COMCL-333: Fix bug with empty target contact for file upload activities

CRM/Civicase/Hook/ValidateForm/RemoveEmptyTargetContactFromActivity.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * CiviCRM errors out if an empty string is sent for target contact id and to solve this we
+ * remove the target_contact_id param for activity form if its value is empty string.
+ */
+class CRM_Civicase_Hook_ValidateForm_RemoveEmptyTargetContactFromActivity {
+
+  public function run(string $formName, array &$fields, array &$files, CRM_Core_Form $form, array &$errors) {
+    if (!$this->shouldRun($formName)) {
+      return FALSE;
+    }
+
+    $submittedData = &$form->controller->container();
+    if (is_array($submittedData)
+      && isset($submittedData['values']['Activity']['target_contact_id'])
+      && $submittedData['values']['Activity']['target_contact_id'] === ''
+    ) {
+      unset($submittedData['values']['Activity']['target_contact_id']);
+    }
+  }
+
+  private function shouldRun(string $formName) {
+    return $formName === 'CRM_Case_Form_Activity';
+  }
+}

civicase.php

@@ -310,6 +310,7 @@ function civicase_civicrm_validateForm($formName, &$fields, &$files, &$form, &$e
     new CRM_Civicase_Hook_ValidateForm_SaveActivityDraft(),
     new CRM_Civicase_Hook_ValidateForm_SaveCaseTypeCategory(),
     new CRM_Civicase_Hook_ValidateForm_SendBulkEmail(),
+    new CRM_Civicase_Hook_ValidateForm_RemoveEmptyTargetContactFromActivity(),
   ];
 
   foreach ($hooks as $hook) {