stream-controller: allow start level loading retry even if media not …

…attached

# Conflicts:
#	src/controller/stream-controller.js

src/controller/stream-controller.js

@@ -190,8 +190,8 @@ class StreamController extends EventHandler {
     // if video not attached AND
     // start fragment already requested OR start frag prefetch disable
     // exit loop
-    // => if media not attached but start frag prefetch is enabled and start frag not requested yet, we will not exit loop
-    if (!media &&
+    // => if start level loaded and media not attached but start frag prefetch is enabled and start frag not requested yet, we will not exit loop
+    if (this.levelLastLoaded !== undefined && !media &&
       (this.startFragRequested || !config.startFragPrefetch)) {
       return true;
     }
@@ -204,12 +204,14 @@ class StreamController extends EventHandler {
       pos = this.nextLoadPosition;
     }
     // determine next load level
-    let level = hls.nextLoadLevel;
+    let level = hls.nextLoadLevel,
+        levelInfo = this.levels[level],
+        levelBitrate = levelInfo.bitrate,
+        maxBufLen;
 
     // compute max Buffer Length that we could get from this load level, based on level bitrate. don't buffer more than 60 MB and more than 30s
-    let maxBufLen;
-    if ((this.levels[level]).hasOwnProperty('bitrate')) {
-      maxBufLen = Math.max(8 * config.maxBufferSize / this.levels[level].bitrate, config.maxBufferLength);
+    if (levelBitrate) {
+      maxBufLen = Math.max(8 * config.maxBufferSize / levelBitrate, config.maxBufferLength);
     } else {
       maxBufLen = config.maxBufferLength;
     }
@@ -229,10 +231,9 @@ class StreamController extends EventHandler {
     logger.trace(`buffer length of ${bufferLen.toFixed(3)} is below max of ${maxBufLen.toFixed(3)}. checking for more payload ...`);
 
     // set next load level : this will trigger a playlist load if needed
-    hls.nextLoadLevel = level;
-    this.level = level;
+    this.level = hls.nextLoadLevel = level;
 
-    const levelDetails = this.levels[level].details;
+    const levelDetails = levelInfo.details;
     // if level info not retrieved yet, switch state and wait for level retrieval
     // if live playlist, ensure that new playlist has been refreshed to avoid loading/try to load
     // a useless and outdated fragment (that might even introduce load error if it is already out of the live playlist)