feat: Implement basic chat screen and ViewModel logic

This commit introduces the initial implementation of the chat screen and its associated ViewModel.

Key changes:
- `ChatScreen.kt`: Added a basic UI with a text input field, send button, and a list to display messages.
- `ChatViewModel.kt`:
    - Implemented `ChatState` to hold the list of chat messages.
    - Added `saveChat` function to save new messages using `SaveChatUseCase`.
    - Added `observeAllChats` function to observe chat messages for a given conversation ID using `ObserveAllChatsUseCase`.
- `EclairDatabase.kt`: Updated `EclairDatabase` to use an internal `expect object EclairDatabaseCtor` for construction, replacing the separate `EclairDatabaseConstructor.kt` file.
- Database Builders (`iosMain` and `desktopMain`):
    - Configured `BundledSQLiteDriver` for both iOS and Desktop.
    - Set query coroutine context to `Dispatchers.IO` for Desktop.
    - Removed `setQueryCoroutineContext(Dispatchers.IO)` for iOS as it's not needed with `BundledSQLiteDriver`.
- `EclairApp.kt`: Updated to display the `ChatScreen`.
- `build.gradle.kts`:
    - Enabled `-Xexpect-actual-classes` compiler option for JVM targets.
    - Simplified KSP dependency declaration to `ksp(libs.room.compiler)`.

Removed:
- `EclairDatabaseConstructor.kt`: Its functionality is now integrated into `EclairDatabase.kt`.

Author: judahben149

composeApp/build.gradle.kts

@@ -31,7 +31,23 @@ kotlin {
         }
     }
 
-    jvm("desktop")
+    jvm("desktop") {
+        @OptIn(ExperimentalKotlinGradlePluginApi::class)
+        compilerOptions {
+            jvmTarget.set(JvmTarget.JVM_11)
+            freeCompilerArgs.add("-Xexpect-actual-classes")
+        }
+    }
+
+    targets.configureEach {
+        compilations.configureEach {
+            compileTaskProvider.configure {
+                compilerOptions {
+                    freeCompilerArgs.add("-Xexpect-actual-classes")
+                }
+            }
+        }
+    }
 
     sourceSets {
         val desktopMain by getting
@@ -100,10 +116,7 @@ room {
 
 dependencies {
     debugImplementation(compose.uiTooling)
-    add("kspAndroid", libs.room.compiler)
-    add("kspIosSimulatorArm64", libs.room.compiler)
-    add("kspIosX64", libs.room.compiler)
-    add("kspIosArm64", libs.room.compiler)
+    ksp(libs.room.compiler)
 }
 
 compose.desktop {

composeApp/src/commonMain/kotlin/com/judahben149/eclair/EclairApp.kt

@@ -2,12 +2,13 @@ package com.judahben149.eclair
 
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
+import com.judahben149.eclair.presentation.screens.chat.ChatScreen
 import org.jetbrains.compose.ui.tooling.preview.Preview
 
 @Composable
 @Preview
 fun EclairApp() {
     MaterialTheme {
-
+        ChatScreen()
     }
 }

composeApp/src/commonMain/kotlin/com/judahben149/eclair/data/local/EclairDatabase.kt

@@ -3,11 +3,14 @@ package com.judahben149.eclair.data.local
 import androidx.room.ConstructedBy
 import androidx.room.Database
 import androidx.room.RoomDatabase
+import androidx.room.RoomDatabaseConstructor
 import com.judahben149.eclair.data.local.dto.ChatMessageDto
 import com.judahben149.eclair.data.local.dto.ConversationDto
 
-@ConstructedBy(EclairDatabaseConstructor::class)
+internal expect object EclairDatabaseCtor : RoomDatabaseConstructor<EclairDatabase>
+
 @Database(entities = [ConversationDto::class, ChatMessageDto::class], version = 1)
+@ConstructedBy(EclairDatabaseCtor::class)
 abstract class EclairDatabase: RoomDatabase() {
     abstract fun chatDao(): ChatDao
 }

composeApp/src/commonMain/kotlin/com/judahben149/eclair/data/local/EclairDatabaseConstructor.kt

