#define DEBUG_DAC 1
#include <math.h>
#include <stdio.h>
#include "PHY/TOOLS/defs.h"

void dac(double **s_re,
	 double **s_im,
	 uint32_t **input,
	 uint32_t input_offset,
	 uint32_t nb_tx_antennas,
	 uint32_t length,
	 double amp_dBm,
	 uint8_t B,
	 uint32_t meas_length,
	 uint32_t meas_offset) {

  int i;
  int aa;
  double V=0.0,amp;

  for (i=0;i<length;i++) {
    for (aa=0;aa<nb_tx_antennas;aa++) {
      s_re[aa][i] = ((double)(((short *)input[aa]))[((i+input_offset)<<1)])/(1<<(B-1));
      s_im[aa][i] = ((double)(((short *)input[aa]))[((i+input_offset)<<1)+1])/(1<<(B-1));

    }
  }

  for (i=meas_offset;i<meas_offset+meas_length;i++) {
    for (aa=0;aa<nb_tx_antennas;aa++) {
      V= V + (s_re[aa][i]*s_re[aa][i]) + (s_im[aa][i]*s_im[aa][i]); 
    }
  }
  V /= (meas_length);
#ifdef DEBUG_DAC
  printf("DAC: 10*log10(V)=%f (%f)\n",10*log10(V),V);
#endif
  if (V) {
    amp = pow(10.0,.1*amp_dBm)/V;
    amp = sqrt(amp);
  } else {
    amp = 1;
  }

  for (i=0;i<length;i++) {
    for (aa=0;aa<nb_tx_antennas;aa++) {
      s_re[aa][i] *= amp;
      s_im[aa][i] *= amp;
    }
  }
}

double dac_fixed_gain(double **s_re,
		      double **s_im,
		      uint32_t **input,
		      uint32_t input_offset,
		      uint32_t nb_tx_antennas,
		      uint32_t length,
		      uint32_t input_offset_meas,
		      uint32_t length_meas,
		      uint8_t B,
		      double txpwr_dBm) {

  int i;
  int aa;
  double amp,amp1;
 
  amp = pow(10.0,.05*txpwr_dBm)/sqrt(nb_tx_antennas); //this is amp per tx antenna

  amp1 = 0;
  for (aa=0;aa<nb_tx_antennas;aa++) {
    amp1 += sqrt((double)signal_energy((int32_t*)&input[aa][input_offset_meas],length_meas) * (512.0/300.0));
  }
  amp1/=nb_tx_antennas;

  //printf("UL: amp1 %f dB (%d,%d), tx_power %f\n",20*log10(amp1),input_offset,input_offset_meas,txpwr_dBm);

  /*
    if (nb_tx_antennas==2)
      amp1 = AMP/2;
    else if (nb_tx_antennas==4)
      amp1 = ((AMP*ONE_OVER_SQRT2_Q15)>>16);
    else //assume (nb_tx_antennas==1) 
      amp1 = ((AMP*ONE_OVER_SQRT2_Q15)>>15);
    amp1 = amp1*sqrt(512.0/300.0); //account for loss due to null carriers
    //printf("DL: amp1 %f dB (%d,%d), tx_power %f\n",20*log10(amp1),input_offset,input_offset_meas,txpwr_dBm);
  */
  
  for (i=0;i<length;i++) {
    for (aa=0;aa<nb_tx_antennas;aa++) {
      s_re[aa][i] = amp*((double)(((short *)input[aa]))[((i+input_offset)<<1)])/amp1; ///(1<<(B-1));
      s_im[aa][i] = amp*((double)(((short *)input[aa]))[((i+input_offset)<<1)+1])/amp1; ///(1<<(B-1));

    }
  }

  //  printf("ener %e\n",signal_energy_fp(s_re,s_im,nb_tx_antennas,length,0));

  return(signal_energy_fp(s_re,s_im,nb_tx_antennas,512,0));
}