fix: separate local create validation from server errors in board detail viewmodel

app/src/main/java/space/hackenslacker/kanbn4droid/app/boarddetail/BoardDetailViewModel.kt

@@ -14,6 +14,8 @@ import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import space.hackenslacker.kanbn4droid.app.boards.BoardsApiResult
 
+private const val ADD_CARD_DISABLED_MESSAGE = "Create a list first to add cards."
+
 data class BoardDetailUiState(
     val isInitialLoading: Boolean = false,
     val isRefreshing: Boolean = false,
@@ -34,7 +36,9 @@ data class BoardDetailUiState(
     val isFilterDialogOpen: Boolean = false,
     val isSearchDialogOpen: Boolean = false,
     val addListTitleDraft: String = "",
+    val addListTitleError: String? = null,
     val addCardTitleDraft: String = "",
+    val addCardTitleError: String? = null,
     val addCardDescriptionDraft: String = "",
     val addCardDueDate: LocalDate? = null,
     val addCardSelectedTagIds: Set<String> = emptySet(),
@@ -43,7 +47,7 @@ data class BoardDetailUiState(
         get() = boardDetail?.lists?.isNotEmpty() == true
 
     val addCardDisabledMessage: String?
-        get() = if (canAddCard) null else "Add a list before creating cards."
+        get() = if (canAddCard) null else ADD_CARD_DISABLED_MESSAGE
 
     val filteredBoardDetail: BoardDetail?
         get() = boardDetail?.withFilteredCards(
@@ -198,12 +202,18 @@ class BoardDetailViewModel(
             it.copy(
                 isFabChooserOpen = false,
                 isAddListDialogOpen = true,
+                addListTitleError = null,
             )
         }
     }
 
     fun updateAddListTitle(title: String) {
-        _uiState.update { it.copy(addListTitleDraft = title) }
+        _uiState.update {
+            it.copy(
+                addListTitleDraft = title,
+                addListTitleError = null,
+            )
+        }
     }
 
     fun cancelAddListDialog() {
@@ -211,6 +221,7 @@ class BoardDetailViewModel(
             it.copy(
                 isAddListDialogOpen = false,
                 addListTitleDraft = "",
+                addListTitleError = null,
             )
         }
     }
@@ -223,26 +234,19 @@ class BoardDetailViewModel(
         val detail = snapshot.boardDetail ?: return
         val title = snapshot.addListTitleDraft.trim()
         if (title.isBlank()) {
-            viewModelScope.launch {
+            setAddListLocalValidationError("List title is required")
-                _events.emit(BoardDetailUiEvent.ShowServerError("List title is required"))
-            }
             return
         }
         val expectedIndex = detail.lists.size
 
         viewModelScope.launch {
-            _uiState.update { it.copy(isMutating = true) }
+            beginCreateListMutation()
             when (val result = repository.createList(detail.id, title)) {
                 is BoardsApiResult.Success -> {
-                    _uiState.update {
+                    closeAddListDialogAndResetDrafts()
-                        it.copy(
-                            isAddListDialogOpen = false,
-                            addListTitleDraft = "",
-                        )
-                    }
                     when (val reload = reloadDetailAndReconcile()) {
                         is BoardsApiResult.Success -> {
-                            _uiState.update { it.copy(isMutating = false) }
+                            endMutation()
                             val warning = verifyCreatedList(result.value.publicId, expectedIndex, reload.value)
                             if (warning != null) {
                                 _events.emit(BoardDetailUiEvent.ShowWarning(warning))
@@ -250,18 +254,14 @@ class BoardDetailViewModel(
                         }
 
                         is BoardsApiResult.Failure -> {
-                            _uiState.update { it.copy(isMutating = false) }
+                            endMutation()
-                            _events.emit(
+                            emitRefreshFailureWarning()
-                                BoardDetailUiEvent.ShowWarning(
-                                    "Changes applied, but refresh failed. Pull to refresh.",
-                                ),
-                            )
                         }
                     }
                 }
 
                 is BoardsApiResult.Failure -> {
-                    _uiState.update { it.copy(isMutating = false) }
+                    endMutation()
                     _events.emit(BoardDetailUiEvent.ShowServerError(result.message))
                 }
             }
@@ -279,12 +279,18 @@ class BoardDetailViewModel(
             it.copy(
                 isFabChooserOpen = false,
                 isAddCardDialogOpen = true,
+                addCardTitleError = null,
             )
         }
     }
 
