Introduce ConnectedDisplayInteractor

This class provides the status of external connected devices though a
Flow.

Used in child cls to add a status bar icon when an external display is
connected.

Bug: 286186256
Test: ConnectedDisplayInteractorTest
Change-Id: Ib31a9bcbd2062488eed4b4933b814929704a4ff2

packages/SystemUI/src/com/android/systemui/dagger/SystemUIModule.java

@@ -47,6 +47,7 @@ import com.android.systemui.controls.dagger.ControlsModule;
 import com.android.systemui.dagger.qualifiers.Main;
 import com.android.systemui.dagger.qualifiers.SystemUser;
 import com.android.systemui.demomode.dagger.DemoModeModule;
+import com.android.systemui.display.DisplayModule;
 import com.android.systemui.doze.dagger.DozeComponent;
 import com.android.systemui.dreams.dagger.DreamModule;
 import com.android.systemui.dump.DumpManager;
@@ -163,6 +164,7 @@ import javax.inject.Named;
             ClipboardOverlayModule.class,
             ClockRegistryModule.class,
             CommonRepositoryModule.class,
+            DisplayModule.class,
             ConnectivityModule.class,
             CoroutinesModule.class,
             DreamModule.class,

packages/SystemUI/src/com/android/systemui/display/DisplayModule.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2023 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.display
+
+import com.android.systemui.display.data.repository.DisplayRepository
+import com.android.systemui.display.data.repository.DisplayRepositoryImpl
+import com.android.systemui.display.domain.interactor.ConnectedDisplayInteractor
+import com.android.systemui.display.domain.interactor.ConnectedDisplayInteractorImpl
+import dagger.Binds
+import dagger.Module
+
+/** Module binding display related classes. */
+@Module
+interface DisplayModule {
+    @Binds
+    fun bindConnectedDisplayInteractor(
+        provider: ConnectedDisplayInteractorImpl
+    ): ConnectedDisplayInteractor
+
+    @Binds fun bindsDisplayRepository(displayRepository: DisplayRepositoryImpl): DisplayRepository
+}

packages/SystemUI/src/com/android/systemui/display/domain/interactor/ConnectedDisplayInteractor.kt

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2023 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.display.domain.interactor
+
+import android.view.Display
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.display.data.repository.DisplayRepository
+import com.android.systemui.display.domain.interactor.ConnectedDisplayInteractor.State
+import javax.inject.Inject
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
+
+/** Provides information about an external connected display. */
+interface ConnectedDisplayInteractor {
+    /**
+     * Provides the current external display state.
+     *
+     * The state is:
+     * - [State.CONNECTED] when there is at least one display with [TYPE_EXTERNAL].
+     * - [State.CONNECTED_SECURE] when is at least one display with both [TYPE_EXTERNAL] AND
+     *   [Display.FLAG_SECURE] set
+     */
+    val connectedDisplayState: Flow<State>
+
+    /** Possible connected display state. */
+    enum class State {
+        DISCONNECTED,
+        CONNECTED,
+        CONNECTED_SECURE,
+    }
+}
+
+@SysUISingleton
+class ConnectedDisplayInteractorImpl
+@Inject
+constructor(
+    displayRepository: DisplayRepository,
+) : ConnectedDisplayInteractor {
+
+    override val connectedDisplayState: Flow<State> =
+        displayRepository.displays
+            .map { displays ->
+                val externalDisplays =
+                    displays.filter { display -> display.type == Display.TYPE_EXTERNAL }
+
+                val secureExternalDisplays =
+                    externalDisplays.filter { it.flags and Display.FLAG_SECURE != 0 }
+
+                if (externalDisplays.isEmpty()) {
+                    State.DISCONNECTED
+                } else if (!secureExternalDisplays.isEmpty()) {
+                    State.CONNECTED_SECURE
+                } else {
+                    State.CONNECTED
+                }
+            }
+            .distinctUntilChanged()
+}

packages/SystemUI/tests/src/com/android/systemui/display/domain/interactor/ConnectedDisplayInteractorTest.kt

@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2023 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.display.domain.interactor
+
+import android.testing.AndroidTestingRunner
+import android.testing.TestableLooper
+import android.view.Display
+import android.view.Display.TYPE_EXTERNAL
+import android.view.Display.TYPE_INTERNAL
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.coroutines.FlowValue
+import com.android.systemui.coroutines.collectLastValue
+import com.android.systemui.display.data.repository.DisplayRepository
+import com.android.systemui.display.domain.interactor.ConnectedDisplayInteractor.State
+import com.android.systemui.util.mockito.mock
+import com.android.systemui.util.mockito.whenever
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidTestingRunner::class)
+@TestableLooper.RunWithLooper
+@OptIn(ExperimentalCoroutinesApi::class)
+@SmallTest
+class ConnectedDisplayInteractorTest : SysuiTestCase() {
+
+    private val fakeDisplayRepository = FakeDisplayRepository()
+    private val connectedDisplayStateProvider: ConnectedDisplayInteractor =
+        ConnectedDisplayInteractorImpl(fakeDisplayRepository)
+    private val testScope = TestScope(UnconfinedTestDispatcher())
+
+    @Test
+    fun displayState_nullDisplays_disconnected() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(emptySet())
+
+            assertThat(value).isEqualTo(State.DISCONNECTED)
+        }
+
+    @Test
+    fun displayState_emptyDisplays_disconnected() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(emptySet())
+
+            assertThat(value).isEqualTo(State.DISCONNECTED)
+        }
+
+    @Test
+    fun displayState_internalDisplay_disconnected() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(setOf(display(type = TYPE_INTERNAL)))
+
+            assertThat(value).isEqualTo(State.DISCONNECTED)
+        }
+
+    @Test
+    fun displayState_externalDisplay_connected() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(setOf(display(type = TYPE_EXTERNAL)))
+
+            assertThat(value).isEqualTo(State.CONNECTED)
+        }
+
+    @Test
+    fun displayState_multipleExternalDisplays_connected() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(
+                setOf(display(type = TYPE_EXTERNAL), display(type = TYPE_EXTERNAL))
+            )
+
+            assertThat(value).isEqualTo(State.CONNECTED)
+        }
+
+    @Test
+    fun displayState_externalSecure_connectedSecure() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(
+                setOf(display(type = TYPE_EXTERNAL, flags = Display.FLAG_SECURE))
+            )
+
+            assertThat(value).isEqualTo(State.CONNECTED_SECURE)
+        }
+
+    @Test
+    fun displayState_multipleExternal_onlyOneSecure_connectedSecure() =
+        testScope.runTest {
+            val value by lastValue()
+
+            fakeDisplayRepository.emit(
+                setOf(
+                    display(type = TYPE_EXTERNAL, flags = Display.FLAG_SECURE),
+                    display(type = TYPE_EXTERNAL, flags = 0)
+                )
+            )
+
+            assertThat(value).isEqualTo(State.CONNECTED_SECURE)
+        }
+
+    private fun TestScope.lastValue(): FlowValue<State?> =
+        collectLastValue(connectedDisplayStateProvider.connectedDisplayState)
+
+    private fun display(type: Int, flags: Int = 0): Display {
+        return mock<Display>().also { mockDisplay ->
+            whenever(mockDisplay.type).thenReturn(type)
+            whenever(mockDisplay.flags).thenReturn(flags)
+        }
+    }
+
+    private class FakeDisplayRepository : DisplayRepository {
+        private val flow = MutableSharedFlow<Set<Display>>()
+        suspend fun emit(value: Set<Display>) = flow.emit(value)
+        override val displays: Flow<Set<Display>>
+            get() = flow
+    }
+}