/*
 * Copyright (C) 2021 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.car.audio;

import static android.car.builtin.media.AudioManagerHelper.adjustToString;
import static android.car.media.CarAudioManager.INVALID_VOLUME_GROUP_ID;
import static android.car.media.CarAudioManager.PRIMARY_AUDIO_ZONE;
import static android.media.AudioManager.ADJUST_LOWER;
import static android.media.AudioManager.ADJUST_MUTE;
import static android.media.AudioManager.ADJUST_RAISE;
import static android.media.AudioManager.ADJUST_SAME;
import static android.media.AudioManager.ADJUST_TOGGLE_MUTE;
import static android.media.AudioManager.ADJUST_UNMUTE;
import static android.media.AudioManager.FLAG_FROM_KEY;
import static android.media.AudioManager.FLAG_SHOW_UI;
import static android.util.Log.VERBOSE;

import static com.android.car.CarLog.TAG_AUDIO;

import android.car.builtin.util.Slogf;
import android.car.media.CarVolumeGroupInfo;
import android.car.oem.OemCarAudioVolumeRequest;
import android.car.oem.OemCarVolumeChangeInfo;
import android.media.AudioAttributes;
import android.media.audiopolicy.AudioPolicy;
import android.util.Log;

import com.android.car.CarLocalServices;
import com.android.car.oem.CarOemProxyService;

import java.util.List;
import java.util.Objects;

final class CarAudioPolicyVolumeCallback extends AudioPolicy.AudioPolicyVolumeCallback {

    public static final boolean DEBUG = Slogf.isLoggable(TAG_AUDIO, Log.DEBUG);

    private final AudioManagerWrapper mAudioManager;
    private final boolean mUseCarVolumeGroupMuting;
    private final AudioPolicyVolumeCallbackInternal mVolumeCallback;
    private final CarVolumeInfoWrapper mCarVolumeInfo;

    static void addVolumeCallbackToPolicy(AudioPolicy.Builder policyBuilder,
            CarAudioPolicyVolumeCallback callback) {
        Objects.requireNonNull(policyBuilder, "AudioPolicy.Builder cannot be null");
        policyBuilder.setAudioPolicyVolumeCallback(callback);
        if (DEBUG) {
            Slogf.d(TAG_AUDIO, "Registered car audio policy volume callback");
        }
    }

    CarAudioPolicyVolumeCallback(AudioPolicyVolumeCallbackInternal volumeCallback,
            AudioManagerWrapper audioManager, CarVolumeInfoWrapper carVolumeInfo,
            boolean useCarVolumeGroupMuting) {
        mVolumeCallback = Objects.requireNonNull(volumeCallback, "Volume Callback cannot be null");
        mAudioManager = Objects.requireNonNull(audioManager, "AudioManager cannot be null");
        mCarVolumeInfo = Objects.requireNonNull(carVolumeInfo, "Volume Info cannot be null");
        mUseCarVolumeGroupMuting = useCarVolumeGroupMuting;
    }

    void onVolumeAdjustment(int adjustment, int zoneId) {
        if (isOemDuckingServiceAvailable()) {
            evaluateVolumeAdjustmentExternal(adjustment, zoneId);
            return;
        }
        evaluateVolumeAdjustmentInternal(adjustment, zoneId);
    }

    private void evaluateVolumeAdjustmentExternal(int adjustment, int zoneId) {
        OemCarAudioVolumeRequest request = getCarAudioVolumeRequest(zoneId);

        if (DEBUG) {
            Slogf.d(TAG_AUDIO, "evaluateVolumeAdjustmentExternal %s", request);
        }

        OemCarVolumeChangeInfo changedVolume =
                CarLocalServices.getService(CarOemProxyService.class)
                        .getCarOemAudioVolumeService()
                        .getSuggestedGroupForVolumeChange(request, adjustment);

        if (changedVolume == null || !changedVolume.isVolumeChanged()) {
            if (DEBUG) {
                Slogf.d(TAG_AUDIO, "No volume change for adjustment %s in zone %s",
                        adjustToString(adjustment), zoneId);
            }
            return;
        }

