/*
 * $Id$
 *
    Copyright (c) 2015-2016 Chung, Hyung-Hwan. All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:
    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in the
       documentation and/or other materials provided with the distribution.

    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAfRRANTIES
    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


#include "stio-udp.h"
#include "stio-prv.h"

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>


static int udp_make (stio_dev_t* dev, void* ctx)
{
	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
	stio_dev_udp_make_t* arg = (stio_dev_udp_make_t*)ctx;
	stio_scklen_t len;
	stio_sckfam_t family;

	if (stio_getsckadrinfo(dev->stio, &arg->addr, &len, &family) <= -1) return -1;

	udp->sck = stio_openasyncsck (dev->stio, family, SOCK_DGRAM);
	if (udp->sck == STIO_SCKHND_INVALID) goto oops;

	/* some socket options? */
	if (bind (udp->sck, (struct sockaddr*)&arg->addr, len) == -1) 
	{
		udp->stio->errnum = stio_syserrtoerrnum(errno);
		goto oops;
	}

	udp->on_write = arg->on_write;
	udp->on_read = arg->on_read;
	return 0;

oops:
	if (udp->sck != STIO_SCKHND_INVALID)
	{
		stio_closeasyncsck (udp->stio, udp->sck);
		udp->sck = STIO_SCKHND_INVALID;
	}
	return -1;
}

static void udp_kill (stio_dev_t* dev)
{
	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
	if (udp->sck != STIO_SCKHND_INVALID) 
	{
		stio_closeasyncsck (udp->stio, udp->sck);
		udp->sck = STIO_SCKHND_INVALID;
	}
}

static stio_syshnd_t udp_getsyshnd (stio_dev_t* dev)
{
	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
	return (stio_syshnd_t)udp->sck;
}

static int udp_read (stio_dev_t* dev, void* buf, stio_len_t* len)
{
	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
	stio_scklen_t addrlen;
	int x;

/* TODO: udp_read need source address ... have to extend the send callback to accept the source address */
printf ("UDP RECVFROM...\n");
	addrlen = STIO_SIZEOF(udp->peer);
	x = recvfrom (udp->sck, buf, *len, 0, (struct sockaddr*)&udp->peer, &addrlen);
	if (x <= -1)
	{
		if (errno == EINPROGRESS || errno == EWOULDBLOCK) return 0;  /* no data available */
		if (errno == EINTR) return 0;
		udp->stio->errnum = stio_syserrtoerrnum(errno);
		return -1;
	}

	*len = x;
	return 1;
}

static int udp_write (stio_dev_t* dev, const void* data, stio_len_t* len)
{
	stio_dev_udp_t* udp = (stio_dev_udp_t*)udp;
	ssize_t x;

#if 0
/* TODO: udp_write need target address ... have to extend the send callback to accept the target address */
	x = sendto (udp->sck, data, *len, skad, stio_getskadlen(skad));
	if (x <= -1) 
	{
		if (errno == EINPROGRESS || errno == EWOULDBLOCK) return 0;  /* no data can be written */
		if (errno == EINTR) return 0;
		udp->stio->errnum = stio_syserrtoerrnum(errno);
		return -1;
	}

/* for UDP, if the data chunk can't be written at one go, it's actually a failure */
	if (x != *len) return -1; /* TODO: can i hava an indicator for this in stio? */

	*len = x;
#endif
	return 1;
}


static int udp_ioctl (stio_dev_t* dev, int cmd, void* arg)
{
	return 0;
}


/* ------------------------------------------------------------------------ */

static stio_dev_mth_t udp_mth = 
{
	udp_make,
	udp_kill,
	udp_getsyshnd,

	udp_read,
	udp_write,
	udp_ioctl,     /* ioctl */
};

static int udp_ready (stio_dev_t* dev, int events)
{
/* TODO: ... */
	if (events & STIO_DEV_EVENT_ERR) printf ("UDP READY ERROR.....\n");
	if (events & STIO_DEV_EVENT_HUP) printf ("UDP READY HANGUP.....\n");
	if (events & STIO_DEV_EVENT_PRI) printf ("UDP READY PRI.....\n");
	if (events & STIO_DEV_EVENT_IN) printf ("UDP READY IN.....\n");
	if (events & STIO_DEV_EVENT_OUT) printf ("UDP READY OUT.....\n");

	return 0;
}

static int udp_on_read (stio_dev_t* dev, const void* data, stio_len_t len)
{
printf ("dATA received %d bytes\n", (int)len);
	return 0;

}

static int udp_on_write (stio_dev_t* dev, stio_len_t wrlen, void* wrctx)
{
	return 0;

}

static stio_dev_evcb_t udp_evcb =
{
	udp_ready,
	udp_on_read,
	udp_on_write
};

stio_dev_udp_t* stio_dev_udp_make (stio_t* stio, stio_size_t xtnsize, const stio_dev_udp_make_t* data)
{
	return (stio_dev_udp_t*)stio_makedev (stio, STIO_SIZEOF(stio_dev_udp_t) + xtnsize, &udp_mth, &udp_evcb, (void*)data);
}