Basic API ability

.idea/.gitignore

@@ -1,3 +1,5 @@
 # Default ignored files
 /shelf/
 /workspace.xml
+
+deploymentTargetSelector.xml

.idea/deploymentTargetSelector.xml

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="deploymentTargetSelector">
-    <selectionStates>
-      <SelectionState runConfigName="app">
-        <option name="selectionMode" value="DROPDOWN" />
-      </SelectionState>
-    </selectionStates>
-  </component>
-</project>

app/build.gradle.kts

@@ -64,5 +64,6 @@ dependencies {
     androidTestImplementation(libs.androidx.ui.test.junit4)
     debugImplementation(libs.androidx.ui.tooling)
     debugImplementation(libs.androidx.ui.test.manifest)
+    debugImplementation(libs.logging.interceptor)
     ksp(libs.hilt.compiler)
 }

app/src/main/java/eu/m724/chatapp/activity/chat/ChatActivity.kt

@@ -1,6 +1,7 @@
 package eu.m724.chatapp.activity.chat
 
 import android.os.Bundle
+import android.widget.Toast
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
@@ -45,6 +46,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalSoftwareKeyboardController
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
@@ -73,6 +75,7 @@ fun Content(
 ) {
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
     val localSoftwareKeyboardController = LocalSoftwareKeyboardController.current
+    val context = LocalContext.current
 
     var composerValue by remember { mutableStateOf("") }
     val composerFocusRequester = remember { FocusRequester() }
@@ -81,8 +84,12 @@ fun Content(
 
     LaunchedEffect(uiState.requestInProgress) { // TODO probably not the best way
         if (!uiState.requestInProgress) {
-            composerValue = ""
-            composerFocusRequester.requestFocus() // TODO maybe make toggleable? or smart?
+            if (uiState.requestLastError == null) {
+                composerValue = ""
+                composerFocusRequester.requestFocus() // TODO maybe make toggleable? or smart?
+            } else {
+                Toast.makeText(context, uiState.requestLastError, Toast.LENGTH_SHORT).show() // TODO better way of showing this
+            }
         } else {
             if (!uiState.messageHistory.isEmpty()) {
                 lazyListState.animateScrollToItem(uiState.messageHistory.size)
@@ -168,7 +175,7 @@ fun ChatTopAppBar(
             ) {
                 AnimatedChangingText(
                     text = title,
-                )
+                )  // TODO fade
             }
         }
     )
@@ -176,9 +183,9 @@ fun ChatTopAppBar(
 
 @Composable
 fun MessageExchange(
-    modifier: Modifier = Modifier,
     isComposing: Boolean,
     composerValue: String,
+    modifier: Modifier = Modifier,
     onComposerValueChange: (String) -> Unit = {},
     composerFocusRequester: FocusRequester = FocusRequester(),
     responseValue: String = "",

app/src/main/java/eu/m724/chatapp/activity/chat/ChatActivityUiState.kt

@@ -1,10 +1,30 @@
 package eu.m724.chatapp.activity.chat
 
 data class ChatActivityUiState(
+    /**
+     * The title of the current chat
+     */
     val chatTitle: String? = null,
+
+    /**
+     * Whether a request is in progress (a response is streaming)
+     */
     val requestInProgress: Boolean = false,
+
+    /**
+     * The response right now, updates when streaming
+     */
     val currentMessageResponse: String = "",
-    val messageHistory: List<ChatMessageExchange> = listOf()
+
+    /**
+     * All the messages of this chat
+     */
+    val messageHistory: List<ChatMessageExchange> = listOf(),
+
+    /**
+     * Error, if any, of the last request
+     */
+    val requestLastError: String? = null
 )
 
 data class ChatMessageExchange(

app/src/main/java/eu/m724/chatapp/activity/chat/ChatActivityViewModel.kt

@@ -4,7 +4,8 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import eu.m724.chatapp.api.AiApiService
-import kotlinx.coroutines.delay
+import eu.m724.chatapp.api.data.ChatMessage
+import eu.m724.chatapp.api.data.request.ChatCompletionRequest
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -19,13 +20,9 @@ class ChatActivityViewModel @Inject constructor(
     private val _uiState = MutableStateFlow(ChatActivityUiState())
     val uiState: StateFlow<ChatActivityUiState> = _uiState.asStateFlow()
 
