/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * X11 Input
 *
 * Copyright 2013 Corey Clayton <can.of.tuna@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <math.h>

#include "xf_input.h"

#define MAX_CONTACTS 2

typedef struct touch_contact
{
	int id;
	int count;
	double pos_x;
	double pos_y;
	double last_x;
	double last_y;

} touchContact;

touchContact contacts[MAX_CONTACTS];

int active_contacts;

int xinput_opcode; //TODO: use this instead of xfi

void xf_input_init(xfInfo* xfi)
{
	int opcode, event, error;
	int major = 2, minor = 2;


	XIEventMask eventmask;
	unsigned char mask[(XI_LASTEVENT + 7)/8];

	active_contacts = 0;
	ZeroMemory(contacts, sizeof(touchContact) * MAX_CONTACTS);

	ZeroMemory(mask, sizeof(mask));


	if (XQueryExtension(xfi->display, "XInputExtension", &opcode, &event, &error))
	{

		xfi->XInputOpcode = opcode;

		XIQueryVersion(xfi->display, &major, &minor);
		if (!(major * 1000 + minor < 2002))
		{

			eventmask.deviceid = XIAllDevices;
			eventmask.mask_len = sizeof(mask);
			eventmask.mask = mask;

			XISetMask(mask, XI_TouchBegin);
			XISetMask(mask, XI_TouchUpdate);
			XISetMask(mask, XI_TouchEnd);

			error = XISelectEvents(xfi->display, xfi->window->handle, &eventmask, 1);

			switch (error)
			{
			case BadValue:
				printf("\tBadValue\n");
				break;
			case BadWindow:
				printf("\tBadWindow\n");
				break;

			case 0: //no error
				break;

			default:
				printf("XISelectEvents() returned %d\n", error);
				break;

			}

		}
		else
		{
			printf("Server does not support XI 2.2\n");
		}
	}
	else
	{
		printf("X Input extension not available!!!\n");
	}
}

void xf_input_handle_event(xfInfo* xfi, XEvent* event)
{
	//handle touch events
	XGenericEventCookie* cookie = &event->xcookie;

	XGetEventData(xfi->display, cookie);

	if (	(cookie->type == GenericEvent) &&
			(cookie->extension == xfi->XInputOpcode) )
		{
			switch(cookie->evtype)
			{
				case XI_TouchBegin:
					xf_input_touch_begin(xfi, cookie->data);
					break;

				case XI_TouchUpdate:
					xf_input_touch_update(xfi, cookie->data);
					break;

				case XI_TouchEnd:
					xf_input_touch_end(xfi, cookie->data);
					break;

				default:
					printf("unhandled xi type= %d\n", cookie->evtype);
					break;
			}
		}


	XFreeEventData(xfi->display,cookie);
}

void xf_input_touch_begin(xfInfo* xfi, XIDeviceEvent* event)
{
	int i;

	//find an empty slot and save it
	for(i=0; i<MAX_CONTACTS; i++)
	{
		if(contacts[i].id == 0)
		{
			contacts[i].id = event->detail;
			contacts[i].count = 1;
			contacts[i].pos_x = event->event_x;
			contacts[i].pos_y = event->event_y;

			active_contacts++;
			break;
		}
	}


	////
	printf("\tTouchBegin (%d)  [%.2f,%.2f]\n",
								event->detail,
								event->event_x,
								event->event_y);

}
void xf_input_touch_update(xfInfo* xfi, XIDeviceEvent* event)
{
	int i;


	for(i=0; i<MAX_CONTACTS; i++)
		{
			if(contacts[i].id == event->detail)
			{
				contacts[i].count++;
				contacts[i].last_x = contacts[i].pos_x;
				contacts[i].last_y = contacts[i].pos_y;
				contacts[i].pos_x = event->event_x;
				contacts[i].pos_y = event->event_y;

				//detect pinch-zoom
				if(active_contacts == 2)
				{
					int j = 0;

					//find the other nonzero contact
					for(j=0; j<MAX_CONTACTS; j++)
					{
						if( (contacts[j].id != 0) && (contacts[j].id != contacts[i].id) )
						{
							double delta;
							//now compute the delta
							delta = sqrt(pow(contacts[j].pos_x - contacts[i].last_x, 2.0) +
									pow(contacts[j].pos_y - contacts[i].last_y, 2.0));

							printf("delta = %.2f\n", delta);

							break;
						}
					}
				}

				break;
			}
		}


	printf("\tTouchUpdate (%d)  [%.2f,%.2f]\n",
								event->detail,
								event->event_x,
								event->event_y);
}
void xf_input_touch_end(xfInfo* xfi, XIDeviceEvent* event)
{
	int i;

	//find our and delete the point
	for(i=0; i<MAX_CONTACTS; i++)
		{
			if(contacts[i].id == event->detail)
			{
				contacts[i].id = 0;
				contacts[i].count = 0;
				//contacts[i].pos_x = (int)event->event_x;
				//contacts[i].pos_y = (int)event->event_y;

				active_contacts--;
				break;
			}
		}




	printf("\tTouchEnd (%d)  [%.2f,%.2f]\n",
								event->detail,
								event->event_x,
								event->event_y);
}