#include<stdio.h>
#include<stdlib.h>
#include<stdint.h>

#include "TLVEncoder.h"
#include "TLVDecoder.h"
#include "EPSNASMessageContainer.h"

int encode_epsnas_message_container ( EPSNASMessageContainer epsnasmessagecontainer, uint8_t iei, uint8_t * buffer, uint32_t len  ) 
{
    uint8_t *lenPtr;
    uint32_t encoded = 0;
    int encode_result;
    CHECK_PDU_POINTER_AND_LENGTH_ENCODER (buffer,EPSNAS_MESSAGE_CONTAINER_MINIMUM_LENGTH , len);
    
    if( iei >0  ){
      *buffer=iei;
      encoded++;
    }

    lenPtr = (buffer + encoded);
    encoded++;
    encoded++;

    if ((encode_result = encode_bstring (epsnasmessagecontainer, buffer + encoded, len - encoded)) < 0)//加密,实体,首地址,长度
        return encode_result;
    else
        encoded += encode_result;

    uint32_t res = encoded - 2 - ((iei > 0) ? 1 : 0);
    *lenPtr =res/(1<<8);
    lenPtr++;
    *lenPtr = res%(1<<8);

    return encoded;
}

int decode_epsnas_message_container ( EPSNASMessageContainer * epsnasmessagecontainer, uint8_t iei, uint8_t * buffer, uint32_t len  ) 
{
    int decoded=0;
    uint8_t ielen=0;
    int decode_result;

    if (iei > 0)
    {
        CHECK_IEI_DECODER (iei, *buffer);
        decoded++;
    }

    ielen = *(buffer + decoded);
    decoded++;
    ielen = ( ielen << 8)+*(buffer + decoded);
    decoded++;
    CHECK_LENGTH_DECODER (len - decoded, ielen);

    if((decode_result = decode_bstring (epsnasmessagecontainer, ielen, buffer + decoded, len - decoded)) < 0)
        return decode_result;
    else
        decoded += decode_result;
    return decoded;
}