-    val responses = arrayOf(
-        "Hello right back at you! How can I help you today?",
-        "I'm sorry, but I can't assist with that."
-    )
+    private val messages = mutableListOf<ChatMessage>()
 
     fun sendMessage(message: String) {
-
         _uiState.update {
             it.copy(
                 requestInProgress = true,
@@ -39,26 +36,44 @@ class ChatActivityViewModel @Inject constructor(
             }
         }
 
+        messages.add(ChatMessage(
+            role = ChatMessage.Role.USER,
+            content = message
+        ))
+
 
         viewModelScope.launch {
-            val response = responses.random()
-            val targetResponseParts = response.split(" ")
-
-            for (part in targetResponseParts) {
-                delay(50)
+            val response = aiApiService.chatComplete(ChatCompletionRequest(
+                model = "free-model",
+                messages = messages,
+                temperature = 1.0f,
+                maxTokens = 128,
+                frequencyPenalty = 0.0f,
+                presencePenalty = 0.0f
+            ))
 
+            if (!response.isSuccessful || response.body() == null) {
                 _uiState.update {
                     it.copy(
-                        currentMessageResponse = it.currentMessageResponse.trim() + " $part"
+                        requestInProgress = false,
+                        requestLastError = response.code().toString()
                     )
                 }
+
+                // TODO launch toast or something
+                return@launch
             }
 
+            val completion = response.body()!!
+            val choice = completion.choices[0]
+
+            messages.add(choice.message)
+
             _uiState.update {
                 it.copy(
                     requestInProgress = false,
                     messageHistory = it.messageHistory.plus(
-                        ChatMessageExchange(message, response)
+                        ChatMessageExchange(message, choice.message.content)
                     )
                 )
             }

app/src/main/java/eu/m724/chatapp/activity/select/SelectModelActivity.kt

@@ -59,7 +59,7 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
-import eu.m724.chatapp.api.response.LanguageModel
+import eu.m724.chatapp.api.data.response.LanguageModel
 import java.math.RoundingMode
 import java.text.DecimalFormat
 

app/src/main/java/eu/m724/chatapp/activity/select/SelectModelUiState.kt

@@ -1,6 +1,6 @@
 package eu.m724.chatapp.activity.select
 
-import eu.m724.chatapp.api.response.LanguageModel
+import eu.m724.chatapp.api.data.response.LanguageModel
 
 data class SelectModelUiState(
     val models: List<LanguageModel> = listOf()

app/src/main/java/eu/m724/chatapp/api/AiApiNetworkModule.kt

@@ -1,11 +1,14 @@
 package eu.m724.chatapp.api
 
+import com.google.gson.FieldNamingPolicy
+import com.google.gson.GsonBuilder
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
 import dagger.hilt.components.SingletonComponent
 import eu.m724.chatapp.BuildConfig
 import okhttp3.OkHttpClient
+import okhttp3.logging.HttpLoggingInterceptor
 import retrofit2.Retrofit
 import retrofit2.converter.gson.GsonConverterFactory
 import javax.inject.Singleton
@@ -16,25 +19,33 @@ object AiApiNetworkModule {
     @Provides
     @Singleton
     fun provideOkHttpClient(): OkHttpClient {
-        return OkHttpClient.Builder()
-            .addInterceptor {
-                it.proceed(
-                    it.request().newBuilder()
-                        .header("User-Agent", BuildConfig.USER_AGENT)
-                        .build()
-                )
-                    // TODO add api key here
-            }
-            .build()
+        val interceptor = AiApiRequestInterceptor(
+            userAgent = BuildConfig.USER_AGENT,
+            apiEndpoint = BuildConfig.API_ENDPOINT,
+            apiKey = BuildConfig.API_KEY
+        )
+
+        val builder = OkHttpClient.Builder()
+            .addInterceptor(interceptor)
+
+        if (BuildConfig.DEBUG) {
+            builder.addInterceptor(HttpLoggingInterceptor().setLevel(HttpLoggingInterceptor.Level.BODY))
+        }
+
+        return builder.build()
     }
 
