move some functions around

src/segment-loader.js

@@ -424,9 +424,7 @@ export const shouldFixBadTimelineChanges = (timelineChangeController) => {
 };
 
 /**
- * Fixes certain bad timeline scenarios. In some cases this may be
- * resetting the loaders. In others, it may force a timeline change
- * when a timeline is behind.
+ * Fixes certain bad timeline scenarios by resetting the loader.
  *
  * @param {SegmentLoader} segmentLoader
  */
@@ -435,18 +433,28 @@ export const fixBadTimelineChange = (segmentLoader) => {
     return;
   }
 
+  segmentLoader.pause();
+  segmentLoader.resetEverything();
+  segmentLoader.load();
+};
+
+/**
+ * Check if the pending audio timeline change is behind the
+ * pending main timeline change.
+ *
+ * @param {SegmentLoader} segmentLoader
+ * @return {boolean}
+ */
+const isAudioTimelineBehind = (segmentLoader) => {
   const pendingAudioTimelineChange = segmentLoader.timelineChangeController_.pendingTimelineChange({ type: 'audio' });
   const pendingMainTimelineChange = segmentLoader.timelineChangeController_.pendingTimelineChange({ type: 'main' });
   const hasPendingTimelineChanges = pendingAudioTimelineChange && pendingMainTimelineChange;
 
   if (hasPendingTimelineChanges && pendingAudioTimelineChange.to < pendingMainTimelineChange.to) {
-    segmentLoader.timelineChangeController_.trigger('audioTimelineBehind');
-    return;
+    return true;
   }
 
-  segmentLoader.pause();
-  segmentLoader.resetEverything();
-  segmentLoader.load();
+  return false;
 };
 
 /**
@@ -455,7 +463,7 @@ export const fixBadTimelineChange = (segmentLoader) => {
  *
  * @param {SegmentLoader} segmentLoader
  */
-export const checkAndFixTimelines = (segmentLoader) => {
+const checkAndFixTimelines = (segmentLoader) => {
   const segmentInfo = segmentLoader.pendingSegment_;
 
   if (!segmentInfo) {
@@ -471,6 +479,11 @@ export const checkAndFixTimelines = (segmentLoader) => {
   });
 
   if (waitingForTimelineChange && shouldFixBadTimelineChanges(segmentLoader.timelineChangeController_)) {
+    if (isAudioTimelineBehind) {
+      segmentLoader.timelineChangeController_.trigger('audioTimelineBehind');
+      return;
+    }
+
     fixBadTimelineChange(segmentLoader);
   }
 };