Get & validate custom field using standard API

Use mci_get_custom_field_id_from_objectref() to retrieve the custom
field's id.

Throw exceptions if
- the returned Id == 0 (invalid field)
- the field is not linked to the current project

Fixes #26541

api/soap/mc_project_api.php

@@ -637,16 +637,6 @@ function mci_project_custom_fields_validate( $p_project_id, &$p_custom_fields )
 		$t_custom_field_defs[$t_custom_field_id] = $t_def;
 	}
 
-	$fn_normalize_name = function( $p_name, $p_custom_field_defs ) {
-		foreach( $p_custom_field_defs as $t_custom_field_def ) {
-			if( strcasecmp( $t_custom_field_def['name'], $p_name ) == 0 ) {
-				return $t_custom_field_def['name'];
-			}
-		}
-
-		return $p_name;
-	};
-
 	$t_custom_field_values = array();
 	if( isset( $p_custom_fields ) ) {
 		if( !is_array( $p_custom_fields ) ) {
@@ -674,25 +664,25 @@ function mci_project_custom_fields_validate( $p_project_id, &$p_custom_fields )
 				);
 			}
 
-			$t_custom_field['field'] = ApiObjectFactory::objectToArray( $t_custom_field['field'] );
-
-			if( isset( $t_custom_field['field']['id'] ) ) {
-				$t_def = $t_custom_field_defs[(int)$t_custom_field['field']['id']];
+			$t_custom_field_id = mci_get_custom_field_id_from_objectref( (object)$t_custom_field['field'] );
+			if( $t_custom_field_id == 0 ) {
+				throw new ClientException(
+					'Invalid Custom Field '
+					# Output JSON stripped of quotes to help caller identify offending field
+					. str_replace( '"', '', json_encode( $t_custom_field['field'] ) ),
+					ERROR_CUSTOM_FIELD_NOT_FOUND
+				);
+			} else {
+				# Make sure the custom field is linked to the current project
+				if( !isset( $t_custom_field_defs[$t_custom_field_id] ) ) {
+					throw new ClientException(
+						"Custom Field Id '$t_custom_field_id' not found in Project '$p_project_id'.",
+						ERROR_CUSTOM_FIELD_NOT_FOUND
+					);
+				}
+				$t_def = $t_custom_field_defs[$t_custom_field_id];
 				$t_custom_field_values[$t_def['name']] = $t_custom_field['value'];
-				continue;
-			}
-
-			if( isset( $t_custom_field['field']['name'] ) ) {
-				$t_name = $fn_normalize_name( $t_custom_field['field']['name'], $t_custom_field_defs );
-				$t_custom_field_values[$t_name] = $t_custom_field['value'];
-				continue;
 			}
-
-			throw new ClientException(
-				'Custom field with no specified id or name.',
-				ERROR_EMPTY_FIELD,
-				"custom_field['field']['id']"
-			);
 		}
 	}