install-wsl.ps1

# WSL2 Installation Helper for Windows
# Run this from Windows PowerShell to set up WSL2 and configure .wslconfig

#Requires -RunAsAdministrator

param(
    [switch]$Force,
    [switch]$SkipWSLInstall,
    [switch]$SkipDistro
)

$ErrorActionPreference = "Stop"

function Write-ColorOutput {
    param(
        [string]$Message,
        [string]$Color = "White"
    )
    Write-Host $Message -ForegroundColor $Color
}

function Write-Section {
    param([string]$Title)
    Write-Host ""
    Write-Host "═══════════════════════════════════════════════════════════════" -ForegroundColor Cyan
    Write-Host "  $Title" -ForegroundColor Cyan
    Write-Host "═══════════════════════════════════════════════════════════════" -ForegroundColor Cyan
    Write-Host ""
}

function Test-WSLInstalled {
    try {
        $null = wsl --status 2>&1
        return $true
    }
    catch {
        return $false
    }
}

function Enable-WSLFeatures {
    Write-Section "Enabling WSL Features"

    Write-ColorOutput "Enabling WSL feature..." -ForegroundColor Yellow
    dism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestart

    Write-ColorOutput "Enabling Virtual Machine Platform..." -ForegroundColor Yellow
    dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart

    Write-ColorOutput "WSL features enabled successfully!" -ForegroundColor Green
}

function Set-WSLDefaultVersion {
    Write-Section "Setting WSL 2 as Default"

    wsl --set-default-version 2
    Write-ColorOutput "WSL 2 set as default version." -ForegroundColor Green
}

function Install-Ubuntu24 {
    Write-Section "Installing Ubuntu 24.04 LTS"

    Write-ColorOutput "Checking for Ubuntu 24.04 installation..." -ForegroundColor Yellow

    $wslList = wsl --list --verbose 2>&1
    if ($wslList -match "Ubuntu-24\.04") {
        Write-ColorOutput "Ubuntu 24.04 is already installed." -ForegroundColor Green
        return
    }

    Write-ColorOutput "Installing Ubuntu 24.04 LTS..." -ForegroundColor Yellow
    Write-ColorOutput "This will open the Microsoft Store. Please complete the installation there." -ForegroundColor White

    Start-Process "ms-windows-store://pdp/?productid=9PN20MSR04DW"

    Write-ColorOutput "Press Enter after you've completed the Ubuntu installation in the Store..." -ForegroundColor Yellow
    Read-Host
}

function Copy-WSLConfig {
    Write-Section "Configuring .wslconfig"

    $scriptDir = Split-Path -Parent $PSScriptRoot
    $wslconfigSource = Join-Path $scriptDir "config\wslconfig"
    $wslconfigDest = "$env:USERPROFILE\.wslconfig"

    if ((Test-Path $wslconfigDest) -and !$Force) {
        Write-ColorOutput ".wslconfig already exists at $wslconfigDest" -ForegroundColor Yellow
        $response = Read-Host "Overwrite? (y/N)"
        if ($response -ne 'y' -and $response -ne 'Y') {
            Write-ColorOutput "Skipping .wslconfig configuration." -ForegroundColor Yellow
            return
        }
    }

    if (Test-Path $wslconfigSource) {
        Copy-Item $wslconfigSource $wslconfigDest -Force
        Write-ColorOutput ".wslconfig installed to $wslconfigDest" -ForegroundColor Green
        Write-ColorOutput "Restart WSL for changes to take effect: wsl --shutdown" -ForegroundColor Yellow
    }
    else {
        Write-ColorOutput "Warning: config/wslconfig not found at $wslconfigSource" -ForegroundColor Red
    }
}

function Get-SystemMemory {
    $cs = Get-CimInstance -ClassName Win32_ComputerSystem
    return [math]::Round($cs.TotalPhysicalMemory / 1GB)
}

function Get-SystemProcessors {
    return [Environment]::ProcessorCount
}

function Optimize-WSLConfig {
    Write-Section "Optimizing .wslconfig for Your System"

