diff --git a/app/Repositories/InvoiceRepository.php b/app/Repositories/InvoiceRepository.php
index 8cfc4218ca8d..8b26b876d779 100644
--- a/app/Repositories/InvoiceRepository.php
+++ b/app/Repositories/InvoiceRepository.php
@@ -13,12 +13,26 @@ class InvoiceRepository extends BaseRepository
 {
 
 
+    /**
+     * Gets the class name.
+     *
+     * @return     ::class  The class name.
+     */
     public function getClassName()
     {
         return Invoice::class;
     }
+
     
-	public function save($data, Invoice $invoice) : ?Invoice
+	/**
+     * Saves the invoices
+     *
+     * @param      array.                                        $data     The invoice data
+     * @param      InvoiceCalc|\App\Models\Invoice               $invoice  The invoice
+     *
+     * @return     Invoice|InvoiceCalc|\App\Models\Invoice|null  Returns the invoice object
+     */
+    public function save($data, Invoice $invoice) : ?Invoice
 	{
         $invoice->fill($data);
         
@@ -35,4 +49,25 @@ class InvoiceRepository extends BaseRepository
         return $invoice;
 	}
 
+
+    /**
+     * Mark the invoice as sent.
+     *
+     * @param      \App\Models\Invoice               $invoice  The invoice
+     *
+     * @return     Invoice|\App\Models\Invoice|null  Return the invoice object
+     */
+    public function markSent(Invoice $invoice) : ?Invoice
+    {
+
+        if($invoice->status_id >= Invoice::STATUS_SENT)
+            return;
+
+        $invoice->status_id = Invoice::STATUS_SENT;
+        $invoice->save();
+
+        return $invoice;
+
+    }
+
 }
\ No newline at end of file