feat(new reviewer): answer timer

AnkiDroid/src/main/java/com/ichi2/anki/ui/windows/reviewer/AnswerTimer.kt

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2025 Brayan Oliveira <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.ichi2.anki.ui.windows.reviewer
+
+import android.content.Context
+import android.os.Parcelable
+import android.os.SystemClock
+import android.util.AttributeSet
+import android.widget.Chronometer
+import androidx.appcompat.widget.ThemeUtils
+import com.ichi2.anki.R
+import kotlinx.parcelize.Parcelize
+
+/**
+ * Improved version of a [Chronometer] aimed at handling Anki Decks' `Timer` configurations.
+ *
+ * Compared to a default [Chronometer], it can:
+ * - Restore its status after configuration changes
+ * - Stop the timer after [limitInMs] is reached.
+ */
+class AnswerTimer(
+    context: Context,
+    attributeSet: AttributeSet?,
+) : Chronometer(context, attributeSet) {
+    var limitInMs = Int.MAX_VALUE
+    private var elapsedMillisBeforeStop = 0L
+    private var isRunning = false
+
+    init {
+        setOnChronometerTickListener {
+            if (hasReachedLimit()) {
+                setTextColor(ThemeUtils.getThemeAttrColor(context, R.attr.maxTimerColor))
+                stop()
+            }
+        }
+    }
+
+    override fun start() {
+        super.start()
+        isRunning = true
+    }
+
+    override fun stop() {
+        elapsedMillisBeforeStop = SystemClock.elapsedRealtime() - base
+        super.stop()
+        isRunning = false
+    }
+
+    fun resume() {
+        base = SystemClock.elapsedRealtime() - elapsedMillisBeforeStop
+        start()
+    }
+
+    fun restart() {
+        elapsedMillisBeforeStop = 0
+        base = SystemClock.elapsedRealtime()
+        setTextColor(ThemeUtils.getThemeAttrColor(context, android.R.attr.textColor))
+        start()
+    }
+
+    private fun hasReachedLimit() = SystemClock.elapsedRealtime() - base >= limitInMs
+
+    override fun onSaveInstanceState(): Parcelable {
+        val elapsedMillis = if (isRunning) SystemClock.elapsedRealtime() - base else elapsedMillisBeforeStop
+        return SavedState(
+            state = super.onSaveInstanceState(),
+            elapsedMs = elapsedMillis,
+            isRunning = isRunning,
+            limitInMs = limitInMs,
+        )
+    }
+
+    override fun onRestoreInstanceState(state: Parcelable?) {
+        if (state !is SavedState) {
+            super.onRestoreInstanceState(state)
+            return
+        }
+        super.onRestoreInstanceState(state.superState)
+
+        elapsedMillisBeforeStop = state.elapsedMs
+        isRunning = state.isRunning
+        limitInMs = state.limitInMs
+
+        base = SystemClock.elapsedRealtime() - elapsedMillisBeforeStop
+        if (isRunning && !hasReachedLimit()) {
+            super.start()
+        }
+    }
+
+    @Parcelize
+    private data class SavedState(
+        val state: Parcelable?,
+        val elapsedMs: Long,
+        val isRunning: Boolean,
+        val limitInMs: Int,
+    ) : BaseSavedState(state)
+}

AnkiDroid/src/main/java/com/ichi2/anki/ui/windows/reviewer/AnswerTimerStatus.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2025 Brayan Oliveira <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.ichi2.anki.ui.windows.reviewer
+
+import kotlin.random.Random
+
+sealed interface AnswerTimerStatus {
+    data class Running(
+        val limitInMs: Int,
+    ) : AnswerTimerStatus {
+        // allows emitting the same value in MutableStateFlow
+        override fun equals(other: Any?): Boolean = false
+
+        override fun hashCode(): Int = Random.nextInt()
+    }
+
+    data object Stopped : AnswerTimerStatus
+}

AnkiDroid/src/main/java/com/ichi2/anki/ui/windows/reviewer/ReviewerFragment.kt

@@ -119,6 +119,8 @@ class ReviewerFragment :
     override val webView: WebView
         get() = requireView().findViewById(R.id.webview)
 
+    private val timer: AnswerTimer? get() = view?.findViewById(R.id.timer)
+
     override val baseSnackbarBuilder: SnackbarBuilder = {
         val fragmentView = [email protected]
         val typeAnswerContainer = fragmentView?.findViewById<View>(R.id.type_answer_container)
@@ -144,10 +146,20 @@ class ReviewerFragment :
             nightMode = Themes.currentTheme.isNightMode,
         )
 
+    override fun onStart() {
+        super.onStart()
+        if (!requireActivity().isChangingConfigurations) {
+            if (viewModel.answerTimerStatusFlow.value is AnswerTimerStatus.Running) {
+                timer?.resume()
+            }
+        }
+    }
+
     override fun onStop() {
         super.onStop()
         if (!requireActivity().isChangingConfigurations) {
             viewModel.stopAutoAdvance()
+            timer?.stop()
         }
     }
 
@@ -177,6 +189,7 @@ class ReviewerFragment :
         setupCounts(view)
         setupMenu(view)
         setupToolbarPosition(view)
+        setupAnswerTimer(view)
 
         viewModel.actionFeedbackFlow
             .flowWithLifecycle(lifecycle)
@@ -560,6 +573,27 @@ class ReviewerFragment :
         }
     }
 
