/* Copyright (c) 2000-2019 Ericsson Telecom AB AB
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Michael Josenhans
******************************************************************************/
//
//  File:               Isobus.ttcn
//  Description:        Encoder / Decoder for Isobus message frames
//
// Revision R1A

module Isobus {
import from General_Types all
import from Can all
import from IsobusCMMessageTypes all
import from IsobusNMMessageTypes all
import from IsobusVTMessageTypes all

// Note:
// SocketCAN Error frames are not considered here
// SocketCAN RTR frames are not considered here
// SocketCAN Basic frames are not considered here

external function encode_CAN_frame_j1939mod(in CAN_frame_j1939mod pdu) return octetstring 
with { extension "prototype(convert) encode(RAW)" }
external function decode_CAN_frame_j1939mod(in octetstring data) return CAN_frame_j1939mod
with { extension "prototype(convert) decode(RAW)" }

const octetstring ISOBUS_PRIORITY_MASK    := '1C000000'O;
const octetstring ISOBUS_RESERVED_MASK    := '02000000'O;
const octetstring ISOBUS_DATAPAGE_MASK    := '01000000'O;
const octetstring ISOBUS_PDUFORMAT_MASK   := '00FF0000'O;
const octetstring ISOBUS_PDUSPECIFIC_MASK := '0000FF00'O;
const octetstring ISOBUS_SOURCEADDRESS_MASK := '000000FF'O;

//type BIT3 Priority 

type bitstring Priority length(6)
with {
  variant "ALIGN(left)";
  variant "FIELDLENGTH(6)"
}


type record J1939 { // Error & RTR Frames are not considered here
  //PGN   pgn optional,
  //BIT3           ignore,
  Priority       prio,
  BIT1           res, 
  BIT1           dp,
  OCT1           pf,
  OCT1           ps,
  SourceAddress  sa
} with { variant "FIELDORDER(msb)" }


type record J1939mod { // Error & RTR Frames are not considered here
  //PGN   pgn optional,
  //BIT3           ignore,
  Priority       prio,
  BIT1           res, 
  BIT1           dp,
  OCT1           pf,
  OCT1           ps,
  SourceAddress  sa,
  OCT3           comp
} with { variant "FIELDORDER(msb)" }


type union AnyIsoBusPdu {
  ETP_DT                     etp_dt,  // extended TP data transfer
  ETP_CM                     etp_cm,  // extended TP connection management 
  VT2ECU                     vt2ecu,  // Message Virtual Terminal (VT) to ECU
  ECU2VT                     ecu2vt,  // Message ECU to Virtual Terminal (VT)
  RequestForAddressClaimed   requestForAddressClaimed,
  TP_DT                      tp_dt,   // TP data transfer
  TP_CM                      tp_cm,   // TP connection management
  NetworkMessage             networkMessage, // Network Message according ISO 11873-4
  CannotClaimSourceAddress   cannotClaimSourceAddress,
  AddressClaimed             addressClaimed,
  CommandedAddress           commandedAddress
  // other upper layer isobus protocols like Task Comtroller are added here ...
}
with { variant "" }

type record CAN_frame_j1939 {
  J1939               can_j1939,
  AnyIsoBusPdu        can_pdu 
}with { variant "" }


type record CAN_frame_j1939mod {
  J1939mod            can_j1939,
  AnyIsoBusPdu        can_pdu 
}with {
  variant (can_pdu) "CROSSTAG(
  etp_dt,                   can_j1939.comp = 'C70000'O;  //199
  etp_cm,                   can_j1939.comp = 'C80000'O;  //200
  vt2ecu,                   can_j1939.comp = 'E60000'O;  //230
  ecu2vt,                   can_j1939.comp = 'E70000'O;  //231
  requestForAddressClaimed, can_j1939.comp = 'EA0000'O;  //234
  tp_dt,                    can_j1939.comp = 'EB0000'O;  //235
  tp_cm,                    can_j1939.comp = 'EC0000'O;  //236
  networkMessage,           can_j1939.comp = 'ED0000'O;  //237
  cannotClaimSourceAddress, can_j1939.comp = 'EEFFFE'O;  //238 all and conjuction needed!!!!!!
  addressClaimed,           can_j1939.comp = 'EEFF00'O;  //238 all and conjuction needed!!!!!!
  commandedAddress,         can_j1939.comp = 'FED800'O)" //254 all and conjuction needed!!!!!!
}