    $memoryGB = Get-SystemMemory
    $processors = Get-SystemProcessors

    Write-ColorOutput "System Memory: $memoryGB GB" -ForegroundColor Cyan
    Write-ColorOutput "Logical Processors: $processors" -ForegroundColor Cyan

    # Calculate optimal settings
    $wslMemory = if ($memoryGB -ge 32) { "16GB" }
                 elseif ($memoryGB -ge 16) { "12GB" }
                 elseif ($memoryGB -ge 8) { "6GB" }
                 else { "4GB" }

    $wslProcessors = if ($processors -ge 16) { 8 }
                     elseif ($processors -ge 8) { 4 }
                     else { 2 }

    $wslSwap = if ($memoryGB -ge 32) { "4GB" }
               elseif ($memoryGB -ge 16) { "3GB" }
               else { "2GB" }

    Write-ColorOutput "Recommended settings:" -ForegroundColor Yellow
    Write-ColorOutput "  memory: $wslMemory" -ForegroundColor White
    Write-ColorOutput "  processors: $wslProcessors" -ForegroundColor White
    Write-ColorOutput "  swap: $wslSwap" -ForegroundColor White

    $scriptDir = Split-Path -Parent $PSScriptRoot
    $wslconfigDest = "$env:USERPROFILE\.wslconfig"

    # Create optimized config
    $configContent = @"
[wsl2]
memory=$wslMemory
processors=$wslProcessors
swap=$wslSwap
localhostForwarding=true

[experimental]
autoMemoryReclaim=gradual
sparseVhd=true
"@

    Set-Content -Path $wslconfigDest -Value $configContent -Force
    Write-ColorOutput "Optimized .wslconfig created!" -ForegroundColor Green
}

function Show-CompletionMessage {
    Write-Section "Setup Complete!"

    Write-ColorOutput "Next steps:" -ForegroundColor Green
    Write-Host "1. Restart WSL to apply .wslconfig changes:"
    Write-Host "   wsl --shutdown"
    Write-Host "   wsl"
    Write-Host ""
    Write-Host "2. From inside WSL2 Ubuntu, navigate to the project and run:"
    Write-Host "   cd ~/wsl2-migration  # or wherever you cloned it"
    Write-Host "   ./bootstrap.sh"
    Write-Host ""
}

# Main execution
function Main {
    Write-Host ""
    Write-Host "╔═══════════════════════════════════════════════════════════════╗" -ForegroundColor Cyan
    Write-Host "║                                                               ║" -ForegroundColor Cyan
    Write-Host "║   WSL2 Installation Helper (Windows Side)                    ║" -ForegroundColor Cyan
    Write-Host "║                                                               ║" -ForegroundColor Cyan
    Write-Host "╚═══════════════════════════════════════════════════════════════╝" -ForegroundColor Cyan
    Write-Host ""

    # Check if running as Administrator
    $isAdmin = ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)
    if (!$isAdmin) {
        Write-ColorOutput "This script requires Administrator privileges." -ForegroundColor Red
        Write-ColorOutput "Please right-click PowerShell and select 'Run as Administrator'." -ForegroundColor Yellow
        exit 1
    }

    # Enable WSL features if not already installed
    if (!$SkipWSLInstall) {
        if (Test-WSLInstalled) {
            Write-ColorOutput "WSL is already installed." -ForegroundColor Green
        }
        else {
            Enable-WSLFeatures
            Write-ColorOutput "Please restart your computer, then run this script again with -SkipWSLInstall" -ForegroundColor Yellow
            exit 0
        fi

        Set-WSLDefaultVersion
    }

    # Install Ubuntu distro
    if (!$SkipDistro) {
        Install-Ubuntu24
    }

    # Configure .wslconfig
    if ($Force) {
        Optimize-WSLConfig
    }
    else {
        Copy-WSLConfig
    }

    Show-CompletionMessage
}

Main