/*
 *  Copyright 2018 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

package org.webrtc.audio;

import android.content.Context;
import android.media.AudioAttributes;
import android.media.AudioDeviceInfo;
import android.media.AudioManager;
import android.os.Build;
import android.support.annotation.RequiresApi;
import java.util.concurrent.ScheduledExecutorService;
import org.webrtc.JniCommon;
import org.webrtc.Logging;

/**
 * AudioDeviceModule implemented using android.media.AudioRecord as input and
 * android.media.AudioTrack as output.
 */
public class JavaAudioDeviceModule implements AudioDeviceModule {
  private static final String TAG = "JavaAudioDeviceModule";

  public static Builder builder(Context context) {
    return new Builder(context);
  }

  public static class Builder {
    private final Context context;
    private ScheduledExecutorService scheduler;
    private final AudioManager audioManager;
    private int inputSampleRate;
    private int outputSampleRate;
    private int audioSource = WebRtcAudioRecord.DEFAULT_AUDIO_SOURCE;
    private int audioFormat = WebRtcAudioRecord.DEFAULT_AUDIO_FORMAT;
    private AudioTrackErrorCallback audioTrackErrorCallback;
    private AudioRecordErrorCallback audioRecordErrorCallback;
    private SamplesReadyCallback samplesReadyCallback;
    private AudioTrackStateCallback audioTrackStateCallback;
    private AudioRecordStateCallback audioRecordStateCallback;
    private boolean useHardwareAcousticEchoCanceler = isBuiltInAcousticEchoCancelerSupported();
    private boolean useHardwareNoiseSuppressor = isBuiltInNoiseSuppressorSupported();
    private boolean useStereoInput;
    private boolean useStereoOutput;
    private AudioAttributes audioAttributes;
    private boolean useLowLatency;

    private Builder(Context context) {
      this.context = context;
      this.audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
      this.inputSampleRate = WebRtcAudioManager.getSampleRate(audioManager);
      this.outputSampleRate = WebRtcAudioManager.getSampleRate(audioManager);
      this.useLowLatency = false;
    }

    public Builder setScheduler(ScheduledExecutorService scheduler) {
      this.scheduler = scheduler;
      return this;
    }

    /**
     * Call this method if the default handling of querying the native sample rate shall be
     * overridden. Can be useful on some devices where the available Android APIs are known to
     * return invalid results.
     */
    public Builder setSampleRate(int sampleRate) {
      Logging.d(TAG, "Input/Output sample rate overridden to: " + sampleRate);
      this.inputSampleRate = sampleRate;
      this.outputSampleRate = sampleRate;
      return this;
    }

    /**
     * Call this method to specifically override input sample rate.
     */
    public Builder setInputSampleRate(int inputSampleRate) {
      Logging.d(TAG, "Input sample rate overridden to: " + inputSampleRate);
      this.inputSampleRate = inputSampleRate;
      return this;
    }

    /**
     * Call this method to specifically override output sample rate.
     */
    public Builder setOutputSampleRate(int outputSampleRate) {
      Logging.d(TAG, "Output sample rate overridden to: " + outputSampleRate);
      this.outputSampleRate = outputSampleRate;
      return this;
    }

    /**
     * Call this to change the audio source. The argument should be one of the values from
     * android.media.MediaRecorder.AudioSource. The default is AudioSource.VOICE_COMMUNICATION.
     */
    public Builder setAudioSource(int audioSource) {
      this.audioSource = audioSource;
      return this;
    }

    /**
     * Call this to change the audio format. The argument should be one of the values from
     * android.media.AudioFormat ENCODING_PCM_8BIT, ENCODING_PCM_16BIT or ENCODING_PCM_FLOAT.
     * Default audio data format is PCM 16 bit per sample.
     * Guaranteed to be supported by all devices.
     */
    public Builder setAudioFormat(int audioFormat) {
      this.audioFormat = audioFormat;
      return this;
    }

