#include <stdlib.h>

#include <string.h>

#include "mixer_clickable.h"

extern int screen_cols;

extern int screen_lines;

static struct clickable_rect *clickable_rects = NULL;

static unsigned int clickable_rects_count = 0;

static unsigned int last_rect = 0;

/* Using 0 instead of -1 for marking free rectangles allows us to use

 * memset for `freeing` all rectangles at once.

 * Zero is actually a valid coordinate in ncurses, but since we don't have

 * any clickables in the top line this is fine. */

#define FREE_MARKER 0

#define RECT_IS_FREE(RECT) ((RECT).y1 == FREE_MARKER)

#define RECT_FREE(RECT) ((RECT).y1 = FREE_MARKER)

void clickable_set(int y1, int x1, int y2, int x2, command_enum command, int arg1) {

	struct clickable_rect* tmp;

	unsigned int i;

	for (i = last_rect; i < clickable_rects_count; ++i) {

		if (RECT_IS_FREE(clickable_rects[i])) {

			last_rect = i;

			goto SET_CLICKABLE_DATA;

		}

	}

	for (i = 0; i < last_rect; ++i) {

		if (RECT_IS_FREE(clickable_rects[i])) {

			last_rect = i;

			goto SET_CLICKABLE_DATA;

		}

	}

	last_rect = clickable_rects_count;

	tmp = realloc(clickable_rects, (clickable_rects_count + 8) * sizeof(*clickable_rects));

	if (!tmp) {

		free(clickable_rects);

		clickable_rects = NULL;

		clickable_rects_count = 0;

		last_rect = 0;

		return;

	}

	clickable_rects = tmp;

#if FREE_MARKER == 0

	memset(clickable_rects + clickable_rects_count, 0, 8 * sizeof(*clickable_rects));

#else

	for (i = clickable_rects_count; i < clickable_rects_count + 8; ++i)

		RECT_FREE(clickable_rects[i]);

#endif

	clickable_rects_count += 8;

SET_CLICKABLE_DATA:

	clickable_rects[last_rect] = (struct clickable_rect) {

		.y1 = y1,

		.x1 = x1,

		.x2 = x2,

		.y2 = y2,

		.command = command,

		.arg1 = arg1

	};

}

void clickable_set_relative(WINDOW *win, int y1, int x1, int y2, int x2, command_enum command, int arg1) {

	int y, x;

	getyx(win, y, x);

	y1 = y + y1;

	x1 = x + x1;

	y2 = y + y2;

	x2 = x + x2;

	clickable_set(y1, x1, y2, x2, command, arg1);

}

void clickable_clear(int y1, int x1, int y2, int x2) {

#define IS_IN_RECT(Y, X) (Y >= y1 && Y <= y2 && X >= x1 && X <= x2)

	unsigned int i;

	if (x1 == 0 && x2 == -1 && y2 == -1) {

		if (y1 == 0) {

			// Optimize case: clear all

#if FREE_MARKER == 0

			if (clickable_rects)

				memset(clickable_rects, 0,

						clickable_rects_count * sizeof(*clickable_rects));

#else

			for (i = 0; i < clickable_rects_count; ++i)

				RECT_FREE(clickable_rects[i]);

#endif

		}

		else {

			// Optimize case: clear all lines beyond y1

			for (i = 0; i < clickable_rects_count; ++i) {

				if (clickable_rects[i].y2 >= y1)

					RECT_FREE(clickable_rects[i]);

			}

		}

		return;

	}

	if (y2 < 0)

		y2 = screen_lines + y2 + 1;

	if (x2 < 0)

		x2 = screen_cols + x2 + 1;

	for (i = 0; i < clickable_rects_count; ++i) {

		if (!RECT_IS_FREE(clickable_rects[i]) && (

				IS_IN_RECT(clickable_rects[i].y1, clickable_rects[i].x1) ||

				IS_IN_RECT(clickable_rects[i].y2, clickable_rects[i].x2)

			))

		{

			RECT_FREE(clickable_rects[i]);

		}

	}

}

struct clickable_rect* clickable_find(int y, int x) {

	unsigned int i;

	for (i = 0; i < clickable_rects_count; ++i) {

		if (

				!RECT_IS_FREE(clickable_rects[i]) &&

				y >= clickable_rects[i].y1 &&

				x >= clickable_rects[i].x1 &&

				y <= clickable_rects[i].y2 &&

				x <= clickable_rects[i].x2

			)

		{

			return &clickable_rects[i];

		}

	}

	return NULL;

}