Add Text-To-Speech via Firebase AI Logic

app/src/main/java/com/google/firebase/example/friendlymeals/data/datasource/AIRemoteDataSource.kt

@@ -16,8 +16,13 @@ import com.google.firebase.ai.OnDeviceModelStatus.Companion.DOWNLOADABLE
 import com.google.firebase.ai.OnDeviceModelStatus.Companion.DOWNLOADING
 import com.google.firebase.ai.OnDeviceModelStatus.Companion.UNAVAILABLE
 import com.google.firebase.ai.type.ImagePart
+import com.google.firebase.ai.type.InlineDataPart
 import com.google.firebase.ai.type.PublicPreviewAPI
+import com.google.firebase.ai.type.ResponseModality
+import com.google.firebase.ai.type.SpeechConfig
+import com.google.firebase.ai.type.Voice
 import com.google.firebase.ai.type.content
+import com.google.firebase.ai.type.generationConfig
 import com.google.firebase.example.friendlymeals.data.schema.MealSchema
 import com.google.firebase.example.friendlymeals.data.schema.RecipeSchema
 import com.google.firebase.perf.performance
@@ -152,6 +157,39 @@ class AIRemoteDataSource @Inject constructor(
         }
     }
 
+    suspend fun craftRecipePairing(dishTitle: String, ingredients: List<String>): String {
+        val response = templateGenerativeModel.generateContent(
+            templateId = remoteConfig.getString(RECIPE_PAIRING_KEY),
+            inputs = mapOf(
+                RECIPE_TITLE_FIELD to dishTitle,
+                INGREDIENTS_FIELD to ingredients.joinToString()
+            )
+        )
+
+        return response.text.orEmpty().trim()
+    }
+
+    suspend fun generateSpeech(text: String?): ByteArray? {
+        if (text.isNullOrBlank()) return null
+
+       val model = aiModel.generativeModel(
+            modelName = remoteConfig.getString(TTS_MODEL_KEY),
+            generationConfig = generationConfig {
+                responseModalities = listOf(ResponseModality.AUDIO)
+                speechConfig = SpeechConfig(
+                    voice = Voice(TTS_VOICE),
+                    languageCode = TTS_LANGUAGE
+                )
+            }
+        )
+
+        val voiceProfile = remoteConfig.getString(VOICE_PROFILE_KEY)
+        val response = model.generateContent("$voiceProfile $text")
+        val part = response.candidates.firstOrNull()?.content?.parts?.firstOrNull()
+
+        return (part as? InlineDataPart)?.inlineData
+    }
+
     suspend fun loadOnDeviceModel() {
         when (hybridGenerativeModel.onDeviceExtension?.checkStatus()) {
             UNAVAILABLE -> {
@@ -191,6 +229,9 @@ class AIRemoteDataSource @Inject constructor(
         private const val FIND_STORES_KEY = "find_stores"
         private const val HYBRID_CLOUD_MODEL_KEY = "hybrid_cloud_model"
         private const val HYBRID_INGREDIENTS_PROMPT_KEY = "hybrid_ingredients_prompt"
+        private const val RECIPE_PAIRING_KEY = "recipe_pairing"
+        private const val VOICE_PROFILE_KEY = "recipe_pairing_voice_profile"
+        private const val TTS_MODEL_KEY = "tts_model"
 
         //Template input fields
         private const val IMAGE_DATA_FIELD = "imageData"
@@ -207,6 +248,10 @@ class AIRemoteDataSource @Inject constructor(
         //Grounding with Maps config
         private const val LANGUAGE = "en_US"
 
+        //TTS config
+        private const val TTS_VOICE = "Charon"
+        private const val TTS_LANGUAGE = "en-US"
+
         //Class TAG
         private const val TAG = "AIRemoteDataSource"
     }

app/src/main/java/com/google/firebase/example/friendlymeals/data/repository/AIRepository.kt

@@ -42,6 +42,14 @@ class AIRepository @Inject constructor(
         return aiRemoteDataSource.scanMeal(imageData)
     }
 
+    suspend fun craftRecipePairing(dishTitle: String, ingredients: List<String>): String {
+        return aiRemoteDataSource.craftRecipePairing(dishTitle, ingredients)
+    }
+
+    suspend fun generateSpeech(text: String?): ByteArray? {
+        return aiRemoteDataSource.generateSpeech(text)
+    }
+
     suspend fun loadOnDeviceModel() {
         aiRemoteDataSource.loadOnDeviceModel()
     }

app/src/main/java/com/google/firebase/example/friendlymeals/ui/recipe/RecipeScreen.kt

@@ -26,6 +26,7 @@ import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.Scaffold
@@ -82,7 +83,8 @@ fun RecipeScreen(
             viewModel.addIngredientsToGroceryList(recipeViewState.value.recipe.ingredients) {
                 Toast.makeText(context, groceryListToast, Toast.LENGTH_SHORT).show()
             }
-        }
+        },
+        onPairingClick = viewModel::onPairingClick
     )
 }
 
