/******************************************************************************
 *
 *  Copyright 2016 The Android Open Source Project
 *  Copyright 2009-2012 Broadcom Corporation
 *
 *  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.
 *
 ******************************************************************************/

#define LOG_TAG "bt_btif_a2dp_source"
#define ATRACE_TAG ATRACE_TAG_AUDIO

#include <base/logging.h>
#include <base/run_loop.h>
#ifndef OS_GENERIC
#include <cutils/trace.h>
#endif
#include <inttypes.h>
#include <limits.h>
#include <string.h>

#include <algorithm>

#include "audio_a2dp_hw/include/audio_a2dp_hw.h"
#include "audio_hal_interface/a2dp_encoding.h"
#include "bta_av_ci.h"
#include "btif_a2dp.h"
#include "btif_a2dp_control.h"
#include "btif_a2dp_source.h"
#include "btif_av.h"
#include "btif_av_co.h"
#include "btif_metrics_logging.h"
#include "btif_util.h"
#include "common/message_loop_thread.h"
#include "common/metrics.h"
#include "common/repeating_timer.h"
#include "common/time_util.h"
#include "osi/include/allocator.h"
#include "osi/include/fixed_queue.h"
#include "osi/include/log.h"
#include "osi/include/osi.h"
#include "osi/include/wakelock.h"
#include "stack/include/acl_api.h"
#include "stack/include/acl_api_types.h"
#include "stack/include/bt_hdr.h"
#include "types/raw_address.h"
#include "uipc.h"

using bluetooth::common::A2dpSessionMetrics;
using bluetooth::common::BluetoothMetricsLogger;
using bluetooth::common::RepeatingTimer;

extern std::unique_ptr<tUIPC_STATE> a2dp_uipc;

/**
 * The typical runlevel of the tx queue size is ~1 buffer
 * but due to link flow control or thread preemption in lower
 * layers we might need to temporarily buffer up data.
 */
#define MAX_OUTPUT_A2DP_FRAME_QUEUE_SZ (MAX_PCM_FRAME_NUM_PER_TICK * 2)

class SchedulingStats {
 public:
  SchedulingStats() { Reset(); }
  void Reset() {
    total_updates = 0;
    last_update_us = 0;
    overdue_scheduling_count = 0;
    total_overdue_scheduling_delta_us = 0;
    max_overdue_scheduling_delta_us = 0;
    premature_scheduling_count = 0;
    total_premature_scheduling_delta_us = 0;
    max_premature_scheduling_delta_us = 0;
    exact_scheduling_count = 0;
    total_scheduling_time_us = 0;
  }

  // Counter for total updates
  size_t total_updates;

  // Last update timestamp (in us)
  uint64_t last_update_us;

  // Counter for overdue scheduling
  size_t overdue_scheduling_count;

  // Accumulated overdue scheduling deviations (in us)
  uint64_t total_overdue_scheduling_delta_us;

  // Max. overdue scheduling delta time (in us)
  uint64_t max_overdue_scheduling_delta_us;

  // Counter for premature scheduling
  size_t premature_scheduling_count;

  // Accumulated premature scheduling deviations (in us)
  uint64_t total_premature_scheduling_delta_us;

  // Max. premature scheduling delta time (in us)
  uint64_t max_premature_scheduling_delta_us;

  // Counter for exact scheduling
  size_t exact_scheduling_count;

  // Accumulated and counted scheduling time (in us)
  uint64_t total_scheduling_time_us;
};

class BtifMediaStats {
 public:
  BtifMediaStats() { Reset(); }
  void Reset() {
    session_start_us = 0;
    session_end_us = 0;
    tx_queue_enqueue_stats.Reset();
    tx_queue_dequeue_stats.Reset();
    tx_queue_total_frames = 0;
    tx_queue_max_frames_per_packet = 0;
    tx_queue_total_queueing_time_us = 0;
    tx_queue_max_queueing_time_us = 0;
    tx_queue_total_readbuf_calls = 0;
    tx_queue_last_readbuf_us = 0;
    tx_queue_total_flushed_messages = 0;
    tx_queue_last_flushed_us = 0;
    tx_queue_total_dropped_messages = 0;
    tx_queue_max_dropped_messages = 0;
    tx_queue_dropouts = 0;
    tx_queue_last_dropouts_us = 0;
    media_read_total_underflow_bytes = 0;
    media_read_total_underflow_count = 0;
    media_read_last_underflow_us = 0;
    codec_index = -1;
  }

  uint64_t session_start_us;
  uint64_t session_end_us;

  SchedulingStats tx_queue_enqueue_stats;
  SchedulingStats tx_queue_dequeue_stats;

  size_t tx_queue_total_frames;
  size_t tx_queue_max_frames_per_packet;

  uint64_t tx_queue_total_queueing_time_us;
  uint64_t tx_queue_max_queueing_time_us;

  size_t tx_queue_total_readbuf_calls;
  uint64_t tx_queue_last_readbuf_us;

  size_t tx_queue_total_flushed_messages;
  uint64_t tx_queue_last_flushed_us;

  size_t tx_queue_total_dropped_messages;
  size_t tx_queue_max_dropped_messages;
  size_t tx_queue_dropouts;
  uint64_t tx_queue_last_dropouts_us;

  size_t media_read_total_underflow_bytes;
  size_t media_read_total_underflow_count;
  uint64_t media_read_last_underflow_us;

  int codec_index = -1;
};

class BtifA2dpSource {
 public:
  enum RunState {
    kStateOff,
    kStateStartingUp,
    kStateRunning,
    kStateShuttingDown
  };

  BtifA2dpSource()
      : tx_audio_queue(nullptr),
        tx_flush(false),
        encoder_interface(nullptr),
        encoder_interval_ms(0),
        state_(kStateOff) {}

  void Reset() {
    fixed_queue_free(tx_audio_queue, nullptr);
    tx_audio_queue = nullptr;
    tx_flush = false;
    media_alarm.CancelAndWait();
    wakelock_release();
    encoder_interface = nullptr;
    encoder_interval_ms = 0;
    stats.Reset();
    accumulated_stats.Reset();
    state_ = kStateOff;
  }

