feat!: Application outline

2024-07-23 00:55:59 +02:00 · 2024-07-23 00:55:59 +02:00 · 01fbf32042
commit 01fbf32042
parent 80dfa6ab4e
9 changed files with 1440 additions and 190 deletions
--- a/app/src/main/java/eu/ztsh/garmin/mapbox/VoiceControl.kt
+++ b/app/src/main/java/eu/ztsh/garmin/mapbox/VoiceControl.kt
@ -0,0 +1,111 @@
+package eu.ztsh.garmin.mapbox
+
+import android.content.Context
+import com.mapbox.bindgen.Expected
+import com.mapbox.navigation.core.trip.session.VoiceInstructionsObserver
+import com.mapbox.navigation.ui.base.util.MapboxNavigationConsumer
+import com.mapbox.navigation.voice.api.MapboxSpeechApi
+import com.mapbox.navigation.voice.api.MapboxVoiceInstructionsPlayer
+import com.mapbox.navigation.voice.model.SpeechAnnouncement
+import com.mapbox.navigation.voice.model.SpeechError
+import com.mapbox.navigation.voice.model.SpeechValue
+import com.mapbox.navigation.voice.model.SpeechVolume
+import eu.ztsh.garmin.UI
+import java.util.*
+
+class VoiceControl(private val ui: UI, context: Context) {
+
+    /**
+     * Extracts message that should be communicated to the driver about the upcoming maneuver.
+     * When possible, downloads a synthesized audio file that can be played back to the driver.
+     */
+    private lateinit var speechApi: MapboxSpeechApi
+
+    /**
+     * Plays the synthesized audio files with upcoming maneuver instructions
+     * or uses an on-device Text-To-Speech engine to communicate the message to the driver.
+     * NOTE: do not use lazy initialization for this class since it takes some time to initialize
+     * the system services required for on-device speech synthesis. With lazy initialization
+     * there is a high risk that said services will not be available when the first instruction
+     * has to be played. [MapboxVoiceInstructionsPlayer] should be instantiated in
+     * `Activity#onCreate`.
+     */
+    private lateinit var voiceInstructionsPlayer: MapboxVoiceInstructionsPlayer
+
+    init {
+        speechApi = MapboxSpeechApi(
+            context,
+            Locale("pl").language
+        )
+        voiceInstructionsPlayer = MapboxVoiceInstructionsPlayer(
+            context,
+            Locale("pl").language
+        )
+        ui.soundButton.setOnClickListener {
+            // mute/unmute voice instructions
+            isVoiceInstructionsMuted = !isVoiceInstructionsMuted
+        }
+    }
+
+    /**
+     * Stores and updates the state of whether the voice instructions should be played as they come or muted.
+     */
+    private var isVoiceInstructionsMuted = false
+        set(value) {
+            field = value
+            if (value) {
+                ui.soundButton.muteAndExtend(UI.BUTTON_ANIMATION_DURATION)
+                voiceInstructionsPlayer.volume(SpeechVolume(0f))
+            } else {
+                ui.soundButton.unmuteAndExtend(UI.BUTTON_ANIMATION_DURATION)
+                voiceInstructionsPlayer.volume(SpeechVolume(1f))
+            }
+        }
+
+    /**
+     * Observes when a new voice instruction should be played.
+     */
+    val voiceInstructionsObserver = VoiceInstructionsObserver { voiceInstructions ->
+        speechApi.generate(voiceInstructions, speechCallback)
+    }
+
+    /**
+     * Based on whether the synthesized audio file is available, the callback plays the file
+     * or uses the fall back which is played back using the on-device Text-To-Speech engine.
+     */
+    private val speechCallback =
+        MapboxNavigationConsumer<Expected<SpeechError, SpeechValue>> { expected ->
+            expected.fold(
+                { error ->
+                    // play the instruction via fallback text-to-speech engine
+                    voiceInstructionsPlayer.play(
+                        error.fallback,
+                        voiceInstructionsPlayerCallback
+                    )
+                },
+                { value ->
+                    // play the sound file from the external generator
+                    voiceInstructionsPlayer.play(
+                        value.announcement,
+                        voiceInstructionsPlayerCallback
+                    )
+                }
+            )
+        }
+
+    /**
+     * When a synthesized audio file was downloaded, this callback cleans up the disk after it was played.
+     */
+    private val voiceInstructionsPlayerCallback =
+        MapboxNavigationConsumer<SpeechAnnouncement> { value ->
+            // remove already consumed file to free-up space
+            speechApi.clean(value)
+        }
+
+    fun cancel() {
+        speechApi.cancel()
+        voiceInstructionsPlayer.shutdown()
+
+    }
+
+}