MSGraphHelper

1.0

MSGraphHelper.psm1

function Get-RequiredModules {
    param (
        [string]$moduleName
    )

    # Check if the module is installed
    $moduleInstalled = Get-Module -ListAvailable -Name $moduleName
    if (-not $moduleInstalled) 
    {
        Write-Host "The required module '$moduleName' is not installed. Trying to install it." -ForegroundColor Yellow

        try {
            Install-Module -Name $moduleName -Force -Scope CurrentUser
            Write-Host "Successfully installed module '$moduleName'." -ForegroundColor Green
        } 
        
        catch {
            Write-Error "Could not install module '$moduleName' due to error: $_"
            return
        }
    }
    else {
        Write-Host "'$moduleName' is installed on this machine" -ForegroundColor Green
    }

    # Check if the module is imported
    $moduleImported = Get-Module -Name $moduleName
    if (-not $moduleImported) 
    {
        Write-Host "The required module '$moduleName' is not imported. Trying to import it." -ForegroundColor Yellow

        try {
            Import-Module -Name $moduleName
            Write-Host "Successfully imported module '$moduleName'."
        } 
        
        catch {
            Write-Error "Could not import module '$moduleName' due to error: $_"
        }
    }
    else {
        Write-Host "'$moduleName' is imported on this machine" -ForegroundColor Green
    }
}

function Get-AccessTokenMSAL-ApplicationPermission {
    param (
        [string]$clientId,
        [System.Security.SecureString]$clientSecret,
        [string]$tenantId
    )


    #Checking if required Modules are installed
    $RequiredModulesInstalled = Get-RequiredModules -moduleName "MSAL.PS"

    $scope = "https://graph.microsoft.com/.default"
    $tokenResult = Get-MsalToken -ClientId $clientId -ClientSecret $clientSecret -TenantId $tenantId -Scopes $scope
    
    return $tokenResult.AccessToken
    
}

function Get-AccessTokenMSAL-DelegatedPermissions {
    param (
        [string]$clientId,
        [string]$tenantId
    )

    $RequiredModulesInstalled = Get-RequiredModules -moduleName "MSAL.PS"
    $scope = "https://graph.microsoft.com/.default"
    $tokenResult = Get-MsalToken -ClientId $clientId -TenantId $tenantId -Scopes $scope -RedirectUri "http://localhost"

    return $tokenResult
}

function New-LocalSecret {
    param (
        [string]$UserName
    )
    $credential = Get-Credential -UserName $UserName -Message "Enter your client secret"
    $credentialsBasePath = $env:APPDATA+"\MSALCredentialStore\"
    if (!(Test-Path -Path $credentialsBasePath))
        {
        New-Item -Path $env:APPDATA -Name "MSALCredentialStore" -ItemType Directory | Out-Null
        }

    $credentialsExportFileName = "MSALCredentials.clixml"
    $credentialsPath = $credentialsBasePath + $credentialsExportFileName
    $credential | Export-Clixml -Path $credentialsPath -Force

    return $credentialsPath
}

function Get-LocalSecret {
    param (
        [string]$PathToCLIXML
    )
    # Retrieve the credential from the stored file
    $credential = Import-Clixml -Path $PathToCLIXML
    return $credential.Password
}

function Read-Calendar {
    param (
        [string]$accessToken,
        [string]$fromUser,    # User's email
        [DateTime]$startDate, # Start date for the calendar view
        [DateTime]$endDate    # End date for the calendar view
    )

    $graphApiEndpoint = "https://graph.microsoft.com/v1.0/users/$fromUser/calendarView?startDateTime=$($startDate.ToString('yyyy-MM-ddTHH:mm:ss'))&endDateTime=$($endDate.ToString('yyyy-MM-ddTHH:mm:ss'))&`$filter=showAs eq 'Oof'&`$select=subject,start,end,showAs"

    $headers = @{
        Authorization = "Bearer $accessToken"
        "Content-Type" = "application/json"
    }

    $response = Invoke-RestMethod -Uri $graphApiEndpoint -Method Get -Headers $headers
    return $response.value
}

function Send-Email {
    param (
        [string]$accessToken,
        [string]$recipientEmail,
        [string]$subject,
        [string]$body,
        [string]$fromUserIdOrUpn
    )

    $graphApiEndpoint = "https://graph.microsoft.com/v1.0/users/$fromUserIdOrUpn/sendMail"
    $headers = @{
        Authorization = "Bearer $accessToken"
        "Content-Type" = "application/json"
    }

    $emailData = @{
        message = @{
            subject = $subject
            body = @{
                contentType = "Text"
                content = $body
            }
            toRecipients = @(
                @{
                    emailAddress = @{
                        address = $recipientEmail
                    }
                }
            )
            from = @{
                emailAddress = @{
                    address = $fromUserIdOrUpn
                }
            }
        }
    }

    $emailJson = $emailData | ConvertTo-Json -Depth 100
    Invoke-RestMethod -Uri $graphApiEndpoint -Method Post -Headers $headers -Body $emailJson -ContentType "application/json"
}