// $Id$
//
//  Copyright (C) 2004-2008 Greg Landrum and Rational Discovery LLC
//
//  @@ All Rights Reserved @@
//  This file is part of the RDKit.
//  The contents are covered by the terms of the BSD license
//  which is included in the file license.txt, found at the root
//  of the RDKit source tree.
//
#include "DiscreteValueVect.h"
#include <RDGeneral/Invariant.h>
#include <RDGeneral/StreamOps.h>
#include "DatastructsException.h"
#include "DiscreteDistMat.h"
#include <RDBoost/Exceptions.h>
#include <boost/cstdint.hpp>

namespace RDKit {
  const int ci_DISCRETEVALUEVECTPICKLE_VERSION=0x1;

  DiscreteValueVect::DiscreteValueVect(const DiscreteValueVect &other) {
    d_type = other.getValueType();
    d_bitsPerVal = other.getNumBitsPerVal();
    d_numInts = other.getNumInts();
    d_length = other.getLength();
    d_valsPerInt = other.d_valsPerInt;
    d_mask = other.d_mask;
    const boost::uint32_t *odata = other.getData();
    boost::uint32_t *data = new boost::uint32_t[d_numInts];
    memcpy(static_cast<void *>(data), static_cast<const void *>(odata),
           d_numInts*sizeof(boost::uint32_t));
    d_data.reset(data);
  }

  unsigned int DiscreteValueVect::getVal(unsigned int i) const {
    if(i >= d_length){
      throw IndexErrorException(i);
    }
    unsigned int shift = d_bitsPerVal*(i%d_valsPerInt);
    unsigned int intId = i/d_valsPerInt;
    return ( (d_data[intId] >> shift) & d_mask);
  }

  void DiscreteValueVect::setVal(unsigned int i, unsigned int val) {
    if(i >= d_length){
      throw IndexErrorException(i);
    }
    if ((val & d_mask) != val) {
      throw ValueErrorException("Value out of range");
    }
    unsigned int shift = d_bitsPerVal*(i%d_valsPerInt);
    unsigned int intId = i/d_valsPerInt;
    unsigned int mask = ((1<<d_bitsPerVal) -1) << shift;
    mask = ~mask;
    d_data[intId] = (d_data[intId]&mask)|(val << shift);
  }

  unsigned int DiscreteValueVect::getTotalVal() const {
    unsigned int i, j, res = 0;
  
    for (i = 0; i < d_numInts; ++i) {
      for (j = 0; j < d_valsPerInt; ++j) {
        res += ((d_data[i] >> (j*d_bitsPerVal)) & d_mask);
      }
    }
    return res;
  }

  unsigned int DiscreteValueVect::getLength() const {
    return d_length;
  }

  const boost::uint32_t *DiscreteValueVect::getData() const {
    return d_data.get();
  }
  
  unsigned int computeL1Norm(const DiscreteValueVect &v1, const DiscreteValueVect &v2) {
    if (v1.getLength() != v2.getLength()) {
      throw ValueErrorException("Comparing vectors of different lengths");
    }

    DiscreteValueVect::DiscreteValueType valType = v1.getValueType();

    if (valType != v2.getValueType()) {
      throw ValueErrorException("Comparing vector of different value types");
    }

    const boost::uint32_t* data1 = v1.getData();
    const boost::uint32_t* data2 = v2.getData();

    unsigned int res = 0;
    if (valType <= DiscreteValueVect::EIGHTBITVALUE) {
      DiscreteDistMat *dmat = getDiscreteDistMat();
    
      unsigned char *cd1 = (unsigned char *)(data1);
      unsigned char *cd2 = (unsigned char *)(data2);
      const unsigned char *cend = cd1 + (v1.getNumInts()*4);
      while (cd1 != cend) {
        if (*cd1 == *cd2) {
          cd1++;
          cd2++;
          continue;
        }
        res += dmat->getDist(*cd1, *cd2, valType);
        cd1++;
        cd2++;
      }
    } else {
      // we have a sixteen bits per value type
      // REVIEW: we are making an assumption here that a short 
      // is 16 bit - may fail on a different compiler
      const unsigned short int *sd1 = (unsigned short int *)(data1);
      const unsigned short int *sd2 = (unsigned short int *)(data2);
    
      const unsigned short int *send = sd1 + (v1.getNumInts()*2);
      while (sd1 != send) {
        if (*sd1 == *sd2) {
          sd1++;
          sd2++;
          continue;
        }
        res += abs((*sd1) - (*sd2));
        sd1++;
        sd2++;
      }
    }
    return res;
  }

  std::string DiscreteValueVect::toString() const {
    std::stringstream ss(std::ios_base::binary|std::ios_base::out|std::ios_base::in);

