/*========================================================================
  PISA  (www.tik.ee.ethz.ch/pisa/)
  ========================================================================
  Computer Engineering (TIK)
  ETH Zurich
  ========================================================================
  SPAM - Set Preference Algorithm for Multiobjective Optimization

  authors: Johannes Bader, johannes.bader@tik.ee.ethz.ch
           Eckart Zitzler, eckart.zitzler@tik.ee.ethz.ch
           Marco Laumanns, laumanns@tik.ee.ethz.ch

  revision by: Stefan Bleuler, stefan.bleuler@tik.ee.ethz.ch
			   Dimo Brockhoff, dimo.brockhoff@tik.ee.ethz.ch

  last change: 01.12.2008
  ========================================================================
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "spam.h"
#include "population.h"

int read_pop(char *filename, pop *pp, int size, int dim )
/* Reads individuals from file into pop */
{
	int i, j;
	int entries = 0;
	char tag[4];
	FILE *fp;
	int result;

	assert(dim >= 0);
	assert(pp != NULL);

	fp = fopen(filename, "r");
	assert(fp != NULL);

	fscanf(fp, "%d", &entries);
	if (entries == 0) /* file has not been written yet */
	{
		return (1);  /* signalling that reading failed */
	}
	if( entries != size*(dim+1) )
	{
		fprintf(stderr,"The number of entries (%d) is not equal to "
				"size*(dim+1) [%d*(%d+1)]", entries, size, dim );
	}
	assert(entries == size * (dim + 1));
	assert( size <= pp->maxsize );
	assert( dim == pp->dim );

	for (j = 0; j < size; j++)
	{
		/* reading index of individual */
		result = fscanf(fp, "%d", &(pp->ind_array[j]->index));
		pp->size++;
		for (i = 0; i < dim; i++)
		{
			/* reading objective values of ind */
			double value;
			result = fscanf(fp, "%le", &value);
			pp->ind_array[j]->f_u[i] = value;
			pp->ind_array[j]->f_s[i] = value;

			if (result == EOF) /* file not completely written */
			{
				fclose(fp);
				return (1); /* signalling that reading failed */
			}
		}
	}

	/* after all data elements: "END" expected */
	fscanf(fp, "%s", tag);

	if (strcmp(tag, "END") != 0)
	{
		fclose(fp);
		return (1);  /* signalling that reading failed */
	}
	else /* "END" ok */
	{
		fclose(fp);

		/* delete file content if reading successful */
		fp = fopen(filename, "w");
		assert(fp != NULL);
		fprintf(fp, "0");
		fclose(fp);

		return (0);  /* signalling that reading was successful */
	}
}

void write_pop(char* filename, pop* pp, int size)
/* Writes a pop or PISA_to a given filename. */
{
	int i;
	FILE *fp;

	assert(0 <= size );
	assert( size <= pp->size);

	fp = fopen(filename, "w");
	assert(fp != NULL);

	fprintf(fp, "%d\n", size); /* number of elements */

	for (i = 0; i < size; i++)
	{
		fprintf(fp, "%d\n", pp->ind_array[i]->index);
	}
	fprintf(fp, "END");
	assert(fp != NULL);

	fclose(fp);
}

int check_file(char* filename)
{
	int control_element = 1;

	FILE *fp;

	fp = fopen(filename, "r");
	if( fp == NULL ) {
		printf("\nThe file >%s< does not exist!\n",filename);
	}
	assert(fp != NULL);
	fscanf(fp, "%d", &control_element);
	fclose(fp);

	if (0 == control_element)
		return (0); /* file is ready for writing */
	else
		return (1); /* file is not ready for writing */
}