/*
  Copyright 2003-2004 Ronald S. Burkey <info@sandroid.org>
  
  This file is part of yaAGC. 

  yaAGC is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  yaAGC is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with yaAGC; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  Filename:     ParseGENADR.c
  Purpose:      Assembles the GENADR, ADDRES, and REMADR pseudo-ops.
  Mod History:  04/19/03 RSB   Began.
                04/27/03 RSB   The earlier versions were completely 
                               inadequate, because yaYUL didn't model
                               memory properly.  yaYUL has now been
                               substantially changed to account for this.
                07/21/04 RSB   Now allow constants as destinations.
*/

#include "yaYUL.h"
#include <stdlib.h>
#include <math.h>
#include <string.h>

//-------------------------------------------------------------------------
// Returns non-zero on unrecoverable error.

int
ParseGENADR(ParseInput_t *InRecord, ParseOutput_t *OutRecord)
{
  Address_t Address;
  int Value, i;

  IncPc(&InRecord->ProgramCounter, 1, &OutRecord->ProgramCounter);

  if (!OutRecord->ProgramCounter.Invalid && OutRecord->ProgramCounter.Overflow)
    {
      strcpy(OutRecord->ErrorMessage, "Next code may overflow storage.");
      OutRecord->Warning = 1;
    }

  OutRecord->EBank = InRecord->EBank;
  OutRecord->SBank = InRecord->SBank;
  OutRecord->NumWords = 1;

  if (InRecord->Extend && !InRecord->IndexValid)
    {
      strcpy(OutRecord->ErrorMessage, "Illegally preceded by EXTEND.");
      OutRecord->Fatal = 1;
      OutRecord->Extend = 0;
    }

  if (InRecord->IndexValid)
    {
      strcpy(OutRecord->ErrorMessage, "Illegally preceded by INDEX.");
      OutRecord->Fatal = 1;
      OutRecord->IndexValid = 0;
    }

  i = GetOctOrDec(InRecord->Operand, &Value);
  if (!i && *InRecord->Mod1 == 0)
    {
      IncPc(&InRecord->ProgramCounter, Value, &Address);

    DoIt:  
      if (Address.Invalid)
        {
          strcpy(OutRecord->ErrorMessage, "Destination address not resolved.");
          OutRecord->Fatal = 1;
          return (0);
        }

      if (Address.Constant)
          PseudoToStruct(Address.Value, &Address);

      if (!Address.Address)
        {
          strcpy(OutRecord->ErrorMessage, "Destination is not a memory address.");
          OutRecord->Fatal = 1;
          return (0);
        }

      OutRecord->Words[0] = Address.SReg;

      if (!strcmp(InRecord->Operator, "ADRES") || 
          !strcmp(InRecord->Operator, "DNPTR") ||
          !strcmp(InRecord->Operator, "-DNPTR"))
        {
          if (InRecord->ProgramCounter.Erasable && Address.Erasable &&
              InRecord->ProgramCounter.Banked && Address.Banked &&
              InRecord->ProgramCounter.EB != Address.EB)
            {
              strcpy(OutRecord->ErrorMessage, "Destination must be in current erasable bank.");
              OutRecord->Fatal = 1;
            }
          else if (InRecord->ProgramCounter.Fixed && Address.Fixed &&
                   InRecord->ProgramCounter.Banked && Address.Banked &&
                   (InRecord->ProgramCounter.FB != Address.FB ||
                    InRecord->ProgramCounter.Super != Address.Super))
            {
              strcpy(OutRecord->ErrorMessage, "Destination must be in current fixed bank.");
              OutRecord->Fatal = 1;
            }
        }
      else if (!strcmp(InRecord->Operator, "REMADR"))
        {
          if (InRecord->ProgramCounter.Erasable && Address.Erasable &&
              InRecord->ProgramCounter.EB == Address.EB)
            {
              strcpy(OutRecord->ErrorMessage, "Destination must not be in current erasable bank.");
              OutRecord->Fatal = 1;
            }
          else if (InRecord->ProgramCounter.Fixed && Address.Fixed &&
                   InRecord->ProgramCounter.FB == Address.FB &&
                   InRecord->ProgramCounter.Super == Address.Super)
            {
              strcpy(OutRecord->ErrorMessage, "Destination must not be in current fixed bank.");
              OutRecord->Fatal = 1;
            }
        }
    }
  else
    {
      // The operand is NOT a number.  Presumably, it's a symbol.
      i = FetchSymbolPlusOffset(&InRecord->ProgramCounter, InRecord->Operand, InRecord->Mod1, &Address);
      if (!i)
        goto DoIt;

      sprintf(OutRecord->ErrorMessage, "Symbol \"%s\" undefined or offset bad", InRecord->Operand);
      OutRecord->Fatal = 1;
      OutRecord->Words[0] = 0;
    }
  return (0);  
}