+    private fun setupAnswerTimer(view: View) {
+        val timer = view.findViewById<AnswerTimer>(R.id.timer)
+        timer.isVisible = viewModel.answerTimerStatusFlow.value != null // necessary to handle configuration changes
+        viewModel.answerTimerStatusFlow.collectIn(lifecycleScope) { status ->
+            when (status) {
+                is AnswerTimerStatus.Running -> {
+                    timer.isVisible = true
+                    timer.limitInMs = status.limitInMs
+                    timer.restart()
+                }
+                AnswerTimerStatus.Stopped -> {
+                    timer.isVisible = true
+                    timer.stop()
+                }
+                null -> {
+                    timer.isVisible = false
+                }
+            }
+        }
+    }
+
     override fun onSelectedTags(
         selectedTags: List<String>,
         indeterminateTags: List<String>,

AnkiDroid/src/main/java/com/ichi2/anki/ui/windows/reviewer/ReviewerViewModel.kt

@@ -59,6 +59,7 @@ import com.ichi2.anki.ui.windows.reviewer.autoadvance.AutoAdvance
 import com.ichi2.anki.utils.Destination
 import com.ichi2.anki.utils.ext.flag
 import com.ichi2.anki.utils.ext.setUserFlagForCards
+import com.ichi2.libanki.Card
 import com.ichi2.libanki.CardId
 import com.ichi2.libanki.ChangeManager
 import com.ichi2.libanki.NoteId
@@ -103,6 +104,7 @@ class ReviewerViewModel(
     val destinationFlow = MutableSharedFlow<Destination>()
     val editNoteTagsFlow = MutableSharedFlow<NoteId>()
     val setDueDateFlow = MutableSharedFlow<CardId>()
+    val answerTimerStatusFlow = MutableStateFlow<AnswerTimerStatus?>(null)
 
     override val server: AnkiServer = AnkiServer(this, serverPort).also { it.start() }
     private val stateMutationKey = TimeManager.time.intTimeMS().toString()
@@ -186,6 +188,13 @@ class ReviewerViewModel(
             if (!autoAdvance.shouldWaitForAudio()) {
                 autoAdvance.onShowAnswer()
             } // else wait for onMediaGroupCompleted
+
+            if (answerTimerStatusFlow.value == null) return@launchCatchingIO
+            val did = currentCard.await().currentDeckId()
+            val stopTimerOnAnswer = withCol { decks.configDictForDeckId(did) }.stopTimerOnAnswer
+            if (stopTimerOnAnswer) {
+                answerTimerStatusFlow.emit(AnswerTimerStatus.Stopped)
+            }
         }
     }
 
@@ -483,6 +492,7 @@ class ReviewerViewModel(
 
         val card = state.topCard
         currentCard = CompletableDeferred(card)
+        setupAnswerTimer(card)
         autoAdvance.onCardChange(card)
         showQuestion()
         loadAndPlayMedia(CardSide.QUESTION)
@@ -559,6 +569,16 @@ class ReviewerViewModel(
         setDueDateFlow.emit(cardId)
     }
 
+    private suspend fun setupAnswerTimer(card: Card) {
+        val shouldShowTimer = withCol { card.shouldShowTimer(this@withCol) }
+        if (!shouldShowTimer) {
+            answerTimerStatusFlow.emit(null)
+            return
+        }
+        val limitInMillis = withCol { card.timeLimit(this@withCol) }
+        answerTimerStatusFlow.emit(AnswerTimerStatus.Running(limitInMillis))
+    }
+
     private fun executeAction(action: ViewerAction) {
         Timber.v("ReviewerViewModel::executeAction %s", action.name)
         launchCatchingIO {

AnkiDroid/src/main/res/layout-sw600dp/reviewer2.xml

@@ -106,10 +106,6 @@
                 android:textColor="?attr/newCountColor"
                 android:paddingEnd="4dp"
                 android:textSize="16sp"
-                app:layout_constraintTop_toTopOf="@id/back_button"
-                app:layout_constraintBottom_toBottomOf="@id/back_button"
-                app:layout_constraintStart_toEndOf="@id/back_button"
-                app:layout_constraintEnd_toStartOf="@id/lrn_count"
                 tools:text="127"
                 />
 
@@ -120,10 +116,6 @@
                 android:textColor="?attr/learnCountColor"
                 android:paddingHorizontal="4dp"
                 android:textSize="16sp"
-                app:layout_constraintTop_toTopOf="@id/back_button"
-                app:layout_constraintBottom_toBottomOf="@id/back_button"
-                app:layout_constraintStart_toEndOf="@id/new_count"
-                app:layout_constraintEnd_toStartOf="@id/rev_count"
                 tools:text="381"
                 />
 
@@ -134,12 +126,32 @@
                 android:textColor="?attr/reviewCountColor"
                 android:paddingStart="4dp"
                 android:textSize="16sp"
-                app:layout_constraintTop_toTopOf="@id/back_button"
-                app:layout_constraintBottom_toBottomOf="@id/back_button"
-                app:layout_constraintStart_toEndOf="@id/lrn_count"
                 tools:text="954"
                 />
 
+            <androidx.constraintlayout.helper.widget.Flow
+                android:id="@+id/counts_flow"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                app:constraint_referenced_ids="new_count,lrn_count,rev_count"
+                app:layout_constraintTop_toTopOf="parent"
+                app:layout_constraintStart_toEndOf="@id/back_button"
+                app:layout_constraintBottom_toTopOf="@id/timer"
+                />
+
+
+            <com.ichi2.anki.ui.windows.reviewer.AnswerTimer
+                android:id="@+id/timer"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                app:layout_constraintTop_toBottomOf="@id/counts_flow"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintEnd_toEndOf="@id/counts_flow"
+                app:layout_constraintStart_toStartOf="@id/counts_flow"
+                android:visibility="gone"
+                tools:visibility="visible"
+                />
+
             <FrameLayout
                 android:id="@+id/answer_area"
                 android:layout_width="0dp"