//
// Copyright (c) 2004 K. Wilkins
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from
// the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would be
//    appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
//    be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//

//////////////////////////////////////////////////////////////////////////////
//                       Handy - An Atari Lynx Emulator                     //
//                          Copyright (c) 1996,1997                         //
//                                 K. Wilkins                               //
//////////////////////////////////////////////////////////////////////////////
// ROM emulation class                                                      //
//////////////////////////////////////////////////////////////////////////////
//                                                                          //
// This class emulates the system ROM (512B), the interface is pretty       //
// simple: constructor, reset, peek, poke.                                  //
//                                                                          //
//    K. Wilkins                                                            //
// August 1997                                                              //
//                                                                          //
//////////////////////////////////////////////////////////////////////////////
// Revision History:                                                        //
// -----------------                                                        //
//                                                                          //
// 01Aug1997 KW Document header added & class documented.                   //
//                                                                          //
//////////////////////////////////////////////////////////////////////////////

#define ROM_CPP

//#include <crtdbg.h>
//#define   TRACE_ROM

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "system.h"
#include "rom.h"

extern CErrorInterface *gError;

CRom::CRom(const char *romfile,bool useEmu)
{
   mWriteEnable = FALSE;
   mValid = TRUE;
   strncpy(mFileName,romfile,1024);
   Reset();

   // Initialise ROM
   for(int loop=0;loop<ROM_SIZE;loop++) mRomData[loop]=DEFAULT_ROM_CONTENTS;
   // actually not part of Boot ROM but uninitialized otherwise
   // Reset Vector etc
   mRomData[0x1F8]=0x00;
   mRomData[0x1F9]=0x80;
   mRomData[0x1FA]=0x00;
   mRomData[0x1FB]=0x30;
   mRomData[0x1FC]=0x80;
   mRomData[0x1FD]=0xFF;
   mRomData[0x1FE]=0x80;
   mRomData[0x1FF]=0xFF;

   if(useEmu){
      mValid = FALSE;
   }else{
      // Load up the file

      FILE	*fp;

      if((fp=fopen(mFileName,"rb"))==NULL)
      {
        fprintf(stdout, "The Lynx Boot ROM image couldn't be located! Using built-in replacement\n");
        mValid = FALSE;
      }else{
         // Read in the 512 bytes
         fprintf(stdout, "Read Lynx Boot ROM image\n");

         if(fread(mRomData,sizeof(char),ROM_SIZE,fp)!=ROM_SIZE)
         {
            fprintf(stdout, "The Lynx Boot ROM image couldn't be loaded! Using built-in replacement\n");
            mValid = FALSE;
         }
         if(fp) fclose(fp);
      }

      // Check the code that has been loaded and report an error if its a
      // fake version (from handy distribution) of the bootrom
      // would be more intelligent to make a crc

      if(mRomData[0x1FE]!=0x80 || mRomData[0x1FF]!=0xFF){
         fprintf(stdout, "The Lynx Boot ROM image is invalid! Using built-in replacement\n");
         mValid = FALSE;
      }

      if(mValid==FALSE){
         fprintf(stdout, "The chosen bootrom is not existing or invalid.\n"
                      "Switching now to bootrom emulation.\n"
                     );
      }
   }
}

void CRom::Reset(void)
{
   // Nothing to do here
}

bool CRom::ContextSave(FILE *fp)
{
   if(!fprintf(fp,"CRom::ContextSave")) return 0;
   if(!fwrite(mRomData,sizeof(UBYTE),ROM_SIZE,fp)) return 0;
   return 1;
}

bool CRom::ContextLoad(LSS_FILE *fp)
{
   char teststr[100]="XXXXXXXXXXXXXXXXX";
   if(!lss_read(teststr,sizeof(char),17,fp)) return 0;
   if(strcmp(teststr,"CRom::ContextSave")!=0) return 0;

   if(!lss_read(mRomData,sizeof(UBYTE),ROM_SIZE,fp)) return 0;
   return 1;
}


//END OF FILE