  BtifA2dpSource::RunState State() const { return state_; }
  std::string StateStr() const {
    switch (state_) {
      case kStateOff:
        return "STATE_OFF";
      case kStateStartingUp:
        return "STATE_STARTING_UP";
      case kStateRunning:
        return "STATE_RUNNING";
      case kStateShuttingDown:
        return "STATE_SHUTTING_DOWN";
    }
  }

  void SetState(BtifA2dpSource::RunState state) { state_ = state; }

  fixed_queue_t* tx_audio_queue;
  bool tx_flush; /* Discards any outgoing data when true */
  RepeatingTimer media_alarm;
  const tA2DP_ENCODER_INTERFACE* encoder_interface;
  uint64_t encoder_interval_ms; /* Local copy of the encoder interval */
  BtifMediaStats stats;
  BtifMediaStats accumulated_stats;

 private:
  BtifA2dpSource::RunState state_;
};

static bluetooth::common::MessageLoopThread btif_a2dp_source_thread(
    "bt_a2dp_source_worker_thread");
static BtifA2dpSource btif_a2dp_source_cb;

static uint8_t btif_a2dp_source_dynamic_audio_buffer_size =
    MAX_OUTPUT_A2DP_FRAME_QUEUE_SZ;

static void btif_a2dp_source_init_delayed(void);
static void btif_a2dp_source_startup_delayed(void);
static void btif_a2dp_source_start_session_delayed(
    const RawAddress& peer_address, std::promise<void> start_session_promise);
static void btif_a2dp_source_end_session_delayed(
    const RawAddress& peer_address);
static void btif_a2dp_source_shutdown_delayed(void);
static void btif_a2dp_source_cleanup_delayed(void);
static void btif_a2dp_source_audio_tx_start_event(void);
static void btif_a2dp_source_audio_tx_stop_event(void);
static void btif_a2dp_source_audio_tx_flush_event(void);
// Set up the A2DP Source codec, and prepare the encoder.
// The peer address is |peer_addr|.
// This function should be called prior to starting A2DP streaming.
static void btif_a2dp_source_setup_codec(const RawAddress& peer_addr);
static void btif_a2dp_source_setup_codec_delayed(
    const RawAddress& peer_address);
static void btif_a2dp_source_cleanup_codec();
static void btif_a2dp_source_cleanup_codec_delayed();
static void btif_a2dp_source_encoder_user_config_update_event(
    const RawAddress& peer_address,
    const std::vector<btav_a2dp_codec_config_t>& codec_user_preferences,
    std::promise<void> peer_ready_promise);
static void btif_a2dp_source_audio_feeding_update_event(
    const btav_a2dp_codec_config_t& codec_audio_config);
static bool btif_a2dp_source_audio_tx_flush_req(void);
static void btif_a2dp_source_audio_handle_timer(void);
static uint32_t btif_a2dp_source_read_callback(uint8_t* p_buf, uint32_t len);
static bool btif_a2dp_source_enqueue_callback(BT_HDR* p_buf, size_t frames_n,
                                              uint32_t bytes_read);
static void log_tstamps_us(const char* comment, uint64_t timestamp_us);
static void update_scheduling_stats(SchedulingStats* stats, uint64_t now_us,
                                    uint64_t expected_delta);
// Update the A2DP Source related metrics.
// This function should be called before collecting the metrics.
static void btif_a2dp_source_update_metrics(void);
static void btm_read_rssi_cb(void* data);
static void btm_read_failed_contact_counter_cb(void* data);
static void btm_read_tx_power_cb(void* data);

void btif_a2dp_source_accumulate_scheduling_stats(SchedulingStats* src,
                                                  SchedulingStats* dst) {
  dst->total_updates += src->total_updates;
  dst->last_update_us = src->last_update_us;
  dst->overdue_scheduling_count += src->overdue_scheduling_count;
  dst->total_overdue_scheduling_delta_us +=
      src->total_overdue_scheduling_delta_us;
  dst->max_overdue_scheduling_delta_us =
      std::max(dst->max_overdue_scheduling_delta_us,
               src->max_overdue_scheduling_delta_us);
  dst->premature_scheduling_count += src->premature_scheduling_count;
  dst->total_premature_scheduling_delta_us +=
      src->total_premature_scheduling_delta_us;
  dst->max_premature_scheduling_delta_us =
      std::max(dst->max_premature_scheduling_delta_us,
               src->max_premature_scheduling_delta_us);
  dst->exact_scheduling_count += src->exact_scheduling_count;
  dst->total_scheduling_time_us += src->total_scheduling_time_us;
}

void btif_a2dp_source_accumulate_stats(BtifMediaStats* src,
                                       BtifMediaStats* dst) {
  dst->tx_queue_total_frames += src->tx_queue_total_frames;
  dst->tx_queue_max_frames_per_packet = std::max(
      dst->tx_queue_max_frames_per_packet, src->tx_queue_max_frames_per_packet);
  dst->tx_queue_total_queueing_time_us += src->tx_queue_total_queueing_time_us;
  dst->tx_queue_max_queueing_time_us = std::max(
      dst->tx_queue_max_queueing_time_us, src->tx_queue_max_queueing_time_us);
  dst->tx_queue_total_readbuf_calls += src->tx_queue_total_readbuf_calls;
  dst->tx_queue_last_readbuf_us = src->tx_queue_last_readbuf_us;
  dst->tx_queue_total_flushed_messages += src->tx_queue_total_flushed_messages;
  dst->tx_queue_last_flushed_us = src->tx_queue_last_flushed_us;
  dst->tx_queue_total_dropped_messages += src->tx_queue_total_dropped_messages;
  dst->tx_queue_max_dropped_messages = std::max(
      dst->tx_queue_max_dropped_messages, src->tx_queue_max_dropped_messages);
  dst->tx_queue_dropouts += src->tx_queue_dropouts;
  dst->tx_queue_last_dropouts_us = src->tx_queue_last_dropouts_us;
  dst->media_read_total_underflow_bytes +=
      src->media_read_total_underflow_bytes;
  dst->media_read_total_underflow_count +=
      src->media_read_total_underflow_count;
  dst->media_read_last_underflow_us = src->media_read_last_underflow_us;
  if (dst->codec_index < 0) dst->codec_index = src->codec_index;
  btif_a2dp_source_accumulate_scheduling_stats(&src->tx_queue_enqueue_stats,
                                               &dst->tx_queue_enqueue_stats);
  btif_a2dp_source_accumulate_scheduling_stats(&src->tx_queue_dequeue_stats,
                                               &dst->tx_queue_dequeue_stats);
  src->Reset();
}

bool btif_a2dp_source_init(void) {
  LOG_INFO("%s", __func__);

  // Start A2DP Source media task
  btif_a2dp_source_thread.StartUp();
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_init_delayed));
  return true;
}

static void btif_a2dp_source_init_delayed(void) {
  LOG_INFO("%s", __func__);
  // Nothing to do
}

bool btif_a2dp_source_startup(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  if (btif_a2dp_source_cb.State() != BtifA2dpSource::kStateOff) {
    LOG_ERROR("%s: A2DP Source media task already running", __func__);
    return false;
  }

  btif_a2dp_source_cb.Reset();
  btif_a2dp_source_cb.SetState(BtifA2dpSource::kStateStartingUp);
  btif_a2dp_source_cb.tx_audio_queue = fixed_queue_new(SIZE_MAX);

