# WSL2 Environment Check Script
# This script checks WSL2 installation status on Windows

# Set error action
$ErrorActionPreference = 'Stop'

# Color definitions
$Red = [System.ConsoleColor]::Red
$Green = [System.ConsoleColor]::Green
$Yellow = [System.ConsoleColor]::Yellow

# Logging functions
function Write-Info {
    param([string]$Message)
    Write-Host '[INFO] ' -NoNewline -ForegroundColor $Green
    Write-Host $Message
}

function Write-Warn {
    param([string]$Message)
    Write-Host '[WARN] ' -NoNewline -ForegroundColor $Yellow
    Write-Host $Message
}

function Write-Error {
    param([string]$Message)
    Write-Host '[ERROR] ' -NoNewline -ForegroundColor $Red
    Write-Host $Message
}

function Wait-KeyPress {
    Write-Host "`nPress any key to exit..." -NoNewline
    $null = $Host.UI.RawUI.ReadKey('NoEcho,IncludeKeyDown')
    Write-Host ''
}

# Check administrator privileges
if (-NOT ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    Write-Warn 'Administrator privileges required'
    Write-Info 'Please right-click this script and select "Run as Administrator"'
    Wait-KeyPress
    exit 1
}

Write-Info "`nStarting WSL2 environment check...`n"

# Check Windows version
Write-Info 'Checking Windows version...'
$windowsVersion = (Get-WmiObject Win32_OperatingSystem).Caption
Write-Host "Windows Version: $windowsVersion"

# Check WSL installation status
Write-Info 'Checking WSL installation...'
try {
    $wslVersion = wsl --version
    Write-Info 'WSL is installed'
    Write-Host "`n$wslVersion`n"
} catch {
    Write-Error 'WSL is not installed'
    Write-Info 'Please visit https://aka.ms/wsl to install WSL'
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

# Check WSL2 status
Write-Info 'Checking WSL2 status...'
try {
    $wslList = wsl -l -v
    if ($wslList -match '2') {
        Write-Info 'WSL2 is enabled'
    } else {
        Write-Warn 'WSL2 is not enabled'
        Write-Info 'WSL distribution list:'
        Write-Host "`n$wslList`n"
        Write-Info 'Please run the following command to enable WSL2:'
        Write-Host 'wsl --set-default-version 2'
        Wait-KeyPress
        exit 1
    }
} catch {
    Write-Error "Failed to get WSL status: $($_.Exception.Message)"
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

# Check Debian installation status
Write-Info 'Checking Debian installation...'
try {
    wsl -d Debian echo 'Debian is installed' | Out-Null
    Write-Info 'Debian is installed'
} catch {
    Write-Warn 'Debian is not installed'
    Write-Info 'Please run the following command to install Debian:'
    Write-Host 'wsl --install -d Debian'
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

# Check virtualization status
Write-Info 'Checking virtualization status...'
try {
    $systemInfo = systeminfo
    if ($systemInfo -match 'Virtual Ethernet Adapter' -or $systemInfo -match 'hypervisor has been detected') {
        Write-Info 'Virtualization is enabled'
    } else {
        Write-Error 'Virtualization is not enabled'
        Write-Info 'Please enable virtualization (Intel VT-x or AMD-V) in BIOS'
        Wait-KeyPress
        exit 1
    }
} catch {
    Write-Error "Failed to check virtualization status: $($_.Exception.Message)"
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

# Check Windows features
Write-Info 'Checking Windows features...'

# Check Linux subsystem
try {
    $wslFeature = Get-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux
    if ($wslFeature.State -eq 'Enabled') {
        Write-Info 'Linux subsystem is enabled'
    } else {
        Write-Warn 'Linux subsystem is not enabled'
        Write-Info 'Please run the following command to enable Linux subsystem:'
        Write-Host 'dism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestart'
        Wait-KeyPress
        exit 1
    }
} catch {
    Write-Error "Failed to check Linux subsystem status: $($_.Exception.Message)"
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

# Check virtual machine platform
try {
    $vmPlatform = Get-WindowsOptionalFeature -Online -FeatureName VirtualMachinePlatform
    if ($vmPlatform.State -eq 'Enabled') {
        Write-Info 'Virtual Machine Platform is enabled'
    } else {
        Write-Warn 'Virtual Machine Platform is not enabled'
        Write-Info 'Please run the following command to enable Virtual Machine Platform:'
        Write-Host 'dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart'
        Wait-KeyPress
        exit 1
    }
} catch {
    Write-Error "Failed to check Virtual Machine Platform status: $($_.Exception.Message)"
    Wait-KeyPress
    exit 1
} finally {
    # Clear errors
    $error.clear()
}

Write-Host "`n============================================"
Write-Host "            Check Complete!                 "
Write-Host "============================================"
Write-Host "`nYour WSL2 environment is ready:`n"
Write-Info '1. Windows version is compatible'
Write-Info '2. WSL2 is installed and enabled'
Write-Info '3. Debian distribution is installed'
Write-Info '4. Virtualization is enabled'
Write-Info '5. Required Windows features are enabled'
Write-Info 'You can now start using WSL2!'
Write-Host "============================================"

# Wait for user input before exit
Wait-KeyPress