/*
 * Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
 * Copyright (c) 2002-2007, Professor Benoit Macq
 * Copyright (c) 2002-2003, Yannick Verschueren
 * Copyright (c) 2005, Herve Drolon, FreeImage Team
 * Copyright (c) 2008, Jerome Fimes, Communications & Systemes <jerome.fimes@c-s.fr>
 * 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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 "jpt.h"
#include "openjpeg.h"
#include "cio.h"
#include "event.h"
/*
 * Read the information contains in VBAS [JPP/JPT stream message header]
 * Store information (7 bits) in value
 * @param p_cio the stream to read from.
 * @param p_value the data to update
 * @return the nb of bytes read or -1 if an io error occurred.
 */
bool jpt_read_VBAS_info(opj_stream_private_t * p_cio, OPJ_UINT32 * p_nb_bytes_read, OPJ_UINT32 * p_value, opj_event_mgr_t * p_manager) 
{
	OPJ_BYTE l_elmt;
	OPJ_UINT32 l_nb_bytes_read = 0;
	
	// read data till the MSB of the current byte is 1.
	// concatenate 7 bits of data, last bit is finish flag

	// read data from the stream
	
	if
		(opj_stream_read_data(p_cio,&l_elmt,1,p_manager) != 1)
	{
		opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data.\n");
		return false;
	}
	++l_nb_bytes_read;

	// is the MSB equal to 1 ?
	while 
		(l_elmt & 0x80) 
	{
		// concatenate 7 bits of data, last bit is finish flag
		*p_value = (*p_value  << 7) | (l_elmt & 0x7f);
		if
			(opj_stream_read_data(p_cio,&l_elmt,1,p_manager) != 1)
		{
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data.\n");
			return false;
		}
		++l_nb_bytes_read;
	}
	// concatenate 7 bits of data, last bit is finish flag
	*p_value = (*p_value  << 7) | (l_elmt & 0x7f);
	* p_nb_bytes_read = l_nb_bytes_read;
	return true;
}

/*
 * Initialize the value of the message header structure 
 *
 */
void jpt_init_msg_header(opj_jpt_msg_header_t * header) 
{
	header->Id = 0;		/* In-class Identifier    */
	header->last_byte = 0;	/* Last byte information  */
	header->Class_Id = 0;		/* Class Identifier       */
	header->CSn_Id = 0;		/* CSn : index identifier */
	header->Msg_offset = 0;	/* Message offset         */
	header->Msg_length = 0;	/* Message length         */
	header->Layer_nb = 0;		/* Auxiliary for JPP case */
}

/*
 * Re-initialize the value of the message header structure
 *
 * Only parameters always present in message header
 *
 */
void jpt_reinit_msg_header(opj_jpt_msg_header_t * header) 
{
	header->Id = 0;		/* In-class Identifier    */
	header->last_byte = 0;	/* Last byte information  */
	header->Msg_offset = 0;	/* Message offset         */
	header->Msg_length = 0;	/* Message length         */
}

/*
 * Read the message header for a JPP/JPT - stream
 *
 */
bool jpt_read_msg_header(opj_stream_private_t *cio, opj_jpt_msg_header_t *header, OPJ_UINT32 * p_nb_bytes_read, opj_event_mgr_t * p_manager) 
{
	OPJ_BYTE elmt, Class = 0, CSn = 0;
	OPJ_UINT32 l_nb_bytes_read = 0;
	OPJ_UINT32 l_last_nb_bytes_read;


	jpt_reinit_msg_header(header);
	
	/* ------------- */
	/* VBAS : Bin-ID */
	/* ------------- */
	if
		(opj_stream_read_data(cio,&elmt,1,p_manager) != 1)
	{
		opj_event_msg(p_manager, EVT_ERROR, "Forbidden value encounter in message header !!\n");
		return false;
	}
	++l_nb_bytes_read;

	/* See for Class and CSn */
	switch ((elmt >> 5) & 0x03)
	{
		case 0:
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
			break;
		case 1:
			Class = 0;
			CSn = 0;
			break;
		case 2:
			Class = 1;
			CSn = 0;
			break;
		case 3:
			Class = 1;
			CSn = 1;
			break;
		default:
			break;
	}

	/* see information on bits 'c' [p 10 : A.2.1 general, ISO/IEC FCD 15444-9] */
	if 
		(((elmt >> 4) & 0x01) == 1)
	{
		header->last_byte = 1;
	}

	/* In-class identifier */
	header->Id |= (elmt & 0x0f);
	if 
		((elmt >> 7) == 1)
	{
		l_last_nb_bytes_read = 0;
		if
			(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->Id), p_manager))
		{
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
			return false;
		}
		l_nb_bytes_read += l_last_nb_bytes_read;
	}

	/* ------------ */
	/* VBAS : Class */
	/* ------------ */
	if (Class == 1) 
	{
		header->Class_Id = 0;
		l_last_nb_bytes_read = 0;
		if
			(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->Class_Id), p_manager))
		{
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
			return false;
		}
		l_nb_bytes_read += l_last_nb_bytes_read;
	}

	/* ---------- */
	/* VBAS : CSn */
	/* ---------- */
	if (CSn == 1) 
	{
		header->CSn_Id = 0;
		l_last_nb_bytes_read = 0;
		if
			(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->CSn_Id), p_manager))
		{
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
			return false;
		}
		l_nb_bytes_read += l_last_nb_bytes_read;
	}

	/* ----------------- */
	/* VBAS : Msg_offset */
	/* ----------------- */
	l_last_nb_bytes_read = 0;
	if
		(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->Msg_offset), p_manager))
	{
		opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
		return false;
	}
	l_nb_bytes_read += l_last_nb_bytes_read;

	/* ----------------- */
	/* VBAS : Msg_length */
	/* ----------------- */
	l_last_nb_bytes_read = 0;
	if
		(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->Msg_length), p_manager))
	{
		opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
		return false;
	}
	l_nb_bytes_read += l_last_nb_bytes_read;

	/* ---------- */
	/* VBAS : Aux */
	/* ---------- */
	if ((header->Class_Id & 0x01) == 1) 
	{
		header->Layer_nb = 0;
		if
			(! jpt_read_VBAS_info(cio, &l_last_nb_bytes_read, &(header->Layer_nb), p_manager))
		{
			opj_event_msg(p_manager, EVT_ERROR, "Error trying to read a byte of data!!!\n");
			return false;
		}
		l_nb_bytes_read += l_last_nb_bytes_read;
	}
	* p_nb_bytes_read = l_nb_bytes_read;
	return true;
}