#Required running with elevated right.
if (-not([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")) {
   Write-Warning "You need to have Administrator rights to run this script!`nPlease re-run this script as an Administrator in an elevated powershell prompt!"
   break
}

Write-host "`nPreparing the system to running the script..."

#Configure Execution Policy
if ((Get-ExecutionPolicy) -notmatch "RemoteSigned") {
     Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope LocalMachine -Force
}

#Update the NuGet Provider if needed.
$nuGetPath = "C:\Program Files\PackageManagement\ProviderAssemblies\nuget\*\Microsoft.PackageManagement.NuGetProvider.dll"
$testPath = Test-Path -Path $nuGetPath
if ($testPath -match 'false') {
    Write-Host "`nInstalling NuGet Provider..."
    Install-PackageProvider -Name NuGet -Force | Out-Null
}

#Update the PowerShellGet if needed.
$PSGetCurrentVersion = (Get-PackageProvider -Name 'PowerShellGet').Version
$PSGetLatestVersion = (Find-Module PowerShellGet).Version
if ($PSGetCurrentVersion -lt $PSGetLatestVersion) {
    Write-Host "`nUpdating PowerShellGet Module from $PSGetCurrentVersion to $PSGetLatestVersion..."
    Install-Module -Name 'PowerShellGet' -Force
}


#We're installing from the PowerShell Gallery so make sure that it's trusted.
$InstallationPolicy = (Get-PSRepository -Name PSGallery).InstallationPolicy
if ($InstallationPolicy -match "Untrusted") {
   Write-host "`nConfiguring the PowerShell Gallery Repository..."
   Set-PSRepository -Name "PSGallery" -InstallationPolicy Trusted
}

$graphCurrentVersion = (Get-InstalledModule Microsoft.Graph -ErrorAction SilentlyContinue).Version
$graphLatestVerison = (Find-Module Microsoft.Graph).Version

#Checking the Microsoft Graph module for installation
if($graphCurrentVersion -eq $null){
    Write-host "`nInstalling Microsoft Graph module version $graphLatestVerison..."
    Install-Module Microsoft.Graph -Scope CurrentUser -AllowClobber -Force
    Write-host "Microsoft Graph module version $graphLatestVerison is installed in the machine successfully" -ForegroundColor Green
}else {
    Write-Host "`nThe Microsoft Graph module version $graphCurrentVersion has been installed on this computer." -ForegroundColor Green
}

#Update to Microsoft Graph PowerShell SDK v2
if (($currentVersion -ne $null) -and ($graphCurrentVersion -lt $graphLatestVerison)) {
    Write-host "`nUpdating Microsoft Graph module from $graphCurrentVersion to $graphLatestVerison..."
    Update-Module Microsoft.Graph -Force
}

#Checking the Microsoft Graph Beta module for installation
$MsGraphBetaModule =  Get-Module Microsoft.Graph.Beta -ListAvailable
if($MsGraphBetaModule -eq $null){ 
    Write-host "`nInstalling Microsoft Graph Beta module ..."
    Install-Module Microsoft.Graph.Beta -Scope CurrentUser -AllowClobber -Force
    Write-host "Microsoft Graph Beta module is installed in the machine successfully" -ForegroundColor Green
}else {
    Write-Host "The Microsoft Graph Beta module has been installed on this computer." -ForegroundColor Green
}

Clear-Host