  // Schedule the rest of the operations
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_startup_delayed));

  return true;
}

static void btif_a2dp_source_startup_delayed() {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (!btif_a2dp_source_thread.EnableRealTimeScheduling()) {
#if defined(OS_ANDROID)
    LOG(FATAL) << __func__ << ": unable to enable real time scheduling";
#endif
  }
  if (!bluetooth::audio::a2dp::init(&btif_a2dp_source_thread)) {
    if (btif_av_is_a2dp_offload_enabled()) {
      // TODO: BluetoothA2dp@1.0 is deprecated
      LOG(WARNING) << __func__ << ": Using BluetoothA2dp HAL";
    } else {
      LOG(WARNING) << __func__ << ": Using legacy HAL";
      btif_a2dp_control_init();
    }
  }
  btif_a2dp_source_cb.SetState(BtifA2dpSource::kStateRunning);
}

bool btif_a2dp_source_start_session(const RawAddress& peer_address,
                                    std::promise<void> peer_ready_promise) {
  LOG(INFO) << __func__ << ": peer_address=" << peer_address
            << " state=" << btif_a2dp_source_cb.StateStr();
  btif_a2dp_source_setup_codec(peer_address);
  if (btif_a2dp_source_thread.DoInThread(
          FROM_HERE,
          base::BindOnce(&btif_a2dp_source_start_session_delayed, peer_address,
                         std::move(peer_ready_promise)))) {
    return true;
  } else {
    // cannot set promise but triggers crash
    LOG(FATAL) << __func__ << ": peer_address=" << peer_address
               << " state=" << btif_a2dp_source_cb.StateStr()
               << " fails to context switch";
    return false;
  }
}

static void btif_a2dp_source_start_session_delayed(
    const RawAddress& peer_address, std::promise<void> peer_ready_promise) {
  LOG(INFO) << __func__ << ": peer_address=" << peer_address
            << " state=" << btif_a2dp_source_cb.StateStr();
  if (btif_a2dp_source_cb.State() != BtifA2dpSource::kStateRunning) {
    LOG(ERROR) << __func__ << ": A2DP Source media task is not running";
    peer_ready_promise.set_value();
    return;
  }
  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bluetooth::audio::a2dp::start_session();
    bluetooth::audio::a2dp::set_remote_delay(btif_av_get_audio_delay());
    BluetoothMetricsLogger::GetInstance()->LogBluetoothSessionStart(
        bluetooth::common::CONNECTION_TECHNOLOGY_TYPE_BREDR, 0);
  } else {
    BluetoothMetricsLogger::GetInstance()->LogBluetoothSessionStart(
        bluetooth::common::CONNECTION_TECHNOLOGY_TYPE_BREDR, 0);
  }
  peer_ready_promise.set_value();
}

bool btif_a2dp_source_restart_session(const RawAddress& old_peer_address,
                                      const RawAddress& new_peer_address,
                                      std::promise<void> peer_ready_promise) {
  bool is_streaming = btif_a2dp_source_cb.media_alarm.IsScheduled();
  LOG(INFO) << __func__ << ": old_peer_address=" << old_peer_address
            << " new_peer_address=" << new_peer_address
            << " is_streaming=" << logbool(is_streaming)
            << " state=" << btif_a2dp_source_cb.StateStr();

  CHECK(!new_peer_address.IsEmpty());

  // Must stop first the audio streaming
  if (is_streaming) {
    btif_a2dp_source_stop_audio_req();
  }

  // If the old active peer was valid, end the old session.
  // Otherwise, time to startup the A2DP Source processing.
  if (!old_peer_address.IsEmpty()) {
    btif_a2dp_source_end_session(old_peer_address);
  } else {
    btif_a2dp_source_startup();
  }

  // Start the session.
  btif_a2dp_source_start_session(new_peer_address,
                                 std::move(peer_ready_promise));
  // If audio was streaming before, DON'T start audio streaming, but leave the
  // control to the audio HAL.
  return true;
}

bool btif_a2dp_source_end_session(const RawAddress& peer_address) {
  LOG_INFO("%s: peer_address=%s state=%s", __func__,
           peer_address.ToString().c_str(),
           btif_a2dp_source_cb.StateStr().c_str());
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE,
      base::Bind(&btif_a2dp_source_end_session_delayed, peer_address));
  btif_a2dp_source_cleanup_codec();
  return true;
}

static void btif_a2dp_source_end_session_delayed(
    const RawAddress& peer_address) {
  LOG_INFO("%s: peer_address=%s state=%s", __func__,
           peer_address.ToString().c_str(),
           btif_a2dp_source_cb.StateStr().c_str());
  if ((btif_a2dp_source_cb.State() == BtifA2dpSource::kStateRunning) ||
      (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateShuttingDown)) {
    btif_av_stream_stop(peer_address);
  } else {
    LOG_ERROR("%s: A2DP Source media task is not running", __func__);
  }
  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bluetooth::audio::a2dp::end_session();
    BluetoothMetricsLogger::GetInstance()->LogBluetoothSessionEnd(
        bluetooth::common::DISCONNECT_REASON_UNKNOWN, 0);
  } else {
    BluetoothMetricsLogger::GetInstance()->LogBluetoothSessionEnd(
        bluetooth::common::DISCONNECT_REASON_UNKNOWN, 0);
  }
}

void btif_a2dp_source_shutdown(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  if ((btif_a2dp_source_cb.State() == BtifA2dpSource::kStateOff) ||
      (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateShuttingDown)) {
    return;
  }

  /* Make sure no channels are restarted while shutting down */
  btif_a2dp_source_cb.SetState(BtifA2dpSource::kStateShuttingDown);

  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_shutdown_delayed));
}

static void btif_a2dp_source_shutdown_delayed(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  // Stop the timer
  btif_a2dp_source_cb.media_alarm.CancelAndWait();
  wakelock_release();

  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bluetooth::audio::a2dp::cleanup();
  } else {
    btif_a2dp_control_cleanup();
  }
  fixed_queue_free(btif_a2dp_source_cb.tx_audio_queue, nullptr);
  btif_a2dp_source_cb.tx_audio_queue = nullptr;

  btif_a2dp_source_cb.SetState(BtifA2dpSource::kStateOff);
}

void btif_a2dp_source_cleanup(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  // Make sure the source is shutdown
  btif_a2dp_source_shutdown();

  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_cleanup_delayed));

  // Exit the thread
  btif_a2dp_source_thread.ShutDown();
}

static void btif_a2dp_source_cleanup_delayed(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  // Nothing to do
}

bool btif_a2dp_source_media_task_is_running(void) {
  return (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateRunning);
}

bool btif_a2dp_source_media_task_is_shutting_down(void) {
  return (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateShuttingDown);
}

bool btif_a2dp_source_is_streaming(void) {
  return btif_a2dp_source_cb.media_alarm.IsScheduled();
}

static void btif_a2dp_source_setup_codec(const RawAddress& peer_address) {
  LOG_INFO("%s: peer_address=%s state=%s", __func__,
           peer_address.ToString().c_str(),
           btif_a2dp_source_cb.StateStr().c_str());

