layout.h

/* This file is part of ukbdc.
 *
 * ukbdc is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * ukbdc is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ukbdc; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#pragma once

#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>

#define NONE	0x00
#define REL	0x01
#define ABS	0x02

#define DOWN	1
#define UP	0

#define ACT(dir, type) ((type) << (4*(dir)))

struct layout_key {
	/* scan code to send
	 * 0 means no scancode */
	uint8_t scode;
	/* low 4 bits:  action type on key-down event
	 * high 4 bits: action type on key-up event */
	uint8_t actions;
	/* arguments to down- and up-action, respectively */
	uint8_t down_arg;
	uint8_t up_arg;
};

struct layout {
	uint8_t num_keys;
	uint8_t num_layers;
	/* pointer to program space */
	struct layout_key data[];
};

struct layout_state {
	bool active;
	uint8_t num_keys;
	uint8_t num_layers;
	uint8_t cur_layer;
	/* last scancode sent by each key
	 * this is to make sure a scancode is released even if a key is
	 * released on a different layer */
	uint8_t *last_scancode;
};

typedef void (*scancode_callback_t)(uint8_t code, bool state);

int LAYOUT_init(int num_keys);
int LAYOUT_set(const struct layout *layout);
void LAYOUT_set_callback(scancode_callback_t callback);
void LAYOUT_set_key_state(uint8_t key, bool event);
void LAYOUT_deactivate();