From 925cb393973e6d4f5a8a990e9686bbc511a712a4 Mon Sep 17 00:00:00 2001
From: Stanislav Dmitrenko <7953703+avently@users.noreply.github.com>
Date: Fri, 19 Apr 2024 23:37:47 +0700
Subject: [PATCH] desktop: using system sound in screenshare (#4035)

Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com>
---
 .../commonMain/resources/assets/www/call.js   | 22 ++++++++++++++++---
 packages/simplex-chat-webrtc/src/call.ts      | 17 ++++++++++++--
 2 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/apps/multiplatform/common/src/commonMain/resources/assets/www/call.js b/apps/multiplatform/common/src/commonMain/resources/assets/www/call.js
index 9e7d29189f..218fe0c660 100644
--- a/apps/multiplatform/common/src/commonMain/resources/assets/www/call.js
+++ b/apps/multiplatform/common/src/commonMain/resources/assets/www/call.js
@@ -486,8 +486,22 @@ const processCommand = (function () {
             }
             return;
         }
-        for (const t of call.localStream.getTracks())
-            t.stop();
+        if (!call.screenShareEnabled) {
+            for (const t of call.localStream.getTracks())
+                t.stop();
+        }
+        else {
+            // Don't stop audio track if switching to screenshare
+            for (const t of call.localStream.getVideoTracks())
+                t.stop();
+            // Replace new track from screenshare with old track from recording device
+            for (const t of localStream.getAudioTracks()) {
+                t.stop();
+                localStream.removeTrack(t);
+            }
+            for (const t of call.localStream.getAudioTracks())
+                localStream.addTrack(t);
+        }
         call.localCamera = camera;
         const audioTracks = localStream.getAudioTracks();
         const videoTracks = localStream.getVideoTracks();
@@ -547,7 +561,9 @@ const processCommand = (function () {
                 //},
                 //aspectRatio: 1.33,
             },
-            audio: true,
+            audio: false,
+            // This works with Chrome, Edge, Opera, but not with Firefox and Safari
+            // systemAudio: "include"
         };
         return navigator.mediaDevices.getDisplayMedia(constraints);
     }
diff --git a/packages/simplex-chat-webrtc/src/call.ts b/packages/simplex-chat-webrtc/src/call.ts
index 41241e22c2..e7788ac723 100644
--- a/packages/simplex-chat-webrtc/src/call.ts
+++ b/packages/simplex-chat-webrtc/src/call.ts
@@ -689,7 +689,18 @@ const processCommand = (function () {
       }
       return
     }
-    for (const t of call.localStream.getTracks()) t.stop()
+    if (!call.screenShareEnabled) {
+      for (const t of call.localStream.getTracks()) t.stop()
+    } else {
+      // Don't stop audio track if switching to screenshare
+      for (const t of call.localStream.getVideoTracks()) t.stop()
+      // Replace new track from screenshare with old track from recording device
+      for (const t of localStream.getAudioTracks()) {
+        t.stop()
+        localStream.removeTrack(t)
+      }
+      for (const t of call.localStream.getAudioTracks()) localStream.addTrack(t)
+    }
     call.localCamera = camera
 
     const audioTracks = localStream.getAudioTracks()
@@ -755,7 +766,9 @@ const processCommand = (function () {
         //},
         //aspectRatio: 1.33,
       },
-      audio: true,
+      audio: false,
+      // This works with Chrome, Edge, Opera, but not with Firefox and Safari
+      // systemAudio: "include"
     }
     return navigator.mediaDevices.getDisplayMedia(constraints)
   }