  // Check to make sure the platform has 8 bits/byte since
  // we're using that in frame size calculations now.
  CHECK(CHAR_BIT == 8);

  btif_a2dp_source_audio_tx_flush_req();
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE,
      base::Bind(&btif_a2dp_source_setup_codec_delayed, peer_address));
}

static void btif_a2dp_source_setup_codec_delayed(
    const RawAddress& peer_address) {
  LOG_INFO("%s: peer_address=%s state=%s", __func__,
           peer_address.ToString().c_str(),
           btif_a2dp_source_cb.StateStr().c_str());

  tA2DP_ENCODER_INIT_PEER_PARAMS peer_params;
  bta_av_co_get_peer_params(peer_address, &peer_params);

  if (!bta_av_co_set_active_peer(peer_address)) {
    LOG_ERROR("%s: Cannot stream audio: cannot set active peer to %s", __func__,
              peer_address.ToString().c_str());
    return;
  }
  btif_a2dp_source_cb.encoder_interface = bta_av_co_get_encoder_interface();
  if (btif_a2dp_source_cb.encoder_interface == nullptr) {
    LOG_ERROR("%s: Cannot stream audio: no source encoder interface", __func__);
    return;
  }

  A2dpCodecConfig* a2dp_codec_config = bta_av_get_a2dp_current_codec();
  if (a2dp_codec_config == nullptr) {
    LOG_ERROR("%s: Cannot stream audio: current codec is not set", __func__);
    return;
  }

  btif_a2dp_source_cb.encoder_interface->encoder_init(
      &peer_params, a2dp_codec_config, btif_a2dp_source_read_callback,
      btif_a2dp_source_enqueue_callback);

  // Save a local copy of the encoder_interval_ms
  btif_a2dp_source_cb.encoder_interval_ms =
      btif_a2dp_source_cb.encoder_interface->get_encoder_interval_ms();

  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bluetooth::audio::a2dp::setup_codec();
  }
}

static void btif_a2dp_source_cleanup_codec() {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (btif_a2dp_source_is_streaming()) {
    // Must stop media task first before cleaning up the encoder
    btif_a2dp_source_stop_audio_req();
  }
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_cleanup_codec_delayed));
}

static void btif_a2dp_source_cleanup_codec_delayed() {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (btif_a2dp_source_cb.encoder_interface != nullptr) {
    btif_a2dp_source_cb.encoder_interface->encoder_cleanup();
    btif_a2dp_source_cb.encoder_interface = nullptr;
  }
}

void btif_a2dp_source_start_audio_req(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_audio_tx_start_event));
}

void btif_a2dp_source_stop_audio_req(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_audio_tx_stop_event));
}

void btif_a2dp_source_encoder_user_config_update_req(
    const RawAddress& peer_address,
    const std::vector<btav_a2dp_codec_config_t>& codec_user_preferences,
    std::promise<void> peer_ready_promise) {
  LOG(INFO) << __func__ << ": peer_address=" << peer_address
            << " state=" << btif_a2dp_source_cb.StateStr() << " "
            << codec_user_preferences.size() << " codec_preference(s)";
  if (!btif_a2dp_source_thread.DoInThread(
          FROM_HERE,
          base::BindOnce(&btif_a2dp_source_encoder_user_config_update_event,
                         peer_address, codec_user_preferences,
                         std::move(peer_ready_promise)))) {
    // cannot set promise but triggers crash
    LOG(FATAL) << __func__ << ": peer_address=" << peer_address
               << " state=" << btif_a2dp_source_cb.StateStr()
               << " fails to context switch";
  }
}

static void btif_a2dp_source_encoder_user_config_update_event(
    const RawAddress& peer_address,
    const std::vector<btav_a2dp_codec_config_t>& codec_user_preferences,
    std::promise<void> peer_ready_promise) {
  bool restart_output = false;
  bool success = false;
  for (auto codec_user_config : codec_user_preferences) {
    success = bta_av_co_set_codec_user_config(peer_address, codec_user_config,
                                              &restart_output);
    if (success) {
      LOG(INFO) << __func__ << ": peer_address=" << peer_address
                << " state=" << btif_a2dp_source_cb.StateStr()
                << " codec_preference={" << codec_user_config.ToString()
                << "} restart_output=" << (restart_output ? "true" : "false");
      break;
    }
  }
  if (success && restart_output) {
    // Codec reconfiguration is in progress, and it is safe to unlock since
    // remaining tasks like starting audio session and reporting new codec
    // will be handled by BTA_AV_RECONFIG_EVT later.
    peer_ready_promise.set_value();
    return;
  }
  if (!success) {
    LOG(ERROR) << __func__ << ": cannot update codec user configuration(s)";
  }
  if (!peer_address.IsEmpty() && peer_address == btif_av_source_active_peer()) {
    // No more actions needed with remote, and if succeed, user had changed the
    // config like the bits per sample only. Let's resume the session now.
    btif_a2dp_source_start_session(peer_address, std::move(peer_ready_promise));
  } else {
    // Unlock for non-active peer
    peer_ready_promise.set_value();
  }
}

void btif_a2dp_source_feeding_update_req(
    const btav_a2dp_codec_config_t& codec_audio_config) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_audio_feeding_update_event,
                            codec_audio_config));
}

static void btif_a2dp_source_audio_feeding_update_event(
    const btav_a2dp_codec_config_t& codec_audio_config) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (!bta_av_co_set_codec_audio_config(codec_audio_config)) {
    LOG_ERROR("%s: cannot update codec audio feeding parameters", __func__);
  }
}

void btif_a2dp_source_on_idle(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateOff) return;

  /* Make sure media task is stopped */
  btif_a2dp_source_stop_audio_req();
}

void btif_a2dp_source_on_stopped(tBTA_AV_SUSPEND* p_av_suspend) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  if (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateOff) return;

  // allow using this API for other (acknowledgement and stopping media task)
  // than suspend
  if (p_av_suspend != nullptr && p_av_suspend->status != BTA_AV_SUCCESS) {
    LOG_ERROR("%s: A2DP stop failed: status=%d, initiator=%s", __func__,
              p_av_suspend->status,
              (p_av_suspend->initiator ? "true" : "false"));
    if (p_av_suspend->initiator) {
      if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
        bluetooth::audio::a2dp::ack_stream_suspended(A2DP_CTRL_ACK_FAILURE);
      } else {
        btif_a2dp_command_ack(A2DP_CTRL_ACK_FAILURE);
      }
    }
  } else if (btif_av_is_a2dp_offload_running()) {
    bluetooth::audio::a2dp::ack_stream_suspended(A2DP_CTRL_ACK_SUCCESS);
    return;
  }

  // ensure tx frames are immediately suspended
  btif_a2dp_source_cb.tx_flush = true;
  // ensure tx frames are immediately flushed
  btif_a2dp_source_audio_tx_flush_req();

  // request to stop media task
  btif_a2dp_source_stop_audio_req();

  // once software stream is fully stopped we will ack back
}

void btif_a2dp_source_on_suspended(tBTA_AV_SUSPEND* p_av_suspend) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  if (btif_a2dp_source_cb.State() == BtifA2dpSource::kStateOff) return;

  CHECK(p_av_suspend != nullptr) << "Suspend result could not be nullptr";