     fun updateAddCardTitle(title: String) {
-        _uiState.update { it.copy(addCardTitleDraft = title) }
+        _uiState.update {
+            it.copy(
+                addCardTitleDraft = title,
+                addCardTitleError = null,
+            )
+        }
     }
 
     fun updateAddCardDescription(description: String) {
@@ -327,14 +333,12 @@ class BoardDetailViewModel(
         val currentList = detail.lists.getOrNull(snapshot.currentPageIndex) ?: return
         val title = snapshot.addCardTitleDraft.trim()
         if (title.isBlank()) {
-            viewModelScope.launch {
+            setAddCardLocalValidationError("Card title is required")
-                _events.emit(BoardDetailUiEvent.ShowServerError("Card title is required"))
-            }
             return
         }
 
         viewModelScope.launch {
-            _uiState.update { it.copy(isMutating = true) }
+            beginCreateCardMutation()
             when (
                 val result = repository.createCard(
                     listPublicId = currentList.id,
@@ -345,12 +349,10 @@ class BoardDetailViewModel(
                 )
             ) {
                 is BoardsApiResult.Success -> {
-                    _uiState.update {
+                    closeAddCardDialogAndResetDrafts()
-                        it.resetAddCardDrafts().copy(isAddCardDialogOpen = false)
-                    }
                     when (val reload = reloadDetailAndReconcile()) {
                         is BoardsApiResult.Success -> {
-                            _uiState.update { it.copy(isMutating = false) }
+                            endMutation()
                             val warning = verifyCreatedCard(
                                 createdCardId = result.value.publicId,
                                 targetListId = currentList.id,
@@ -362,18 +364,14 @@ class BoardDetailViewModel(
                         }
 
                         is BoardsApiResult.Failure -> {
-                            _uiState.update { it.copy(isMutating = false) }
+                            endMutation()
-                            _events.emit(
+                            emitRefreshFailureWarning()
-                                BoardDetailUiEvent.ShowWarning(
-                                    "Changes applied, but refresh failed. Pull to refresh.",
-                                ),
-                            )
                         }
                     }
                 }
 
                 is BoardsApiResult.Failure -> {
-                    _uiState.update { it.copy(isMutating = false) }
+                    endMutation()
                     _events.emit(BoardDetailUiEvent.ShowServerError(result.message))
                 }
             }
@@ -768,6 +766,52 @@ class BoardDetailViewModel(
         return if (actualIndex != 0) CREATE_CARD_PLACEMENT_WARNING else null
     }
 
+    private fun setAddListLocalValidationError(message: String) {
+        _uiState.update { it.copy(addListTitleError = message) }
+    }
+
+    private fun setAddCardLocalValidationError(message: String) {
+        _uiState.update { it.copy(addCardTitleError = message) }
+    }
+
+    private fun beginCreateListMutation() {
+        _uiState.update {
+            it.copy(
+                isMutating = true,
+                addListTitleError = null,
+            )
+        }
+    }
+
+    private fun beginCreateCardMutation() {
+        _uiState.update {
+            it.copy(
+                isMutating = true,
+                addCardTitleError = null,
+            )
+        }
+    }
+
+    private fun closeAddListDialogAndResetDrafts() {
+        _uiState.update { it.resetAddListDrafts().copy(isAddListDialogOpen = false) }
+    }
+
+    private fun closeAddCardDialogAndResetDrafts() {
+        _uiState.update { it.resetAddCardDrafts().copy(isAddCardDialogOpen = false) }
+    }
+
+    private fun endMutation() {
+        _uiState.update { it.copy(isMutating = false) }
+    }
+
+    private suspend fun emitRefreshFailureWarning() {
+        _events.emit(
+            BoardDetailUiEvent.ShowWarning(
+                "Changes applied, but refresh failed. Pull to refresh.",
+            ),
+        )
+    }
+
     private companion object {
         const val CREATE_LIST_PLACEMENT_WARNING =
             "List created, but server ordering differed. Pull to refresh if needed."
@@ -797,12 +841,20 @@ class BoardDetailViewModel(
 private fun BoardDetailUiState.resetAddCardDrafts(): BoardDetailUiState {
     return copy(
         addCardTitleDraft = "",
+        addCardTitleError = null,
         addCardDescriptionDraft = "",
         addCardDueDate = null,
         addCardSelectedTagIds = emptySet(),
     )
 }
 
