Merge branch 'patch/v1.6.x'

* patch/v1.6.x:
  Increase minimum Windows test version for saucelabs
  Fix FairPlay key ID patching Fixes "keyId is null" error mentioned in #7542 (comment) #7654
  Fix fallback to primary on live start Fixes #7641
  Do not reset interstitial when seeking between assets Fixes #7640
  Fixed issue with progressive loading of subtitles by disabling progressive loading for webVTT (#7649)
  Fix audio TS segment duration calculation ##7646 (comment)
  Resolve end-of-stream with empty or gap segments at end of playlist Fixes #7572 (and maybe #7564)
  Fix issue where some devices not works with playready (#7631)
  Fix switching back to main audio after end-of-stream buffered Fixes #7643

Author: robwalch

api-extractor/report/hls.js.api.md

@@ -3358,6 +3358,8 @@ export class LevelDetails {
 export class LevelKey implements DecryptData {
     constructor(method: string, uri: string, format: string, formatversions?: number[], iv?: Uint8Array<ArrayBuffer> | null, keyId?: string);
     // (undocumented)
+    static addKeyIdForUri(uri: string): Uint8Array<ArrayBuffer>;
+    // (undocumented)
     static clearKeyUriToKeyIdMap(): void;
     // (undocumented)
     readonly encrypted: boolean;

src/loader/key-loader.ts

@@ -265,14 +265,22 @@ export default class KeyLoader extends Logger implements ComponentAPI {
           frag.initSegment.data as Uint8Array<ArrayBuffer>,
         );
         if (keyIds.length) {
-          const keyId = keyIds[0];
+          let keyId = keyIds[0];
           if (keyId.some((b) => b !== 0)) {
             this.log(`Using keyId found in init segment ${arrayToHex(keyId)}`);
-            keyInfo.decryptdata.keyId = keyId;
             LevelKey.setKeyIdForUri(keyInfo.decryptdata.uri, keyId);
+          } else {
+            keyId = LevelKey.addKeyIdForUri(keyInfo.decryptdata.uri);
+            this.log(`Generating keyId to patch media ${arrayToHex(keyId)}`);
           }
+          keyInfo.decryptdata.keyId = keyId;
         }
       }
+      if (!keyInfo.decryptdata.keyId && !isMediaFragment(frag)) {
+        // Resolve so that unencrypted init segment is loaded
+        // key id is extracted from tenc box when processing key for next segment above
+        return Promise.resolve(keyLoadedData);
+      }
       const keySessionContextPromise =
         this.emeController.loadKey(keyLoadedData);
       return (keyInfo.keyLoadPromise = keySessionContextPromise.then(

src/loader/level-key.ts

@@ -41,6 +41,15 @@ export class LevelKey implements DecryptData {
     keyUriToKeyIdMap[uri] = keyId;
   }
 
+  static addKeyIdForUri(uri: string): Uint8Array<ArrayBuffer> {
+    const val = Object.keys(keyUriToKeyIdMap).length % Number.MAX_SAFE_INTEGER;
+    const keyId = new Uint8Array(16);
+    const dv = new DataView(keyId.buffer, 12, 4); // Just set the last 4 bytes
+    dv.setUint32(0, val);
+    keyUriToKeyIdMap[uri] = keyId;
+    return keyId;
+  }
+
   constructor(
     method: string,
     uri: string,