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#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "main_FLP.h"

/* Find LPC and LTP coefficients */

void silk_find_pred_coefs_FLP(

    silk_encoder_state_FLP          *psEnc,                             /* I/O  Encoder state FLP                           */

    silk_encoder_control_FLP        *psEncCtrl,                         /* I/O  Encoder control FLP                         */

    const silk_float                res_pitch[],                        /* I    Residual from pitch analysis                */

    const silk_float                x[],                                /* I    Speech signal                               */

    opus_int                        condCoding                          /* I    The type of conditional coding to use       */

)

{

    opus_int         i;

    silk_float       XXLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];

    silk_float       xXLTP[ MAX_NB_SUBFR * LTP_ORDER ];

    silk_float       invGains[ MAX_NB_SUBFR ];

    /* Set to NLSF_Q15 to zero so we don't copy junk to the state. */

    opus_int16       NLSF_Q15[ MAX_LPC_ORDER ]={0};

    const silk_float *x_ptr;

    silk_float       *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];

    silk_float       minInvGain;

    /* Weighting for weighted least squares */

    for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {

        silk_assert( psEncCtrl->Gains[ i ] > 0.0f );

        invGains[ i ] = 1.0f / psEncCtrl->Gains[ i ];

    }

    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {

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

        /* VOICED */

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

        celt_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );

        /* LTP analysis */

        silk_find_LTP_FLP( XXLTP, xXLTP, res_pitch, psEncCtrl->pitchL, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.arch );

        /* Quantize LTP gain parameters */

        silk_quant_LTP_gains_FLP( psEncCtrl->LTPCoef, psEnc->sCmn.indices.LTPIndex, &psEnc->sCmn.indices.PERIndex,

            &psEnc->sCmn.sum_log_gain_Q7, &psEncCtrl->LTPredCodGain, XXLTP, xXLTP, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.arch );

        /* Control LTP scaling */

        silk_LTP_scale_ctrl_FLP( psEnc, psEncCtrl, condCoding );

        /* Create LTP residual */

        silk_LTP_analysis_filter_FLP( LPC_in_pre, x - psEnc->sCmn.predictLPCOrder, psEncCtrl->LTPCoef,

            psEncCtrl->pitchL, invGains, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );

    } else {

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

        /* UNVOICED */

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

        /* Create signal with prepended subframes, scaled by inverse gains */

        x_ptr     = x - psEnc->sCmn.predictLPCOrder;

        x_pre_ptr = LPC_in_pre;

        for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {

            silk_scale_copy_vector_FLP( x_pre_ptr, x_ptr, invGains[ i ],

                psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder );

            x_pre_ptr += psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder;

            x_ptr     += psEnc->sCmn.subfr_length;

        }

        silk_memset( psEncCtrl->LTPCoef, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( silk_float ) );

        psEncCtrl->LTPredCodGain = 0.0f;

        psEnc->sCmn.sum_log_gain_Q7 = 0;

    }

    /* Limit on total predictive coding gain */

    if( psEnc->sCmn.first_frame_after_reset ) {

        minInvGain = 1.0f / MAX_PREDICTION_POWER_GAIN_AFTER_RESET;

    } else {

        minInvGain = (silk_float)pow( 2, psEncCtrl->LTPredCodGain / 3 ) /  MAX_PREDICTION_POWER_GAIN;

        minInvGain /= 0.25f + 0.75f * psEncCtrl->coding_quality;

    }

    /* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */

    silk_find_LPC_FLP( &psEnc->sCmn, NLSF_Q15, LPC_in_pre, minInvGain, psEnc->sCmn.arch );

    /* Quantize LSFs */

    silk_process_NLSFs_FLP( &psEnc->sCmn, psEncCtrl->PredCoef, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 );

    /* Calculate residual energy using quantized LPC coefficients */

    silk_residual_energy_FLP( psEncCtrl->ResNrg, LPC_in_pre, psEncCtrl->PredCoef, psEncCtrl->Gains,

        psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );

    /* Copy to prediction struct for use in next frame for interpolation */

    silk_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );

}