Handling back gesture in BackGestureTutorialScreen

The only thing that's reacting to the gesture now is title text changing to "Done"

- registering MotionEvents handler to pass to ViewModel
- GestureTutorialViewModel filters events coming from touchpad
- BackGestureMonitor receives touchpad events and contains logic for recognizing the gesture

Also introducing FakeMotionEvent methods that will be helpful for testing MotionEvents

Bug: 346579074
Flag: com.android.systemui.shared.new_touchpad_gestures_tutorial
Test: manually, see video
Test: BackGestureMonitorTest
Test: GestureTutorialViewModelTest
Change-Id: I516c6d661e5d332fcccc78c21580095ddf90f4a7

10 files changed, 555 insertions, 63 deletions

diff --git a/packages/SystemUI/res/values/strings.xml b/packages/SystemUI/res/values/strings.xml
index 82dafc3ed1df..5d568b78bcdc 100644
--- a/packages/SystemUI/res/values/strings.xml
+++ b/packages/SystemUI/res/values/strings.xml
@@ -3577,6 +3577,8 @@
     <string name="touchpad_tutorial_action_key_button">Action key</string>
     <!-- Label for button finishing touchpad tutorial [CHAR LIMIT=NONE] -->
     <string name="touchpad_tutorial_done_button">Done</string>
+    <!-- Screen title after gesture was done successfully [CHAR LIMIT=NONE] -->
+    <string name="touchpad_tutorial_gesture_done">Great job!</string>
     <!-- Touchpad back gesture action name in tutorial [CHAR LIMIT=NONE] -->
     <string name="touchpad_back_gesture_action_title">Go back</string>
     <!-- Touchpad back gesture guidance in gestures tutorial [CHAR LIMIT=NONE] -->
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/GestureViewModelFactory.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/GestureViewModelFactory.kt
deleted file mode 100644
index 504bd5fbcb42..000000000000
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/GestureViewModelFactory.kt
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.systemui.touchpad.tutorial.ui
-
-import androidx.lifecycle.ViewModel
-import androidx.lifecycle.ViewModelProvider
-
-sealed class GestureTutorialViewModel : ViewModel()
-
-class BackGestureTutorialViewModel : GestureTutorialViewModel()
-
-class HomeGestureTutorialViewModel : GestureTutorialViewModel()
-
-class GestureViewModelFactory : ViewModelProvider.Factory {
-
-    @Suppress("UNCHECKED_CAST")
-    override fun <T : ViewModel> create(modelClass: Class<T>): T {
-        return when (modelClass) {
-            BackGestureTutorialViewModel::class.java -> BackGestureTutorialViewModel()
-            HomeGestureTutorialViewModel::class.java -> HomeGestureTutorialViewModel()
-            else -> error("Unknown ViewModel class: ${modelClass.name}")
-        }
-            as T
-    }
-}
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt
new file mode 100644
index 000000000000..1fa7a0c44171
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.MotionEvent
+import kotlin.math.abs
+
+/**
+ * Monitor for touchpad gestures that calls [gestureDoneCallback] when gesture was successfully
+ * done. All tracked motion events should be passed to [processTouchpadEvent]
+ */
+interface TouchpadGestureMonitor {
+
+    val gestureDistanceThresholdPx: Int
+    val gestureDoneCallback: () -> Unit
+
+    fun processTouchpadEvent(event: MotionEvent)
+}
+
+class BackGestureMonitor(
+    override val gestureDistanceThresholdPx: Int,
+    override val gestureDoneCallback: () -> Unit
+) : TouchpadGestureMonitor {
+
+    private var xStart = 0f
+
