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

# Enable TLS 1.2 for secure connections
[Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointProtocolType]::Tls12

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
    }
}

# Install DocumentFormat.OpenXml module
if (-not (Get-Module -ListAvailable -Name DocumentFormat.OpenXml)) {
    try {
        # Install NuGet package provider if not exists
        if (-not (Get-PackageProvider -Name NuGet)) {
            Install-PackageProvider -Name NuGet -Force
        }
        Install-Module DocumentFormat.OpenXml -Scope CurrentUser -Force -AllowClobber
        Write-Host "DocumentFormat.OpenXml module installed successfully" -ForegroundColor Green
    }
    catch {
        Write-Host "Failed to install DocumentFormat.OpenXml module: $($_.Exception.Message)" -ForegroundColor Red
        Write-Host "You may need to install the Open XML SDK manually." -ForegroundColor Yellow
        # Do not exit, as the application might still work if the assembly is in the GAC or a known path
    }
}
else {
    Write-Host "DocumentFormat.OpenXml 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:
    powershell.exe -STA -File .\MainForm.ps1
"@ -ForegroundColor Red
    exit 1
}

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

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