ConditionalCoreStartable Introduction.

/*

 * 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.util.condition;

import com.android.systemui.CoreStartable;

import com.android.systemui.shared.condition.Condition;

import com.android.systemui.shared.condition.Monitor;

import java.util.Set;

/**

 * {@link ConditionalCoreStartable} is a {@link com.android.systemui.CoreStartable} abstract

 * implementation where conditions must be met before routines are executed.

 */

public abstract class ConditionalCoreStartable implements CoreStartable {

    private final Monitor mMonitor;

    private final Set<Condition> mConditionSet;

    private Monitor.Subscription.Token mStartToken;

    private Monitor.Subscription.Token mBootCompletedToken;

    public ConditionalCoreStartable(Monitor monitor) {

        this(monitor, null);

    }

    public ConditionalCoreStartable(Monitor monitor, Set<Condition> conditionSet) {

        mMonitor = monitor;

        mConditionSet = conditionSet;

    }

    @Override

    public final void start() {

        if (mConditionSet == null || mConditionSet.isEmpty()) {

            onStart();

            return;

        }

        mStartToken = mMonitor.addSubscription(

                new Monitor.Subscription.Builder(allConditionsMet -> {

                    if (allConditionsMet) {

                        mMonitor.removeSubscription(mStartToken);

                        mStartToken = null;

                        onStart();

                    }

                }).addConditions(mConditionSet)

                        .build());

    }

    protected abstract void onStart();

    @Override

    public final void onBootCompleted() {

        if (mConditionSet == null || mConditionSet.isEmpty()) {

            bootCompleted();

            return;

        }

        mBootCompletedToken = mMonitor.addSubscription(

                new Monitor.Subscription.Builder(allConditionsMet -> {

                    if (allConditionsMet) {

                        mMonitor.removeSubscription(mBootCompletedToken);

                        mBootCompletedToken = null;

                        bootCompleted();

                    }

                }).addConditions(mConditionSet)

                        .build());

    }

    protected void bootCompleted() {

    }

}

/*

 * 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.util.condition;

import static com.google.common.truth.Truth.assertThat;

import static org.mockito.ArgumentMatchers.any;

import static org.mockito.Mockito.never;

import static org.mockito.Mockito.verify;

import static org.mockito.Mockito.when;

import android.testing.AndroidTestingRunner;

import androidx.test.filters.SmallTest;

import com.android.systemui.CoreStartable;

import com.android.systemui.SysuiTestCase;

import com.android.systemui.shared.condition.Condition;

import com.android.systemui.shared.condition.Monitor;

import org.junit.Before;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.mockito.ArgumentCaptor;

import org.mockito.Mock;

import org.mockito.MockitoAnnotations;

import java.util.Arrays;

import java.util.HashSet;

import java.util.Set;

@SmallTest

@RunWith(AndroidTestingRunner.class)

public class ConditionalCoreStartableTest extends SysuiTestCase {

    public static class FakeConditionalCoreStartable extends ConditionalCoreStartable {

        interface Callback {

            void onStart();

            void bootCompleted();

        }

        private final Callback mCallback;

        public FakeConditionalCoreStartable(Monitor monitor, Set<Condition> conditions,

                Callback callback) {

            super(monitor, conditions);

            mCallback = callback;

        }

        @Override

        protected void onStart() {

            mCallback.onStart();

        }

        @Override

        protected void bootCompleted() {

            mCallback.bootCompleted();

        }

    }

    final Set<Condition> mConditions = new HashSet<>();

    @Mock

    Condition mCondition;

    @Mock

    Monitor mMonitor;

    @Mock

    FakeConditionalCoreStartable.Callback mCallback;

    @Mock

    Monitor.Subscription.Token mSubscriptionToken;

    @Before

    public void setup() {

        MockitoAnnotations.initMocks(this);

        mConditions.clear();

    }

    /**

     * Verifies that {@link ConditionalCoreStartable#onStart()} is predicated on conditions being

     * met.

     */

    @Test

    public void testOnStartCallback() {

        final CoreStartable coreStartable =

                new FakeConditionalCoreStartable(mMonitor,

                        new HashSet<>(Arrays.asList(mCondition)),

                        mCallback);

        when(mMonitor.addSubscription(any())).thenReturn(mSubscriptionToken);

        coreStartable.start();

        final ArgumentCaptor<Monitor.Subscription> subscriptionCaptor = ArgumentCaptor.forClass(

                Monitor.Subscription.class);

        verify(mMonitor).addSubscription(subscriptionCaptor.capture());

        final Monitor.Subscription subscription = subscriptionCaptor.getValue();

        assertThat(subscription.getConditions()).containsExactly(mCondition);

        verify(mCallback, never()).onStart();

        subscription.getCallback().onConditionsChanged(true);

        verify(mCallback).onStart();

        verify(mMonitor).removeSubscription(mSubscriptionToken);

    }

    /**

     * Verifies that {@link ConditionalCoreStartable#bootCompleted()} ()} is predicated on

     * conditions being met.

     */

    @Test

    public void testBootCompleted() {

        final CoreStartable coreStartable =

                new FakeConditionalCoreStartable(mMonitor,

                        new HashSet<>(Arrays.asList(mCondition)),

                        mCallback);

        when(mMonitor.addSubscription(any())).thenReturn(mSubscriptionToken);

        coreStartable.onBootCompleted();

        final ArgumentCaptor<Monitor.Subscription> subscriptionCaptor = ArgumentCaptor.forClass(

                Monitor.Subscription.class);

        verify(mMonitor).addSubscription(subscriptionCaptor.capture());

        final Monitor.Subscription subscription = subscriptionCaptor.getValue();

        assertThat(subscription.getConditions()).containsExactly(mCondition);

        verify(mCallback, never()).bootCompleted();

        subscription.getCallback().onConditionsChanged(true);

        verify(mCallback).bootCompleted();

        verify(mMonitor).removeSubscription(mSubscriptionToken);

    }

}