     @Provides
     @Singleton
     fun provideRetrofit(okHttpClient: OkHttpClient): Retrofit {
+        val gson = GsonBuilder()
+            .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES) // snake_case
+            .create()
+
         return Retrofit.Builder()
             .baseUrl(BuildConfig.API_ENDPOINT)
             .client(okHttpClient)
-            .addConverterFactory(GsonConverterFactory.create())
+            .addConverterFactory(GsonConverterFactory.create(gson))
             .build()
     }
 

app/src/main/java/eu/m724/chatapp/api/AiApiRequestInterceptor.kt

@@ -0,0 +1,21 @@
+package eu.m724.chatapp.api
+
+import okhttp3.Interceptor
+import okhttp3.Response
+
+class AiApiRequestInterceptor(
+    private val userAgent: String,
+    private val apiEndpoint: String,
+    private val apiKey: String
+) : Interceptor {
+    override fun intercept(chain: Interceptor.Chain): Response {
+        val builder = chain.request().newBuilder()
+            .header("User-Agent", userAgent)
+
+        if (chain.request().url.toString().startsWith(apiEndpoint)) {
+            builder.header("Authorization", "Bearer $apiKey")
+        }
+
+        return chain.proceed(builder.build())
+    }
+}

app/src/main/java/eu/m724/chatapp/api/AiApiService.kt

@@ -1,10 +1,17 @@
 package eu.m724.chatapp.api
 
-import eu.m724.chatapp.api.response.LanguageModelsResponse
+import eu.m724.chatapp.api.data.request.ChatCompletionRequest
+import eu.m724.chatapp.api.data.response.ChatCompletionResponse
+import eu.m724.chatapp.api.data.response.LanguageModelsResponse
 import retrofit2.Response
+import retrofit2.http.Body
 import retrofit2.http.GET
+import retrofit2.http.POST
 
 interface AiApiService {
     @GET("models?detailed=true")
     suspend fun getModels(): Response<LanguageModelsResponse>
+
+    @POST("chat/completions")
+    suspend fun chatComplete(@Body body: ChatCompletionRequest): Response<ChatCompletionResponse>
 }

app/src/main/java/eu/m724/chatapp/api/data/ChatMessage.kt

@@ -0,0 +1,12 @@
+package eu.m724.chatapp.api.data
+
+data class ChatMessage(
+    val role: Role,
+    val content: String
+) {
+    enum class Role {
+        SYSTEM,
+        USER,
+        ASSISTANT
+    }
+}

app/src/main/java/eu/m724/chatapp/api/data/request/ChatCompletionRequest.kt

@@ -0,0 +1,57 @@
+package eu.m724.chatapp.api.data.request
+
+import eu.m724.chatapp.api.data.ChatMessage
+
+data class ChatCompletionRequest(
+    /**
+     * The model ID
+     */
+    val model: String,
+
+    /**
+     * The messages in the current chat. Usually a user message is the last one if making a request.
+     */
+    val messages: List<ChatMessage>,
+
+    /**
+     * Controls the "creativity" of the model.
+     * Read more: https://www.iguazio.com/glossary/llm-temperature/
+     */
+    val temperature: Float,
+
+    /**
+     * The maximum amount of tokens to generate
+     */
+    val maxTokens: Int,
+
+    /**
+     * Controls the repetition of words in the generated text.
+     * Applies an incremental penalty, depending on how many times a token appears in the text.
+     *
+     * Read more: https://www.promptitude.io/glossary/frequency-penalty
+     * @see presencePenalty
+     */
+    val frequencyPenalty: Float,
+
+    /**
+     * Controls the repetition of words in the generated text.
+     * Applies a constant penalty, no matter how many times a token appears in the text.
+     *
+     * Read more: https://www.promptitude.io/glossary/frequency-penalty
+     * @see frequencyPenalty
+     */
+    val presencePenalty: Float
+) {
+    init {
+        require(temperature >= 0.0) { "temperature must be at least 0.0" }
+        require(temperature <= 2.0) { "temperature must be at most 2.0" }
+
+        require(maxTokens >= 0) { "maxTokens must be at least 0. If you don't want a limit here, use Int.MAX_VALUE"}
+
+        require(frequencyPenalty >= -2.0) { "frequencyPenalty must be at least -2.0" }
+        require(frequencyPenalty <= 2.0) { "frequencyPenalty must be at most 2.0" }
+
+        require(presencePenalty >= -2.0) { "presencePenalty must be at least -2.0" }
+        require(presencePenalty <= 2.0) { "presencePenalty must be at most 2.0" }
+    }
+}