    boost::int32_t tVers=ci_DISCRETEVALUEVECTPICKLE_VERSION*-1;
    streamWrite(ss,tVers);
    streamWrite(ss,d_type);
    boost::uint32_t tInt;
    tInt=d_bitsPerVal;
    streamWrite(ss,tInt);
    tInt=d_mask;
    streamWrite(ss,tInt);
    tInt=d_length;
    streamWrite(ss,tInt);
    tInt=d_numInts;
    streamWrite(ss,tInt);
    ss.write((const char *)d_data.get(),d_numInts*sizeof(tInt));
    
    std::string res(ss.str());
    return res;
  };

  void DiscreteValueVect::initFromText(const char *pkl,const unsigned int len){
    std::stringstream ss(std::ios_base::binary|std::ios_base::in|std::ios_base::out);
    ss.write(pkl,len);
    boost::int32_t tVers;
    streamRead(ss,tVers);
    tVers *= -1;
    if(tVers==0x1){
      
    } else {
      throw ValueErrorException("bad version in DiscreteValueVect pickle");
    }
    
    streamRead(ss,d_type);
    boost::uint32_t tInt;
    
    streamRead(ss,tInt);
    d_bitsPerVal=tInt;
    d_valsPerInt = BITS_PER_INT/d_bitsPerVal;
    streamRead(ss,tInt);
    d_mask=tInt;
    streamRead(ss,tInt);
    d_length=tInt;
    streamRead(ss,tInt);
    d_numInts=tInt;
    boost::uint32_t *data = new boost::uint32_t[d_numInts];
    ss.read((char *)data,d_numInts*sizeof(boost::uint32_t));
    d_data.reset(data);

  };


  DiscreteValueVect DiscreteValueVect::operator& (const DiscreteValueVect &other) const {
    PRECONDITION(other.d_length==d_length,"length mismatch");
    DiscreteValueType typ=d_type;
    if(other.d_type<typ){
      typ=other.d_type;
    }
    DiscreteValueVect ans(typ,d_length);
    for(unsigned int i=0;i<d_length;++i){
      unsigned int v1=getVal(i);
      unsigned int v2=other.getVal(i);
      if(v1<v2){
	ans.setVal(i,v1);
      }else{
	ans.setVal(i,v2);
      }
    }
    return(ans);
  };

  DiscreteValueVect DiscreteValueVect::operator|(const DiscreteValueVect &other) const {
    PRECONDITION(other.d_length==d_length,"length mismatch");
    DiscreteValueType typ=d_type;
    if(other.d_type>typ){
      typ=other.d_type;
    }
    DiscreteValueVect ans(typ,d_length);
    for(unsigned int i=0;i<d_length;++i){
      unsigned int v1=getVal(i);
      unsigned int v2=other.getVal(i);
      if(v1>v2){
	ans.setVal(i,v1);
      }else{
	ans.setVal(i,v2);
      }
    }
    return(ans);
  };

  DiscreteValueVect& DiscreteValueVect::operator+=(const DiscreteValueVect &other) {
    PRECONDITION(other.d_length==d_length,"length mismatch");
    unsigned int maxVal = (1<<d_bitsPerVal) - 1;

    for(unsigned int i=0;i<d_length;i++){
      unsigned int v=getVal(i)+other.getVal(i);
      if(v>maxVal){
	v=maxVal;
      }
      setVal(i,v);
    }
    return *this;
  }
  DiscreteValueVect& DiscreteValueVect::operator-=(const DiscreteValueVect &other) {
    PRECONDITION(other.d_length==d_length,"length mismatch");

    for(unsigned int i=0;i<d_length;i++){
      unsigned int v1=getVal(i);
      unsigned int v2=other.getVal(i);
      if(v1>v2){
	setVal(i,v1-v2);
      }else{
	setVal(i,0);
      }
    }
    return *this;
  }

#if 0
  DiscreteValueVect DiscreteValueVect::operator~() const {
    DiscreteValueVect ans(d_type,d_length);
    unsigned int maxVal = (1<<d_bitsPerVal) - 1;
    for(unsigned int i=0;i<d_length;++i){
      unsigned int v1=getVal(i);
      ans.setVal(i,maxVal-v1);
    }
    return(ans);
  };
#endif

  DiscreteValueVect operator+ (const DiscreteValueVect& p1,
			       const DiscreteValueVect& p2){
    DiscreteValueVect res(p1);
    res+=p2;
    return res;
  };
  DiscreteValueVect operator- (const DiscreteValueVect& p1,
			       const DiscreteValueVect& p2){
    DiscreteValueVect res(p1);
    res-=p2;
    return res;
  };


}   // end of namespace RDKit