  // check for status failures
  if (p_av_suspend->status != BTA_AV_SUCCESS) {
    LOG_WARN("%s: A2DP suspend failed: status=%d, initiator=%s", __func__,
             p_av_suspend->status,
             (p_av_suspend->initiator ? "true" : "false"));
    if (p_av_suspend->initiator) {
      if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
        bluetooth::audio::a2dp::ack_stream_suspended(A2DP_CTRL_ACK_FAILURE);
      } else {
        btif_a2dp_command_ack(A2DP_CTRL_ACK_FAILURE);
      }
    }
  } else if (btif_av_is_a2dp_offload_running()) {
    bluetooth::audio::a2dp::ack_stream_suspended(A2DP_CTRL_ACK_SUCCESS);
    return;
  }

  // ensure tx frames are immediately suspended
  btif_a2dp_source_cb.tx_flush = true;

  // stop timer tick
  btif_a2dp_source_stop_audio_req();

  // once software stream is fully stopped we will ack back
}

/* when true media task discards any tx frames */
void btif_a2dp_source_set_tx_flush(bool enable) {
  LOG_INFO("%s: enable=%s state=%s", __func__, (enable) ? "true" : "false",
           btif_a2dp_source_cb.StateStr().c_str());
  btif_a2dp_source_cb.tx_flush = enable;
}

static void btif_a2dp_source_audio_tx_start_event(void) {
  LOG_INFO(
      "%s: media_alarm is %s, streaming %s state=%s", __func__,
      btif_a2dp_source_cb.media_alarm.IsScheduled() ? "running" : "stopped",
      btif_a2dp_source_is_streaming() ? "true" : "false",
      btif_a2dp_source_cb.StateStr().c_str());

  if (btif_av_is_a2dp_offload_running()) return;

  /* Reset the media feeding state */
  CHECK(btif_a2dp_source_cb.encoder_interface != nullptr);
  btif_a2dp_source_cb.encoder_interface->feeding_reset();

  APPL_TRACE_EVENT(
      "%s: starting timer %" PRIu64 " ms", __func__,
      btif_a2dp_source_cb.encoder_interface->get_encoder_interval_ms());

  /* audio engine starting, reset tx suspended flag */
  btif_a2dp_source_cb.tx_flush = false;

  wakelock_acquire();
  btif_a2dp_source_cb.media_alarm.SchedulePeriodic(
      btif_a2dp_source_thread.GetWeakPtr(), FROM_HERE,
      base::Bind(&btif_a2dp_source_audio_handle_timer),
      base::TimeDelta::FromMilliseconds(
          btif_a2dp_source_cb.encoder_interface->get_encoder_interval_ms()));

  btif_a2dp_source_cb.stats.Reset();
  // Assign session_start_us to 1 when
  // bluetooth::common::time_get_os_boottime_us() is 0 to indicate
  // btif_a2dp_source_start_audio_req() has been called
  btif_a2dp_source_cb.stats.session_start_us =
      bluetooth::common::time_get_os_boottime_us();
  if (btif_a2dp_source_cb.stats.session_start_us == 0) {
    btif_a2dp_source_cb.stats.session_start_us = 1;
  }
  btif_a2dp_source_cb.stats.session_end_us = 0;
  A2dpCodecConfig* codec_config = bta_av_get_a2dp_current_codec();
  if (codec_config != nullptr) {
    btif_a2dp_source_cb.stats.codec_index = codec_config->codecIndex();
  }
}

static void btif_a2dp_source_audio_tx_stop_event(void) {
  LOG_INFO(
      "%s: media_alarm is %s, streaming %s state=%s", __func__,
      btif_a2dp_source_cb.media_alarm.IsScheduled() ? "running" : "stopped",
      btif_a2dp_source_is_streaming() ? "true" : "false",
      btif_a2dp_source_cb.StateStr().c_str());

  if (btif_av_is_a2dp_offload_running()) return;

  btif_a2dp_source_cb.stats.session_end_us =
      bluetooth::common::time_get_os_boottime_us();
  btif_a2dp_source_update_metrics();
  btif_a2dp_source_accumulate_stats(&btif_a2dp_source_cb.stats,
                                    &btif_a2dp_source_cb.accumulated_stats);

  uint8_t p_buf[AUDIO_STREAM_OUTPUT_BUFFER_SZ * 2];

  // Keep track of audio data still left in the pipe
  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    btif_a2dp_control_log_bytes_read(
        bluetooth::audio::a2dp::read(p_buf, sizeof(p_buf)));
  } else if (a2dp_uipc != nullptr) {
    btif_a2dp_control_log_bytes_read(
        UIPC_Read(*a2dp_uipc, UIPC_CH_ID_AV_AUDIO, p_buf, sizeof(p_buf)));
  }

  /* Stop the timer first */
  btif_a2dp_source_cb.media_alarm.CancelAndWait();
  wakelock_release();

  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bluetooth::audio::a2dp::ack_stream_suspended(A2DP_CTRL_ACK_SUCCESS);
  } else if (a2dp_uipc != nullptr) {
    UIPC_Close(*a2dp_uipc, UIPC_CH_ID_AV_AUDIO);

    /*
     * Try to send acknowledgement once the media stream is
     * stopped. This will make sure that the A2DP HAL layer is
     * un-blocked on wait for acknowledgment for the sent command.
     * This resolves a corner cases AVDTP SUSPEND collision
     * when the DUT and the remote device issue SUSPEND simultaneously
     * and due to the processing of the SUSPEND request from the remote,
     * the media path is torn down. If the A2DP HAL happens to wait
     * for ACK for the initiated SUSPEND, it would never receive it casuing
     * a block/wait. Due to this acknowledgement, the A2DP HAL is guranteed
     * to get the ACK for any pending command in such cases.
     */

    btif_a2dp_command_ack(A2DP_CTRL_ACK_SUCCESS);
  }

  /* audio engine stopped, reset tx suspended flag */
  btif_a2dp_source_cb.tx_flush = false;

  /* Reset the media feeding state */
  if (btif_a2dp_source_cb.encoder_interface != nullptr)
    btif_a2dp_source_cb.encoder_interface->feeding_reset();
}

static void btif_a2dp_source_audio_handle_timer(void) {
  if (btif_av_is_a2dp_offload_running()) return;

  uint64_t timestamp_us = bluetooth::common::time_get_os_boottime_us();
  log_tstamps_us("A2DP Source tx timer", timestamp_us);

  if (!btif_a2dp_source_cb.media_alarm.IsScheduled()) {
    LOG_ERROR("%s: ERROR Media task Scheduled after Suspend", __func__);
    return;
  }
  CHECK(btif_a2dp_source_cb.encoder_interface != nullptr);
  size_t transmit_queue_length =
      fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue);
#ifndef OS_GENERIC
  ATRACE_INT("btif TX queue", transmit_queue_length);
#endif
  if (btif_a2dp_source_cb.encoder_interface->set_transmit_queue_length !=
      nullptr) {
    btif_a2dp_source_cb.encoder_interface->set_transmit_queue_length(
        transmit_queue_length);
  }
  btif_a2dp_source_cb.encoder_interface->send_frames(timestamp_us);
  bta_av_ci_src_data_ready(BTA_AV_CHNL_AUDIO);
  update_scheduling_stats(&btif_a2dp_source_cb.stats.tx_queue_enqueue_stats,
                          timestamp_us,
                          btif_a2dp_source_cb.encoder_interval_ms * 1000);
}

