/******************************************************************************

 *                                                                            *

 * Copyright (C) 2023 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.

 *

 *****************************************************************************

 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore

 */

#include "ixheaac_type_def.h"

#include "ixheaac_constants.h"

#include "ixheaace_aac_constants.h"

#include <stdlib.h>

#include "ixheaace_psy_const.h"

#include "ixheaace_tns.h"

#include "ixheaace_tns_params.h"

#include "ixheaace_rom.h"

#include "ixheaace_common_rom.h"

#include "ixheaace_bitbuffer.h"

#include "ixheaac_basic_ops32.h"

#include "ixheaac_basic_ops16.h"

#include "ixheaac_basic_ops40.h"

#include "ixheaac_basic_ops.h"

#include <math.h>

#include "ixheaace_block_switch.h"

#include "ixheaace_psy_utils_spreading.h"

#include "ixheaace_psy_utils.h"

#include "ixheaace_calc_ms_band_energy.h"

#include "ixheaace_psy_configuration.h"

#include "ixheaace_psy_data.h"

#include "ixheaace_ms_stereo.h"

#include "ixheaace_common_utils.h"

VOID iaace_ms_apply(ixheaace_psy_data **ptr_psy_data, FLOAT32 *ptr_spec_left,

                    FLOAT32 *ptr_spec_right, WORD32 *ptr_ms_select, WORD32 *ptr_ms_used,

                    const WORD32 sfb_count, const WORD32 sfb_per_group,

                    const WORD32 max_sfb_per_grp, const WORD32 *ptr_sfb_offset,

                    FLOAT32 *ptr_weight_ms_lr_pe_ratio) {

  FLOAT32 *ptr_sfb_enegry_left = ptr_psy_data[0]->sfb_energy.long_nrg;

  FLOAT32 *ptr_sfb_energy_right = ptr_psy_data[1]->sfb_energy.long_nrg;

  const FLOAT32 *ptr_sfb_energy_mid = ptr_psy_data[0]->sfb_energy_ms.long_nrg;

  const FLOAT32 *ptr_sfb_energy_side = ptr_psy_data[1]->sfb_energy_ms.long_nrg;

  FLOAT32 *ptr_sfb_thr_left = ptr_psy_data[0]->sfb_threshold.long_nrg;

  FLOAT32 *ptr_sfb_thr_right = ptr_psy_data[1]->sfb_threshold.long_nrg;

  FLOAT32 *ptr_sfb_spread_energy_left = ptr_psy_data[0]->sfb_sreaded_energy.long_nrg;

  FLOAT32 *ptr_sfb_spread_energy_right = ptr_psy_data[1]->sfb_sreaded_energy.long_nrg;

  WORD32 sfb, sfb_offsets, j;

  WORD32 grp = 0;

  WORD32 ms_counter = 0;

  WORD32 lr_counter = 0;

  FLOAT32 sum_ss_sr_pe_ratio = 0;

  WORD32 cnt = 0;

  FLOAT32 atan_val;

  *ptr_ms_select = 0;

  for (sfb = 0; sfb < sfb_count; sfb += sfb_per_group, grp++) {

    for (sfb_offsets = 0; sfb_offsets < max_sfb_per_grp; sfb_offsets++) {

      FLOAT32 left_right, mid_side, min_thr;

      WORD32 use_ms;

      ptr_ms_used[sfb + sfb_offsets] = 0;

      min_thr = MIN(ptr_sfb_thr_left[sfb + sfb_offsets], ptr_sfb_thr_right[sfb + sfb_offsets]);

      left_right =

          (ptr_sfb_thr_left[sfb + sfb_offsets] /

           MAX(ptr_sfb_enegry_left[sfb + sfb_offsets], ptr_sfb_thr_left[sfb + sfb_offsets])) *

          (ptr_sfb_thr_right[sfb + sfb_offsets] /

           MAX(ptr_sfb_energy_right[sfb + sfb_offsets], ptr_sfb_thr_right[sfb + sfb_offsets]));

      mid_side = (min_thr / MAX(ptr_sfb_energy_mid[sfb + sfb_offsets], min_thr)) *

                 (min_thr / MAX(ptr_sfb_energy_side[sfb + sfb_offsets], min_thr));

      sum_ss_sr_pe_ratio += (left_right + 1.0e-9f) / (mid_side + 1.0e-9f);

      cnt++;

      use_ms = (mid_side >= left_right);

      if (use_ms) {

        ptr_ms_used[sfb + sfb_offsets] = 1;

        for (j = ptr_sfb_offset[sfb + sfb_offsets]; j < ptr_sfb_offset[sfb + sfb_offsets + 1];

             j++) {

          FLOAT32 tmp = ptr_spec_left[j];

          ptr_spec_left[j] = 0.5f * (ptr_spec_left[j] + ptr_spec_right[j]);

          ptr_spec_right[j] = 0.5f * (tmp - ptr_spec_right[j]);

        }

        ptr_sfb_thr_left[sfb + sfb_offsets] = ptr_sfb_thr_right[sfb + sfb_offsets] = min_thr;

        ptr_sfb_enegry_left[sfb + sfb_offsets] = ptr_sfb_energy_mid[sfb + sfb_offsets];

        ptr_sfb_energy_right[sfb + sfb_offsets] = ptr_sfb_energy_side[sfb + sfb_offsets];

        ptr_sfb_spread_energy_left[sfb + sfb_offsets] =

            ptr_sfb_spread_energy_right[sfb + sfb_offsets] =

                MIN(ptr_sfb_spread_energy_left[sfb + sfb_offsets],

                    ptr_sfb_spread_energy_right[sfb + sfb_offsets]) *

                0.5f;

        ms_counter++;

      } else {

        ptr_ms_used[sfb + sfb_offsets] = 0;

        lr_counter++;

      }

    }

  }

  if (ms_counter == 0) {

    *ptr_ms_select = 0;

  } else {

    if (lr_counter != 0) {

      *ptr_ms_select = 1;

    } else {

      *ptr_ms_select = 2;

    }

  }

  cnt = MAX(1, cnt);

  atan_val = iaace_atan_approx((FLOAT32)(0.37f * (sum_ss_sr_pe_ratio / cnt - 6.5f)));

  *ptr_weight_ms_lr_pe_ratio = (FLOAT32)((0.28f * atan_val) + 1.25f);

}