+    override fun processTouchpadEvent(event: MotionEvent) {
+        val action = event.actionMasked
+        when (action) {
+            MotionEvent.ACTION_DOWN -> {
+                if (isThreeFingerTouchpadSwipe(event)) {
+                    xStart = event.x
+                }
+            }
+            MotionEvent.ACTION_UP -> {
+                if (isThreeFingerTouchpadSwipe(event)) {
+                    val distance = abs(event.x - xStart)
+                    if (distance >= gestureDistanceThresholdPx) {
+                        gestureDoneCallback()
+                    }
+                }
+            }
+        }
+    }
+
+    private fun isThreeFingerTouchpadSwipe(event: MotionEvent): Boolean {
+        return event.classification == MotionEvent.CLASSIFICATION_MULTI_FINGER_SWIPE &&
+            event.getAxisValue(MotionEvent.AXIS_GESTURE_SWIPE_FINGER_COUNT) == 3f
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGesture.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGesture.kt
new file mode 100644
index 000000000000..4ae9c7b2426c
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGesture.kt
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+enum class TouchpadGesture {
+    BACK,
+    HOME;
+
+    fun toMonitor(
+        swipeDistanceThresholdPx: Int,
+        gestureDoneCallback: () -> Unit
+    ): TouchpadGestureMonitor {
+        return when (this) {
+            BACK -> BackGestureMonitor(swipeDistanceThresholdPx, gestureDoneCallback)
+            else -> throw IllegalArgumentException("Not implemented yet")
+        }
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandler.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandler.kt
new file mode 100644
index 000000000000..dc8471c3248a
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandler.kt
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.InputDevice
+import android.view.MotionEvent
+
+/**
+ * Allows listening to touchpadGesture and calling onDone when gesture was triggered. Can have all
+ * motion events passed to [onMotionEvent] and will filter touchpad events accordingly
+ */
+class TouchpadGestureHandler(
+    touchpadGesture: TouchpadGesture,
+    swipeDistanceThresholdPx: Int,
+    onDone: () -> Unit
+) {
+
+    private val gestureRecognition =
+        touchpadGesture.toMonitor(swipeDistanceThresholdPx, gestureDoneCallback = onDone)
+
+    fun onMotionEvent(event: MotionEvent): Boolean {
+        // events from touchpad have SOURCE_MOUSE and not SOURCE_TOUCHPAD because of legacy reasons
+        val isFromTouchpad =
+            event.isFromSource(InputDevice.SOURCE_MOUSE) &&
+                event.getToolType(0) == MotionEvent.TOOL_TYPE_FINGER
+        val buttonClick =
+            event.actionMasked == MotionEvent.ACTION_DOWN &&
+                event.isButtonPressed(MotionEvent.BUTTON_PRIMARY)
+        return if (isFromTouchpad && !buttonClick) {
+            gestureRecognition.processTouchpadEvent(event)
+            true
+        } else {
+            false
+        }
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/BackGestureTutorialScreen.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/BackGestureTutorialScreen.kt
index 2460761c8592..04a47985dc29 100644
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/BackGestureTutorialScreen.kt
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/BackGestureTutorialScreen.kt
@@ -17,9 +17,11 @@
 package com.android.systemui.touchpad.tutorial.ui.view
 
