/*
 * Copyright (c) 2008-2016 Stefan Krah. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */


#include mpdecimal_header
#include <stdio.h>
#include <time.h>


/*
 * Example from: http://en.wikipedia.org/wiki/Mandelbrot_set
 *
 * Escape time algorithm for drawing the set:
 *
 * Point x0, y0 is deemed to be in the Mandelbrot set if the return
 * value is maxiter. Lower return values indicate how quickly points
 * escaped and can be used for coloring.
 */
int
color_point(mpd_t *x0, mpd_t *y0, int maxiter, mpd_context_t *ctx)
{
	mpd_t *x, *y, *sq_x, *sq_y;
	mpd_t *two, *four, *c;
	int i;

	x = mpd_new(ctx);
	y = mpd_new(ctx);
	mpd_set_u32(x, 0, ctx);
	mpd_set_u32(y, 0, ctx);

	sq_x = mpd_new(ctx);
	sq_y = mpd_new(ctx);
	mpd_set_u32(sq_x, 0, ctx);
	mpd_set_u32(sq_y, 0, ctx);

	two = mpd_new(ctx);
	four = mpd_new(ctx);
	mpd_set_u32(two, 2, ctx);
	mpd_set_u32(four, 4, ctx);

	c = mpd_new(ctx);
	mpd_set_u32(c, 0, ctx);

	for (i = 0; i < maxiter && mpd_cmp(c, four, ctx) <= 0; i++) {

		mpd_mul(y, x, y, ctx);
		mpd_mul(y, y, two, ctx);
		mpd_add(y, y, y0, ctx);

		mpd_sub(x, sq_x, sq_y, ctx);
		mpd_add(x, x, x0, ctx);

		mpd_mul(sq_x, x, x, ctx);
		mpd_mul(sq_y, y, y, ctx);
		mpd_add(c, sq_x, sq_y, ctx);
	}

	mpd_del(x);
	mpd_del(y);
	mpd_del(sq_x);
	mpd_del(sq_y);
	mpd_del(two);
	mpd_del(four);
	mpd_del(c);

	return i;
}

int
main(int argc, char **argv)
{
	mpd_context_t ctx;
	mpd_t *x0, *y0;
	mpd_t *sqrt_2, *xstep, *ystep;
	uint32_t prec = 19;

	int iter = 1000;
	int points[40][80];
	int i, j;
	clock_t start_clock, end_clock;


	if (argc != 3) {
		fprintf(stderr, "usage: ./bench prec iter\n");
		exit(1);
	}
	prec = strtoul(argv[1], NULL, 10);
	iter = strtol(argv[2], NULL, 10);

	mpd_init(&ctx, prec);
	/* no more MPD_MINALLOC changes after here */

	sqrt_2 = mpd_new(&ctx);
	xstep = mpd_new(&ctx);
	ystep = mpd_new(&ctx);
	x0 = mpd_new(&ctx);
	y0 = mpd_new(&ctx);

	mpd_set_u32(sqrt_2, 2, &ctx);
	mpd_sqrt(sqrt_2, sqrt_2, &ctx);
	mpd_div_u32(xstep, sqrt_2, 40, &ctx);
	mpd_div_u32(ystep, sqrt_2, 20, &ctx);

	start_clock = clock();
	mpd_copy(y0, sqrt_2, &ctx);
	for (i = 0; i < 40; i++) {
		mpd_copy(x0, sqrt_2, &ctx);
		mpd_set_negative(x0);
		for (j = 0; j < 80; j++) {
			points[i][j] = color_point(x0, y0, iter, &ctx);
			mpd_add(x0, x0, xstep, &ctx);
		}
		mpd_sub(y0, y0, ystep, &ctx);
	}
	end_clock = clock();

#ifdef BENCH_VERBOSE
	for (i = 0; i < 40; i++) {
		for (j = 0; j < 80; j++) {
			if (points[i][j] == iter) {
				putchar('*');
			}
			else if (points[i][j] >= 10) {
				putchar('+');
			}
			else if (points[i][j] >= 5) {
				putchar('.');
			}
			else {
				putchar(' ');
			}
		}
		putchar('\n');
	}
	putchar('\n');
#endif

	printf("time: %f\n\n", (double)(end_clock-start_clock)/(double)CLOCKS_PER_SEC);

	mpd_del(x0);
	mpd_del(y0);
	mpd_del(sqrt_2);
	mpd_del(xstep);
	mpd_del(ystep);

	return 0;
}