/*
 * Copyright (C) 2017 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.ims;

import android.annotation.SystemApi;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.os.RemoteException;
import android.telephony.CarrierConfigManager;
import android.telephony.ims.aidl.IImsConfig;
import android.telephony.ims.aidl.IImsMmTelFeature;
import android.telephony.ims.aidl.IImsRcsFeature;
import android.telephony.ims.aidl.IImsRegistration;
import android.telephony.ims.aidl.IImsServiceController;
import android.telephony.ims.aidl.IImsServiceControllerListener;
import android.telephony.ims.feature.ImsFeature;
import android.telephony.ims.feature.MmTelFeature;
import android.telephony.ims.feature.RcsFeature;
import android.telephony.ims.stub.ImsConfigImplBase;
import android.telephony.ims.stub.ImsFeatureConfiguration;
import android.telephony.ims.stub.ImsRegistrationImplBase;
import android.util.Log;
import android.util.SparseArray;

import com.android.ims.internal.IImsFeatureStatusCallback;
import com.android.internal.annotations.VisibleForTesting;

import static android.Manifest.permission.MODIFY_PHONE_STATE;

Main ImsService implementation, which binds via the Telephony ImsResolver. Services that extend
ImsService must register the service in their AndroidManifest to be detected by the framework.
First, the application must declare that they use the "android.permission.BIND_IMS_SERVICE"
permission. Then, the ImsService definition in the manifest must follow the following format:
...

    ...
    
        
    
 ... The telephony framework will then bind to the ImsService you have defined in your manifest if you are either: 1) Defined as the default ImsService for the device in the device overlay using "config_ims_package". 2) Defined as a Carrier Provided ImsService in the Carrier Configuration using CarrierConfigManager.KEY_CONFIG_IMS_PACKAGE_OVERRIDE_STRING. There are two ways to define to the platform which ImsFeatures this ImsService supports, dynamic or static definitions. In the static definition, the ImsFeatures that are supported are defined in the service definition of the AndroidManifest.xml file as metadata: 
 The features that are currently supported in an ImsService are: - RCS_FEATURE: This ImsService implements the RcsFeature class. - MMTEL_FEATURE: This ImsService implements the MmTelFeature class. - EMERGENCY_MMTEL_FEATURE: This ImsService supports Emergency Calling for MMTEL, must be declared along with the MMTEL_FEATURE. If this is not specified, the framework will use circuit switch for emergency calling. In the dynamic definition, the supported features are not specified in the service definition of the AndroidManifest. Instead, the framework binds to this service and calls querySupportedImsFeatures(). The ImsService then returns an ImsFeatureConfiguration, which the framework uses to initialize the supported ImsFeatures. If at any time, the list of supported ImsFeatures changes, onUpdateSupportedImsFeatures(ImsFeatureConfiguration) can be called to tell the framework of the changes. 
@hide
/**
 * Main ImsService implementation, which binds via the Telephony ImsResolver. Services that extend
 * ImsService must register the service in their AndroidManifest to be detected by the framework.
 * First, the application must declare that they use the "android.permission.BIND_IMS_SERVICE"
 * permission. Then, the ImsService definition in the manifest must follow the following format:
 *
 * ...
 * <service android:name=".EgImsService"
 *     android:permission="android.permission.BIND_IMS_SERVICE" >
 *     ...
 *     <intent-filter>
 *         <action android:name="android.telephony.ims.ImsService" />
 *     </intent-filter>
 * </service>
 * ...
 *
 * The telephony framework will then bind to the ImsService you have defined in your manifest
 * if you are either:
 * 1) Defined as the default ImsService for the device in the device overlay using
 *    "config_ims_package".
 * 2) Defined as a Carrier Provided ImsService in the Carrier Configuration using
 *    {@link CarrierConfigManager#KEY_CONFIG_IMS_PACKAGE_OVERRIDE_STRING}.
 *
 * There are two ways to define to the platform which {@link ImsFeature}s this {@link ImsService}
 * supports, dynamic or static definitions.
 *
 * In the static definition, the {@link ImsFeature}s that are supported are defined in the service
 * definition of the AndroidManifest.xml file as metadata:
 * <!-- Apps must declare which features they support as metadata. The different categories are
 *      defined below. In this example, the MMTEL_FEATURE feature is supported. -->
 * <meta-data android:name="android.telephony.ims.MMTEL_FEATURE" android:value="true" />
 *
 * The features that are currently supported in an ImsService are:
 * - RCS_FEATURE: This ImsService implements the RcsFeature class.
 * - MMTEL_FEATURE: This ImsService implements the MmTelFeature class.
 * - EMERGENCY_MMTEL_FEATURE: This ImsService supports Emergency Calling for MMTEL, must be
 *   declared along with the MMTEL_FEATURE. If this is not specified, the framework will use
 *   circuit switch for emergency calling.
 *
 * In the dynamic definition, the supported features are not specified in the service definition
 * of the AndroidManifest. Instead, the framework binds to this service and calls
 * {@link #querySupportedImsFeatures()}. The {@link ImsService} then returns an
 * {@link ImsFeatureConfiguration}, which the framework uses to initialize the supported
 * {@link ImsFeature}s. If at any time, the list of supported {@link ImsFeature}s changes,
 * {@link #onUpdateSupportedImsFeatures(ImsFeatureConfiguration)} can be called to tell the
 * framework of the changes.
 *
 * @hide
 */
@SystemApi
public class ImsService extends Service {