static uint32_t btif_a2dp_source_read_callback(uint8_t* p_buf, uint32_t len) {
  uint32_t bytes_read = 0;

  if (bluetooth::audio::a2dp::is_hal_2_0_enabled()) {
    bytes_read = bluetooth::audio::a2dp::read(p_buf, len);
  } else if (a2dp_uipc != nullptr) {
    bytes_read = UIPC_Read(*a2dp_uipc, UIPC_CH_ID_AV_AUDIO, p_buf, len);
  }

  if (bytes_read < len) {
    LOG_WARN("%s: UNDERFLOW: ONLY READ %d BYTES OUT OF %d", __func__,
             bytes_read, len);
    btif_a2dp_source_cb.stats.media_read_total_underflow_bytes +=
        (len - bytes_read);
    btif_a2dp_source_cb.stats.media_read_total_underflow_count++;
    btif_a2dp_source_cb.stats.media_read_last_underflow_us =
        bluetooth::common::time_get_os_boottime_us();
    log_a2dp_audio_underrun_event(btif_av_source_active_peer(),
                                  btif_a2dp_source_cb.encoder_interval_ms,
                                  len - bytes_read);
  }

  return bytes_read;
}

static bool btif_a2dp_source_enqueue_callback(BT_HDR* p_buf, size_t frames_n,
                                              uint32_t bytes_read) {
  uint64_t now_us = bluetooth::common::time_get_os_boottime_us();
  btif_a2dp_control_log_bytes_read(bytes_read);

  /* Check if timer was stopped (media task stopped) */
  if (!btif_a2dp_source_cb.media_alarm.IsScheduled()) {
    osi_free(p_buf);
    return false;
  }

  /* Check if the transmission queue has been flushed */
  if (btif_a2dp_source_cb.tx_flush) {
    LOG_VERBOSE("%s: tx suspended, discarded frame", __func__);

    btif_a2dp_source_cb.stats.tx_queue_total_flushed_messages +=
        fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue);
    btif_a2dp_source_cb.stats.tx_queue_last_flushed_us = now_us;
    fixed_queue_flush(btif_a2dp_source_cb.tx_audio_queue, osi_free);

    osi_free(p_buf);
    return false;
  }

  // Check for TX queue overflow
  // TODO: Using frames_n here is probably wrong: should be "+ 1" instead.
  if (fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue) + frames_n >
      btif_a2dp_source_dynamic_audio_buffer_size) {
    LOG_WARN("%s: TX queue buffer size now=%u adding=%u max=%d", __func__,
             (uint32_t)fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue),
             (uint32_t)frames_n, btif_a2dp_source_dynamic_audio_buffer_size);
    // Keep track of drop-outs
    btif_a2dp_source_cb.stats.tx_queue_dropouts++;
    btif_a2dp_source_cb.stats.tx_queue_last_dropouts_us = now_us;

    // Flush all queued buffers
    size_t drop_n = fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue);
    btif_a2dp_source_cb.stats.tx_queue_max_dropped_messages = std::max(
        drop_n, btif_a2dp_source_cb.stats.tx_queue_max_dropped_messages);
    int num_dropped_encoded_bytes = 0;
    int num_dropped_encoded_frames = 0;
    while (fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue)) {
      btif_a2dp_source_cb.stats.tx_queue_total_dropped_messages++;
      void* p_data =
          fixed_queue_try_dequeue(btif_a2dp_source_cb.tx_audio_queue);
      if (p_data != nullptr) {
        auto p_dropped_buf = static_cast<BT_HDR*>(p_data);
        num_dropped_encoded_bytes += p_dropped_buf->len;
        num_dropped_encoded_frames += p_dropped_buf->layer_specific;
        osi_free(p_data);
      }
    }
    log_a2dp_audio_overrun_event(btif_av_source_active_peer(), drop_n,
                                 btif_a2dp_source_cb.encoder_interval_ms,
                                 num_dropped_encoded_frames,
                                 num_dropped_encoded_bytes);

    // Request additional debug info if we had to flush buffers
    RawAddress peer_bda = btif_av_source_active_peer();
    tBTM_STATUS status = BTM_ReadRSSI(peer_bda, btm_read_rssi_cb);
    if (status != BTM_CMD_STARTED) {
      LOG_WARN("%s: Cannot read RSSI: status %d", __func__, status);
    }
    status = BTM_ReadFailedContactCounter(peer_bda,
                                          btm_read_failed_contact_counter_cb);
    if (status != BTM_CMD_STARTED) {
      LOG_WARN("%s: Cannot read Failed Contact Counter: status %d", __func__,
               status);
    }
    status =
        BTM_ReadTxPower(peer_bda, BT_TRANSPORT_BR_EDR, btm_read_tx_power_cb);
    if (status != BTM_CMD_STARTED) {
      LOG_WARN("%s: Cannot read Tx Power: status %d", __func__, status);
    }
  }

  /* Update the statistics */
  btif_a2dp_source_cb.stats.tx_queue_total_frames += frames_n;
  btif_a2dp_source_cb.stats.tx_queue_max_frames_per_packet = std::max(
      frames_n, btif_a2dp_source_cb.stats.tx_queue_max_frames_per_packet);
  CHECK(btif_a2dp_source_cb.encoder_interface != nullptr);

  fixed_queue_enqueue(btif_a2dp_source_cb.tx_audio_queue, p_buf);

  return true;
}

static void btif_a2dp_source_audio_tx_flush_event(void) {
  /* Flush all enqueued audio buffers (encoded) */
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());
  if (btif_av_is_a2dp_offload_running()) return;

  if (btif_a2dp_source_cb.encoder_interface != nullptr)
    btif_a2dp_source_cb.encoder_interface->feeding_flush();

  btif_a2dp_source_cb.stats.tx_queue_total_flushed_messages +=
      fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue);
  btif_a2dp_source_cb.stats.tx_queue_last_flushed_us =
      bluetooth::common::time_get_os_boottime_us();
  fixed_queue_flush(btif_a2dp_source_cb.tx_audio_queue, osi_free);

  if (!bluetooth::audio::a2dp::is_hal_2_0_enabled() && a2dp_uipc != nullptr) {
    UIPC_Ioctl(*a2dp_uipc, UIPC_CH_ID_AV_AUDIO, UIPC_REQ_RX_FLUSH, nullptr);
  }
}

static bool btif_a2dp_source_audio_tx_flush_req(void) {
  LOG_INFO("%s: state=%s", __func__, btif_a2dp_source_cb.StateStr().c_str());

  btif_a2dp_source_thread.DoInThread(
      FROM_HERE, base::Bind(&btif_a2dp_source_audio_tx_flush_event));
  return true;
}