app/src/main/java/eu/m724/chatapp/api/data/response/ChatCompletionResponse.kt

@@ -0,0 +1,80 @@
+package eu.m724.chatapp.api.data.response
+
+import com.google.gson.annotations.JsonAdapter
+import com.google.gson.annotations.SerializedName
+import eu.m724.chatapp.api.data.ChatMessage
+import eu.m724.chatapp.api.serialize.EpochSecondToLocalDateTimeDeserializer
+import java.time.LocalDateTime
+
+data class ChatCompletionResponse(
+    /**
+     * Request ID
+     */
+    val id: String,
+
+    /**
+     * Request time
+     */
+    @SerializedName("created")
+    @JsonAdapter(EpochSecondToLocalDateTimeDeserializer::class)
+    val createdAt: LocalDateTime,
+
+    /**
+     * Completion choices. Usually has only one element.
+     */
+    val choices: List<CompletionChoice>,
+
+    /**
+     * The cost (in tokens) of this completion
+     */
+    @SerializedName("usage")
+    val tokenUsage: CompletionTokenUsage
+)
+
+data class CompletionChoice(
+    val index: Int,
+
+    /**
+     * The generated message
+     */
+    val message: ChatMessage,
+
+    /**
+     * The reason why generating the response has stopped
+     */
+    val finishReason: CompletionFinishReason
+)
+
+enum class CompletionFinishReason {
+    /**
+     * The response has stopped, because the model said so
+     */
+    STOP,
+
+    /**
+     * The response has stopped, because it got too long
+     */
+    LENGTH,
+
+    /**
+     * The response has stopped, because the content got flagged
+     */
+    CONTENT_FILTER
+}
+
+data class CompletionTokenUsage(
+    /**
+     * The amount of tokens of the prompt
+     */
+    val promptTokens: Int,
+
+    /**
+     * The amount of tokens of the generated completion
+     */
+    val completionTokens: Int,
+
+    /**
+     * The total amount of tokens processed
+     */
+    val totalTokens: Int
+)

app/src/main/java/eu/m724/chatapp/api/data/response/LanguageModelsResponse.kt

@@ -1,4 +1,4 @@
-package eu.m724.chatapp.api.response
+package eu.m724.chatapp.api.data.response
 
 import com.google.gson.annotations.SerializedName
 

app/src/main/java/eu/m724/chatapp/api/serialize/EpochSecondToLocalDateTimeDeserializer.kt

@@ -0,0 +1,23 @@
+package eu.m724.chatapp.api.serialize
+
+import com.google.gson.JsonDeserializationContext
+import com.google.gson.JsonDeserializer
+import com.google.gson.JsonElement
+import com.google.gson.JsonParseException
+import java.lang.reflect.Type
+import java.time.LocalDateTime
+import java.time.ZoneOffset
+
+class EpochSecondToLocalDateTimeDeserializer : JsonDeserializer<LocalDateTime> {
+    override fun deserialize(
+        json: JsonElement?,
+        typeOfT: Type?,
+        context: JsonDeserializationContext?
+    ): LocalDateTime? {
+        json?.asLong?.let { timestamp ->
+            return LocalDateTime.ofEpochSecond(timestamp, 0, ZoneOffset.UTC)
+        }
+
+        throw JsonParseException("Error deserializing LocalDateTime from $json")
+    }
+}

gradle/libs.versions.toml

@@ -14,6 +14,7 @@ hilt = "2.56.2"
 ksp = "2.1.21-2.0.2"
 retrofit = "3.0.0"
 secrets = "2.0.1"
+loggingInterceptor = "4.12.0"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -36,6 +37,7 @@ hilt-android = { group = "com.google.dagger", name = "hilt-android", version.ref
 hilt-compiler = { group = "com.google.dagger", name = "hilt-compiler", version.ref = "hilt" }
 retrofit = { group = "com.squareup.retrofit2", name = "retrofit", version.ref = "retrofit" }
 retrofit-converter-gson = { group = "com.squareup.retrofit2", name = "converter-gson", version.ref = "retrofit"}
+logging-interceptor = { group = "com.squareup.okhttp3", name = "logging-interceptor", version.ref = "loggingInterceptor" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }