/**
 *
 * \section COPYRIGHT
 *
 * Copyright 2013-2021 Software Radio Systems Limited
 *
 * By using this file, you agree to the terms and conditions set
 * forth in the LICENSE file which can be found at the top level of
 * the distribution.
 *
 */

#ifndef SRSUE_PROC_BSR_NR_H
#define SRSUE_PROC_BSR_NR_H

#include <map>
#include <stdint.h>

#include "proc_sr_nr.h"
#include "srsran/common/task_scheduler.h"
#include "srsran/mac/mac_sch_pdu_nr.h"
#include "srsran/srslog/srslog.h"
#include "srsue/hdr/stack/mac_common/mac_common.h"

/* Buffer status report procedure */

namespace srsue {

class rlc_interface_mac;

// BSR interface for MUX
class bsr_interface_mux_nr
{
public:
  // TS 38.321 Sec 6.1.3.1
  typedef enum { SHORT_BSR, LONG_BSR, SHORT_TRUNC_BSR, LONG_TRUNC_BSR } bsr_format_nr_t;

  /// MUX calls BSR to receive the buffer state of a single LCG.
  virtual srsran::mac_sch_subpdu_nr::lcg_bsr_t generate_sbsr() = 0;
};

class mux_interface_bsr_nr
{
public:
  /// Inform MUX unit to that a BSR needs to be generated in the next UL transmission.
  virtual void generate_bsr_mac_ce(const bsr_interface_mux_nr::bsr_format_nr_t& format) = 0;
};

/**
 * @brief  BSR procedure for NR according to 3GPP TS 38.321 version 15.3.0
 *
 * @remark: So far only class scelleton.
 */
class proc_bsr_nr : public srsran::timer_callback, public bsr_interface_mux_nr
{
public:
  explicit proc_bsr_nr(srslog::basic_logger& logger_) : logger(logger_) {}
  int  init(proc_sr_nr*                    sr_proc,
            mux_interface_bsr_nr*          mux_,
            rlc_interface_mac*             rlc,
            srsran::ext_task_sched_handle* task_sched_);
  void step(uint32_t tti, const mac_buffer_states_t& new_buffer_state);
  void reset();
  int  set_config(const srsran::bsr_cfg_nr_t& bsr_cfg);

  int      setup_lcid(uint32_t lcid, uint32_t lcg, uint32_t priority);
  void     timer_expired(uint32_t timer_id);

  /// Called by MAC when an UL grant is received
  void new_grant_ul(uint32_t grant_size);

  /// MUX interface for BSR generation
  srsran::mac_sch_subpdu_nr::lcg_bsr_t generate_sbsr();
  bool                                 generate_padding_bsr(uint32_t nof_padding_bytes);

private:
  const static int QUEUE_STATUS_PERIOD_MS = 1000;

  std::mutex mutex;

  srsran::ext_task_sched_handle* task_sched = nullptr;
  srslog::basic_logger&          logger;
  rlc_interface_mac*             rlc = nullptr;
  mux_interface_bsr_nr*          mux = nullptr;
  proc_sr_nr*                    sr  = nullptr;

  srsran::bsr_cfg_nr_t bsr_cfg = {};

  bool initiated = false;

  mac_buffer_states_t buffer_state;

  // map of LCGs and their priorities, key is the priority (sorted) and the value the LCG
  std::map<uint32_t, uint32_t> lcg_priorities;

  bsr_trigger_type_t triggered_bsr_type = NONE;

  void     print_state();
  void     set_trigger(bsr_trigger_type_t new_trigger);
  bool     check_highest_channel();
  bool     check_new_data(const mac_buffer_states_t& new_buffer_state);
  bool     check_any_channel();

  uint8_t buff_size_bytes_to_field(uint32_t buffer_size, bsr_format_nr_t format);

  uint32_t find_max_priority_lcg_with_data();

  srsran::timer_handler::unique_timer timer_periodic;
  srsran::timer_handler::unique_timer timer_retx;
  srsran::timer_handler::unique_timer timer_queue_status_print;
};

} // namespace srsue

#endif // SRSUE_PROC_BSR_NR_H