/**
 * 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.hardware.radio;

import android.annotation.NonNull;
import android.annotation.Nullable;
import android.os.Handler;
import android.os.Looper;
import android.util.Log;

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

/**
 * Implements the ITunerCallback interface by forwarding calls to RadioTuner.Callback.
 */
class TunerCallbackAdapter extends ITunerCallback.Stub {
    private static final String TAG = "BroadcastRadio.TunerCallbackAdapter";

    private final Object mLock = new Object();
    @NonNull private final RadioTuner.Callback mCallback;
    @NonNull private final Handler mHandler;

    @Nullable ProgramList mProgramList;
    @Nullable List<RadioManager.ProgramInfo> mLastCompleteList;  // for legacy getProgramList call
    private boolean mDelayedCompleteCallback = false;

    TunerCallbackAdapter(@NonNull RadioTuner.Callback callback, @Nullable Handler handler) {
        mCallback = callback;
        if (handler == null) {
            mHandler = new Handler(Looper.getMainLooper());
        } else {
            mHandler = handler;
        }
    }

    void setProgramListObserver(@Nullable ProgramList programList,
            @NonNull ProgramList.OnCloseListener closeListener) {
        Objects.requireNonNull(closeListener);
        synchronized (mLock) {
            if (mProgramList != null) {
                Log.w(TAG, "Previous program list observer wasn't properly closed, closing it...");
                mProgramList.close();
            }
            mProgramList = programList;
            if (programList == null) return;
            programList.setOnCloseListener(() -> {
                synchronized (mLock) {
                    if (mProgramList != programList) return;
                    mProgramList = null;
                    mLastCompleteList = null;
                    closeListener.onClose();
                }
            });
            programList.addOnCompleteListener(() -> {
                synchronized (mLock) {
                    if (mProgramList != programList) return;
                    mLastCompleteList = programList.toList();
                    if (mDelayedCompleteCallback) {
                        Log.d(TAG, "Sending delayed onBackgroundScanComplete callback");
                        sendBackgroundScanCompleteLocked();
                    }
                }
            });
        }
    }

    @Nullable List<RadioManager.ProgramInfo> getLastCompleteList() {
        synchronized (mLock) {
            return mLastCompleteList;
        }
    }

    void clearLastCompleteList() {
        synchronized (mLock) {
            mLastCompleteList = null;
        }
    }

    @Override
    public void onError(int status) {
        mHandler.post(() -> mCallback.onError(status));
    }

    @Override
    public void onConfigurationChanged(RadioManager.BandConfig config) {
        mHandler.post(() -> mCallback.onConfigurationChanged(config));
    }

    @Override
    public void onCurrentProgramInfoChanged(RadioManager.ProgramInfo info) {
        if (info == null) {
            Log.e(TAG, "ProgramInfo must not be null");
            return;
        }

        mHandler.post(() -> {
            mCallback.onProgramInfoChanged(info);

            RadioMetadata metadata = info.getMetadata();
            if (metadata != null) mCallback.onMetadataChanged(metadata);
        });
    }

    @Override
    public void onTrafficAnnouncement(boolean active) {
        mHandler.post(() -> mCallback.onTrafficAnnouncement(active));
    }

    @Override
    public void onEmergencyAnnouncement(boolean active) {
        mHandler.post(() -> mCallback.onEmergencyAnnouncement(active));
    }

    @Override
    public void onAntennaState(boolean connected) {
        mHandler.post(() -> mCallback.onAntennaState(connected));
    }

    @Override
    public void onBackgroundScanAvailabilityChange(boolean isAvailable) {
        mHandler.post(() -> mCallback.onBackgroundScanAvailabilityChange(isAvailable));
    }

    private void sendBackgroundScanCompleteLocked() {
        mDelayedCompleteCallback = false;
        mHandler.post(() -> mCallback.onBackgroundScanComplete());
    }

    @Override
    public void onBackgroundScanComplete() {
        synchronized (mLock) {
            if (mLastCompleteList == null) {
                Log.i(TAG, "Got onBackgroundScanComplete callback, but the "
                        + "program list didn't get through yet. Delaying it...");
                mDelayedCompleteCallback = true;
                return;
            }
            sendBackgroundScanCompleteLocked();
        }
    }

    @Override
    public void onProgramListChanged() {
        mHandler.post(() -> mCallback.onProgramListChanged());
    }

    @Override
    public void onProgramListUpdated(ProgramList.Chunk chunk) {
        synchronized (mLock) {
            if (mProgramList == null) return;
            mProgramList.apply(Objects.requireNonNull(chunk));
        }
    }

    @Override
    public void onParametersUpdated(Map parameters) {
        mHandler.post(() -> mCallback.onParametersUpdated(parameters));
    }
}