function j1939frame2can(in CAN_frame_j1939 p_can_frame_j1939, in Priority p_priority, in DestinationAddress p_da, in SourceAddress p_sa) return CAN_frame {
  var CAN_frame v_can_frame
  v_can_frame.can_id := pdu1_j1939id2canid(p_can_frame_j1939.can_j1939, p_priority, p_da, p_sa)
  // v_can_frame.can_pdu := encode_AnyIsoBusPdu(p_can_frame_j1939.can_pdu)
  v_can_frame.can_pdu := substr(f_encode_CAN_frame_j1939(p_can_frame_j1939),0,3)//strip 3 byte header 
  return v_can_frame
}

function pdu1_j1939id2canid(in J1939 p_j1939, in Priority p_priority, in DestinationAddress p_da, in SourceAddress p_sa) return CAN_id{
  var CAN_id v_can_id
  v_can_id := bit2oct(oct2bit(p_sa) or4b (oct2bit(p_da) << 8) or4b (oct2bit(p_j1939.pf) << 16) or4b ((p_j1939.dp) << 24) or4b 
    ((p_j1939.res) << 25) or4b (int2bit(bit2int(p_priority), 32) << 26))
  return v_can_id
}

/*
function j1939id2canid(in J1939 p_j1939) return CAN_id{
var CAN_id v_can_id
v_can_id := (p_j1939.sa << 0) or4b (p_j1939.ps << 8) or4b (p_j1939.pf << 16) or4b bit2oct(p_j1939.dp << 24) or4b 
bit2oct(p_j1939.res << 25) or4b bit2oct(p_j1939.prio << 26)
return v_can_id
}
*/

function j1939id2canid(in J1939 p_j1939) return CAN_id{
  var CAN_id v_can_id
  v_can_id := int2oct(
    oct2int(p_j1939.sa) + oct2int(p_j1939.ps)*256 + oct2int(p_j1939.pf) * 256 * 256 + 
    bit2int(p_j1939.dp) * 256 * 256 * 256 + bit2int(p_j1939.res) * 256 * 256 * 256 * 2 + 
    bit2int(p_j1939.prio) * 256 * 256 * 256 * 2 * 2, 
    4 )
  return v_can_id
}

//---------------------------------------------------------------------------------------
function can2j1939frame(CAN_frame p_can_frame) return CAN_frame_j1939 {
  //--------------------------------------------------------------------------------------- 
  var CAN_frame_j1939 v_can_frame_j1939

  //log("can_id", p_can_frame.can_id)  
  //log("can_pdu", p_can_frame.can_pdu)

  v_can_frame_j1939:=f_decode_CAN_frame_j1939(p_can_frame.can_id& p_can_frame.can_pdu)

  //log("Higher layer octet pdustring: ", v_can_frame_j1939)
  return v_can_frame_j1939
}

function canid2j1939(in CAN_id p_can_id) return J1939 {
  //--------------------------------------------------------------------------------------- 

  var bitstring v_can_id_bitstring:= oct2bit(p_can_id)
  var J1939 v_j1939

  v_j1939.prio :=substr(v_can_id_bitstring, 0, 6); //3 ,3
  v_j1939.res  :=v_can_id_bitstring[6];
  v_j1939.dp   :=v_can_id_bitstring[7];
  v_j1939.pf   :=p_can_id[1];//(p_can_id and4b ISOBUS_PDUFORMAT_MASK) >> 2   // shift 16 bits = 2 octets
  v_j1939.ps   :=p_can_id[2];// (p_can_id and4b ISOBUS_PDUSPECIFIC_MASK) >> 1 // shift  8 bits = 1 octet
  v_j1939.sa   :=p_can_id[3];//(p_can_id and4b ISOBUS_SOURCEADDRESS_MASK)

  return v_j1939
}

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


//---------------------------------------------------------------------------
function f_insert_aux_hdr(in octetstring p_os) return octetstring
//---------------------------------------------------------------------------
{
  var OCT3 v_os


  v_os[0]:=p_os[1];//pf
  if(p_os[1] == 'FE'O)
  {
    if (p_os[2]=='D8'O) {v_os[1]:='D8'O;v_os[2]:='00'O;}
  }

  else if(p_os[1] == 'EE'O)
  {
    if (p_os[2] == 'FF'O) 
    { if (p_os[3]=='FE'O) {v_os[1]:='FF'O;v_os[2]:='FE'O;}
      else                  {v_os[1]:='FF'O;v_os[2]:='00'O;}
    }

