/*
 * Copyright (C) 2015 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 android.telephony.cts;

import static android.net.NetworkCapabilities.NET_CAPABILITY_INTERNET;
import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED;
import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_METERED;
import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED;
import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import android.annotation.Nullable;
import android.content.pm.PackageManager;
import android.net.ConnectivityManager;
import android.net.ConnectivityManager.NetworkCallback;
import android.net.Network;
import android.net.NetworkCapabilities;
import android.net.NetworkRequest;
import android.support.test.InstrumentationRegistry;
import android.support.test.runner.AndroidJUnit4;
import android.telephony.SubscriptionInfo;
import android.telephony.SubscriptionManager;
import android.telephony.SubscriptionPlan;

import com.android.compatibility.common.util.SystemUtil;

import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import org.junit.runner.RunWith;

import java.time.Period;
import java.time.ZonedDateTime;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.function.Predicate;

@RunWith(AndroidJUnit4.class)
public class SubscriptionManagerTest {
    private SubscriptionManager mSm;

    private int mSubId;
    private String mPackageName;

    /**
     * Callback used in testRegisterNetworkCallback that allows caller to block on
     * {@code onAvailable}.
     */
    private static class TestNetworkCallback extends ConnectivityManager.NetworkCallback {
        private final CountDownLatch mAvailableLatch = new CountDownLatch(1);

        public void waitForAvailable() throws InterruptedException {
            assertTrue("Cellular network did not come up after 5 seconds",
                    mAvailableLatch.await(5, TimeUnit.SECONDS));
        }

        @Override
        public void onAvailable(Network network) {
            mAvailableLatch.countDown();
        }
    }

    @BeforeClass
    public static void setUpClass() throws Exception {
        InstrumentationRegistry.getInstrumentation().getUiAutomation()
                .executeShellCommand("svc wifi disable");

        final TestNetworkCallback callback = new TestNetworkCallback();
        final ConnectivityManager cm = InstrumentationRegistry.getContext()
                .getSystemService(ConnectivityManager.class);
        cm.registerNetworkCallback(new NetworkRequest.Builder()
                .addTransportType(TRANSPORT_CELLULAR)
                .addCapability(NET_CAPABILITY_INTERNET)
                .build(), callback);
        try {
            // Wait to get callback for availability of internet
            callback.waitForAvailable();
        } catch (InterruptedException e) {
            fail("NetworkCallback wait was interrupted.");
        } finally {
            cm.unregisterNetworkCallback(callback);
        }
    }

    @AfterClass
    public static void tearDownClass() throws Exception {
        InstrumentationRegistry.getInstrumentation().getUiAutomation()
                .executeShellCommand("svc wifi enable");
    }

    @Before
    public void setUp() throws Exception {
        mSm = InstrumentationRegistry.getContext().getSystemService(SubscriptionManager.class);
        mSubId = SubscriptionManager.getDefaultDataSubscriptionId();
        mPackageName = InstrumentationRegistry.getContext().getPackageName();
    }

    /**
     * Sanity check that both {@link PackageManager#FEATURE_TELEPHONY} and
     * {@link NetworkCapabilities#TRANSPORT_CELLULAR} network must both be
     * either defined or undefined; you can't cross the streams.
     */
    @Test
    public void testSanity() throws Exception {
        final boolean hasCellular = findCellularNetwork() != null;
        if (isSupported() && !hasCellular) {
            fail("Device claims to support " + PackageManager.FEATURE_TELEPHONY
                    + " but has no active cellular network, which is required for validation");
        } else if (!isSupported() && hasCellular) {
            fail("Device has active cellular network, but claims to not support "
                    + PackageManager.FEATURE_TELEPHONY);
        }

        if (isSupported()) {
            if (mSubId == SubscriptionManager.INVALID_SUBSCRIPTION_ID) {
                fail("Device must have a valid default data subId for validation");
            }
        }
    }

    @Test
    public void testGetActiveSubscriptionInfoCount() throws Exception {
        if (!isSupported()) return;

        assertTrue(mSm.getActiveSubscriptionInfoCount() <=
                mSm.getActiveSubscriptionInfoCountMax());
    }

    @Test
    public void testActiveSubscriptions() throws Exception {
        if (!isSupported()) return;

        List<SubscriptionInfo> subList = mSm.getActiveSubscriptionInfoList();
        // Assert when there is no sim card present or detected
        assertNotNull("Active subscriber required", subList);
        assertFalse("Active subscriber required", subList.isEmpty());
        for (int i = 0; i < subList.size(); i++) {
            assertTrue(subList.get(i).getSubscriptionId() >= 0);
            assertTrue(subList.get(i).getSimSlotIndex() >= 0);
        }
    }

