/***************************************************************************************
 *
 *  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
 *
 *  By downloading, copying, installing or using the software you agree to this license.
 *  If you do not agree to this license, do not download, install, 
 *  copy or use the software.
 *
 *  Copyright (C) 2014-2024, Happytimesoft Corporation, all rights reserved.
 *
 *  Redistribution and use in binary forms, with or without modification, are permitted.
 *
 *  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 "sys_inc.h"
#include "aac_rtp_rx.h"
#include "bs.h"


BOOL aac_data_rx(AACRXI * p_rxi, uint8 * p_data, int len)
{
	struct AUHeader 
	{
		uint32 size;
		uint32 index; // indexDelta for the 2nd & subsequent headers
	};

	uint8* headerStart = p_data;
	uint32 packetSize = len;
	uint32 resultSpecialHeaderSize;

	uint32 fNumAUHeaders; // in the most recently read packet
  	struct AUHeader* fAUHeaders;

	// default values:
	resultSpecialHeaderSize = 0;
	fNumAUHeaders = 0;
	fAUHeaders = NULL;

	if (p_rxi->size_length == 0) 
	{
		return FALSE;
	}
	
	// The packet begins with a "AU Header Section".  Parse it, to
	// determine the "AU-header"s for each frame present in this packet
	resultSpecialHeaderSize += 2;
	if (packetSize < resultSpecialHeaderSize)
	{
		return FALSE;
	}

	uint32 AU_headers_length = (headerStart[0] << 8) | headerStart[1];
	uint32 AU_headers_length_bytes = (AU_headers_length + 7) / 8;
	if (packetSize < resultSpecialHeaderSize + AU_headers_length_bytes)
	{
		return FALSE;
	}
	resultSpecialHeaderSize += AU_headers_length_bytes;

	// Figure out how many AU-headers are present in the packet
	int bitsAvail = AU_headers_length - (p_rxi->size_length + p_rxi->index_length);
	if (bitsAvail >= 0 && (p_rxi->size_length + p_rxi->index_delta_length) > 0)
	{
		fNumAUHeaders = 1 + bitsAvail / (p_rxi->size_length + p_rxi->index_delta_length);
	}
	
	if (fNumAUHeaders > 0) 
	{
		fAUHeaders = new AUHeader[fNumAUHeaders];
		// Fill in each header:
        bs_t bs;
        bs_init(&bs, &headerStart[2], AU_headers_length);

        fAUHeaders[0].size = bs_read(&bs, p_rxi->size_length);
		fAUHeaders[0].index = bs_read(&bs, p_rxi->index_length);

		for (uint32 i = 1; i < fNumAUHeaders; ++i) 
		{
			fAUHeaders[i].size = bs_read(&bs, p_rxi->size_length);
			fAUHeaders[i].index = bs_read(&bs, p_rxi->index_delta_length);
		}
	}

	p_data += resultSpecialHeaderSize;
	len -= resultSpecialHeaderSize;
	
	if (fNumAUHeaders == 1 && (uint32) len < fAUHeaders[0].size) 
	{
		if (fAUHeaders[0].size > p_rxi->buf_len) 
		{
		    if (fAUHeaders)
        	{
        		delete[] fAUHeaders;
        	}
            	
            return FALSE;
        }

        memcpy(p_rxi->p_buf + p_rxi->d_offset, p_data, len);
		p_rxi->d_offset += len;

		if (p_rxi->rtprxi.rxf_marker)
		{
			if (p_rxi->d_offset != fAUHeaders[0].size) 
			{
			    if (fAUHeaders)
            	{
            		delete[] fAUHeaders;
            	}
	
				p_rxi->d_offset = 0;
				return FALSE;
			}

			if (p_rxi->pkt_func)
	  		{
	  			p_rxi->pkt_func(p_rxi->p_buf, p_rxi->d_offset, p_rxi->rtprxi.ts, p_rxi->rtprxi.seq, p_rxi->user_data);
	  		}
		}
	}
	else
	{
		for (uint32 i = 0; i < fNumAUHeaders; i++)
		{
			if ((uint32) len < fAUHeaders[i].size) 
			{
			    if (fAUHeaders)
            	{
            		delete[] fAUHeaders;
            	}
	
	    		return FALSE;
			}

			memcpy(p_rxi->p_buf, p_data, fAUHeaders[i].size);
			p_data += fAUHeaders[i].size;
			len -= fAUHeaders[i].size;

			if (p_rxi->pkt_func)
	  		{
	  			p_rxi->pkt_func(p_rxi->p_buf, fAUHeaders[i].size, p_rxi->rtprxi.ts, p_rxi->rtprxi.seq, p_rxi->user_data);
	  		}
		}
	}

	if (fAUHeaders)
	{
		delete[] fAUHeaders;
	}

	return TRUE;
}

BOOL aac_rtp_rx(AACRXI * p_rxi, uint8 * p_data, int len)
{
	if (p_rxi == NULL)
	{
		return FALSE;
	}
	
	if (!rtp_data_rx(&p_rxi->rtprxi, p_data, len))
	{
		return FALSE;
	}

	return aac_data_rx(p_rxi, p_rxi->rtprxi.p_data, p_rxi->rtprxi.len);
}

BOOL aac_rxi_init(AACRXI * p_rxi, VRTPRXCBF cbf, void * p_userdata)
{
	memset(p_rxi, 0, sizeof(AACRXI));

	p_rxi->buf_len = RTP_MAX_AUDIO_BUFF;
	
	p_rxi->p_buf_org = (uint8 *)malloc(p_rxi->buf_len);
	if (p_rxi->p_buf_org == NULL)
	{
		return FALSE;
    }
    
	p_rxi->p_buf = p_rxi->p_buf_org + 32;
	p_rxi->buf_len -= 32;
	p_rxi->pkt_func = cbf;
    p_rxi->user_data = p_userdata;

	return TRUE;
}

void aac_rxi_deinit(AACRXI * p_rxi)
{
	if (p_rxi->p_buf_org)
	{
		free(p_rxi->p_buf_org);
    }
    
	memset(p_rxi, 0, sizeof(AACRXI));
}