//--------------------------------------------------------------------------
//
// Environment:
//      This software is part of the EvtGen package developed jointly
//      for the BaBar and CLEO collaborations.  If you use all or part
//      of it, please give an appropriate acknowledgement.
//
// Copyright Information: See EvtGen/COPYRIGHT
//      Copyright (C) 1998      Caltech, UCSB
//
// Module: EvtGenModels/EvtBToPlnuBK.cc
//
// Description: B->Xu l nu with BK (Becirevic-Kaidalov) parametrization
//              Xu is a pseudoscalar (pi_plus,pi0,eta or eta_prime)
//
// Modification history:
//
//    Martin Simard, U. de Montreal, 08/01/2007    Module created
//
//------------------------------------------------------------------------
//
#include "EvtGenBase/EvtPatches.hh"
#include <stdlib.h>
#include <assert.h>
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtReport.hh"
#include "EvtGenModels/EvtBToPlnuBK.hh"
#include "EvtGenModels/EvtBToPlnuBKFF.hh"
#include "EvtGenBase/EvtSemiLeptonicScalarAmp.hh"

using std::fstream;
using std::cout;
using std::endl;


EvtBToPlnuBK::EvtBToPlnuBK():
  BKmodel(0)
  ,calcamp(0)
{}

EvtBToPlnuBK::~EvtBToPlnuBK(){  
  delete BKmodel;
  BKmodel=0;
  delete calcamp;
  calcamp=0;
}

std::string EvtBToPlnuBK::getName(){
  
  return "BTOPLNUBK";

}

EvtDecayBase* EvtBToPlnuBK::clone(){
  
  return new EvtBToPlnuBK;
  
}


void EvtBToPlnuBK::initProbMax(){
  
  EvtId parnum,mesnum,lnum,nunum;
  
  parnum = getParentId();
  mesnum = getDaug(0);
  lnum = getDaug(1);
  nunum = getDaug(2);
  
  double mymaxprob = calcamp->CalcMaxProb(parnum,mesnum,
					  lnum,nunum,BKmodel);
  
  setProbMax(mymaxprob);

}

void EvtBToPlnuBK::init(){

  checkNDaug(3);

  //We expect the parent to be a scalar 
  //and the daughters to be X lepton neutrino
  checkSpinParent(EvtSpinType::SCALAR);

  checkSpinDaughter(1,EvtSpinType::DIRAC);
  checkSpinDaughter(2,EvtSpinType::NEUTRINO);

  EvtSpinType::spintype d1type = EvtPDL::getSpinType(getDaug(0));
  if ( d1type==EvtSpinType::SCALAR) {
    checkNArg(2);
    BKmodel = new EvtBToPlnuBKFF(getArg(0),getArg(1));
    calcamp = new EvtSemiLeptonicScalarAmp; 
  }
  else{
    report(ERROR,"EvtGen") << "BK model handles only scalar meson daughters. Sorry."<<endl;
    ::abort();
  }

}

void  EvtBToPlnuBK::decay( EvtParticle *p ){

  p->initializePhaseSpace(getNDaug(),getDaugs());
  calcamp->CalcAmp(p,_amp2,BKmodel);

}