New file_can_view_or_download() function

file_can_view_bug_attachments() and file_can_download_bug_attachments()
have nearly identical code, the only difference being the names of the
configs.

Adding a new internal File API function to avoid code duplication.

Fixes #27299

core/file_api.php

@@ -206,30 +206,72 @@ function file_bug_has_attachments( $p_bug_id ) {
 	}
 }
 
+/**
+ * Check if the current user can view or download attachments.
+ *
+ * Generic call used by
+ * - {@see file_can_view_bug_attachments()}
+ * - {@see file_can_view_bugnote_attachments}
+ * - {@see file_can_download_bug_attachments()}
+ * - {@see file_can_download_bugnote_attachments}
+ *
+ * @param string   $p_action            'view' or 'download'
+ * @param int      $p_bug_id            A bug identifier
+ * @param int      $p_uploader_user_id  The user who uploaded the attachment
+ *
+ * @return bool
+ *
+ * @internal Should not be used outside of File API.
+ */
+function file_can_view_or_download( $p_action, $p_bug_id, $p_uploader_user_id ) {
+	switch( $p_action ) {
+		case 'view':
+			$t_threshold_global = 'view_attachments_threshold';
+			$t_threshold_own = 'allow_view_own_attachments';
+			break;
+		case 'download':
+			$t_threshold_global = 'download_attachments_threshold';
+			$t_threshold_own = 'allow_download_own_attachments';
+			break;
+		default:
+			trigger_error( ERROR_GENERIC, ERROR );
+	}
+
+	$t_project_id = bug_get_field( $p_bug_id, 'project_id' );
+	$t_access_global = config_get( $t_threshold_global,null, null, $t_project_id );
+
+	$t_can_access = access_has_bug_level( $t_access_global, $p_bug_id );
+	if( $t_can_access ) {
+		return true;
+	}
+
+	$t_uploaded_by_me = auth_get_current_user_id() == $p_uploader_user_id;
+	$t_view_own = config_get( $t_threshold_own, null, null, $t_project_id );
+	return $t_uploaded_by_me && $t_view_own;
+}
+
 /**
  * Check if the current user can view attachments for the specified bug.
+ *
  * @param integer $p_bug_id           A bug identifier.
  * @param integer $p_uploader_user_id A user identifier.
+ *
  * @return boolean
  */
 function file_can_view_bug_attachments( $p_bug_id, $p_uploader_user_id = null ) {
-	$t_uploaded_by_me = auth_get_current_user_id() === $p_uploader_user_id;
-	$t_can_view = access_has_bug_level( config_get( 'view_attachments_threshold' ), $p_bug_id );
-	$t_can_view = $t_can_view || ( $t_uploaded_by_me && config_get( 'allow_view_own_attachments' ) );
-	return $t_can_view;
+	return file_can_view_or_download( 'view', $p_bug_id, $p_uploader_user_id );
 }
 
 /**
  * Check if the current user can download attachments for the specified bug.
+ *
  * @param integer $p_bug_id           A bug identifier.
- * @param integer $p_uploader_user_id A user identifier.
+ * @param integer $p_uploader_user_id The user who uploaded the attachment.
+ *
  * @return boolean
  */
 function file_can_download_bug_attachments( $p_bug_id, $p_uploader_user_id = null ) {
-	$t_uploaded_by_me = auth_get_current_user_id() === $p_uploader_user_id;
-	$t_can_download = access_has_bug_level( config_get( 'download_attachments_threshold', null, null, bug_get_field( $p_bug_id, 'project_id' ) ), $p_bug_id );
-	$t_can_download = $t_can_download || ( $t_uploaded_by_me && config_get( 'allow_download_own_attachments', null, null, bug_get_field( $p_bug_id, 'project_id' ) ) );
-	return $t_can_download;
+	return file_can_view_or_download( 'download', $p_bug_id, $p_uploader_user_id );
 }
 
 /**