@@ -93,7 +95,8 @@ fun RecipeScreenContent(
     leaveReview: (Int) -> Unit = {},
     recipeViewState: RecipeViewState,
     onLiveAssistantClick: () -> Unit = {},
-    onAddIngredientsToGrocery: () -> Unit = {}
+    onAddIngredientsToGrocery: () -> Unit = {},
+    onPairingClick: () -> Unit = {}
 ) {
     val context = LocalContext.current
     val multiplePermissionsLauncher = rememberLauncherForActivityResult(
@@ -238,6 +241,13 @@ fun RecipeScreenContent(
                             }
                         }
 
+                        Spacer(modifier = Modifier.height(16.dp))
+
+                        PairingGuideButton(
+                            audioState = recipeViewState.audioState,
+                            onClick = onPairingClick
+                        )
+
                         Spacer(modifier = Modifier.height(24.dp))
 
                         Row(
@@ -461,6 +471,117 @@ fun IngredientRow(text: String) {
     }
 }
 
+@Composable
+fun PairingGuideButton(
+    audioState: RecipeAudioState,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier
+) {
+    val containerColor = when (audioState) {
+        is RecipeAudioState.Playing, is RecipeAudioState.Paused -> Teal
+        is RecipeAudioState.LoadingAudio -> LightTeal
+        is RecipeAudioState.Error -> Color(0xFFFFEBEE)
+        is RecipeAudioState.Idle -> LightTeal
+    }
+
+    val contentColor = when (audioState) {
+        is RecipeAudioState.Playing, is RecipeAudioState.Paused -> Color.White
+        is RecipeAudioState.Error -> Color.Red
+        else -> Teal
+    }
+
+    Button(
+        onClick = onClick,
+        colors = ButtonDefaults.buttonColors(
+            containerColor = containerColor,
+            contentColor = contentColor
+        ),
+        shape = RoundedCornerShape(16.dp),
+        modifier = modifier
+            .fillMaxWidth()
+            .height(52.dp)
+    ) {
+        Row(
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.Center
+        ) {
+            when (audioState) {
+                is RecipeAudioState.LoadingAudio -> {
+                    CircularProgressIndicator(
+                        modifier = Modifier.size(18.dp),
+                        color = Teal,
+                        strokeWidth = 2.dp
+                    )
+                    Spacer(modifier = Modifier.width(10.dp))
+                    Text(
+                        text = stringResource(R.string.recipe_pairing_loading_audio),
+                        fontSize = 15.sp,
+                        fontWeight = FontWeight.Bold,
+                        color = Teal
+                    )
+                }
+
+                is RecipeAudioState.Playing -> {
+                    Icon(
+                        painter = painterResource(R.drawable.ic_pause),
+                        contentDescription = null,
+                        tint = Color.White,
+                        modifier = Modifier.size(20.dp)
+                    )
+                    Spacer(modifier = Modifier.width(10.dp))
+                    Text(
+                        text = stringResource(R.string.recipe_pairing_playing),
+                        fontSize = 15.sp,
+                        fontWeight = FontWeight.Bold,
+                        color = Color.White
+                    )
+                }
+
+                is RecipeAudioState.Paused -> {
+                    Icon(
+                        painter = painterResource(R.drawable.ic_play_arrow),
+                        contentDescription = null,
+                        tint = Color.White,
+                        modifier = Modifier.size(20.dp)
+                    )
+                    Spacer(modifier = Modifier.width(10.dp))
+                    Text(
+                        text = stringResource(R.string.recipe_pairing_paused),
+                        fontSize = 15.sp,
+                        fontWeight = FontWeight.Bold,
+                        color = Color.White
+                    )
+                }
+
+                is RecipeAudioState.Error -> {
+                    Text(
+                        text = stringResource(R.string.recipe_pairing_retry),
+                        fontSize = 14.sp,
+                        fontWeight = FontWeight.Bold,
+                        color = Color.Red
+                    )
+                }
+
+                is RecipeAudioState.Idle -> {
+                    Icon(
+                        painter = painterResource(R.drawable.ic_drink),
+                        contentDescription = null,
+                        tint = Teal,
+                        modifier = Modifier.size(20.dp)
+                    )
+                    Spacer(modifier = Modifier.width(10.dp))
+                    Text(
+                        text = stringResource(R.string.recipe_pairing_french_wine),
+                        fontSize = 15.sp,
+                        fontWeight = FontWeight.Bold,
+                        color = Teal
+                    )
+                }
+            }
+        }
+    }
+}
+
 @Preview
 @Composable
 fun RecipeScreenPreview() {

app/src/main/java/com/google/firebase/example/friendlymeals/ui/recipe/RecipeViewModel.kt