    @Test
    public void testSubscriptionPlans() throws Exception {
        if (!isSupported()) return;

        // Make ourselves the owner
        setSubPlanOwner(mSubId, mPackageName);

        // Push empty list and we get empty back
        mSm.setSubscriptionPlans(mSubId, Arrays.asList());
        assertEquals(Arrays.asList(), mSm.getSubscriptionPlans(mSubId));

        // Push simple plan and get it back
        final SubscriptionPlan plan = buildValidSubscriptionPlan();
        mSm.setSubscriptionPlans(mSubId, Arrays.asList(plan));
        assertEquals(Arrays.asList(plan), mSm.getSubscriptionPlans(mSubId));

        // Now revoke our access
        setSubPlanOwner(mSubId, null);
        try {
            mSm.setSubscriptionPlans(mSubId, Arrays.asList());
            fail();
        } catch (SecurityException expected) {
        }
        try {
            mSm.getSubscriptionPlans(mSubId);
            fail();
        } catch (SecurityException expected) {
        }
    }

    @Test
    public void testSubscriptionPlansOverrideCongested() throws Exception {
        if (!isSupported()) return;

        final ConnectivityManager cm = InstrumentationRegistry.getContext()
                .getSystemService(ConnectivityManager.class);
        final Network net = findCellularNetwork();
        assertNotNull("Active cellular network required", net);

        // Make ourselves the owner
        setSubPlanOwner(mSubId, mPackageName);

        // Missing plans means no overrides
        mSm.setSubscriptionPlans(mSubId, Arrays.asList());
        try {
            mSm.setSubscriptionOverrideCongested(mSubId, true, 0);
            fail();
        } catch (SecurityException | IllegalStateException expected) {
        }

        // Defining plans means we get to override
        mSm.setSubscriptionPlans(mSubId, Arrays.asList(buildValidSubscriptionPlan()));

        // Cellular is uncongested by default
        assertTrue(cm.getNetworkCapabilities(net).hasCapability(NET_CAPABILITY_NOT_CONGESTED));

        // Override should make it go congested
        {
            final CountDownLatch latch = waitForNetworkCapabilities(net, caps -> {
                return !caps.hasCapability(NET_CAPABILITY_NOT_CONGESTED);
            });
            mSm.setSubscriptionOverrideCongested(mSubId, true, 0);
            assertTrue(latch.await(10, TimeUnit.SECONDS));
        }

        // Clearing override should make it go uncongested
        {
            final CountDownLatch latch = waitForNetworkCapabilities(net, caps -> {
                return caps.hasCapability(NET_CAPABILITY_NOT_CONGESTED);
            });
            mSm.setSubscriptionOverrideCongested(mSubId, false, 0);
            assertTrue(latch.await(10, TimeUnit.SECONDS));
        }

        // Now revoke our access
        setSubPlanOwner(mSubId, null);
        try {
            mSm.setSubscriptionOverrideCongested(mSubId, true, 0);
            fail();
        } catch (SecurityException | IllegalStateException expected) {
        }
    }

    @Test
    public void testSubscriptionPlansOverrideUnmetered() throws Exception {
        if (!isSupported()) return;

        final ConnectivityManager cm = InstrumentationRegistry.getContext()
                .getSystemService(ConnectivityManager.class);
        final Network net = findCellularNetwork();
        assertNotNull("Active cellular network required", net);

        // Make ourselves the owner and define some plans
        setSubPlanOwner(mSubId, mPackageName);
        mSm.setSubscriptionPlans(mSubId, Arrays.asList(buildValidSubscriptionPlan()));

        // Cellular is metered by default
        assertFalse(cm.getNetworkCapabilities(net).hasCapability(NET_CAPABILITY_NOT_METERED));

        // Override should make it go unmetered
        {
            final CountDownLatch latch = waitForNetworkCapabilities(net, caps -> {
                return caps.hasCapability(NET_CAPABILITY_NOT_METERED);
            });
            mSm.setSubscriptionOverrideUnmetered(mSubId, true, 0);
            assertTrue(latch.await(10, TimeUnit.SECONDS));
        }

        // Clearing override should make it go metered
        {
            final CountDownLatch latch = waitForNetworkCapabilities(net, caps -> {
                return !caps.hasCapability(NET_CAPABILITY_NOT_METERED);
            });
            mSm.setSubscriptionOverrideUnmetered(mSubId, false, 0);
            assertTrue(latch.await(10, TimeUnit.SECONDS));
        }
    }

