/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "intcnt.h"

IntCount::IntCount() : numInts(0), iPair(nullptr) { }
IntCount::~IntCount() { delete [] iPair;}
int IntCount::getSize() {return numInts;}
int IntCount::getCount(int pos) {return iPair[pos].cnt;}
int IntCount::getIndex(int pos) {return iPair[pos].idx;}

void IntCount::clear()
{
    delete[] iPair;
    iPair = new IntPair[0];
    numInts = 0;
}

int IntCount::countAdd(int index, int increment)
{
  if(numInts) {
    // Do a binary search to find the element
    int divPoint = 0;

    if(index>iPair[numInts-1].idx) {
	    divPoint = numInts;
    } else if(index<iPair[0].idx) {
	    divPoint = 0;
    } else {
	    int low=0, high=numInts-1;
	    int mid = (low+high)/2;
	    while(1) {
        mid = (low+high)/2;

        if(index<iPair[mid].idx) {
          high = mid;
        } else if(index>iPair[mid].idx) {
          if(mid<numInts-1 && index<iPair[mid+1].idx) {
            divPoint = mid+1;
            break;
          } else {
            low = mid+1;
          }
        } else if(index==iPair[mid].idx) {
          return iPair[mid].cnt += increment;
        }
	    }
    }

    int i;
    IntPair *tpair = new IntPair[numInts+1];
    for(i=0; i<divPoint; i++) {
      tpair[i] = iPair[i];
    }
    for(i=divPoint; i<numInts; i++) {
      tpair[i+1] = iPair[i];
    }
    ++numInts;
    delete [] iPair;
    iPair = tpair;
    iPair[divPoint].idx = index;
    iPair[divPoint].cnt = increment;
    return increment;
  } else {
    iPair = new IntPair[1];
    numInts = 1;
    iPair[0].idx = index;
    return iPair[0].cnt = increment;
  }
}
