#include "input.h"

#include <assert.h>
#include <fcntl.h>
#include <linux/input.h>
#include <string.h>
#include <unistd.h>

enum {
	RELEASE = 0,
	PRESS = 1,
	REPEAT = 2,
	NCALLBACKS,
};

static int input_fd;
static input_callback_t callbacks[NCALLBACKS];

int input_init()
{
	memset(callbacks, 0, sizeof(callbacks));

	input_fd = open("/dev/input/event0", O_RDONLY);
	assert(input_fd != -1);

	const int res = ioctl(input_fd, EVIOCGRAB, (void *)1);
	assert(res != -1);

	return input_fd;
}

void input_cleanup()
{
	ioctl(input_fd, EVIOCGRAB, (void *)0);
	close(input_fd);
}

void input_on_press(input_callback_t cb)
{
	callbacks[PRESS] = cb;
}

void input_on_release(input_callback_t cb)
{
	callbacks[RELEASE] = cb;
}

void input_on_repeat(input_callback_t cb)
{
	callbacks[REPEAT] = cb;
}

void input_handle()
{
	struct input_event ev;
	const int len = read(input_fd, &ev, sizeof(ev));
	assert(len == sizeof(ev));
	if (ev.type == EV_KEY && 0 <= ev.value && ev.value < NCALLBACKS) {
		if (callbacks[ev.value] != nullptr)
			callbacks[ev.value](ev.code);
	}
}