BT_HDR* btif_a2dp_source_audio_readbuf(void) {
  uint64_t now_us = bluetooth::common::time_get_os_boottime_us();
  BT_HDR* p_buf =
      (BT_HDR*)fixed_queue_try_dequeue(btif_a2dp_source_cb.tx_audio_queue);

  btif_a2dp_source_cb.stats.tx_queue_total_readbuf_calls++;
  btif_a2dp_source_cb.stats.tx_queue_last_readbuf_us = now_us;
  if (p_buf != nullptr) {
    // Update the statistics
    update_scheduling_stats(&btif_a2dp_source_cb.stats.tx_queue_dequeue_stats,
                            now_us,
                            btif_a2dp_source_cb.encoder_interval_ms * 1000);
  }

  return p_buf;
}

static void log_tstamps_us(const char* comment, uint64_t timestamp_us) {
  static uint64_t prev_us = 0;
  APPL_TRACE_DEBUG("%s: [%s] ts %08" PRIu64 ", diff : %08" PRIu64
                   ", queue sz %zu",
                   __func__, comment, timestamp_us, timestamp_us - prev_us,
                   fixed_queue_length(btif_a2dp_source_cb.tx_audio_queue));
  prev_us = timestamp_us;
}

static void update_scheduling_stats(SchedulingStats* stats, uint64_t now_us,
                                    uint64_t expected_delta) {
  uint64_t last_us = stats->last_update_us;

  stats->total_updates++;
  stats->last_update_us = now_us;

  if (last_us == 0) return;  // First update: expected delta doesn't apply

  uint64_t deadline_us = last_us + expected_delta;
  if (deadline_us < now_us) {
    // Overdue scheduling
    uint64_t delta_us = now_us - deadline_us;
    // Ignore extreme outliers
    if (delta_us < 10 * expected_delta) {
      stats->max_overdue_scheduling_delta_us =
          std::max(delta_us, stats->max_overdue_scheduling_delta_us);
      stats->total_overdue_scheduling_delta_us += delta_us;
      stats->overdue_scheduling_count++;
      stats->total_scheduling_time_us += now_us - last_us;
    }
  } else if (deadline_us > now_us) {
    // Premature scheduling
    uint64_t delta_us = deadline_us - now_us;
    // Ignore extreme outliers
    if (delta_us < 10 * expected_delta) {
      stats->max_premature_scheduling_delta_us =
          std::max(delta_us, stats->max_premature_scheduling_delta_us);
      stats->total_premature_scheduling_delta_us += delta_us;
      stats->premature_scheduling_count++;
      stats->total_scheduling_time_us += now_us - last_us;
    }
  } else {
    // On-time scheduling
    stats->exact_scheduling_count++;
    stats->total_scheduling_time_us += now_us - last_us;
  }
}

void btif_a2dp_source_debug_dump(int fd) {
  btif_a2dp_source_accumulate_stats(&btif_a2dp_source_cb.stats,
                                    &btif_a2dp_source_cb.accumulated_stats);
  uint64_t now_us = bluetooth::common::time_get_os_boottime_us();
  BtifMediaStats* accumulated_stats = &btif_a2dp_source_cb.accumulated_stats;
  SchedulingStats* enqueue_stats = &accumulated_stats->tx_queue_enqueue_stats;
  SchedulingStats* dequeue_stats = &accumulated_stats->tx_queue_dequeue_stats;
  size_t ave_size;
  uint64_t ave_time_us;

  dprintf(fd, "\nA2DP State:\n");
  dprintf(fd, "  TxQueue:\n");

  dprintf(fd,
          "  Counts (enqueue/dequeue/readbuf)                        : %zu / "
          "%zu / %zu\n",
          enqueue_stats->total_updates, dequeue_stats->total_updates,
          accumulated_stats->tx_queue_total_readbuf_calls);

  dprintf(
      fd,
      "  Last update time ago in ms (enqueue/dequeue/readbuf)    : %llu / %llu "
      "/ %llu\n",
      (enqueue_stats->last_update_us > 0)
          ? (unsigned long long)(now_us - enqueue_stats->last_update_us) / 1000
          : 0,
      (dequeue_stats->last_update_us > 0)
          ? (unsigned long long)(now_us - dequeue_stats->last_update_us) / 1000
          : 0,
      (accumulated_stats->tx_queue_last_readbuf_us > 0)
          ? (unsigned long long)(now_us -
                                 accumulated_stats->tx_queue_last_readbuf_us) /
                1000
          : 0);

  ave_size = 0;
  if (enqueue_stats->total_updates != 0)
    ave_size =
        accumulated_stats->tx_queue_total_frames / enqueue_stats->total_updates;
  dprintf(fd,
          "  Frames per packet (total/max/ave)                       : %zu / "
          "%zu / %zu\n",
          accumulated_stats->tx_queue_total_frames,
          accumulated_stats->tx_queue_max_frames_per_packet, ave_size);

  dprintf(fd,
          "  Counts (flushed/dropped/dropouts)                       : %zu / "
          "%zu / %zu\n",
          accumulated_stats->tx_queue_total_flushed_messages,
          accumulated_stats->tx_queue_total_dropped_messages,
          accumulated_stats->tx_queue_dropouts);

  dprintf(fd,
          "  Counts (max dropped)                                    : %zu\n",
          accumulated_stats->tx_queue_max_dropped_messages);

  dprintf(
      fd,
      "  Last update time ago in ms (flushed/dropped)            : %llu / "
      "%llu\n",
      (accumulated_stats->tx_queue_last_flushed_us > 0)
          ? (unsigned long long)(now_us -
                                 accumulated_stats->tx_queue_last_flushed_us) /
                1000
          : 0,
      (accumulated_stats->tx_queue_last_dropouts_us > 0)
          ? (unsigned long long)(now_us -
                                 accumulated_stats->tx_queue_last_dropouts_us) /
                1000
          : 0);

  dprintf(fd,
          "  Counts (underflow)                                      : %zu\n",
          accumulated_stats->media_read_total_underflow_count);

  dprintf(fd,
          "  Bytes (underflow)                                       : %zu\n",
          accumulated_stats->media_read_total_underflow_bytes);

  dprintf(fd,
          "  Last update time ago in ms (underflow)                  : %llu\n",
          (accumulated_stats->media_read_last_underflow_us > 0)
              ? (unsigned long long)(now_us -
                                     accumulated_stats
                                         ->media_read_last_underflow_us) /
                    1000
              : 0);

  //
  // TxQueue enqueue stats
  //
  dprintf(
      fd,
      "  Enqueue deviation counts (overdue/premature)            : %zu / %zu\n",
      enqueue_stats->overdue_scheduling_count,
      enqueue_stats->premature_scheduling_count);

  ave_time_us = 0;
  if (enqueue_stats->overdue_scheduling_count != 0) {
    ave_time_us = enqueue_stats->total_overdue_scheduling_delta_us /
                  enqueue_stats->overdue_scheduling_count;
  }
  dprintf(
      fd,
      "  Enqueue overdue scheduling time in ms (total/max/ave)   : %llu / %llu "
      "/ %llu\n",
      (unsigned long long)enqueue_stats->total_overdue_scheduling_delta_us /
          1000,
      (unsigned long long)enqueue_stats->max_overdue_scheduling_delta_us / 1000,
      (unsigned long long)ave_time_us / 1000);

  ave_time_us = 0;
  if (enqueue_stats->premature_scheduling_count != 0) {
    ave_time_us = enqueue_stats->total_premature_scheduling_delta_us /
                  enqueue_stats->premature_scheduling_count;
  }
  dprintf(
      fd,
      "  Enqueue premature scheduling time in ms (total/max/ave) : %llu / %llu "
      "/ %llu\n",
      (unsigned long long)enqueue_stats->total_premature_scheduling_delta_us /
          1000,
      (unsigned long long)enqueue_stats->max_premature_scheduling_delta_us /
          1000,
      (unsigned long long)ave_time_us / 1000);