+private fun BoardDetailUiState.resetAddListDrafts(): BoardDetailUiState {
+    return copy(
+        addListTitleDraft = "",
+        addListTitleError = null,
+    )
+}
+
 private fun BoardDetail.withFilteredCards(tagFilterIds: Set<String>, titleQuery: String): BoardDetail {
     val normalizedTitleQuery = titleQuery.trim()
     if (tagFilterIds.isEmpty() && normalizedTitleQuery.isEmpty()) {

app/src/test/java/space/hackenslacker/kanbn4droid/app/boarddetail/BoardDetailViewModelTest.kt

@@ -10,6 +10,7 @@ import kotlinx.coroutines.test.advanceUntilIdle
 import kotlinx.coroutines.test.resetMain
 import kotlinx.coroutines.test.runTest
 import kotlinx.coroutines.test.setMain
+import kotlinx.coroutines.withTimeoutOrNull
 import java.time.LocalDate
 import org.junit.After
 import org.junit.Assert.assertEquals
@@ -71,7 +72,7 @@ class BoardDetailViewModelTest {
         viewModel.openAddCardDialog()
 
         assertFalse(viewModel.uiState.value.canAddCard)
-        assertEquals("Add a list before creating cards.", viewModel.uiState.value.addCardDisabledMessage)
+        assertEquals("Create a list first to add cards.", viewModel.uiState.value.addCardDisabledMessage)
         assertFalse(viewModel.uiState.value.isAddCardDialogOpen)
     }
 
@@ -207,12 +208,11 @@ class BoardDetailViewModelTest {
     }
 
     @Test
-    fun createList_blankTitle_rejectsBeforeRepositoryCall() = runTest {
+    fun createList_blankTitle_setsLocalError_andRejectsBeforeRepositoryCall() = runTest {
         val repository = FakeBoardDetailDataSource(
             boardDetailResults = ArrayDeque(listOf(BoardsApiResult.Success(detailWithSingleList()))),
         )
         val viewModel = newLoadedViewModel(this, repository)
-        val eventDeferred = async { viewModel.events.first() }
 
         viewModel.openAddListDialog()
         viewModel.updateAddListTitle("   ")
@@ -220,18 +220,21 @@ class BoardDetailViewModelTest {
         advanceUntilIdle()
 
         assertEquals(0, repository.createListCalls)
-        val event = eventDeferred.await()
+        assertEquals("List title is required", viewModel.uiState.value.addListTitleError)
-        assertTrue(event is BoardDetailUiEvent.ShowServerError)
+        assertTrue(viewModel.uiState.value.isAddListDialogOpen)
-        assertEquals("List title is required", (event as BoardDetailUiEvent.ShowServerError).message)
+        val event = withTimeoutOrNull(50) { viewModel.events.first() }
+        assertNull(event)
+
+        viewModel.updateAddListTitle("Valid")
+        assertNull(viewModel.uiState.value.addListTitleError)
     }
 
     @Test
-    fun createCard_blankTitle_rejectsBeforeRepositoryCall() = runTest {
+    fun createCard_blankTitle_setsLocalError_andRejectsBeforeRepositoryCall() = runTest {
         val repository = FakeBoardDetailDataSource(
             boardDetailResults = ArrayDeque(listOf(BoardsApiResult.Success(detailWithSingleList()))),
         )
         val viewModel = newLoadedViewModel(this, repository)
-        val eventDeferred = async { viewModel.events.first() }
 
         viewModel.openAddCardDialog()
         viewModel.updateAddCardTitle("   ")
@@ -239,9 +242,13 @@ class BoardDetailViewModelTest {
         advanceUntilIdle()
 
         assertEquals(0, repository.createCardCalls)
-        val event = eventDeferred.await()
+        assertEquals("Card title is required", viewModel.uiState.value.addCardTitleError)
-        assertTrue(event is BoardDetailUiEvent.ShowServerError)
+        assertTrue(viewModel.uiState.value.isAddCardDialogOpen)
-        assertEquals("Card title is required", (event as BoardDetailUiEvent.ShowServerError).message)
+        val event = withTimeoutOrNull(50) { viewModel.events.first() }
+        assertNull(event)
+
+        viewModel.updateAddCardTitle("Valid")
+        assertNull(viewModel.uiState.value.addCardTitleError)
     }
 
     @Test