    @Test
    public void testSubscriptionPlansInvalid() throws Exception {
        if (!isSupported()) return;

        // Make ourselves the owner
        setSubPlanOwner(mSubId, mPackageName);

        // Empty plans can't override
        assertOverrideFails();

        // Nonrecurring plan in the past can't override
        assertOverrideFails(SubscriptionPlan.Builder
                .createNonrecurring(ZonedDateTime.now().minusDays(14),
                        ZonedDateTime.now().minusDays(7))
                .setTitle("CTS")
                .setDataLimit(1_000_000_000, SubscriptionPlan.LIMIT_BEHAVIOR_DISABLED)
                .build());

        // Plan with undefined limit can't override
        assertOverrideFails(SubscriptionPlan.Builder
                .createRecurring(ZonedDateTime.parse("2007-03-14T00:00:00.000Z"),
                        Period.ofMonths(1))
                .setTitle("CTS")
                .build());

        // We can override when there is an active plan somewhere
        final SubscriptionPlan older = SubscriptionPlan.Builder
                .createNonrecurring(ZonedDateTime.now().minusDays(14),
                        ZonedDateTime.now().minusDays(7))
                .setTitle("CTS")
                .setDataLimit(1_000_000_000, SubscriptionPlan.LIMIT_BEHAVIOR_DISABLED)
                .build();
        final SubscriptionPlan newer = SubscriptionPlan.Builder
                .createNonrecurring(ZonedDateTime.now().minusDays(7),
                        ZonedDateTime.now().plusDays(7))
                .setTitle("CTS")
                .setDataLimit(1_000_000_000, SubscriptionPlan.LIMIT_BEHAVIOR_DISABLED)
                .build();
        assertOverrideSuccess(older, newer);
    }

    private void assertOverrideSuccess(SubscriptionPlan... plans) {
        mSm.setSubscriptionPlans(mSubId, Arrays.asList(plans));
        mSm.setSubscriptionOverrideCongested(mSubId, false, 0);
    }

    private void assertOverrideFails(SubscriptionPlan... plans) {
        mSm.setSubscriptionPlans(mSubId, Arrays.asList(plans));
        try {
            mSm.setSubscriptionOverrideCongested(mSubId, false, 0);
            fail();
        } catch (SecurityException | IllegalStateException expected) {
        }
    }

    public static CountDownLatch waitForNetworkCapabilities(Network network,
            Predicate<NetworkCapabilities> predicate) {
        final CountDownLatch latch = new CountDownLatch(1);
        final ConnectivityManager cm = InstrumentationRegistry.getContext()
                .getSystemService(ConnectivityManager.class);
        cm.registerNetworkCallback(new NetworkRequest.Builder().build(),
                new NetworkCallback() {
                    @Override
                    public void onCapabilitiesChanged(Network net, NetworkCapabilities caps) {
                        if (net.equals(network) && predicate.test(caps)) {
                            latch.countDown();
                            cm.unregisterNetworkCallback(this);
                        }
                    }
                });
        return latch;
    }

    private static SubscriptionPlan buildValidSubscriptionPlan() {
        return SubscriptionPlan.Builder
                .createRecurring(ZonedDateTime.parse("2007-03-14T00:00:00.000Z"),
                        Period.ofMonths(1))
                .setTitle("CTS")
                .setDataLimit(1_000_000_000, SubscriptionPlan.LIMIT_BEHAVIOR_DISABLED)
                .setDataUsage(500_000_000, System.currentTimeMillis())
                .build();
    }

    private static @Nullable Network findCellularNetwork() {
        final ConnectivityManager cm = InstrumentationRegistry.getContext()
                .getSystemService(ConnectivityManager.class);
        for (Network net : cm.getAllNetworks()) {
            final NetworkCapabilities caps = cm.getNetworkCapabilities(net);
            if (caps != null && caps.hasTransport(TRANSPORT_CELLULAR)
                    && caps.hasCapability(NET_CAPABILITY_INTERNET)
                    && caps.hasCapability(NET_CAPABILITY_NOT_RESTRICTED)) {
                return net;
            }
        }
        return null;
    }

    private static boolean isSupported() {
        return InstrumentationRegistry.getContext().getPackageManager()
                .hasSystemFeature(PackageManager.FEATURE_TELEPHONY);
    }

    private static void setSubPlanOwner(int subId, String packageName) throws Exception {
        SystemUtil.runShellCommand(InstrumentationRegistry.getInstrumentation(),
                "cmd netpolicy set sub-plan-owner " + subId + " " + packageName);
    }
}