/****************************************************************
 *      Program Solving the KNAPSACK problem using a heurustic  *
 *      Author Jakub Holy                                       *
 *      For the subject PAA, LS2002                             *
 ****************************************************************
 */

#include "hw1_heuristic.hh"
#include <iomanip.h>

// --------------------------------------------- CONST etc.
  HeurItem::HeurItem(int id, Item& it) : Item (it.weight, it.cost){
  HeurItem::id = id;
  ratio        = it.cost / it.weight;
}//HeurItem constr
// ----------------------------------------------------------
KnapsackProblem::KnapsackProblem(int task_id, int nr_items, int max_load, Item **items){
  // Parameters
  KnapsackProblem::task_id  = task_id;
  KnapsackProblem::nr_items = nr_items;
  KnapsackProblem::max_load = max_load;
  KnapsackProblem::items    = items;

  // Init other fields
  solution 	= new bool[nr_items];	// normally shall be init. to false manually ...
  load 		= 0;
  cost		= 0;

  // The Vector
  //  1. Init the vector: insert items
  for(int i=0; i < nr_items; i++){
    item_vect.push_back( *(new HeurItem(i, *(items[i]))));
  }// items -> item_vect

  //  2. Sort the items
  sort(item_vect.begin(), item_vect.end(), OptimalityCriterium() );
} // constructor

KnapsackProblem::~KnapsackProblem(){
  delete [] items;
  delete [] solution;
} //destructor

// --------------------------------------------- SOLVE
void KnapsackProblem::solve(void){
  int index = 0;
  for (TItem_vect::iterator iter = item_vect.begin(); iter != item_vect.end(); ++iter) {
    // Include the item, if not too heavy.
    if( ( load + iter->weight ) <= max_load ){
      solution[index] = true;		// include the item
      load += iter->weight;	// add its weight to the total load
      cost += iter->cost;  	// add its cost to the total one
    } else {
      solution[index] = false;
    }//if-else

    index++;
  }// for all elements in the vector
}//solve

// --------------------------------------------- PRINT
void KnapsackProblem::printResult(void){
  assert( solution!=0 );
  cout << cost<<endl;
}//printResult

//****************************************************************** MAIN

 int main(int argc, char **argv){
  //Open data file and load the 1st task
  if ( argc != 2 ) {
    cout << "Error: Wrong number of parameters.\n";
    cout << "Use: bruteforce taskfile\n"; 
  }// if wrong input
  KnapsackInput *in = new KnapsackInput( argv[1] );

  // For all tasks in the file:
  do {
    // Solve a task
    KnapsackProblem *problem = new KnapsackProblem(in->getTaskID(), in->getNr_items(), in->getMax_load(), in->getItems() );
    problem->solve();
    problem->printResult();
  } while ( in->loadNextTask() );
  //---------
  return 0;
 }// main