    /**
     * Set a callback to retrieve errors from the AudioTrack.
     */
    public Builder setAudioTrackErrorCallback(AudioTrackErrorCallback audioTrackErrorCallback) {
      this.audioTrackErrorCallback = audioTrackErrorCallback;
      return this;
    }

    /**
     * Set a callback to retrieve errors from the AudioRecord.
     */
    public Builder setAudioRecordErrorCallback(AudioRecordErrorCallback audioRecordErrorCallback) {
      this.audioRecordErrorCallback = audioRecordErrorCallback;
      return this;
    }

    /**
     * Set a callback to listen to the raw audio input from the AudioRecord.
     */
    public Builder setSamplesReadyCallback(SamplesReadyCallback samplesReadyCallback) {
      this.samplesReadyCallback = samplesReadyCallback;
      return this;
    }

    /**
     * Set a callback to retrieve information from the AudioTrack on when audio starts and stop.
     */
    public Builder setAudioTrackStateCallback(AudioTrackStateCallback audioTrackStateCallback) {
      this.audioTrackStateCallback = audioTrackStateCallback;
      return this;
    }

    /**
     * Set a callback to retrieve information from the AudioRecord on when audio starts and stops.
     */
    public Builder setAudioRecordStateCallback(AudioRecordStateCallback audioRecordStateCallback) {
      this.audioRecordStateCallback = audioRecordStateCallback;
      return this;
    }

    /**
     * Control if the built-in HW noise suppressor should be used or not. The default is on if it is
     * supported. It is possible to query support by calling isBuiltInNoiseSuppressorSupported().
     */
    public Builder setUseHardwareNoiseSuppressor(boolean useHardwareNoiseSuppressor) {
      if (useHardwareNoiseSuppressor && !isBuiltInNoiseSuppressorSupported()) {
        Logging.e(TAG, "HW NS not supported");
        useHardwareNoiseSuppressor = false;
      }
      this.useHardwareNoiseSuppressor = useHardwareNoiseSuppressor;
      return this;
    }

    /**
     * Control if the built-in HW acoustic echo canceler should be used or not. The default is on if
     * it is supported. It is possible to query support by calling
     * isBuiltInAcousticEchoCancelerSupported().
     */
    public Builder setUseHardwareAcousticEchoCanceler(boolean useHardwareAcousticEchoCanceler) {
      if (useHardwareAcousticEchoCanceler && !isBuiltInAcousticEchoCancelerSupported()) {
        Logging.e(TAG, "HW AEC not supported");
        useHardwareAcousticEchoCanceler = false;
      }
      this.useHardwareAcousticEchoCanceler = useHardwareAcousticEchoCanceler;
      return this;
    }

    /**
     * Control if stereo input should be used or not. The default is mono.
     */
    public Builder setUseStereoInput(boolean useStereoInput) {
      this.useStereoInput = useStereoInput;
      return this;
    }

    /**
     * Control if stereo output should be used or not. The default is mono.
     */
    public Builder setUseStereoOutput(boolean useStereoOutput) {
      this.useStereoOutput = useStereoOutput;
      return this;
    }

    /**
     * Control if the low-latency mode should be used. The default is disabled.
     */
    public Builder setUseLowLatency(boolean useLowLatency) {
      this.useLowLatency = useLowLatency;
      return this;
    }

    /**
     * Set custom {@link AudioAttributes} to use.
     */
    public Builder setAudioAttributes(AudioAttributes audioAttributes) {
      this.audioAttributes = audioAttributes;
      return this;
    }

