/*
 * Copyright (C) 2020 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.location;

import android.annotation.NonNull;
import android.annotation.Nullable;
import android.location.util.identity.CallerIdentity;
import android.os.PackageTagsList;

/**
 * Location manager local system service interface.
 *
 * @hide Only for use within the system server.
 */
public abstract class LocationManagerInternal {

    /**
     * Listener for changes in provider enabled state.
     */
    public interface ProviderEnabledListener {
        /**
         * Called when the provider enabled state changes for a particular user.
         */
        void onProviderEnabledChanged(String provider, int userId, boolean enabled);
    }

    /**
     * Interface for getting callbacks when an app id's location provider package tags change.
     */
    public interface LocationPackageTagsListener {

        /**
         * Called when the package tags for a location provider change for a uid.
         */
        void onLocationPackageTagsChanged(int uid, @NonNull PackageTagsList packageTagsList);
    }

    /**
     * Returns true if the given provider is enabled for the given user.
     *
     * @param provider A location provider as listed by {@link LocationManager#getAllProviders()}
     * @param userId   The user id to check
     * @return True if the provider is enabled, false otherwise
     */
    public abstract boolean isProviderEnabledForUser(@NonNull String provider, int userId);

    /**
     * Adds a provider enabled listener. The given provider must exist.
     *
     * @param provider The provider to listen for changes
     * @param listener The listener
     */
    public abstract void addProviderEnabledListener(String provider,
            ProviderEnabledListener listener);

    /**
     * Removes a provider enabled listener. The given provider must exist.
     *
     * @param provider The provider to listen for changes
     * @param listener The listener
     */
    public abstract void removeProviderEnabledListener(String provider,
            ProviderEnabledListener listener);

    /**
     * Returns true if the given identity is a location provider.
     *
     * @param provider The provider to check, or null to check every provider
     * @param identity The identity to match
     * @return True if the given identity matches either the given location provider or any
     * provider, and false otherwise
     */
    public abstract boolean isProvider(@Nullable String provider, @NonNull CallerIdentity identity);

    /**
     * Returns the GNSS provided time.
     *
     * @return LocationTime object that includes the current time, according to the GNSS location
     * provider, and the elapsed nanos since boot the current time was computed at.
     */
    public abstract @Nullable LocationTime getGnssTimeMillis();

    /**
     * Sets a listener for changes in an app id's location provider package tags. Passing
     * {@code null} clears the current listener.
     */
    public abstract void setLocationPackageTagsListener(
            @Nullable LocationPackageTagsListener listener);
}