    private static final String LOG_TAG = "ImsService";

    
The intent that must be defined as an intent-filter in the AndroidManifest of the ImsService.
@hide
/**
     * The intent that must be defined as an intent-filter in the AndroidManifest of the ImsService.
     * @hide
     */
    public static final String SERVICE_INTERFACE = "android.telephony.ims.ImsService";

    // A map of slot Id -> map of features (indexed by ImsFeature feature id) corresponding to that
    // slot.
    // We keep track of this to facilitate cleanup of the IImsFeatureStatusCallback and
    // call ImsFeature#onFeatureRemoved.
    private final SparseArray<SparseArray<ImsFeature>> mFeaturesBySlot = new SparseArray<>();

    private IImsServiceControllerListener mListener;


    
Listener that notifies the framework of ImsService changes.
@hide
/**
     * Listener that notifies the framework of ImsService changes.
     * @hide
     */
    public static class Listener extends IImsServiceControllerListener.Stub {
        
The IMS features that this ImsService supports has changed.
Params:
c – a new ImsFeatureConfiguration containing FeatureTypes that this ImsService supports. This may trigger the addition/removal of feature in this service./**
         * The IMS features that this ImsService supports has changed.
         * @param c a new {@link ImsFeatureConfiguration} containing {@link ImsFeature.FeatureType}s
         *   that this ImsService supports. This may trigger the addition/removal of feature
         *   in this service.
         */
        public void onUpdateSupportedImsFeatures(ImsFeatureConfiguration c) {
        }
    }

    
@hide
/**
     * @hide
     */
    protected final IBinder mImsServiceController = new IImsServiceController.Stub() {
        @Override
        public void setListener(IImsServiceControllerListener l) {
            mListener = l;
        }

        @Override
        public IImsMmTelFeature createMmTelFeature(int slotId, IImsFeatureStatusCallback c) {
            return createMmTelFeatureInternal(slotId, c);
        }

        @Override
        public IImsRcsFeature createRcsFeature(int slotId, IImsFeatureStatusCallback c) {
            return createRcsFeatureInternal(slotId, c);
        }

        @Override
        public void removeImsFeature(int slotId, int featureType, IImsFeatureStatusCallback c) {
            ImsService.this.removeImsFeature(slotId, featureType, c);
        }

        @Override
        public ImsFeatureConfiguration querySupportedImsFeatures() {
            return ImsService.this.querySupportedImsFeatures();
        }

        @Override
        public void notifyImsServiceReadyForFeatureCreation() {
            ImsService.this.readyForFeatureCreation();
        }

        @Override
        public IImsConfig getConfig(int slotId) {
            ImsConfigImplBase c = ImsService.this.getConfig(slotId);
            return c != null ? c.getIImsConfig() : null;
        }

        @Override
        public IImsRegistration getRegistration(int slotId) {
            ImsRegistrationImplBase r = ImsService.this.getRegistration(slotId);
            return r != null ? r.getBinder() : null;
        }

        @Override
        public void enableIms(int slotId) {
            ImsService.this.enableIms(slotId);
        }

        @Override
        public void disableIms(int slotId) {
            ImsService.this.disableIms(slotId);
        }
    };

