Add undo redo functionality. Move new game to navigation drawer

app/src/main/java/me/zobrist/tichucounter/BaseActivity.kt

@@ -73,17 +73,10 @@ abstract class BaseActivity : AppCompatActivity(),
     }
 
     private fun setLanguage(language: Language) {
-
-        val locale = when (language) {
-            Language.ENGLISH -> "en"
-            Language.GERMAN -> "de"
-            else -> null
-        }
-
         val currentLocale = AppCompatDelegate.getApplicationLocales()[0].toString()
 
-        if (locale != null && locale != currentLocale) {
-            val newLocale = LocaleListCompat.forLanguageTags(locale)
+        if (language.value != null && language.value != currentLocale) {
+            val newLocale = LocaleListCompat.forLanguageTags(language.value)
             AppCompatDelegate.setApplicationLocales(newLocale)
         }
     }

app/src/main/java/me/zobrist/tichucounter/MainActivity.kt

@@ -15,6 +15,7 @@ import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
+import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavDestination.Companion.hierarchy
 import androidx.navigation.NavGraph.Companion.findStartDestination
 import androidx.navigation.NavHostController
@@ -87,7 +88,11 @@ class MainActivity : BaseActivity() {
                 ) {
                     composable("counter") {
                         Counter(counterViewModel)
-                        mainViewModel.topBarActions = (listOf(undoAction, newGameAction))
+                        mainViewModel.topBarActions = (listOf(
+                            TopBarAction(Icons.Outlined.Undo, mainViewModel.isUndoActionActive) { mainViewModel.undoLastRound() },
+                            TopBarAction(Icons.Outlined.Redo, mainViewModel.isRedoActionActive) { mainViewModel.redoLastRound() }
+
+                        ))
                         mainViewModel.topBarIcon = Icons.Outlined.Menu
                         mainViewModel.topBarTitle = stringResource(R.string.app_name)
                         mainViewModel.topBarNavigationAction =
@@ -140,10 +145,10 @@ class MainActivity : BaseActivity() {
             },
             actions = {
                 actions.forEach {
-                    IconButton(onClick = { it.action() }) {
+                    IconButton(onClick = { it.action() }, enabled = it.isActive) {
                         Icon(
                             imageVector = it.imageVector,
-                            contentDescription = null
+                            contentDescription = null,
                         )
                     }
                 }
@@ -167,7 +172,40 @@ class MainActivity : BaseActivity() {
             drawerState = drawerState,
             drawerContent = {
                 ModalDrawerSheet {
-                    Spacer(Modifier.height(12.dp))
+
+                    Spacer(Modifier.height(20.dp))
+
+                    NavigationDrawerItem(
+                        icon = { Icon(Icons.Outlined.RestartAlt, contentDescription = null) },
+                        colors = NavigationDrawerItemDefaults.colors(
+                            unselectedContainerColor = MaterialTheme.colorScheme.secondaryContainer
+                        ),
+                        label = { Text(stringResource(R.string.newGame)) },
+                        selected = false,
+                        onClick = {
+                            scope.launch { drawerState.close() }
+                            mainViewModel.newGame()
+                            navController.navigate("counter") {
+                                // Pop up to the start destination of the graph to
+                                // avoid building up a large stack of destinations
+                                // on the back stack as users select items
+                                popUpTo(navController.graph.findStartDestination().id) {
+                                    saveState = true
+                                }
+                                // Avoid multiple copies of the same destination when
+                                // reselecting the same item
+                                launchSingleTop = true
+                                // Restore state when reselecting a previously selected item
+                                restoreState = true
+                            }
+                        },
+                        modifier = Modifier.padding(NavigationDrawerItemDefaults.ItemPadding)
+                    )
+
+                    Spacer(Modifier.height(20.dp))
+
+                    Divider()
+
                     items.forEach { screen ->
                         NavigationDrawerItem(
                             icon = { Icon(screen.icon, contentDescription = null) },
@@ -203,8 +241,4 @@ class MainActivity : BaseActivity() {
         object Settings : Screen("settings", Icons.Outlined.Settings, R.string.menu_settings)
 
     }
-
-    private val undoAction = TopBarAction(Icons.Outlined.Undo) { mainViewModel.undoLastRound() }
-    private val newGameAction = TopBarAction(Icons.Outlined.Add) { mainViewModel.newGame() }
-
 }

app/src/main/java/me/zobrist/tichucounter/domain/TopBarAction.kt

@@ -2,4 +2,4 @@ package me.zobrist.tichucounter.domain
 
 import androidx.compose.ui.graphics.vector.ImageVector
 
-class TopBarAction(val imageVector: ImageVector, val action: () -> Unit)
+class TopBarAction(val imageVector: ImageVector, val isActive: Boolean, val action: () -> Unit)

app/src/main/java/me/zobrist/tichucounter/repository/GameRepository.kt

@@ -2,6 +2,7 @@ package me.zobrist.tichucounter.repository
 
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.last
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import me.zobrist.tichucounter.data.Game
@@ -57,12 +58,20 @@ class GameRepository @Inject constructor(
         }
     }
 