  //
  // TxQueue dequeue stats
  //
  dprintf(
      fd,
      "  Dequeue deviation counts (overdue/premature)            : %zu / %zu\n",
      dequeue_stats->overdue_scheduling_count,
      dequeue_stats->premature_scheduling_count);

  ave_time_us = 0;
  if (dequeue_stats->overdue_scheduling_count != 0) {
    ave_time_us = dequeue_stats->total_overdue_scheduling_delta_us /
                  dequeue_stats->overdue_scheduling_count;
  }
  dprintf(
      fd,
      "  Dequeue overdue scheduling time in ms (total/max/ave)   : %llu / %llu "
      "/ %llu\n",
      (unsigned long long)dequeue_stats->total_overdue_scheduling_delta_us /
          1000,
      (unsigned long long)dequeue_stats->max_overdue_scheduling_delta_us / 1000,
      (unsigned long long)ave_time_us / 1000);

  ave_time_us = 0;
  if (dequeue_stats->premature_scheduling_count != 0) {
    ave_time_us = dequeue_stats->total_premature_scheduling_delta_us /
                  dequeue_stats->premature_scheduling_count;
  }
  dprintf(
      fd,
      "  Dequeue premature scheduling time in ms (total/max/ave) : %llu / %llu "
      "/ %llu\n",
      (unsigned long long)dequeue_stats->total_premature_scheduling_delta_us /
          1000,
      (unsigned long long)dequeue_stats->max_premature_scheduling_delta_us /
          1000,
      (unsigned long long)ave_time_us / 1000);
}

static void btif_a2dp_source_update_metrics(void) {
  BtifMediaStats stats = btif_a2dp_source_cb.stats;
  SchedulingStats enqueue_stats = stats.tx_queue_enqueue_stats;
  A2dpSessionMetrics metrics;
  metrics.codec_index = stats.codec_index;
  metrics.is_a2dp_offload = btif_av_is_a2dp_offload_running();
  // session_start_us is 0 when btif_a2dp_source_start_audio_req() is not called
  // mark the metric duration as invalid (-1) in this case
  if (stats.session_start_us != 0) {
    int64_t session_end_us = stats.session_end_us == 0
                                 ? bluetooth::common::time_get_os_boottime_us()
                                 : stats.session_end_us;
    if (static_cast<uint64_t>(session_end_us) > stats.session_start_us) {
      metrics.audio_duration_ms =
          (session_end_us - stats.session_start_us) / 1000;
    }
  }

  if (enqueue_stats.total_updates > 1) {
    metrics.media_timer_min_ms =
        btif_a2dp_source_cb.encoder_interval_ms -
        (enqueue_stats.max_premature_scheduling_delta_us / 1000);
    metrics.media_timer_max_ms =
        btif_a2dp_source_cb.encoder_interval_ms +
        (enqueue_stats.max_overdue_scheduling_delta_us / 1000);

    metrics.total_scheduling_count = enqueue_stats.overdue_scheduling_count +
                                     enqueue_stats.premature_scheduling_count +
                                     enqueue_stats.exact_scheduling_count;
    if (metrics.total_scheduling_count > 0) {
      metrics.media_timer_avg_ms = enqueue_stats.total_scheduling_time_us /
                                   (1000 * metrics.total_scheduling_count);
    }

    metrics.buffer_overruns_max_count = stats.tx_queue_max_dropped_messages;
    metrics.buffer_overruns_total = stats.tx_queue_total_dropped_messages;
    metrics.buffer_underruns_count = stats.media_read_total_underflow_count;
    metrics.buffer_underruns_average = 0;
    if (metrics.buffer_underruns_count > 0) {
      metrics.buffer_underruns_average =
          (float)stats.media_read_total_underflow_bytes /
          metrics.buffer_underruns_count;
    }
  }
  BluetoothMetricsLogger::GetInstance()->LogA2dpSession(metrics);
}

void btif_a2dp_source_set_dynamic_audio_buffer_size(
    uint8_t dynamic_audio_buffer_size) {
  btif_a2dp_source_dynamic_audio_buffer_size = dynamic_audio_buffer_size;
}

static void btm_read_rssi_cb(void* data) {
  if (data == nullptr) {
    LOG_ERROR("%s: Read RSSI request timed out", __func__);
    return;
  }

  tBTM_RSSI_RESULT* result = (tBTM_RSSI_RESULT*)data;
  if (result->status != BTM_SUCCESS) {
    LOG_ERROR("%s: unable to read remote RSSI (status %d)", __func__,
              result->status);
    return;
  }

  log_read_rssi_result(result->rem_bda,
                       bluetooth::common::kUnknownConnectionHandle,
                       result->hci_status, result->rssi);

  LOG_WARN("%s: device: %s, rssi: %d", __func__,
           result->rem_bda.ToString().c_str(), result->rssi);
}

static void btm_read_failed_contact_counter_cb(void* data) {
  if (data == nullptr) {
    LOG_ERROR("%s: Read Failed Contact Counter request timed out", __func__);
    return;
  }

  tBTM_FAILED_CONTACT_COUNTER_RESULT* result =
      (tBTM_FAILED_CONTACT_COUNTER_RESULT*)data;
  if (result->status != BTM_SUCCESS) {
    LOG_ERROR("%s: unable to read Failed Contact Counter (status %d)", __func__,
              result->status);
    return;
  }
  log_read_failed_contact_counter_result(
      result->rem_bda, bluetooth::common::kUnknownConnectionHandle,
      result->hci_status, result->failed_contact_counter);

  LOG_WARN("%s: device: %s, Failed Contact Counter: %u", __func__,
           result->rem_bda.ToString().c_str(), result->failed_contact_counter);
}

static void btm_read_tx_power_cb(void* data) {
  if (data == nullptr) {
    LOG_ERROR("%s: Read Tx Power request timed out", __func__);
    return;
  }

  tBTM_TX_POWER_RESULT* result = (tBTM_TX_POWER_RESULT*)data;
  if (result->status != BTM_SUCCESS) {
    LOG_ERROR("%s: unable to read Tx Power (status %d)", __func__,
              result->status);
    return;
  }
  log_read_tx_power_level_result(result->rem_bda,
                                 bluetooth::common::kUnknownConnectionHandle,
                                 result->hci_status, result->tx_power);

  LOG_WARN("%s: device: %s, Tx Power: %d", __func__,
           result->rem_bda.ToString().c_str(), result->tx_power);
}