@@ -3,10 +3,12 @@ package com.google.firebase.example.friendlymeals.ui.recipe
 import androidx.lifecycle.SavedStateHandle
 import androidx.navigation.toRoute
 import com.google.firebase.example.friendlymeals.MainViewModel
-import com.google.firebase.example.friendlymeals.data.model.Review
 import com.google.firebase.example.friendlymeals.data.model.Like
+import com.google.firebase.example.friendlymeals.data.model.Review
+import com.google.firebase.example.friendlymeals.data.repository.AIRepository
 import com.google.firebase.example.friendlymeals.data.repository.AuthRepository
 import com.google.firebase.example.friendlymeals.data.repository.DatabaseRepository
+import com.google.firebase.example.friendlymeals.ui.shared.AudioComponent
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -17,7 +19,8 @@ import javax.inject.Inject
 class RecipeViewModel @Inject constructor(
     savedStateHandle: SavedStateHandle,
     private val authRepository: AuthRepository,
-    private val databaseRepository: DatabaseRepository
+    private val databaseRepository: DatabaseRepository,
+    private val aiRepository: AIRepository
 ) : MainViewModel() {
     private val recipeRoute = savedStateHandle.toRoute<RecipeRoute>()
     private val recipeId: String = recipeRoute.recipeId
@@ -28,21 +31,100 @@ class RecipeViewModel @Inject constructor(
 
     val userId: String get() = authRepository.currentUser?.uid.orEmpty()
 
+    private val audioComponent = AudioComponent()
+    private var cachedAudioData: ByteArray? = null
+    private var cachedPairingText: String? = null
+
     init {
         loadRecipe()
     }
 
     fun loadRecipe() {
         launchCatching {
+            val recipe = databaseRepository.getRecipe(recipeId)
             _recipeViewState.value = RecipeViewState(
                 recipeId = recipeId,
-                recipe = databaseRepository.getRecipe(recipeId),
+                recipe = recipe,
                 favorite = loadFavorite(),
-                rating = loadRating()
+                rating = loadRating(),
+                audioState = RecipeAudioState.Idle
             )
         }
     }
 
+    fun onPairingClick() {
+        when (_recipeViewState.value.audioState) {
+            is RecipeAudioState.Playing -> {
+                audioComponent.pause()
+                _recipeViewState.value = _recipeViewState.value.copy(
+                    audioState = RecipeAudioState.Paused
+                )
+            }
+            is RecipeAudioState.Paused -> {
+                audioComponent.resume()
+                _recipeViewState.value = _recipeViewState.value.copy(
+                    audioState = RecipeAudioState.Playing
+                )
+            }
+            is RecipeAudioState.LoadingAudio -> {
+                // Already loading audio, do nothing
+            }
+            is RecipeAudioState.Idle, is RecipeAudioState.Error -> {
+                if (cachedAudioData != null) {
+                    playCachedAudio()
+                } else {
+                    launchCatching { generatePairingAndAudio() }
+                }
+            }
+        }
+    }
+
+    private fun playCachedAudio() {
+        val audioData = cachedAudioData ?: return
+
+        _recipeViewState.value = _recipeViewState.value.copy(
+            audioState = RecipeAudioState.Playing
+
+        )
+        audioComponent.play(audioData) {
+            _recipeViewState.value = _recipeViewState.value.copy(
+                audioState = RecipeAudioState.Idle
+            )
+        }
+    }
+
+    private suspend fun generatePairingAndAudio() {
+        _recipeViewState.value = _recipeViewState.value.copy(
+            audioState = RecipeAudioState.LoadingAudio
+        )
+
+
+        if (cachedPairingText.isNullOrBlank()) {
+            val recipe = _recipeViewState.value.recipe
+            val generated = aiRepository.craftRecipePairing(recipe.title, recipe.ingredients)
+            cachedPairingText = generated
+        }
+
+        val audio = aiRepository.generateSpeech(cachedPairingText)
+
+        if (audio != null && audio.isNotEmpty()) {
+            cachedAudioData = audio
+            _recipeViewState.value = _recipeViewState.value.copy(
+                audioState = RecipeAudioState.Playing
+            )
+            audioComponent.play(audio) {
+                _recipeViewState.value = _recipeViewState.value.copy(
+                    audioState = RecipeAudioState.Idle
+                )
+            }
+        } else {
+            _recipeViewState.value = _recipeViewState.value.copy(
+                audioState = RecipeAudioState.Error("Could not generate audio")
+            )
+        }
+
+    }
+
     private suspend fun loadFavorite(): Boolean {
         return databaseRepository.getFavorite(userId, recipeId)
     }
@@ -94,4 +176,9 @@ class RecipeViewModel @Inject constructor(
             onSuccess()
         }
     }
+
+    override fun onCleared() {
+        audioComponent.release()
+        super.onCleared()
+    }
 }