    
@hide
/**
     * @hide
     */
    @Override
    public IBinder onBind(Intent intent) {
        if(SERVICE_INTERFACE.equals(intent.getAction())) {
            Log.i(LOG_TAG, "ImsService Bound.");
            return mImsServiceController;
        }
        return null;
    }

    
@hide
/**
     * @hide
     */
    @VisibleForTesting
    public SparseArray<ImsFeature> getFeatures(int slotId) {
        return mFeaturesBySlot.get(slotId);
    }

    private IImsMmTelFeature createMmTelFeatureInternal(int slotId,
            IImsFeatureStatusCallback c) {
        MmTelFeature f = createMmTelFeature(slotId);
        if (f != null) {
            setupFeature(f, slotId, ImsFeature.FEATURE_MMTEL, c);
            return f.getBinder();
        } else {
            Log.e(LOG_TAG, "createMmTelFeatureInternal: null feature returned.");
            return null;
        }
    }

    private IImsRcsFeature createRcsFeatureInternal(int slotId,
            IImsFeatureStatusCallback c) {
        RcsFeature f = createRcsFeature(slotId);
        if (f != null) {
            setupFeature(f, slotId, ImsFeature.FEATURE_RCS, c);
            return f.getBinder();
        } else {
            Log.e(LOG_TAG, "createRcsFeatureInternal: null feature returned.");
            return null;
        }
    }

    private void setupFeature(ImsFeature f, int slotId, int featureType,
            IImsFeatureStatusCallback c) {
        f.addImsFeatureStatusCallback(c);
        f.initialize(this, slotId);
        addImsFeature(slotId, featureType, f);
    }

    private void addImsFeature(int slotId, int featureType, ImsFeature f) {
        synchronized (mFeaturesBySlot) {
            // Get SparseArray for Features, by querying slot Id
            SparseArray<ImsFeature> features = mFeaturesBySlot.get(slotId);
            if (features == null) {
                // Populate new SparseArray of features if it doesn't exist for this slot yet.
                features = new SparseArray<>();
                mFeaturesBySlot.put(slotId, features);
            }
            features.put(featureType, f);
        }
    }

    private void removeImsFeature(int slotId, int featureType,
            IImsFeatureStatusCallback c) {
        synchronized (mFeaturesBySlot) {
            // get ImsFeature associated with the slot/feature
            SparseArray<ImsFeature> features = mFeaturesBySlot.get(slotId);
            if (features == null) {
                Log.w(LOG_TAG, "Can not remove ImsFeature. No ImsFeatures exist on slot "
                        + slotId);
                return;
            }
            ImsFeature f = features.get(featureType);
            if (f == null) {
                Log.w(LOG_TAG, "Can not remove ImsFeature. No feature with type "
                        + featureType + " exists on slot " + slotId);
                return;
            }
            f.removeImsFeatureStatusCallback(c);
            f.onFeatureRemoved();
            features.remove(featureType);
        }
    }

    
When called, provide the ImsFeatureConfiguration that this ImsService currently supports. This will trigger the framework to set up the ImsFeatures that correspond to the ImsFeatures configured here. Use onUpdateSupportedImsFeatures(ImsFeatureConfiguration) to change the supported ImsFeatures. 
Returns:
an ImsFeatureConfiguration containing Features this ImsService supports./**
     * When called, provide the {@link ImsFeatureConfiguration} that this {@link ImsService}
     * currently supports. This will trigger the framework to set up the {@link ImsFeature}s that
     * correspond to the {@link ImsFeature}s configured here.
     *
     * Use {@link #onUpdateSupportedImsFeatures(ImsFeatureConfiguration)} to change the supported
     * {@link ImsFeature}s.
     *
     * @return an {@link ImsFeatureConfiguration} containing Features this ImsService supports.
     */
    public ImsFeatureConfiguration querySupportedImsFeatures() {
        // Return empty for base implementation
        return new ImsFeatureConfiguration();
    }

