $gmod_dir "garrysmod"
Write-Host "Do you want to install in this path? It will completely wipe the previous Beatrun install if you had one!" -ForegroundColor Yellow
$GMODConfirmation = Read-Host "(y/n)"

if ($GMODConfirmation -eq "y" -or $GMODConfirmation -eq "Y") {
	# Define paths
	$TempPath = Join-Path $GMODPath "temp"
	$ZIPPath = Join-Path $TempPath "beatrun.zip"
	$FolderMainPath = Join-Path $TempPath "beatrun-main"
	$FolderPath = Join-Path $TempPath "beatrun"
	$AddonPath = Join-Path $FolderPath "beatrun"
	$NewAddonPath = Join-Path $GMODPath "addons\beatrun"

	# Ensure the temporary directory exists
	if (-not (Test-Path -Path $TempPath)) {
		New-Item -ItemType Directory -Path $TempPath -Force | Out-Null
	}

	# Download Beatrun zip
	Write-Host "Downloading the Beatrun archive..." -ForegroundColor White
	try {
		(New-Object Net.WebClient).DownloadFile("https://github.com/JonnyBro/beatrun/archive/refs/heads/main.zip", $ZIPPath)
		Write-Host "Download successful!" -ForegroundColor Green
	} catch {
		Write-Host "Error: Unable to download Beatrun. Please check your internet connection or URL." -ForegroundColor Red
		exit
	}

	# Unzip the archive
	Write-Host "Unpacking the archive..." -ForegroundColor White
	try {
		Expand-Archive -Path $ZIPPath -DestinationPath $TempPath -Force
		Write-Host "Unpacking successful!" -ForegroundColor Green
	} catch {
		Write-Host "Error: Failed to unpack the Beatrun archive." -ForegroundColor Red
		exit
	}

	# Rename and prepare files
	if (Test-Path $FolderMainPath) {
		Rename-Item -Path $FolderMainPath -NewName $FolderPath
	} else {
		Write-Host "Error: Unpacked folder not found." -ForegroundColor Red
		exit
	}

	# Remove the downloaded zip file
	Remove-Item -Path $ZIPPath -Force

	# Confirm the addon directory exists
	if (Test-Path $NewAddonPath) {
		Write-Host "Previous Beatrun installation found. Removing old installation..." -ForegroundColor White
		Remove-Item -Path $NewAddonPath -Recurse -Force
	}

	# Move the new Beatrun addon
	Write-Host "Installing Beatrun..." -ForegroundColor White
	Move-Item -Path $AddonPath -Destination $NewAddonPath -Force

	# Clean up temporary files
	Remove-Item -Path $TempPath -Recurse -Force
	Write-Host "Beatrun has been installed successfully!" -ForegroundColor Green
}