    /**
     * Construct an AudioDeviceModule based on the supplied arguments. The caller takes ownership
     * and is responsible for calling release().
     */
    public JavaAudioDeviceModule createAudioDeviceModule() {
      Logging.d(TAG, "createAudioDeviceModule");
      if (useHardwareNoiseSuppressor) {
        Logging.d(TAG, "HW NS will be used.");
      } else {
        if (isBuiltInNoiseSuppressorSupported()) {
          Logging.d(TAG, "Overriding default behavior; now using WebRTC NS!");
        }
        Logging.d(TAG, "HW NS will not be used.");
      }
      if (useHardwareAcousticEchoCanceler) {
        Logging.d(TAG, "HW AEC will be used.");
      } else {
        if (isBuiltInAcousticEchoCancelerSupported()) {
          Logging.d(TAG, "Overriding default behavior; now using WebRTC AEC!");
        }
        Logging.d(TAG, "HW AEC will not be used.");
      }
      // Low-latency mode was introduced in API version 26, see
      // https://developer.android.com/reference/android/media/AudioTrack#PERFORMANCE_MODE_LOW_LATENCY
      final int MIN_LOW_LATENCY_SDK_VERSION = 26;
      if (useLowLatency && Build.VERSION.SDK_INT >= MIN_LOW_LATENCY_SDK_VERSION) {
        Logging.d(TAG, "Low latency mode will be used.");
      }
      ScheduledExecutorService executor = this.scheduler;
      if (executor == null) {
        executor = WebRtcAudioRecord.newDefaultScheduler();
      }
      final WebRtcAudioRecord audioInput = new WebRtcAudioRecord(context, executor, audioManager,
          audioSource, audioFormat, audioRecordErrorCallback, audioRecordStateCallback,
          samplesReadyCallback, useHardwareAcousticEchoCanceler, useHardwareNoiseSuppressor);
      final WebRtcAudioTrack audioOutput = new WebRtcAudioTrack(context, audioManager,
          audioAttributes, audioTrackErrorCallback, audioTrackStateCallback, useLowLatency);
      return new JavaAudioDeviceModule(context, audioManager, audioInput, audioOutput,
          inputSampleRate, outputSampleRate, useStereoInput, useStereoOutput);
    }
  }

  /* AudioRecord */
  // Audio recording error handler functions.
  public enum AudioRecordStartErrorCode {
    AUDIO_RECORD_START_EXCEPTION,
    AUDIO_RECORD_START_STATE_MISMATCH,
  }

  public static interface AudioRecordErrorCallback {
    void onWebRtcAudioRecordInitError(String errorMessage);
    void onWebRtcAudioRecordStartError(AudioRecordStartErrorCode errorCode, String errorMessage);
    void onWebRtcAudioRecordError(String errorMessage);
  }

  /** Called when audio recording starts and stops. */
  public static interface AudioRecordStateCallback {
    void onWebRtcAudioRecordStart();
    void onWebRtcAudioRecordStop();
  }

  /**
   * Contains audio sample information.
   */
  public static class AudioSamples {
    /** See {@link AudioRecord#getAudioFormat()} */
    private final int audioFormat;
    /** See {@link AudioRecord#getChannelCount()} */
    private final int channelCount;
    /** See {@link AudioRecord#getSampleRate()} */
    private final int sampleRate;

    private final byte[] data;

    public AudioSamples(int audioFormat, int channelCount, int sampleRate, byte[] data) {
      this.audioFormat = audioFormat;
      this.channelCount = channelCount;
      this.sampleRate = sampleRate;
      this.data = data;
    }

    public int getAudioFormat() {
      return audioFormat;
    }

    public int getChannelCount() {
      return channelCount;
    }

    public int getSampleRate() {
      return sampleRate;
    }

    public byte[] getData() {
      return data;
    }
  }

  /** Called when new audio samples are ready. This should only be set for debug purposes */
  public static interface SamplesReadyCallback {
    void onWebRtcAudioRecordSamplesReady(AudioSamples samples);
  }

  /* AudioTrack */
  // Audio playout/track error handler functions.
  public enum AudioTrackStartErrorCode {
    AUDIO_TRACK_START_EXCEPTION,
    AUDIO_TRACK_START_STATE_MISMATCH,
  }

  public static interface AudioTrackErrorCallback {
    void onWebRtcAudioTrackInitError(String errorMessage);
    void onWebRtcAudioTrackStartError(AudioTrackStartErrorCode errorCode, String errorMessage);
    void onWebRtcAudioTrackError(String errorMessage);
  }

