/*
 * Copyright 2022 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.
 */

#define LOG_TAG "BTAudioHearingAidAIDL"

#include "hearing_aid_software_encoding_aidl.h"

#include <bluetooth/log.h>

#include "audio_hearing_aid_hw/include/audio_hearing_aid_hw.h"
#include "client_interface_aidl.h"
#include "osi/include/properties.h"

namespace std {
template <>
struct formatter<audio_usage_t> : enum_formatter<audio_usage_t> {};
template <>
struct formatter<audio_content_type_t> : enum_formatter<audio_content_type_t> {};
}  // namespace std

namespace {

using ::aidl::android::hardware::bluetooth::audio::ChannelMode;
using ::aidl::android::hardware::bluetooth::audio::CodecType;
using ::bluetooth::audio::aidl::AudioConfiguration;
using ::bluetooth::audio::aidl::BluetoothAudioCtrlAck;
using ::bluetooth::audio::aidl::LatencyMode;
using ::bluetooth::audio::aidl::PcmConfiguration;
using ::bluetooth::audio::aidl::SessionType;
using ::bluetooth::audio::aidl::hearing_aid::StreamCallbacks;
using namespace bluetooth;

// Transport implementation for Hearing Aids
class HearingAidTransport : public bluetooth::audio::aidl::IBluetoothSinkTransportInstance {
public:
  HearingAidTransport(StreamCallbacks stream_cb)
      : IBluetoothSinkTransportInstance(SessionType::HEARING_AID_SOFTWARE_ENCODING_DATAPATH,
                                        (AudioConfiguration){}),
        stream_cb_(std::move(stream_cb)),
        remote_delay_report_ms_(0),
        total_bytes_read_(0),
        data_position_({}) {}

  BluetoothAudioCtrlAck StartRequest(bool /*is_low_latency*/) override {
    log::info("");
    if (stream_cb_.on_resume_(true)) {
      return BluetoothAudioCtrlAck::SUCCESS_FINISHED;
    }
    return BluetoothAudioCtrlAck::FAILURE;
  }

  BluetoothAudioCtrlAck SuspendRequest() override {
    log::info("");
    if (stream_cb_.on_suspend_()) {
      uint8_t p_buf[AUDIO_STREAM_OUTPUT_BUFFER_SZ * 2];
      ::bluetooth::audio::aidl::hearing_aid::read(p_buf, sizeof(p_buf));
      return BluetoothAudioCtrlAck::SUCCESS_FINISHED;
    } else {
      return BluetoothAudioCtrlAck::FAILURE;
    }
  }

  void StopRequest() override {
    log::info("");
    if (stream_cb_.on_suspend_()) {
      // flush
      uint8_t p_buf[AUDIO_STREAM_OUTPUT_BUFFER_SZ * 2];
      ::bluetooth::audio::aidl::hearing_aid::read(p_buf, sizeof(p_buf));
    }
  }

  void SetLatencyMode(LatencyMode /*latency_mode*/) override {}

  bool GetPresentationPosition(uint64_t* remote_delay_report_ns, uint64_t* total_bytes_read,
                               timespec* data_position) override {
    log::verbose("data={} byte(s), timestamp={}.{}s, delay report={} msec.", total_bytes_read_,
                 data_position_.tv_sec, data_position_.tv_nsec, remote_delay_report_ms_);
    if (remote_delay_report_ns != nullptr) {
      *remote_delay_report_ns = remote_delay_report_ms_ * 1000000u;
    }
    if (total_bytes_read != nullptr) {
      *total_bytes_read = total_bytes_read_;
    }
    if (data_position != nullptr) {
      *data_position = data_position_;
    }

    return true;
  }

  void SourceMetadataChanged(const source_metadata_v7_t& source_metadata) override {
    auto track_count = source_metadata.track_count;
    auto tracks = source_metadata.tracks;
    log::info("{} track(s) received", track_count);
    while (track_count) {
      log::verbose("usage={}, content_type={}, gain={}", tracks->base.usage,
                   tracks->base.content_type, tracks->base.gain);
      --track_count;
      ++tracks;
    }
  }

  void SinkMetadataChanged(const sink_metadata_v7_t&) override {}

  void ResetPresentationPosition() override {
    log::verbose("called.");
    remote_delay_report_ms_ = 0;
    total_bytes_read_ = 0;
    data_position_ = {};
  }

  void LogBytesRead(size_t bytes_read) override {
    if (bytes_read) {
      total_bytes_read_ += bytes_read;
      clock_gettime(CLOCK_MONOTONIC, &data_position_);
    }
  }