  } 


  else  { v_os[1]:='00'O;v_os[2]:='00'O;}


  //log("replace(p_os,4,0,v_os)  :",replace(p_os,4,0,v_os))

  return replace(p_os,4,0,v_os)//insert aux header
}

//---------------------------------------------------------------------------
function f_remove_aux_hdr(in octetstring p_os) return octetstring
//---------------------------------------------------------------------------
{
  //log("p_os  :",p_os)


  p_os[1]:=p_os[4]; //pf := aux[0];
  if (p_os[4] == 'EE'O)  
  {
    if (p_os[6] == 'FE'O ) { //'EEFFFE' O
      p_os[2]:=p_os[5]; //ps := aux[1];
      p_os[3]:=p_os[6]; //sa := aux[2];
    }
    else    { //'EEFFXX'O
      p_os[2]:=p_os[5]; //ps := aux[1];
    }
  } 
  else  if  (p_os[4] == 'FE'O) //'FED8XX'O
  {
    p_os[2]:=p_os[5]; //ps := aux[1];
  }


  //log("p_os  :",p_os)

  //log("replace(p_os,4,3,''O)   :",replace(p_os,4,3,''O))
  return replace(p_os,4,3,''O); //remove aux header
}

//---------------------------------------------------------------------------
function f_map_mod2frame(in CAN_frame_j1939mod p_frame) return CAN_frame_j1939
//---------------------------------------------------------------------------
{
  var CAN_frame_j1939 v_CAN_frame_j1939

  v_CAN_frame_j1939.can_pdu:=p_frame.can_pdu;
  v_CAN_frame_j1939.can_j1939.prio:=p_frame.can_j1939.prio;
  v_CAN_frame_j1939.can_j1939.res:=p_frame.can_j1939.res;
  v_CAN_frame_j1939.can_j1939.dp:=p_frame.can_j1939.dp;
  v_CAN_frame_j1939.can_j1939.pf:=p_frame.can_j1939.pf;
  v_CAN_frame_j1939.can_j1939.ps:=p_frame.can_j1939.ps;
  v_CAN_frame_j1939.can_j1939.sa:=p_frame.can_j1939.sa;


  //log("v_CAN_frame_j1939   :",v_CAN_frame_j1939)
  return v_CAN_frame_j1939

}


//---------------------------------------------------------------------------
function f_map_frame2mod(in CAN_frame_j1939 p_frame) return CAN_frame_j1939mod
//---------------------------------------------------------------------------
{
  var CAN_frame_j1939mod v_CAN_frame_j1939mod


  v_CAN_frame_j1939mod.can_pdu:=p_frame.can_pdu;
  v_CAN_frame_j1939mod.can_j1939.prio:=p_frame.can_j1939.prio;
  v_CAN_frame_j1939mod.can_j1939.res:=p_frame.can_j1939.res;
  v_CAN_frame_j1939mod.can_j1939.dp:=p_frame.can_j1939.dp;
  v_CAN_frame_j1939mod.can_j1939.pf:=p_frame.can_j1939.pf;
  v_CAN_frame_j1939mod.can_j1939.ps:=p_frame.can_j1939.ps;
  v_CAN_frame_j1939mod.can_j1939.sa:=p_frame.can_j1939.sa;
  if (p_frame.can_j1939.pf == 'EE'O)
  {
    if (p_frame.can_j1939.ps == 'D8'O)  { 
      v_CAN_frame_j1939mod.can_j1939.comp := p_frame.can_j1939.pf&p_frame.can_j1939.ps&'00'O;
    } else if (p_frame.can_j1939.ps == 'FF'O) {
      if (p_frame.can_j1939.sa == 'FE'O) {
        v_CAN_frame_j1939mod.can_j1939.comp := p_frame.can_j1939.pf&p_frame.can_j1939.ps&p_frame.can_j1939.sa
      } else {//??
        v_CAN_frame_j1939mod.can_j1939.comp:=p_frame.can_j1939.pf&'0000'O;
      }
    } else {//?? 
      v_CAN_frame_j1939mod.can_j1939.comp:=p_frame.can_j1939.pf&'0000'O;
    } 
  } else {
    v_CAN_frame_j1939mod.can_j1939.comp := p_frame.can_j1939.pf&'0000'O;
  }
  //log("v_CAN_frame_j1939mod  :",v_CAN_frame_j1939mod)
  return v_CAN_frame_j1939mod;
}


//---------------------------------------------------------------------------
function f_encode_CAN_frame_j1939(in CAN_frame_j1939 pdu) return octetstring 
//---------------------------------------------------------------------------
{

  return f_remove_aux_hdr(encode_CAN_frame_j1939mod(f_map_frame2mod(pdu)))


}
//---------------------------------------------------------------------------
function f_decode_CAN_frame_j1939(in octetstring data) return CAN_frame_j1939
//---------------------------------------------------------------------------
{
  log("f_insert_aux_hdr(data)", f_insert_aux_hdr(data));
  return f_map_mod2frame(decode_CAN_frame_j1939mod(f_insert_aux_hdr(data)))


}


} with { encode "RAW" }