  /** Called when audio playout starts and stops. */
  public static interface AudioTrackStateCallback {
    void onWebRtcAudioTrackStart();
    void onWebRtcAudioTrackStop();
  }

  /**
   * Returns true if the device supports built-in HW AEC, and the UUID is approved (some UUIDs can
   * be excluded).
   */
  public static boolean isBuiltInAcousticEchoCancelerSupported() {
    return WebRtcAudioEffects.isAcousticEchoCancelerSupported();
  }

  /**
   * Returns true if the device supports built-in HW NS, and the UUID is approved (some UUIDs can be
   * excluded).
   */
  public static boolean isBuiltInNoiseSuppressorSupported() {
    return WebRtcAudioEffects.isNoiseSuppressorSupported();
  }

  private final Context context;
  private final AudioManager audioManager;
  private final WebRtcAudioRecord audioInput;
  private final WebRtcAudioTrack audioOutput;
  private final int inputSampleRate;
  private final int outputSampleRate;
  private final boolean useStereoInput;
  private final boolean useStereoOutput;

  private final Object nativeLock = new Object();
  private long nativeAudioDeviceModule;

  private JavaAudioDeviceModule(Context context, AudioManager audioManager,
      WebRtcAudioRecord audioInput, WebRtcAudioTrack audioOutput, int inputSampleRate,
      int outputSampleRate, boolean useStereoInput, boolean useStereoOutput) {
    this.context = context;
    this.audioManager = audioManager;
    this.audioInput = audioInput;
    this.audioOutput = audioOutput;
    this.inputSampleRate = inputSampleRate;
    this.outputSampleRate = outputSampleRate;
    this.useStereoInput = useStereoInput;
    this.useStereoOutput = useStereoOutput;
  }

  @Override
  public long getNativeAudioDeviceModulePointer() {
    synchronized (nativeLock) {
      if (nativeAudioDeviceModule == 0) {
        nativeAudioDeviceModule = nativeCreateAudioDeviceModule(context, audioManager, audioInput,
            audioOutput, inputSampleRate, outputSampleRate, useStereoInput, useStereoOutput);
      }
      return nativeAudioDeviceModule;
    }
  }

  @Override
  public void release() {
    synchronized (nativeLock) {
      if (nativeAudioDeviceModule != 0) {
        JniCommon.nativeReleaseRef(nativeAudioDeviceModule);
        nativeAudioDeviceModule = 0;
      }
    }
  }

  @Override
  public void setSpeakerMute(boolean mute) {
    Logging.d(TAG, "setSpeakerMute: " + mute);
    audioOutput.setSpeakerMute(mute);
  }

  @Override
  public void setMicrophoneMute(boolean mute) {
    Logging.d(TAG, "setMicrophoneMute: " + mute);
    audioInput.setMicrophoneMute(mute);
  }

  /**
   * Start to prefer a specific {@link AudioDeviceInfo} device for recording. Typically this should
   * only be used if a client gives an explicit option for choosing a physical device to record
   * from. Otherwise the best-matching device for other parameters will be used. Calling after
   * recording is started may cause a temporary interruption if the audio routing changes.
   */
  @RequiresApi(Build.VERSION_CODES.M)
  public void setPreferredInputDevice(AudioDeviceInfo preferredInputDevice) {
    Logging.d(TAG, "setPreferredInputDevice: " + preferredInputDevice);
    audioInput.setPreferredDevice(preferredInputDevice);
  }

  private static native long nativeCreateAudioDeviceModule(Context context,
      AudioManager audioManager, WebRtcAudioRecord audioInput, WebRtcAudioTrack audioOutput,
      int inputSampleRate, int outputSampleRate, boolean useStereoInput, boolean useStereoOutput);
}