#Requires -RunAsAdministrator
<#
.SYNOPSIS
Installs prerequisites for SharePoint XLS Converter application
#>

# Enable TLS 1.2 for secure connections
[Net.ServicePointManager]::SecurityProtocol = [enum]::Parse([Net.SecurityProtocolType], "Tls12")

# Verify .NET Framework 4.6+ is installed
if (-not (Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\' | Get-ItemPropertyValue -Name Release | ForEach-Object { $_ -ge 394802 })) {
    Write-Host "ERROR: Requires .NET Framework 4.6.2 or newer!" -ForegroundColor Red
    Write-Host "Download from: https://dotnet.microsoft.com/download/dotnet-framework" -ForegroundColor Yellow
    exit 1
}

Write-Host "Installing required modules..." -ForegroundColor Cyan

# Install Microsoft.Graph modules
$graphModules = @(
    "Microsoft.Graph.Sites",
    "Microsoft.Graph.Files",
    "Microsoft.Graph.Authentication"
)

foreach ($module in $graphModules) {
    if (-not (Get-Module -ListAvailable -Name $module)) {
        try {
            Install-Module $module -Scope CurrentUser -Force -AllowClobber
            Write-Host "$module module installed successfully" -ForegroundColor Green
        }
        catch {
            Write-Host "Failed to install ${module}: $($_.Exception.Message)" -ForegroundColor Red
            exit 1
        }
    }
    else {
        Write-Host "$module module is already installed" -ForegroundColor Yellow
    }
}


# Check for Excel installation
try {
    $excelCheck = New-Object -ComObject Excel.Application -ErrorAction Stop
    $excelCheck.Quit()
    [System.Runtime.Interopservices.Marshal]::ReleaseComObject($excelCheck) | Out-Null
    Write-Host "Microsoft Excel is installed" -ForegroundColor Green
}
catch {
    Write-Host @"
    Microsoft Excel not found! The conversion feature requires:
    1. Microsoft Excel 2013 or newer
    2. PowerShell must run in STA mode
    Run the main script like this:
    pwsh -STA -File .\MainForm.ps1
"@ -ForegroundColor Red
    exit 1
}

Write-Host @"
Installation complete! Run the main application with:
pwsh -STA -File .\MainForm.ps1

Note: First run might take longer while modules load
"@ -ForegroundColor Green