android: add basic screens

composeApp/src/androidMain/kotlin/su/reya/coop/App.kt

@@ -1,48 +1,83 @@
 package su.reya.coop
 
-import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.foundation.Image
-import androidx.compose.foundation.background
-import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.safeContentPadding
-import androidx.compose.material3.Button
+import android.content.Context
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.Text
-import androidx.compose.runtime.*
-import androidx.compose.ui.Alignment
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.tooling.preview.Preview
-import org.jetbrains.compose.resources.painterResource
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.platform.LocalContext
+import androidx.datastore.core.DataStore
+import androidx.datastore.preferences.core.Preferences
+import androidx.datastore.preferences.core.booleanPreferencesKey
+import androidx.datastore.preferences.core.edit
+import androidx.datastore.preferences.preferencesDataStore
+import androidx.navigation.compose.NavHost
+import androidx.navigation.compose.composable
+import androidx.navigation.compose.rememberNavController
+import androidx.navigation.toRoute
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
 
-import coop.composeapp.generated.resources.Res
-import coop.composeapp.generated.resources.compose_multiplatform
+private val Context.dataStore: DataStore<Preferences> by preferencesDataStore(name = "settings")
+private val FIRST_TIME_KEY = booleanPreferencesKey("first_time")
 
 @Composable
-@Preview
 fun App() {
     MaterialTheme {
-        var showContent by remember { mutableStateOf(false) }
-        Column(
-            modifier = Modifier
-                .background(MaterialTheme.colorScheme.primaryContainer)
-                .safeContentPadding()
-                .fillMaxSize(),
-            horizontalAlignment = Alignment.CenterHorizontally,
-        ) {
-            Button(onClick = { showContent = !showContent }) {
-                Text("Click me!")
+        val context = LocalContext.current
+        val scope = rememberCoroutineScope()
+        val navController = rememberNavController()
+
+        val isFirstTimeFlow = remember {
+            context.dataStore.data.map { preferences ->
+                preferences[FIRST_TIME_KEY] ?: true
             }
-            AnimatedVisibility(showContent) {
-                val greeting = remember { Greeting().greet() }
-                Column(
-                    modifier = Modifier.fillMaxWidth(),
-                    horizontalAlignment = Alignment.CenterHorizontally,
-                ) {
-                    Image(painterResource(Res.drawable.compose_multiplatform), null)
-                    Text("Compose: $greeting")
-                }
+        }
+        val isFirstTime by isFirstTimeFlow.collectAsState(initial = null)
+
+        if (isFirstTime == null) {
+            // Loading state
+            return@MaterialTheme
+        }
+
+        NavHost(
+            navController = navController,
+            startDestination = if (isFirstTime == true) Screen.Welcome else Screen.Home
+        ) {
+            composable<Screen.Welcome> { backStackEntry ->
+                WelcomeScreen(onContinue = {
+                    scope.launch {
+                        context.dataStore.edit { settings ->
+                            settings[FIRST_TIME_KEY] = false
+                        }
+                        navController.navigate(Screen.Home) {
+                            popUpTo<Screen.Welcome> { inclusive = true }
+                        }
+                    }
+                })
+            }
+            composable<Screen.Home> { backStackEntry ->
+                HomeScreen(
+                    onOpenChat = { id -> navController.navigate(Screen.Chat(id)) }
+                )
+            }
+            composable<Screen.Chat> { backStackEntry ->
+                val chat: Screen.Chat = backStackEntry.toRoute()
+                ChatScreen(id = chat.id)
+            }
+            composable<Screen.Onboarding> { backStackEntry ->
+                OnboardingScreen(
+                    onOpenImport = { navController.navigate(Screen.Import) },
+                    onOpenNew = { navController.navigate(Screen.New) }
+                )
+            }
+            composable<Screen.Import> { backStackEntry ->
+                ImportScreen()
+            }
+            composable<Screen.New> { backStackEntry ->
+                NewScreen()
             }
         }
     }

composeApp/src/androidMain/kotlin/su/reya/coop/MainActivity.kt

@@ -32,7 +32,6 @@ class MainActivity : ComponentActivity() {
         setContent {
             App()
         }
-
     }
 }
 

composeApp/src/androidMain/kotlin/su/reya/coop/Screens.kt

@@ -0,0 +1,98 @@
+package su.reya.coop
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.height
+import androidx.compose.material3.Button
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import kotlinx.serialization.Serializable
+
+sealed interface Screen {
+    @Serializable
+    data object Welcome : Screen
+
+    @Serializable
+    data object Home : Screen
+
+    @Serializable
+    data class Chat(val id: String) : Screen
+
+    @Serializable
+    data object Onboarding : Screen
+
+    @Serializable
+    data object Import : Screen
+
+    @Serializable
+    data object New : Screen
+}
+
+@Composable
+fun WelcomeScreen(onContinue: () -> Unit) {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Column(horizontalAlignment = Alignment.CenterHorizontally) {
+            Text("Welcome Screen")
+            Spacer(modifier = Modifier.height(16.dp))
+            Button(onClick = onContinue) {
+                Text("Get Started")
+            }
+        }
+    }
+}
+
+@Composable
+fun HomeScreen(onOpenChat: (String) -> Unit) {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Column(horizontalAlignment = Alignment.CenterHorizontally) {
+            Text("Home Screen")
+            Spacer(modifier = Modifier.height(16.dp))
+            Button(onClick = { onOpenChat("123") }) {
+                Text("Open Chat 123")
+            }
+        }
+    }
+}
+
+@Composable
+fun ChatScreen(id: String) {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Text("Chat Screen (ID: $id)")
+    }
+}
+
+@Composable
+fun OnboardingScreen(onOpenImport: () -> Unit, onOpenNew: () -> Unit) {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Column(horizontalAlignment = Alignment.CenterHorizontally) {
+            Text("Onboarding Screen")
+            Spacer(modifier = Modifier.height(16.dp))
+            Button(onClick = onOpenImport) {
+                Text("Import")
+            }
+            Spacer(modifier = Modifier.height(8.dp))
+            Button(onClick = onOpenNew) {
+                Text("New")
+            }
+        }
+    }
+}
+
+@Composable
+fun ImportScreen() {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Text("Import Screen")
+    }
+}
+
+@Composable
+fun NewScreen() {
+    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Text("New Screen")
+    }
+}