-    suspend fun revertLastRound() {
+    suspend fun getLastRound(): Round? {
+        return try {
+            withContext(Dispatchers.IO) {
+                roundDao.getAllForGame(activeGame.uid).last()
+            }
+        } catch (_:NoSuchElementException) {
+            null
+        }
+    }
+    suspend fun deleteLastRound() {
         withContext(Dispatchers.IO) {
             try {
-                val lastRound = roundDao.getAllForGame(activeGame.uid).last()
-                roundDao.delete(lastRound)
-            } catch (_: NoSuchElementException) {
+                roundDao.delete(getLastRound()!!)
+            } catch (_: NullPointerException) {
             }
         }
     }

app/src/main/java/me/zobrist/tichucounter/ui/MainViewModel.kt

@@ -2,40 +2,84 @@ package me.zobrist.tichucounter.ui
 
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Menu
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.setValue
+import androidx.compose.runtime.*
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.launch
+import me.zobrist.tichucounter.data.Round
+import me.zobrist.tichucounter.data.RoundDao
 import me.zobrist.tichucounter.domain.NavigationAction
 import me.zobrist.tichucounter.domain.TopBarAction
 import me.zobrist.tichucounter.repository.GameRepository
+import java.util.NoSuchElementException
 import javax.inject.Inject
 
 @HiltViewModel
-class MainViewModel @Inject constructor(private val gameRepository: GameRepository) : ViewModel() {
+class MainViewModel @Inject constructor(private val gameRepository: GameRepository, roundDao: RoundDao) : ViewModel() {
+
+    private var redoRounds = mutableStateListOf<Round>()
+    private var expectedRoundCount = 0
 
     var topBarTitle by mutableStateOf("")
     var topBarActions by mutableStateOf(emptyList<TopBarAction>())
     var topBarIcon by mutableStateOf(Icons.Filled.Menu)
-
-
+    var isUndoActionActive by mutableStateOf(false)
     var topBarNavigationAction by mutableStateOf(NavigationAction {})
 
+    val isRedoActionActive: Boolean
+        get() = redoRounds.isNotEmpty()
+
+    init {
+        viewModelScope.launch {
+            roundDao.getForActiveGame().collect() {
+                isUndoActionActive = it.isNotEmpty()
+
+                if(expectedRoundCount != it.count()) {
+                    redoRounds.clear()
+                }
+
+                expectedRoundCount = it.count()
+            }
+        }
+    }
+
+
     fun onNavigateClicked() {
         topBarNavigationAction.aciton()
     }
 
     fun undoLastRound() {
         viewModelScope.launch {
-            gameRepository.revertLastRound()
+            val round = gameRepository.getLastRound()
+            if (round != null) {
+                redoRounds.add(round)
+                expectedRoundCount--
+                gameRepository.deleteLastRound()
+            }
         }
     }
 
+    fun redoLastRound() {
+        viewModelScope.launch {
+            try {
+                val round = redoRounds.last()
+                redoRounds.remove(round)
+                expectedRoundCount++
+                gameRepository.addRoundToActiveGame(round.scoreA, round.scoreB)
+            }catch (_: NoSuchElementException)
+            {
+            }
+        }
+    }
+
+    fun clearRedoList() {
+        redoRounds.clear()
+    }
+
     fun newGame() {
         viewModelScope.launch {
+            redoRounds.clear()
             gameRepository.newGame()
         }
     }

app/src/main/res/values-de/strings.xml

@@ -24,5 +24,6 @@
     <string name="submit">Übermitteln</string>
     <string name="on">Ein</string>
     <string name="off">Aus</string>
+    <string name="newGame">Neues Spiel</string>
 
 </resources>

app/src/main/res/values/strings.xml

@@ -21,8 +21,6 @@
     <string name="dark">Dark</string>
     <string name="display">Display</string>
     <string name="settings">Settings</string>
-    <string name="nav_header_subtitle">app@zobrist.me</string>
-    <string name="nav_header_desc">Navigation header</string>
 
     <string name="menu_counter">Counter</string>
     <string name="menu_history">History</string>
@@ -30,7 +28,7 @@
     <string name="activate">Activate</string>
     <string name="delete">Delete</string>
     <string name="submit">Submit</string>
-    <string name="title_activity_main">MainActivity</string>
     <string name="on">On</string>
     <string name="off">Off</string>
+    <string name="newGame">New Game</string>
 </resources>