/*************************************************************************
* (C) 2010 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
*  by Michael Pounov <misho@openbsd-bg.org>
*
* $Author: misho $
* $Id: get.c,v 1.3 2012/07/22 22:21:50 misho Exp $
*
**************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
	by Michael Pounov <misho@elwix.org>.  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.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS 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 "global.h"


/*
 * pelco_GetVersion() Return Pelco protocol version
 * @p = Packet structure
 * return: 'd' - PelcoD, 'p' - PelcoP, 0 - unknown or bad packet
 */
inline u_char
pelco_GetVersion(void * __restrict p)
{
	u_char *ptr = (u_char *) p;

	if (!p || !*ptr) {
		pelcoSetErr(EINVAL, "invalid argument!\n");
		return 0;
	}

	switch (*ptr) {
		case VER_D_SYNC:
			return 'd';
		case VER_P_STX:
			if (VER_P_ETX == ptr[6])
				return 'p';
			pelcoSetErr(ENOEXEC, "broken Pelco P packet ...\n");
			break;
		default:
			pelcoSetErr(ENOEXEC, "unsupported Pelco protocol version!\n");
	}

	return 0;
}

/*
 * pelco_GetCamNo() Get Camera number and check for valid packet
 * @p = Packet structure
 * return: 0xFF and pelco_GetErrno() == ENOEXEC - error, 
 	any number is camera address
 */
inline u_char
pelco_GetCamNo(void * __restrict p)
{
	u_char ver;
	u_char *ptr = (u_char *) p;

	if (!p || !*ptr) {
		pelcoSetErr(EINVAL, "invalid argument!\n");
		return 0;
	}

	ver = pelco_GetVersion(p);
	switch (ver) {
		case 'd':
			if (crcPelco(ver, p) == ptr[6])
				return ptr[1];

			pelcoSetErr(ENOEXEC, "broken Pelco D packet!!!\n");
			break;
		case 'p':
			if (crcPelco(ver, p) == ptr[7])
				return ptr[1] + 1;

			pelcoSetErr(ENOEXEC, "broken Pelco P packet!!!\n");
			break;
	}

	return 0xFF;
}

/*
 * pelco_GetCamCmdData() Get from Camera commands and datas with verify packet
 * @p = Input Packet structure
 * @cam = Output camera number
 * @cmd[2] = Output Commands 1 & 2
 * @data[2] = Output Data for commands 1 & 2
 * return: 'd' - PelcoD, 'p' - PelcoP, 0 - unknown or bad packet
 */
inline u_char
pelco_GetCamCmdData(void * __restrict p, u_char * __restrict cam, 
		u_char * __restrict cmd, u_char * __restrict data)
{
	u_char ret;
	u_char *ptr = (u_char *) p;

	if (!p || !*ptr) {
		pelcoSetErr(EINVAL, "invalid argument!\n");
		return 0;
	}

	ret = pelco_GetVersion(p);
	switch (ret) {
		case 'd':
			if (crcPelco(ret, p) != ptr[6]) {
				pelcoSetErr(ENOEXEC, "broken Pelco D packet!!!\n");
				return 0;
			}

			if (cam)
				*cam = ptr[1];
			break;
		case 'p':
			if (crcPelco(ret, p) != ptr[7]) {
				pelcoSetErr(ENOEXEC, "broken Pelco P packet!!!\n");
				return 0;
			}

			if (cam)
				*cam = ptr[1] + 1;
			break;
	}

	if (cmd)
		memcpy(cmd, ptr + 2, 2);
	if (data)
		memcpy(data, ptr + 4, 2);
	return ret;
}

/*
 * pelco_D_toCmd() Convert to Pelco D commands
 * @cmd[2] = Input Commands 1 & 2
 * @cmd1 = Output typecasted commands 1
 * @cmd2 = Output typecasted commands 2
 * return: 0xFF - error, !=0 return number arguments
 */
inline u_char
pelco_D_toCmd(u_char * __restrict cmd, struct bitD_Cmd1 * __restrict cmd1, 
		struct bitD_Cmd2 * __restrict cmd2)
{
	u_char ret = 0;

	if (!cmd) {
		pelcoSetErr(EINVAL, "invalid argument!\n");
		return 0xFF;
	}

	if (cmd1) {
		cmd1 = (struct bitD_Cmd1*) &cmd[0];
		ret++;
	}
	if (cmd2) {
		cmd2 = (struct bitD_Cmd2*) &cmd[1];
		ret++;
	}

	return ret;
}

/*
 * pelco_P_toCmd() Convert to Pelco P commands
 * @cmd[2] = Input Commands 1 & 2
 * @cmd1 = Output typecasted commands 1
 * @cmd2 = Output typecasted commands 2
 * return: 0xFF - error, !=0 return number arguments
 */
inline u_char
pelco_P_toCmd(u_char * __restrict cmd, struct bitP_Cmd1 * __restrict cmd1, 
		struct bitP_Cmd2 * __restrict cmd2)
{
	u_char ret = 0;

	if (!cmd) {
		pelcoSetErr(EINVAL, "invalid argument!\n");
		return 0xFF;
	}

	if (cmd1) {
		cmd1 = (struct bitP_Cmd1*) &cmd[0];
		ret++;
	}
	if (cmd2) {
		cmd2 = (struct bitP_Cmd2*) &cmd[1];
		ret++;
	}

	return ret;
}