@@ -1,11 +1,70 @@
 package com.judahben149.eclair.presentation.screens.chat
 
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Button
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextField
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.unit.dp
+import com.judahben149.eclair.domain.enums.MessageOrigin
+import com.judahben149.eclair.domain.model.ChatMessage
 import org.jetbrains.compose.ui.tooling.preview.Preview
+import org.koin.compose.viewmodel.koinViewModel
 
 @Composable
 fun ChatScreen() {
+    val viewModel = koinViewModel<ChatViewModel>()
+    val state by viewModel.state.collectAsState()
 
+    ChatContent(state) {
+        viewModel.saveChat(
+            ChatMessage(
+                id = "",
+                conversationId = "conversationId",
+                message = it,
+                origin = MessageOrigin.SENT,
+                timestamp = 0
+            )
+        )
+    }
+}
+
+@Composable
+fun ChatContent(state: ChatState, onSendMessage: (String) -> Unit) {
+    val (text, setText) = remember { mutableStateOf("") }
+
+    Column(modifier = androidx.compose.ui.Modifier.fillMaxWidth()) {
+        Column(modifier = androidx.compose.ui.Modifier.weight(1f)) {
+            state.chats.forEach { chat ->
+                Text(
+                    text = chat.message,
+                    modifier = androidx.compose.ui.Modifier.padding(8.dp)
+                )
+            }
+        }
+
+        Row(modifier = androidx.compose.ui.Modifier.fillMaxWidth().padding(8.dp)) {
+            TextField(
+                value = text,
+                onValueChange = setText,
+                label = { Text("New Chat") },
+                modifier = androidx.compose.ui.Modifier.weight(1f).padding(end = 8.dp)
+            )
+            Button(onClick = {
+                if (text.isNotBlank()) {
+                    onSendMessage(text)
+                    setText("")
+                }
+            }) { Text("Send") }
+        }
+    }
 }
 
 

composeApp/src/commonMain/kotlin/com/judahben149/eclair/presentation/screens/chat/ChatScreen.kt

@@ -1,13 +1,41 @@
 package com.judahben149.eclair.presentation.screens.chat
 
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.judahben149.eclair.domain.model.ChatMessage
 import com.judahben149.eclair.domain.usecase.ObserveAllChatsUseCase
 import com.judahben149.eclair.domain.usecase.SaveChatUseCase
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.launch
 
 class ChatViewModel(
     private val saveChatUseCase: SaveChatUseCase,
     private val observeAllChatsUseCase: ObserveAllChatsUseCase
 ): ViewModel() {
 
+    private val _state = MutableStateFlow(ChatState())
+    val state = _state.asStateFlow()
 
-}
+    init {
+        observeAllChats("conversationId")
+    }
+
+    fun saveChat(chat: ChatMessage) {
+        viewModelScope.launch {
+            saveChatUseCase(chat)
+        }
+    }
+
+    fun observeAllChats(conversationId: String) {
+        viewModelScope.launch {
+            observeAllChatsUseCase(conversationId).collect {
+                _state.value = _state.value.copy(chats = it)
+            }
+        }
+    }
+}
+
+data class ChatState(
+    val chats: List<ChatMessage> = emptyList()
+)

composeApp/src/commonMain/kotlin/com/judahben149/eclair/presentation/screens/chat/ChatViewModel.kt

@@ -1,12 +1,16 @@
 package com.judahben149.eclair.data.local
 
 import androidx.room.Room
+import androidx.sqlite.driver.bundled.BundledSQLiteDriver
+import kotlinx.coroutines.Dispatchers
 import java.io.File
 
 fun getEclairDatabaseBuilder(): EclairDatabase {
     val dbFile = File(System.getProperty("java.io.tmpdir"), "eclair.db")
-
     return Room.databaseBuilder<EclairDatabase>(
         name = dbFile.absolutePath,
-    ).build()
+    )
+        .setDriver(BundledSQLiteDriver())
+        .setQueryCoroutineContext(Dispatchers.IO)
+        .build()
 }

composeApp/src/desktopMain/kotlin/com/judahben149/eclair/data/local/DatabaseBuilder.kt

@@ -15,6 +15,6 @@ fun getEclairDatabaseBuilder(): EclairDatabase {
 //        factory = { EclairDatabase::class.instantiateImpl()}
     )
         .setDriver(BundledSQLiteDriver())
-        .setQueryCoroutineContext(Dispatchers.IO)
+//        .setQueryCoroutineContext(Dispatchers.IO)
         .build()
 }