 import androidx.activity.compose.BackHandler
+import androidx.annotation.StringRes
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
@@ -31,29 +33,67 @@ import androidx.compose.foundation.layout.width
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.ExperimentalComposeUiApi
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.input.pointer.pointerInteropFilter
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import com.android.systemui.res.R
+import com.android.systemui.touchpad.tutorial.ui.gesture.TouchpadGesture.BACK
+import com.android.systemui.touchpad.tutorial.ui.gesture.TouchpadGestureHandler
 
+@OptIn(ExperimentalComposeUiApi::class)
 @Composable
 fun BackGestureTutorialScreen(
     onDoneButtonClicked: () -> Unit,
     onBack: () -> Unit,
-    modifier: Modifier = Modifier,
 ) {
-    BackHandler { onBack() }
+    BackHandler(onBack = onBack)
+    var gestureDone by remember { mutableStateOf(false) }
+    val swipeDistanceThresholdPx =
+        with(LocalContext.current) {
+            resources.getDimensionPixelSize(
+                com.android.internal.R.dimen.system_gestures_distance_threshold
+            )
+        }
+    val gestureHandler =
+        remember(swipeDistanceThresholdPx) {
+            TouchpadGestureHandler(BACK, swipeDistanceThresholdPx, onDone = { gestureDone = true })
+        }
+    Box(
+        modifier =
+            Modifier.fillMaxSize()
+                // we need to use pointerInteropFilter because some info about touchpad gestures is
+                // only available in MotionEvent
+                .pointerInteropFilter(onTouchEvent = gestureHandler::onMotionEvent)
+    ) {
+        GestureTutorialContent(gestureDone, onDoneButtonClicked)
+    }
+}
+
+@Composable
+private fun GestureTutorialContent(gestureDone: Boolean, onDoneButtonClicked: () -> Unit) {
     Column(
         verticalArrangement = Arrangement.Center,
         modifier =
-            modifier
+            Modifier.fillMaxSize()
                 .background(color = MaterialTheme.colorScheme.surfaceContainer)
                 .padding(start = 48.dp, top = 124.dp, end = 48.dp, bottom = 48.dp)
-                .fillMaxSize()
     ) {
         Row(modifier = Modifier.fillMaxWidth().weight(1f)) {
-            TutorialDescription(modifier = Modifier.weight(1f))
+            TutorialDescription(
+                titleTextId =
+                    if (gestureDone) R.string.touchpad_tutorial_gesture_done
+                    else R.string.touchpad_back_gesture_action_title,
+                bodyTextId = R.string.touchpad_back_gesture_guidance,
+                modifier = Modifier.weight(1f)
+            )
             Spacer(modifier = Modifier.width(76.dp))
             TutorialAnimation(modifier = Modifier.weight(1f).padding(top = 24.dp))
         }
@@ -62,17 +102,15 @@ fun BackGestureTutorialScreen(
 }
 
 @Composable
-fun TutorialDescription(modifier: Modifier = Modifier) {
+fun TutorialDescription(
+    @StringRes titleTextId: Int,
+    @StringRes bodyTextId: Int,
+    modifier: Modifier = Modifier
+) {
     Column(verticalArrangement = Arrangement.Top, modifier = modifier) {
-        Text(
-            text = stringResource(id = R.string.touchpad_back_gesture_action_title),
-            style = MaterialTheme.typography.displayLarge
-        )
+        Text(text = stringResource(id = titleTextId), style = MaterialTheme.typography.displayLarge)
         Spacer(modifier = Modifier.height(16.dp))
-        Text(
-            text = stringResource(id = R.string.touchpad_back_gesture_guidance),
-            style = MaterialTheme.typography.bodyLarge
-        )
+        Text(text = stringResource(id = bodyTextId), style = MaterialTheme.typography.bodyLarge)
     }
 }
 
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/TouchpadTutorialActivity.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/TouchpadTutorialActivity.kt
index 0c5c1874db8a..93c26583e11e 100644
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/TouchpadTutorialActivity.kt
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/view/TouchpadTutorialActivity.kt
@@ -17,6 +17,7 @@
 package com.android.systemui.touchpad.tutorial.ui.view
 
 import android.os.Bundle
+import android.view.WindowManager
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
@@ -25,10 +26,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.lifecycle.Lifecycle.State.STARTED
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
-import androidx.lifecycle.viewmodel.compose.viewModel
 import com.android.compose.theme.PlatformTheme
-import com.android.systemui.touchpad.tutorial.ui.GestureViewModelFactory
-import com.android.systemui.touchpad.tutorial.ui.HomeGestureTutorialViewModel
 import com.android.systemui.touchpad.tutorial.ui.Screen.BACK_GESTURE
 import com.android.systemui.touchpad.tutorial.ui.Screen.HOME_GESTURE
 import com.android.systemui.touchpad.tutorial.ui.Screen.TUTORIAL_SELECTION
@@ -47,6 +45,8 @@ constructor(
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
         setContent { PlatformTheme { TouchpadTutorialScreen(vm) { finish() } } }
+        // required to handle 3+ fingers on touchpad
+        window.addPrivateFlags(WindowManager.LayoutParams.PRIVATE_FLAG_TRUSTED_OVERLAY)
     }
 
