From 2fc0c935c42cc5ef93e2a3c8644b7d0216cfad7b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Velad=20Galv=C3=A1n?= <ladvan91@hotmail.com>
Date: Mon, 29 Apr 2024 21:22:29 +0200
Subject: [PATCH] feat(DASH): Add manifest.dash.enableFastSwitching config
 (#6500)

---
 demo/config.js                   | 4 +++-
 externs/shaka/player.js          | 6 +++++-
 lib/dash/dash_parser.js          | 3 ++-
 lib/util/player_configuration.js | 1 +
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/demo/config.js b/demo/config.js
index 15e14540bb..22b6fb984b 100644
--- a/demo/config.js
+++ b/demo/config.js
@@ -235,7 +235,9 @@ shakaDemo.Config = class {
         .addBoolInput_('Use stream once in period flattening',
             'manifest.dash.useStreamOnceInPeriodFlattening')
         .addNumberInput_('override the Update period of dash manifest',
-            'manifest.dash.updatePeriod');
+            'manifest.dash.updatePeriod')
+        .addBoolInput_('Enable fast switching',
+            'manifest.dash.enableFastSwitching');
   }
 
   /** @private */
diff --git a/externs/shaka/player.js b/externs/shaka/player.js
index 420b2015a9..df8f904725 100644
--- a/externs/shaka/player.js
+++ b/externs/shaka/player.js
@@ -906,7 +906,8 @@ shaka.extern.xml.Node;
  *   enableAudioGroups: boolean,
  *   multiTypeVariantsAllowed: boolean,
  *   useStreamOnceInPeriodFlattening: boolean,
- *   updatePeriod: number
+ *   updatePeriod: number,
+ *   enableFastSwitching: boolean
  * }}
  *
  * @property {string} clockSyncUri
@@ -995,6 +996,9 @@ shaka.extern.xml.Node;
  *   manifest less frequently. if you update the value during for a dynamic
  *   manifest, it will directly trigger a new download of the manifest
  *   Defaults to <code>-1</code>.
+ * @property {boolean} enableFastSwitching
+ *   If false, disables fast switching track recognition.
+ *   Defaults to <code>true</code>.
  * @exportDoc
  */
 shaka.extern.DashManifestConfiguration;
diff --git a/lib/dash/dash_parser.js b/lib/dash/dash_parser.js
index 71aac7902c..40f99220fa 100644
--- a/lib/dash/dash_parser.js
+++ b/lib/dash/dash_parser.js
@@ -1176,7 +1176,8 @@ shaka.dash.DashParser = class {
       } else if (schemeId == colourPrimariesScheme ||
                  schemeId == matrixCoefficientsScheme) {
         continue;
-      } else if (schemeId == 'urn:mpeg:dash:ssr:2023') {
+      } else if (schemeId == 'urn:mpeg:dash:ssr:2023' &&
+          this.config_.dash.enableFastSwitching) {
         isFastSwitching = true;
       } else {
         unrecognizedEssentialProperty = true;
diff --git a/lib/util/player_configuration.js b/lib/util/player_configuration.js
index e318318f5d..75b4db1e5c 100644
--- a/lib/util/player_configuration.js
+++ b/lib/util/player_configuration.js
@@ -150,6 +150,7 @@ shaka.util.PlayerConfiguration = class {
         multiTypeVariantsAllowed,
         useStreamOnceInPeriodFlattening: false,
         updatePeriod: -1,
+        enableFastSwitching: true,
       },
       hls: {
         ignoreTextStreamFailures: false,