// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module audio.mojom;

import "mojo/public/mojom/base/file.mojom";
import "mojo/public/mojom/base/time.mojom";
import "mojo/public/mojom/base/unguessable_token.mojom";

struct AudioProcessingStats {
  bool typing_noise_detected;

  // (https://crbug.com/657632) Numeric values can't be optional, so add flags
  // for each of them.
  bool has_echo_return_loss;
  double echo_return_loss;

  bool has_echo_return_loss_enhancement;
  double echo_return_loss_enhancement;

  bool has_divergent_filter_fraction;
  double divergent_filter_fraction;

  bool has_delay_median_ms;
  int32 delay_median_ms;

  bool has_delay_standard_deviation_ms;
  int32 delay_standard_deviation_ms;

  bool has_residual_echo_likelihood;
  double residual_echo_likelihood;

  bool has_residual_echo_likelihood_recent_max;
  double residual_echo_likelihood_recent_max;

  bool has_delay_ms;
  int32 delay_ms;
};

enum AutomaticGainControlType {
  kDisabled,
  kDefault,
  kExperimental,
  kHybridExperimental
};

enum EchoCancellationType {
  kDisabled,
  kAec2,
  kAec3,
  kSystemAec
};

enum NoiseSuppressionType {
  kDisabled,
  kDefault,
  kExperimental
};

struct AudioProcessingSettings {
  EchoCancellationType echo_cancellation;
  NoiseSuppressionType noise_suppression;
  AutomaticGainControlType automatic_gain_control;
  bool high_pass_filter;
  bool typing_detection;
  bool stereo_mirroring;
};

// This interface is hosted in the audio service and called from the renderer.
// It is only used when running the audio service out of process.
interface AudioProcessorControls {
  // Request the latest stats from the audio processor. At the farthest level,
  // this is triggered by calls from JavaScript, through some levels of
  // indirection. (See: https://www.w3.org/TR/webrtc-stats/). Since there are no
  // guarantees in the standard about the rate at which stats change, it is
  // reasonable to let multiple user-facing calls result in just one call to
  // this function.
  GetStats() => (AudioProcessingStats stats);

  // Begin dumping echo cancellation data into |file|. AEC dumps can be
  // initiated by the user and then be used to track audio quality issues before
  // and after audio processing.
  StartEchoCancellationDump(mojo_base.mojom.File file);

  // Stop any ongoing dump of echo cancellation data.
  StopEchoCancellationDump();
};

struct AudioProcessingConfig {
  // Used for getting stats and controlling AEC dumps.
  AudioProcessorControls& controls_request;

  // Used for connecting streams to the audio processor.
  mojo_base.mojom.UnguessableToken processing_id;

  // Used for determining which kind of audio processing is enabled.
  AudioProcessingSettings settings;
};