     override fun onResume() {
@@ -74,13 +74,8 @@ fun TouchpadTutorialScreen(vm: TouchpadTutorialViewModel, closeTutorial: () -> U
         BACK_GESTURE ->
             BackGestureTutorialScreen(
                 onDoneButtonClicked = { vm.goTo(TUTORIAL_SELECTION) },
-                onBack = { vm.goTo(TUTORIAL_SELECTION) }
+                onBack = { vm.goTo(TUTORIAL_SELECTION) },
             )
-        HOME_GESTURE -> HomeGestureTutorialScreen()
+        HOME_GESTURE -> {}
     }
 }
-
-@Composable
-fun HomeGestureTutorialScreen() {
-    val vm = viewModel<HomeGestureTutorialViewModel>(factory = GestureViewModelFactory())
-}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitorTest.kt b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitorTest.kt
new file mode 100644
index 000000000000..cf0db7b51676
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitorTest.kt
@@ -0,0 +1,160 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.MotionEvent
+import android.view.MotionEvent.ACTION_DOWN
+import android.view.MotionEvent.ACTION_MOVE
+import android.view.MotionEvent.ACTION_POINTER_DOWN
+import android.view.MotionEvent.ACTION_POINTER_UP
+import android.view.MotionEvent.ACTION_UP
+import android.view.MotionEvent.AXIS_GESTURE_SWIPE_FINGER_COUNT
+import android.view.MotionEvent.CLASSIFICATION_MULTI_FINGER_SWIPE
+import android.view.MotionEvent.CLASSIFICATION_TWO_FINGER_SWIPE
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@SmallTest
+@RunWith(AndroidJUnit4::class)
+class BackGestureMonitorTest : SysuiTestCase() {
+
+    private var gestureDoneWasCalled = false
+    private val gestureDoneCallback = { gestureDoneWasCalled = true }
+    private val gestureMonitor = BackGestureMonitor(SWIPE_DISTANCE.toInt(), gestureDoneCallback)
+
+    companion object {
+        const val SWIPE_DISTANCE = 100f
+    }
+
+    @Test
+    fun triggersGestureDoneForThreeFingerGestureRight() {
+        val events =
+            listOf(
+                threeFingerEvent(ACTION_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_MOVE, x = SWIPE_DISTANCE / 2, y = 0f),
+                threeFingerEvent(ACTION_POINTER_UP, x = SWIPE_DISTANCE, y = 0f),
+                threeFingerEvent(ACTION_POINTER_UP, x = SWIPE_DISTANCE, y = 0f),
+                threeFingerEvent(ACTION_UP, x = SWIPE_DISTANCE, y = 0f),
+            )
+
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+
+        assertThat(gestureDoneWasCalled).isTrue()
+    }
+
+    @Test
+    fun triggersGestureDoneForThreeFingerGestureLeft() {
+        val events =
+            listOf(
+                threeFingerEvent(ACTION_DOWN, x = SWIPE_DISTANCE, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = SWIPE_DISTANCE, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = SWIPE_DISTANCE, y = 0f),
+                threeFingerEvent(ACTION_MOVE, x = SWIPE_DISTANCE / 2, y = 0f),
+                threeFingerEvent(ACTION_POINTER_UP, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_POINTER_UP, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_UP, x = 0f, y = 0f),
+            )
+
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+
+        assertThat(gestureDoneWasCalled).isTrue()
+    }
+
+    private fun threeFingerEvent(action: Int, x: Float, y: Float): MotionEvent {
+        return motionEvent(
+            action = action,
+            x = x,
+            y = y,
+            classification = CLASSIFICATION_MULTI_FINGER_SWIPE,
+            axisValues = mapOf(AXIS_GESTURE_SWIPE_FINGER_COUNT to 3f)
+        )
+    }
+
+    @Test
+    fun doesntTriggerGestureDone_onThreeFingersSwipeUp() {
+        val events =
+            listOf(
+                threeFingerEvent(ACTION_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                threeFingerEvent(ACTION_MOVE, x = 0f, y = SWIPE_DISTANCE / 2),
+                threeFingerEvent(ACTION_POINTER_UP, x = 0f, y = SWIPE_DISTANCE),
+                threeFingerEvent(ACTION_POINTER_UP, x = 0f, y = SWIPE_DISTANCE),
+                threeFingerEvent(ACTION_UP, x = 0f, y = SWIPE_DISTANCE),
+            )
+
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+
