#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include "svm_rbf.h"

double *load_ay (char *filename)
{
	int i;
	double *ay = malloc(sizeof(double) * NUM_SUPPORT_VECTORS);
	FILE *fp = fopen(filename, "rt");

	for (i = 0; i < NUM_SUPPORT_VECTORS; i++) {
		const char *separators = " \t";
		char line[1024];
		char *current;
		fgets(line, sizeof(line) - 1, fp);
		ay[i] = strtod(line, NULL);
//		printf("val=%lf\n", ay[i]);
	}
	fclose(fp);

	return ay;
}

double *load_VS (char *filename)
{
	int i, j;
	double *VS = malloc(sizeof(double) * FEATURE_VECTOR_LENGTH * NUM_SUPPORT_VECTORS);
	FILE *fp = fopen(filename, "rt");
	int const MAX_LINE_LENGTH = 1024 * 1024;
	char *line = (char *) malloc(sizeof(char) * MAX_LINE_LENGTH);

	for (i = 0; i < NUM_SUPPORT_VECTORS; i++) {
		const char *separators = " \t";
		char *current;
		fgets(line, MAX_LINE_LENGTH - 1, fp);

		current = strtok(line, separators);
		for (j = 0; j < FEATURE_VECTOR_LENGTH; j++) {
			VS[i*FEATURE_VECTOR_LENGTH + j] = strtod(current, NULL);
			current = strtok(NULL, separators);
//			printf("%lf ", VS[i*FEATURE_VECTOR_LENGTH + j]);
		}
//		printf("\n");
	}
	fclose(fp);
	free(line);
	
	return VS;
}

/*
   h=histogram representation [1xFEATURE_VECTOR_LENGTH]
   VS = support vector in histogram representation [NUM_SUPPORT_VECTORSxFEATURE_VECTOR_LENGTH].
   ay = coefficients of support [NUM_SUPPORT_VECTORSx1]
    g = gaussian width  [1x1]
 */
double svm_rbf (double *h, double *VS, double *ay, double g)
{
	int i, j;
	double y = 0;
	double D[FEATURE_VECTOR_LENGTH];
	double D2;

	for (i = 0; i < NUM_SUPPORT_VECTORS; i++) {
		D2 = 0;
		for (j = 0; j < FEATURE_VECTOR_LENGTH; j++) {
			D[j] = h[j] - VS[i*FEATURE_VECTOR_LENGTH + j];
			D2 += D[j] * D[j];
		}
		y += ay[i]*exp(-0.5*D2/g);
		printf("%% y=%lf\n", y);
	}

	return y;
}