    
Updates the framework with a new ImsFeatureConfiguration containing the updated features, that this ImsService supports. This may trigger the framework to add/remove new ImsFeatures, depending on the configuration. /**
     * Updates the framework with a new {@link ImsFeatureConfiguration} containing the updated
     * features, that this {@link ImsService} supports. This may trigger the framework to add/remove
     * new ImsFeatures, depending on the configuration.
     */
    public final void onUpdateSupportedImsFeatures(ImsFeatureConfiguration c)
            throws RemoteException {
        if (mListener == null) {
            throw new IllegalStateException("Framework is not ready");
        }
        mListener.onUpdateSupportedImsFeatures(c);
    }

    
The ImsService has been bound and is ready for ImsFeature creation based on the Features that the ImsService has registered for with the framework, either in the manifest or via querySupportedImsFeatures(). The ImsService should use this signal instead of onCreate/onBind or similar to perform feature initialization because the framework may bind to this service multiple times to query the ImsService's ImsFeatureConfiguration via querySupportedImsFeatures()before creating features. /**
     * The ImsService has been bound and is ready for ImsFeature creation based on the Features that
     * the ImsService has registered for with the framework, either in the manifest or via
     * {@link #querySupportedImsFeatures()}.
     *
     * The ImsService should use this signal instead of onCreate/onBind or similar to perform
     * feature initialization because the framework may bind to this service multiple times to
     * query the ImsService's {@link ImsFeatureConfiguration} via
     * {@link #querySupportedImsFeatures()}before creating features.
     */
    public void readyForFeatureCreation() {
    }

    
The framework has enabled IMS for the slot specified, the ImsService should register for IMS
and perform all appropriate initialization to bring up all ImsFeatures.
/**
     * The framework has enabled IMS for the slot specified, the ImsService should register for IMS
     * and perform all appropriate initialization to bring up all ImsFeatures.
     */
    public void enableIms(int slotId) {
    }

    
The framework has disabled IMS for the slot specified. The ImsService must deregister for IMS
and set capability status to false for all ImsFeatures.
/**
     * The framework has disabled IMS for the slot specified. The ImsService must deregister for IMS
     * and set capability status to false for all ImsFeatures.
     */
    public void disableIms(int slotId) {
    }

    
When called, the framework is requesting that a new MmTelFeature is created for the specified slot. 
Params:
slotId – The slot ID that the MMTEL Feature is being created for.
Returns:
The newly created MmTelFeature associated with the slot or null if the feature is not supported./**
     * When called, the framework is requesting that a new {@link MmTelFeature} is created for the
     * specified slot.
     *
     * @param slotId The slot ID that the MMTEL Feature is being created for.
     * @return The newly created {@link MmTelFeature} associated with the slot or null if the
     * feature is not supported.
     */
    public MmTelFeature createMmTelFeature(int slotId) {
        return null;
    }

    
When called, the framework is requesting that a new RcsFeature is created for the specified slot. 
Params:
slotId – The slot ID that the RCS Feature is being created for.
Returns:
The newly created RcsFeature associated with the slot or null if the feature is not supported./**
     * When called, the framework is requesting that a new {@link RcsFeature} is created for the
     * specified slot.
     *
     * @param slotId The slot ID that the RCS Feature is being created for.
     * @return The newly created {@link RcsFeature} associated with the slot or null if the feature
     * is not supported.
     */
    public RcsFeature createRcsFeature(int slotId) {
        return null;
    }

    
Return the ImsConfigImplBase implementation associated with the provided slot. This will be used by the platform to get/set specific IMS related configurations. 
Params:
slotId – The slot that the IMS configuration is associated with.
Returns:
ImsConfig implementation that is associated with the specified slot./**
     * Return the {@link ImsConfigImplBase} implementation associated with the provided slot. This
     * will be used by the platform to get/set specific IMS related configurations.
     *
     * @param slotId The slot that the IMS configuration is associated with.
     * @return ImsConfig implementation that is associated with the specified slot.
     */
    public ImsConfigImplBase getConfig(int slotId) {
        return new ImsConfigImplBase();
    }

    
Return the ImsRegistrationImplBase implementation associated with the provided slot. 
Params:
slotId – The slot that is associated with the IMS Registration.
Returns:
the ImsRegistration implementation associated with the slot./**
     * Return the {@link ImsRegistrationImplBase} implementation associated with the provided slot.
     *
     * @param slotId The slot that is associated with the IMS Registration.
     * @return the ImsRegistration implementation associated with the slot.
     */
    public ImsRegistrationImplBase getRegistration(int slotId) {
        return new ImsRegistrationImplBase();
    }
}