+        assertThat(gestureDoneWasCalled).isFalse()
+    }
+
+    @Test
+    fun doesntTriggerGestureDone_onTwoFingersSwipe() {
+        fun twoFingerEvent(action: Int, x: Float, y: Float) =
+            motionEvent(
+                action = action,
+                x = x,
+                y = y,
+                classification = CLASSIFICATION_TWO_FINGER_SWIPE,
+                axisValues = mapOf(AXIS_GESTURE_SWIPE_FINGER_COUNT to 2f)
+            )
+        val events =
+            listOf(
+                twoFingerEvent(ACTION_DOWN, x = 0f, y = 0f),
+                twoFingerEvent(ACTION_MOVE, x = SWIPE_DISTANCE / 2, y = 0f),
+                twoFingerEvent(ACTION_UP, x = SWIPE_DISTANCE, y = 0f),
+            )
+
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+
+        assertThat(gestureDoneWasCalled).isFalse()
+    }
+
+    @Test
+    fun doesntTriggerGestureDone_onFourFingersSwipe() {
+        fun fourFingerEvent(action: Int, x: Float, y: Float) =
+            motionEvent(
+                action = action,
+                x = x,
+                y = y,
+                classification = CLASSIFICATION_MULTI_FINGER_SWIPE,
+                axisValues = mapOf(AXIS_GESTURE_SWIPE_FINGER_COUNT to 4f)
+            )
+        val events =
+            listOf(
+                fourFingerEvent(ACTION_DOWN, x = 0f, y = 0f),
+                fourFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                fourFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                fourFingerEvent(ACTION_POINTER_DOWN, x = 0f, y = 0f),
+                fourFingerEvent(ACTION_MOVE, x = SWIPE_DISTANCE / 2, y = 0f),
+                fourFingerEvent(ACTION_POINTER_UP, x = SWIPE_DISTANCE, y = 0f),
+                fourFingerEvent(ACTION_POINTER_UP, x = SWIPE_DISTANCE, y = 0f),
+                fourFingerEvent(ACTION_POINTER_UP, x = SWIPE_DISTANCE, y = 0f),
+                fourFingerEvent(ACTION_UP, x = SWIPE_DISTANCE, y = 0f),
+            )
+
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+
+        assertThat(gestureDoneWasCalled).isFalse()
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/FakeMotionEvent.kt b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/FakeMotionEvent.kt
new file mode 100644
index 000000000000..e632e3474b96
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/FakeMotionEvent.kt
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.InputDevice.SOURCE_CLASS_POINTER
+import android.view.InputDevice.SOURCE_MOUSE
+import android.view.MotionEvent
+import android.view.MotionEvent.CLASSIFICATION_NONE
+import android.view.MotionEvent.TOOL_TYPE_FINGER
+import org.mockito.kotlin.doReturn
+import org.mockito.kotlin.spy
+
+fun motionEvent(
+    action: Int,
+    x: Float,
+    y: Float,
+    source: Int = 0,
+    toolType: Int = TOOL_TYPE_FINGER,
+    pointerCount: Int = 1,
+    axisValues: Map<Int, Float> = emptyMap(),
+    classification: Int = CLASSIFICATION_NONE,
+): MotionEvent {
+    val event =
+        MotionEvent.obtain(/* downTime= */ 0, /* eventTime= */ 0, action, x, y, /* metaState= */ 0)
+    event.source = source
+    return spy<MotionEvent>(event) {
+        on { getToolType(0) } doReturn toolType
+        on { getPointerCount() } doReturn pointerCount
+        axisValues.forEach { (key, value) -> on { getAxisValue(key) } doReturn value }
+        on { getClassification() } doReturn classification
+    }
+}
+
+fun touchpadEvent(
+    action: Int,
+    x: Float,
+    y: Float,
+    pointerCount: Int = 1,
+    classification: Int = CLASSIFICATION_NONE,
+    axisValues: Map<Int, Float> = emptyMap()
+): MotionEvent {
+    return motionEvent(
+        action = action,
+        x = x,
+        y = y,
+        source = SOURCE_MOUSE or SOURCE_CLASS_POINTER,
+        toolType = TOOL_TYPE_FINGER,
+        pointerCount = pointerCount,
+        classification = classification,
+        axisValues = axisValues
+    )
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandlerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandlerTest.kt
new file mode 100644
index 000000000000..769f264f0870
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/TouchpadGestureHandlerTest.kt
