NAVAND-1001: share lastPlayedInstructions between MapboxAudioGuidanceVoice instances

Author: dzinad

libnavui-voice/src/main/java/com/mapbox/navigation/ui/voice/api/MapboxAudioGuidance.kt

@@ -27,6 +27,7 @@ import kotlinx.coroutines.flow.filter
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.flatMapConcat
 import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.flatMapMerge
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.updateAndGet
@@ -123,12 +124,12 @@ internal constructor(
     /**
      * Top level flow that will switch based on the language and muted state.
      */
-    @OptIn(ExperimentalCoroutinesApi::class, FlowPreview::class)
+    @OptIn(ExperimentalCoroutinesApi::class)
     private fun audioGuidanceFlow(
         mapboxNavigation: MapboxNavigation
     ): Flow<MapboxAudioGuidanceState> {
-        return mapboxNavigation.audioGuidanceVoice().flatMapLatest { audioGuidance ->
-            var lastPlayedInstructions: VoiceInstructions? = null
+        var lastPlayedInstructions: VoiceInstructions? = null
+        return mapboxNavigation.audioGuidanceVoice().flatMapMerge { audioGuidance ->
             mutedStateFlow.flatMapLatest { isMuted ->
                 val voiceInstructions = mapboxVoiceInstructions.voiceInstructions()
                     .map { state ->
@@ -146,18 +147,15 @@ internal constructor(
                 } else {
                     voiceInstructions
                         .filter { it.voiceInstructions != lastPlayedInstructions }
-                        .flatMapConcat {
+                        .map {
                             lastPlayedInstructions = it.voiceInstructions
                             val announcement = audioGuidance.speak(it.voiceInstructions)
-                            flowOf(announcement)
-                        }
-                        .map { speechAnnouncement ->
-                            internalStateFlow.updateAndGet {
+                            internalStateFlow.updateAndGet { state ->
                                 MapboxAudioGuidanceState(
-                                    isPlayable = it.isPlayable,
-                                    isMuted = it.isMuted,
-                                    voiceInstructions = it.voiceInstructions,
-                                    speechAnnouncement = speechAnnouncement
+                                    isPlayable = state.isPlayable,
+                                    isMuted = state.isMuted,
+                                    voiceInstructions = state.voiceInstructions,
+                                    speechAnnouncement = announcement
                                 )
                             }
                         }