/*--------------------------------------------------------------------------
   Author: Thomas Nowotny

   Institute: Institute for Nonlinear Dynamics
              University of California San Diego
              La Jolla, CA 92093-0402

   email to:  tnowotny@ucsd.edu

   initial version: 2005-08-17

--------------------------------------------------------------------------*/

#ifndef CN_ABSYNAPSE_CC
#define CN_ABSYNAPSE_CC

#include "CN_synapse.cc"

// This is the constructor to be used by derived classes passing the new
// internal var number, parameter number and type tag

absynapse::absynapse(neuron *insource, neuron *intarget,
		     double ingsyn, double inEsyn, double inEpre,
		     double inasyn, double inbsyn, double inrtime,
		     double nslevel,
		     int inIVARNO, int inPNO, int inTYPE):
  synapse(insource, intarget, inIVARNO, inPNO, inTYPE)
{
  p[0]= ingsyn;           // gsyn strength of synapse
  p[1]= inEsyn;           // Esyn reversal potential in mV
  p[2]= inEpre;           // Epre presyn threshold potential in mV
  p[3]= inasyn;           // alpha timescale in 1/msec
  p[4]= inbsyn;           // beta timescale in 1/msec
  p[5]= inrtime;       // time of transmitter release
  p[6]= nslevel;          // noise level
}

// This is the constructor to be used directly ...

absynapse::absynapse(neuron *insource, neuron *intarget,
		     double ingsyn, double inEsyn, double inEpre,
		     double inasyn, double inbsyn, double inrtime,
		     double nslevel):
  synapse(insource, intarget, ABSYNIVARNO, ABSYNPNO, ABSYN)
{
  p[0]= ingsyn;           // gsyn strength of synapse
  p[1]= inEsyn;           // Esyn reversal potential in mV
  p[2]= inEpre;           // Epre presyn threshold potential in mV
  p[3]= inasyn;           // alpha timescale in 1/msec
  p[4]= inbsyn;           // beta timescale in 1/msec
  p[5]= inrtime;       // time of transmitter release
  p[6]= nslevel;          // noise level
  tlast= -10000;
}

absynapse::absynapse(neuron *insource, neuron *intarget, double *inp):
  synapse(insource, intarget, ABSYNIVARNO, ABSYNPNO, ABSYN)
{
  set_p(inp);
  tlast= -10000;
}

absynapse::~absynapse()
{
}

double absynapse::gsyn()
{
  return p[0];
}

void absynapse::set_gsyn(double ingsyn)
{
  p[0]= ingsyn;
}

double absynapse::S(double *x)
{
  assert(enabled);
  return x[idx];
}


double absynapse::Isyn(double *x)
{
  return -p[0]*x[idx]*(target->E(x)-p[1]);
}


void absynapse::derivative(double *x, double *dx)
{
  static double dt;

  dt= x[0] - tlast;
  if ((dt >= 0) && (dt <= p[5])) {
    // continue release from an old spike
    //dx[idx]= p[3]*(1.0-x[idx]) - p[4]*x[idx];
	  dx[idx]= p[3] - p[4]*x[idx];

  } else {
    if ((source->E(x) > p[2]) && (dt > p[5]+1.0)) {
      // new spike ... start releasing
      tlast= x[0];
      //      cerr << tlast << endl;
     // dx[idx]= p[3]*(1.0-x[idx]) - p[4]*x[idx];
     dx[idx]= p[3] - p[4]*x[idx];
    }
    else {
      // no release
      dx[idx]= -p[4]*x[idx];
    }
  }
}

void absynapse::noise(double *x, double *dx)
{
 // dx[idx]= p[6]*abs(RG.n());
}

void absynapse::init(double *x, double *iniVars)
{
  tlast= -10000;
  synapse::init(x, iniVars);
}

// end of class implementation

#endif