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.InputDevice.SOURCE_MOUSE
+import android.view.InputDevice.SOURCE_TOUCHSCREEN
+import android.view.MotionEvent
+import android.view.MotionEvent.ACTION_DOWN
+import android.view.MotionEvent.ACTION_HOVER_ENTER
+import android.view.MotionEvent.ACTION_MOVE
+import android.view.MotionEvent.ACTION_POINTER_DOWN
+import android.view.MotionEvent.ACTION_POINTER_UP
+import android.view.MotionEvent.ACTION_UP
+import android.view.MotionEvent.AXIS_GESTURE_SWIPE_FINGER_COUNT
+import android.view.MotionEvent.CLASSIFICATION_MULTI_FINGER_SWIPE
+import android.view.MotionEvent.TOOL_TYPE_FINGER
+import android.view.MotionEvent.TOOL_TYPE_MOUSE
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.touchpad.tutorial.ui.gesture.TouchpadGesture.BACK
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@SmallTest
+@RunWith(AndroidJUnit4::class)
+class TouchpadGestureHandlerTest : SysuiTestCase() {
+
+    private var gestureDone = false
+    private val handler = TouchpadGestureHandler(BACK, SWIPE_DISTANCE) { gestureDone = true }
+
+    companion object {
+        const val SWIPE_DISTANCE = 100
+    }
+
+    @Test
+    fun handlesEventsFromTouchpad() {
+        val event = downEvent(source = SOURCE_MOUSE, toolType = TOOL_TYPE_FINGER)
+        val eventHandled = handler.onMotionEvent(event)
+        assertThat(eventHandled).isTrue()
+    }
+
+    @Test
+    fun ignoresEventsFromMouse() {
+        val event = downEvent(source = SOURCE_MOUSE, toolType = TOOL_TYPE_MOUSE)
+        val eventHandled = handler.onMotionEvent(event)
+        assertThat(eventHandled).isFalse()
+    }
+
+    @Test
+    fun ignoresEventsFromTouch() {
+        val event = downEvent(source = SOURCE_TOUCHSCREEN, toolType = TOOL_TYPE_FINGER)
+        val eventHandled = handler.onMotionEvent(event)
+        assertThat(eventHandled).isFalse()
+    }
+
+    @Test
+    fun ignoresButtonClicksFromTouchpad() {
+        val event = downEvent(source = SOURCE_MOUSE, toolType = TOOL_TYPE_FINGER)
+        event.buttonState = MotionEvent.BUTTON_PRIMARY
+        val eventHandled = handler.onMotionEvent(event)
+        assertThat(eventHandled).isFalse()
+    }
+
+    private fun downEvent(source: Int, toolType: Int) =
+        motionEvent(action = ACTION_DOWN, x = 0f, y = 0f, source = source, toolType = toolType)
+
+    @Test
+    fun triggersGestureDoneForThreeFingerGesture() {
+        backGestureEvents().forEach { handler.onMotionEvent(it) }
+
+        assertThat(gestureDone).isTrue()
+    }
+
+    private fun backGestureEvents(): List<MotionEvent> {
+        // list of motion events read from device while doing back gesture
+        val y = 100f
+        return listOf(
+            touchpadEvent(ACTION_HOVER_ENTER, x = 759f, y = y, pointerCount = 1),
+            threeFingerTouchpadEvent(ACTION_DOWN, x = 759f, y = y, pointerCount = 1),
+            threeFingerTouchpadEvent(ACTION_POINTER_DOWN, x = 759f, y = y, pointerCount = 2),
+            threeFingerTouchpadEvent(ACTION_POINTER_DOWN, x = 759f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_MOVE, x = 767f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_MOVE, x = 785f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_MOVE, x = 814f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_MOVE, x = 848f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_MOVE, x = 943f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_POINTER_UP, x = 943f, y = y, pointerCount = 3),
+            threeFingerTouchpadEvent(ACTION_POINTER_UP, x = 943f, y = y, pointerCount = 2),
+            threeFingerTouchpadEvent(ACTION_UP, x = 943f, y = y, pointerCount = 1)
+        )
+    }
+
+    private fun threeFingerTouchpadEvent(
+        action: Int,
+        x: Float,
+        y: Float,
+        pointerCount: Int
+    ): MotionEvent {
+        return touchpadEvent(
+            action = action,
+            x = x,
+            y = y,
+            pointerCount = pointerCount,
+            classification = CLASSIFICATION_MULTI_FINGER_SWIPE,
+            axisValues = mapOf(AXIS_GESTURE_SWIPE_FINGER_COUNT to 3f)
+        )
+    }
+}