/***********************************************************************
Copyright (c) 2006-2012 IETF Trust and Skype Limited. All rights reserved.

This file is extracted from RFC6716. Please see that RFC for additional
information.

Redistribution and use in source and binary forms, with or without
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are met:
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names of specific contributors, may be used to endorse or promote
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS”
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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***********************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "main_FLP.h"
#include "tuning_parameters.h"

/* Processing of gains */
void silk_process_gains_FLP(
    silk_encoder_state_FLP          *psEnc,                             /* I/O  Encoder state FLP                           */
    silk_encoder_control_FLP        *psEncCtrl,                         /* I/O  Encoder control FLP                         */
    opus_int                        condCoding                          /* I    The type of conditional coding to use       */
)
{
    silk_shape_state_FLP *psShapeSt = &psEnc->sShape;
    opus_int     k;
    opus_int32   pGains_Q16[ MAX_NB_SUBFR ];
    silk_float   s, InvMaxSqrVal, gain, quant_offset;

    /* Gain reduction when LTP coding gain is high */
    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
        s = 1.0f - 0.5f * silk_sigmoid( 0.25f * ( psEncCtrl->LTPredCodGain - 12.0f ) );
        for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
            psEncCtrl->Gains[ k ] *= s;
        }
    }

    /* Limit the quantized signal */
    InvMaxSqrVal = ( silk_float )( pow( 2.0f, 0.33f * ( 21.0f - psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ) ) ) / psEnc->sCmn.subfr_length );

    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
        /* Soft limit on ratio residual energy and squared gains */
        gain = psEncCtrl->Gains[ k ];
        gain = ( silk_float )sqrt( gain * gain + psEncCtrl->ResNrg[ k ] * InvMaxSqrVal );
        psEncCtrl->Gains[ k ] = silk_min_float( gain, 32767.0f );
    }

    /* Prepare gains for noise shaping quantization */
    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
        pGains_Q16[ k ] = (opus_int32)( psEncCtrl->Gains[ k ] * 65536.0f );
    }

    /* Save unquantized gains and gain Index */
    silk_memcpy( psEncCtrl->GainsUnq_Q16, pGains_Q16, psEnc->sCmn.nb_subfr * sizeof( opus_int32 ) );
    psEncCtrl->lastGainIndexPrev = psShapeSt->LastGainIndex;

    /* Quantize gains */
    silk_gains_quant( psEnc->sCmn.indices.GainsIndices, pGains_Q16,
            &psShapeSt->LastGainIndex, condCoding == CODE_CONDITIONALLY, psEnc->sCmn.nb_subfr );

    /* Overwrite unquantized gains with quantized gains and convert back to Q0 from Q16 */
    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
        psEncCtrl->Gains[ k ] = pGains_Q16[ k ] / 65536.0f;
    }

    /* Set quantizer offset for voiced signals. Larger offset when LTP coding gain is low or tilt is high (ie low-pass) */
    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
        if( psEncCtrl->LTPredCodGain + psEnc->sCmn.input_tilt_Q15 * ( 1.0f / 32768.0f ) > 1.0f ) {
            psEnc->sCmn.indices.quantOffsetType = 0;
        } else {
            psEnc->sCmn.indices.quantOffsetType = 1;
        }
    }

    /* Quantizer boundary adjustment */
    quant_offset = silk_Quantization_Offsets_Q10[ psEnc->sCmn.indices.signalType >> 1 ][ psEnc->sCmn.indices.quantOffsetType ] / 1024.0f;
    psEncCtrl->Lambda = LAMBDA_OFFSET
                      + LAMBDA_DELAYED_DECISIONS * psEnc->sCmn.nStatesDelayedDecision
                      + LAMBDA_SPEECH_ACT        * psEnc->sCmn.speech_activity_Q8 * ( 1.0f /  256.0f )
                      + LAMBDA_INPUT_QUALITY     * psEncCtrl->input_quality
                      + LAMBDA_CODING_QUALITY    * psEncCtrl->coding_quality
                      + LAMBDA_QUANT_OFFSET      * quant_offset;

    silk_assert( psEncCtrl->Lambda > 0.0f );
    silk_assert( psEncCtrl->Lambda < 2.0f );
}