  void SetRemoteDelay(uint16_t delay_report_ms) {
    log::info("delay_report={} msec", delay_report_ms);
    remote_delay_report_ms_ = delay_report_ms;
  }

private:
  StreamCallbacks stream_cb_;
  uint16_t remote_delay_report_ms_;
  uint64_t total_bytes_read_;
  timespec data_position_;
};

bool HearingAidGetSelectedHalPcmConfig(PcmConfiguration* hal_pcm_config) {
  if (hal_pcm_config == nullptr) {
    return false;
  }
  // TODO: we only support one config for now!
  hal_pcm_config->sampleRateHz = 16000;
  hal_pcm_config->bitsPerSample = 16;
  hal_pcm_config->channelMode = ChannelMode::STEREO;
  return true;
}

// Sink instance of Hearing Aids to provide call-in APIs for Bluetooth Audio Hal
HearingAidTransport* hearing_aid_sink = nullptr;
// Common interface to call-out into Bluetooth Audio Hal
bluetooth::audio::aidl::BluetoothAudioSinkClientInterface* hearing_aid_hal_clientinterface =
        nullptr;

// Save the value if the remote reports its delay before hearing_aid_sink is
// initialized
uint16_t remote_delay_ms = 0;

}  // namespace

namespace bluetooth {
namespace audio {
namespace aidl {
namespace hearing_aid {

bool is_hal_enabled() { return hearing_aid_hal_clientinterface != nullptr; }

bool init(StreamCallbacks stream_cb, bluetooth::common::MessageLoopThread* /*message_loop*/) {
  log::info("");

  if (!BluetoothAudioClientInterface::is_aidl_available()) {
    log::error("BluetoothAudio AIDL implementation does not exist");
    return false;
  }

  hearing_aid_sink = new HearingAidTransport(std::move(stream_cb));
  hearing_aid_hal_clientinterface =
          new bluetooth::audio::aidl::BluetoothAudioSinkClientInterface(hearing_aid_sink);
  if (!hearing_aid_hal_clientinterface->IsValid()) {
    log::warn("BluetoothAudio HAL for Hearing Aid is invalid?!");
    delete hearing_aid_hal_clientinterface;
    hearing_aid_hal_clientinterface = nullptr;
    delete hearing_aid_sink;
    hearing_aid_sink = nullptr;
    return false;
  }

  if (remote_delay_ms != 0) {
    log::info("restore DELAY {} ms", remote_delay_ms);
    hearing_aid_sink->SetRemoteDelay(remote_delay_ms);
    remote_delay_ms = 0;
  }

  return true;
}

void cleanup() {
  log::info("");
  if (!is_hal_enabled()) {
    return;
  }
  end_session();
  delete hearing_aid_hal_clientinterface;
  hearing_aid_hal_clientinterface = nullptr;
  delete hearing_aid_sink;
  hearing_aid_sink = nullptr;
  remote_delay_ms = 0;
}

void start_session() {
  log::info("");
  if (!is_hal_enabled()) {
    return;
  }
  AudioConfiguration audio_config;
  PcmConfiguration pcm_config{};
  if (!HearingAidGetSelectedHalPcmConfig(&pcm_config)) {
    log::error("cannot get PCM config");
    return;
  }
  audio_config.set<AudioConfiguration::pcmConfig>(pcm_config);
  if (!hearing_aid_hal_clientinterface->UpdateAudioConfig(audio_config)) {
    log::error("cannot update audio config to HAL");
    return;
  }
  hearing_aid_hal_clientinterface->StartSession();
}

void end_session() {
  log::info("");
  if (!is_hal_enabled()) {
    return;
  }
  hearing_aid_hal_clientinterface->EndSession();
}

size_t read(uint8_t* p_buf, uint32_t len) {
  if (!is_hal_enabled()) {
    return 0;
  }
  return hearing_aid_hal_clientinterface->ReadAudioData(p_buf, len);
}

// Update Hearing Aids delay report to BluetoothAudio HAL
void set_remote_delay(uint16_t delay_report_ms) {
  if (!is_hal_enabled()) {
    log::info("not ready for DelayReport {} ms", delay_report_ms);
    remote_delay_ms = delay_report_ms;
    return;
  }
  log::info("delay_report_ms={} ms", delay_report_ms);
  hearing_aid_sink->SetRemoteDelay(delay_report_ms);
}

}  // namespace hearing_aid
}  // namespace aidl
}  // namespace audio
}  // namespace bluetooth