        CarVolumeGroupInfo info = changedVolume.getChangedVolumeGroup();
        int flags = FLAG_FROM_KEY | FLAG_SHOW_UI;

        switch (adjustment) {
            case ADJUST_LOWER: // Fallthrough
            case ADJUST_RAISE:
                mVolumeCallback.onGroupVolumeChange(info.getZoneId(), info.getId(),
                        info.getVolumeGainIndex(), flags);
                break;
            case ADJUST_MUTE: // Fallthrough
            case ADJUST_UNMUTE: // Fallthrough
            case ADJUST_TOGGLE_MUTE:
                mVolumeCallback.onMuteChange(info.isMuted(), info.getZoneId(), info.getId(), flags);
                break;
            case ADJUST_SAME: // Fallthrough
            default:
                // There should be a change in volume info, compare against the current one
                CarVolumeGroupInfo currentInfo =
                        mCarVolumeInfo.getVolumeGroupInfo(info.getZoneId(), info.getId());
                if (info.isMuted() != currentInfo.isMuted()) {
                    mVolumeCallback.onMuteChange(info.isMuted(), info.getZoneId(),
                            info.getId(), flags);
                }
                if (info.getVolumeGainIndex() != currentInfo.getVolumeGainIndex()) {
                    mVolumeCallback.onGroupVolumeChange(info.getZoneId(),
                            info.getId(), info.getVolumeGainIndex(), flags);
                }
                break;
        }
    }

    private OemCarAudioVolumeRequest getCarAudioVolumeRequest(int zoneId) {
        List<CarVolumeGroupInfo> infos = mCarVolumeInfo.getVolumeGroupInfosForZone(zoneId);
        List<AudioAttributes> activeAudioAttributes =
                mCarVolumeInfo.getActiveAudioAttributesForZone(zoneId);

        return new OemCarAudioVolumeRequest.Builder(zoneId)
                .setCarVolumeGroupInfos(infos)
                .setActivePlaybackAttributes(activeAudioAttributes)
                .setCallState(mCarVolumeInfo.getCallStateForZone(zoneId))
                .build();
    }

    private void evaluateVolumeAdjustmentInternal(int adjustment, int zoneId) {
        int groupId = mCarVolumeInfo.getVolumeGroupIdForAudioZone(zoneId);
        if (groupId == INVALID_VOLUME_GROUP_ID) {
            // This can happen if all volume groups are configured with dynamic devices and the
            // configuration to allow volume key events to dynamic devices is disabled.
            Slogf.w(TAG_AUDIO, "onVolumeAdjustment: %s but no suitable volume group id was found.",
                    adjustToString(adjustment));
            return;
        }
        boolean isMuted = isMuted(zoneId, groupId);

        if (Slogf.isLoggable(TAG_AUDIO, VERBOSE)) {
            Slogf.v(TAG_AUDIO,
                    "onVolumeAdjustment: %s suggested volume group: %s is muted: %b",
                    adjustToString(adjustment),
                    groupId, isMuted);
        }

        int currentVolume = mCarVolumeInfo.getGroupVolume(zoneId, groupId);
        int flags = FLAG_FROM_KEY | FLAG_SHOW_UI;
        int minGain = mCarVolumeInfo.getGroupMinVolume(zoneId, groupId);
        switch (adjustment) {
            case ADJUST_LOWER:
                int minValue = Math.max(currentVolume - 1, minGain);
                if (isMuted)  {
                    minValue = minGain;
                }
                mVolumeCallback.onGroupVolumeChange(zoneId, groupId, minValue, flags);
                break;
            case ADJUST_RAISE:
                int maxValue = Math.min(currentVolume + 1,
                        mCarVolumeInfo.getGroupMaxVolume(zoneId, groupId));
                if (isMuted)  {
                    maxValue = minGain;
                }
                mVolumeCallback.onGroupVolumeChange(zoneId, groupId, maxValue, flags);
                break;
            case ADJUST_MUTE:
            case ADJUST_UNMUTE:
                mVolumeCallback.onMuteChange(adjustment == ADJUST_MUTE, zoneId, groupId, flags);
                break;
            case ADJUST_TOGGLE_MUTE:
                mVolumeCallback.onMuteChange(!isMuted, zoneId, groupId, flags);
                break;
            case ADJUST_SAME:
            default:
                break;
        }
    }

    @Override
    public void onVolumeAdjustment(int adjustment) {
        onVolumeAdjustment(adjustment, PRIMARY_AUDIO_ZONE);
    }

    private boolean isMuted(int zoneId, int groupId) {
        if (mUseCarVolumeGroupMuting) {
            return mCarVolumeInfo.isVolumeGroupMuted(zoneId, groupId);
        }
        return mAudioManager.isMasterMuted();
    }

    private boolean isOemDuckingServiceAvailable() {
        CarOemProxyService carService = CarLocalServices.getService(CarOemProxyService.class);

        return carService != null
                && carService.isOemServiceEnabled() && carService.isOemServiceReady()
                && carService.getCarOemAudioVolumeService() != null;
    }

    public interface AudioPolicyVolumeCallbackInternal {

        /**
         * Called when on volume key event has triggered a mute change for a particular volume group
         */
        void onMuteChange(boolean mute, int zoneId, int groupId, int flags);

        /**
         * Called when on volume key event has triggered a volume
         * change for a particular volume group
         */
        void onGroupVolumeChange(int zoneId, int groupId, int volumeValue, int flags);
    }
}