/*****************************************************************************
 *
 * grail - Gesture Recognition And Instantiation Library
 *
 * Copyright (C) 2010 Canonical Ltd.
 *
 * This program 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 3 of the License, or (at your
 * option) any later version.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Authors:
 *      Henrik Rydberg <rydberg@bitmath.org>
 *
 ****************************************************************************/

#include <grail-gesture.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>

struct gesture_handler {
	struct touch_frame frame;
	struct gesture_client client;
	struct gesture_dev dev;
	touch_time_t last_scroll;
};

static void gh_gesture(struct gesture_client *client,
		       const struct gesture_event *ev)
{
	int i;
	fprintf(stderr, "gesture %d %lld\n",
		ev->type, ev->time);
	switch (ev->type) {
	case GE_MOVE:
		fprintf(stderr, "  %d\n", ev->prop[0]);
		fprintf(stderr, "  %d\n", ev->prop[1]);
		break;
	case GE_VSCROLL:
		fprintf(stderr, "  %d\n", ev->prop[0]);
		break;
	}
}

static void gh_init(struct gesture_handler *gh)
{
	memset(gh, 0, sizeof(*gh));
	gedev_init(&gh->dev, 0);
	client_init(&gh->client, gh);
	gh->client.gesture = gh_gesture;
	gh->client.priority[GE_MOVE] = 1;
	gh->client.priority[GE_VSCROLL] = 2;
	gedev_attach_client(&gh->dev, &gh->client);
}

static void gh_handle(struct gesture_handler *gh,
		      const struct touch_frame *frame,
		      touch_time_t time)
{
	struct gesture_flag flag;
	struct gesture_event ev;
	if (frame->ntouch == 1 || frame->ntouch == 2) {
		flag.type = GE_MOVE;
		flag.time = time;
		flag.state = GS_BEGIN;
		gedev_flag(&gh->dev, &flag);

		ev.type = GE_MOVE;
		ev.time = time;
		ev.prop[0] =
			frame->touch[0].prop[TP_POS_X] -
			gh->frame.touch[0].prop[TP_POS_X];
		ev.prop[1] =
			frame->touch[0].prop[TP_POS_Y] -
			gh->frame.touch[0].prop[TP_POS_Y];
		if (ev.prop[0] || ev.prop[1])
			gedev_event(&gh->dev, &ev);

		flag.time = time + 1;
		flag.state = GS_END;
		gedev_flag(&gh->dev, &flag);
	}
	if (frame->ntouch == 2) {
		flag.type = GE_VSCROLL;
		flag.time = time;
		flag.state = GS_BEGIN;
		gedev_flag(&gh->dev, &flag);

		ev.type = GE_VSCROLL;
		ev.time = time;
		ev.prop[0] =
			frame->touch[0].prop[TP_POS_Y] -
			gh->frame.touch[0].prop[TP_POS_Y];

		if (ev.prop[0])
			gedev_event(&gh->dev, &ev);

		if (time > gh->last_scroll + 100) {
			flag.time = time + 1;
			flag.state = GS_END;
			gedev_flag(&gh->dev, &flag);
			gh->last_scroll = time;
		}
	} else {
		flag.type = GE_VSCROLL;
		flag.time = time;
		flag.state = GS_CANCEL;
		gedev_flag(&gh->dev, &flag);
	}
	gedev_sync(&gh->dev);
	gh->frame = *frame;
}

static void gh_destroy(struct gesture_handler *gh)
{
	gedev_detach_client(&gh->dev, &gh->client);
	client_destroy(&gh->client);
	gedev_destroy(&gh->dev);
}

static void tp_event(struct touch_engine *engine,
		     const struct input_event *ev)
{
}

static void tp_sync(struct touch_engine *engine,
		    const struct input_event *syn)
{
	struct gesture_handler *gh = engine->priv;
	struct touch_frame *frame = &engine->frame;
	gh_handle(gh, frame, frame->time);
}

static void loop_device(struct touch_dev *dev, int fd)
{
	struct gesture_handler gh;
	struct touch_engine engine;
	gh_init(&gh);
	touch_engine_init(&engine, tp_event, tp_sync, &gh);
	touch_engine_attach(&engine, dev);
	while (!touch_dev_idle(dev, fd, 5000))
		touch_dev_pull(dev, fd);
	touch_engine_detach(&engine, dev);
	gh_destroy(&gh);
}

int main(int argc, char *argv[])
{
	struct touch_dev dev;
	int fd;
	if (argc < 2) {
		fprintf(stderr, "Usage: %s <device>\n", argv[0]);
		return -1;
	}
	fd = open(argv[1], O_RDONLY | O_NONBLOCK);
	if (fd < 0) {
		fprintf(stderr, "error: could not open device\n");
		return -1;
	}
	if (ioctl(fd, EVIOCGRAB, 1)) {
		fprintf(stderr, "error: could not grab the device\n");
		return -1;
	}
	if (touch_dev_open(&dev, fd)) {
		fprintf(stderr, "error: could not open touch device\n");
		return -1;
	}
	loop_device(&dev, fd);
	touch_dev_close(&dev, fd);
	ioctl(fd, EVIOCGRAB, 0);
	close(fd);
	return 0;
}