#include <allegro.h>
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#include "bmp2txt.h"

static font_t* load_font(char* filename);

/* Initializes bmp2txt */
font_t* init_bmp2txt(void)
{
	return load_font("font");
}

/* Shuts down bmp2txt */
void cleanup_bmp2txt(font_t* font)
{
	free(font);
}

/* Plots an 8bpp grayscale BITMAP to screen using the given font */
void asciify_bmp(font_t* font, BITMAP* img)
{
	int y, x, v;
	int i = -1;
	printf("\033[H");
	for (y = 0; y < img->h; y++) {
		for (x = 0; x < img->w; x++) {
			v = getpixel(img, x, y);
			if (v < 36) {
				putchar(' '); continue;
			} else if (v < 36 * 2) {
				if (i != 0) {printf("\033[1;30m"); i = 0;}
			} else if (v < 36 * 3) {
				if (i != 1) {printf("\033[0;34m"); i = 1;}
			} else if (v < 36 * 4) {
				if (i != 2) {printf("\033[1;34m"); i = 2;}
			} else if (v < 36 * 5) {
				if (i != 3) {printf("\033[0;36m"); i = 3;}
			} else if (v < 36 * 6) {
				if (i != 4) {printf("\033[1;36m"); i = 4;}
			} else if (v < 36 * 7) {
				if (i != 5) {printf("\033[1;37m"); i = 5;}
			}
			putchar(font[v]);
		}
		putchar('\n');
	}
	fflush(stdout);
}

/* Load a font and return a map */
static font_t* load_font(char* filename)
{
	FILE* ffile = fopen(filename, "rb");
	int i, j, y, x, c, v, e;
	int min = -1, max = -1;
	int* font_count = malloc(sizeof(int) * 256);
	int* font_map = malloc(sizeof(int) * 256);

	/* Count number of set pixels in each glyph */
	for (i = 0; i < 256; i++) {
		font_count[i] = 0;
		for (y = 0; y < 16; y++) {
			c = fgetc(ffile);
			for (x = 0; x < 8; x++)
				if (c & (1 << x)) font_count[i]++;
		}
		if (!isprint(i)) {font_count[i] = -1; continue;}
		if (min == -1 || min > font_count[i]) min = font_count[i];
		if (max == -1 || max < font_count[i]) max = font_count[i];
	}
	
	/* Map values 0 - 255 to glyphs */
	for (i = 0; i < 256; i++) {
		/* Detarmine target value */
		v = (max - min) * i / 255 + min;

		/* Find nearest match to target value */
		e = -1;
		for (j = 0; j < 256; j++) {
			if (font_count[j] < 0) continue;
			if (e == -1 || abs(font_count[j] - v) < e) {
				e = abs(font_count[j] - v);
				font_map[i] = j;
			}
		}
	}

	free(font_count);
	fclose(ffile);

	return font_map;
}