/**
 * \file
 *
 * \author	Georg Hopp
 *
 * \copyright
 * Copyright © 2014 Georg Hopp
 *
 * 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/>.
 */

#include <unistd.h>
#include <inttypes.h>
#include <stdio.h>

#include "trbase.h"
#include "trevent.h"
#include "trio.h"

#include "tr/io_handler.h"
#include "tr/comm_end_point.h"
#include "tr/interface/comm_end_point.h"

static
int
ioHandlerCtor(void * _this, va_list * params)
{
	TR_PARENTCALL(TR_IoHandler, _this, TR_Class, ctor, params);

	return 0;
}

static void ioHandlerDtor(void * _this) {}

static
TR_EventDone
ioHandlerRead(void * _this, TR_Event event)
{
	TR_CommEndPoint endpoint = (TR_CommEndPoint)event->subject;
	TR_Event        revent;
	TR_RemoteData   data;

	switch (TR_commEndPointRead(endpoint, &data)) {
		case FALSE: // EAGAIN
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_READ_BLOCK,
					NULL);
			break;

		case -1: // error
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_CLOSE,
					NULL);
			break;

		default:
		case -2: // remote close
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_SHUT_READ,
					NULL);
			break;

		case -3: // read limit
			return TR_EVENT_DONE;

		case TRUE:
			if (event->subject->fin) {
				TR_delete(data);
				return TR_EVENT_DONE;
			}

			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_NEW_DATA,
					data);
			break;
	}

	TR_eventHandlerIssueEvent((TR_EventHandler)_this, revent);

	return TR_EVENT_DONE;
}

static
TR_EventDone
ioHandlerWrite(void * _this, TR_Event event)
{
	TR_Event        revent   = NULL;
	TR_CommEndPoint endpoint = (TR_CommEndPoint)event->subject;
	size_t          written;

	switch (TR_cepWriteBuffered(endpoint, &written)) {
		case FALSE: // EAGAIN
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_WRITE_BLOCK,
					NULL);
			break;

		case -1:    // FAILURE
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_CLOSE,
					NULL);
			break;

		case -2:    // remote close
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_SHUT_WRITE,
					NULL);
			break;

		case -3:    // remote end not ready
			break;

		case -4:	// no more data to send
			revent = TR_eventSubjectEmit(
					event->subject,
					TR_CEP_EVENT_DATA_END,
					NULL);
			break;

		default:
			// TODO This still looks wrong...
			if (TRUE == endpoint->do_close) {
				revent = TR_eventSubjectEmit(
						event->subject,
						TR_CEP_EVENT_CLOSE,
						NULL);
			}
	}

	endpoint->write_buffer_size -= written;

	if (revent) {
		TR_eventHandlerIssueEvent((TR_EventHandler)_this, revent);
	}

	return TR_EVENT_DONE;
}

static
void
ioHandlerCvInit(TR_class_ptr cls)
{
	TR_EVENT_HANDLER_SET_METHOD(
			cls,
			TR_CommEndPoint,
			TR_CEP_EVENT_DO_READ,
			ioHandlerRead);
	TR_EVENT_HANDLER_SET_METHOD(
			cls,
			TR_CommEndPoint,
			TR_CEP_EVENT_DO_WRITE,
			ioHandlerWrite);
}

TR_INIT_HANDLER(TR_IoHandler);
TR_INIT_IFACE(TR_Class, ioHandlerCtor, ioHandlerDtor, NULL);
TR_CREATE_CLASS(
		TR_IoHandler,
		TR_EventHandler,
		ioHandlerCvInit,
		TR_IF(TR_Class)) = {
	{ TR_HANDLER_CVARS(TR_IoHandler) }
};

// vim: set ts=4 sw=4: