#include <stdio.h>
#include <string.h>
#include "cpu_68k.h"
#include "gens_core/mem/mem_m68k.h"
#include "gens_core/mem/mem_s68k.h"
#include "gens_core/mem/mem_sh2.h"
#include "util/file/save.hpp"
#include "gens_core/sound/ym2612.h"
#include "gens_core/misc/misc.h"
#include "gens_core/gfx/gfx_cd.h"

#include "gens_core/io/io.h"
#include "segacd/cd_sys.hpp"


#define GENESIS 0
#define _32X    1
#define SEGACD  2

/*** global variables ***/

struct S68000CONTEXT Context_68K;

struct STARSCREAM_PROGRAMREGION M68K_Fetch[] = {
  {0x000000, 0x3FFFFF, (unsigned) 0x000000},
  {0xFF0000, 0xFFFFFF, (unsigned) &Ram_68k[0] - 0xFF0000},
  {0xF00000, 0xF0FFFF, (unsigned) &Ram_68k[0] - 0xF00000},
  {0xEF0000, 0xEFFFFF, (unsigned) &Ram_68k[0] - 0xEF0000},
  {-1, -1, (unsigned) NULL},
  {-1, -1, (unsigned) NULL},
  {-1, -1, (unsigned) NULL}
};

struct STARSCREAM_DATAREGION M68K_Read_Byte[5] = {
  {0x000000, 0x3FFFFF, NULL, NULL},
  {0xFF0000, 0xFFFFFF, NULL, &Ram_68k[0]},
  {0x400000, 0xFEFFFF, (void *) M68K_RB, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION M68K_Read_Word[5] = {
  {0x000000, 0x3FFFFF, NULL, NULL},
  {0xFF0000, 0xFFFFFF, NULL, &Ram_68k[0]},
  {0x400000, 0xFEFFFF, (void *) M68K_RW, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION M68K_Write_Byte[] = {
  {0xFF0000, 0xFFFFFF, NULL, &Ram_68k[0]},
  {0x000000, 0xFEFFFF, (void *) M68K_WB, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION M68K_Write_Word[] = {
  {0xFF0000, 0xFFFFFF, NULL, &Ram_68k[0]},
  {0x000000, 0xFEFFFF, (void *) M68K_WW, NULL},
  {-1, -1, NULL, NULL}
};


struct STARSCREAM_PROGRAMREGION S68K_Fetch[] = {
  {0x000000, 0x07FFFF, (unsigned) &Ram_Prg[0]},
  {-1, -1, (unsigned) NULL},
  {-1, -1, (unsigned) NULL}
};

struct STARSCREAM_DATAREGION S68K_Read_Byte[] = {
  {0x000000, 0x07FFFF, NULL, &Ram_Prg[0]},
  {0x080000, 0xFFFFFF, (void *) S68K_RB, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION S68K_Read_Word[] = {
  {0x000000, 0x07FFFF, NULL, &Ram_Prg[0]},
  {0x080000, 0xFFFFFF, (void *) S68K_RW, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION S68K_Write_Byte[] = {
  {0x000000, 0x07FFFF, NULL, &Ram_Prg[0]},
  {0x080000, 0xFFFFFF, (void *) S68K_WB, NULL},
  {-1, -1, NULL, NULL}
};

struct STARSCREAM_DATAREGION S68K_Write_Word[] = {
  {0x000000, 0x07FFFF, NULL, &Ram_Prg[0]},
  {0x080000, 0xFFFFFF, (void *) S68K_WW, NULL},
  {-1, -1, NULL, NULL}
};


void
M68K_Reset_Handler ()
{
//      Init_Memory_M68K(GENESIS);
}


void
S68K_Reset_Handler ()
{
//      Init_Memory_M68K(SEGACD);
}


/*** M68K_Init - initialise the main 68K ***/

int
M68K_Init (void)
{
  memset (&Context_68K, 0, sizeof (Context_68K));

  Context_68K.s_fetch = Context_68K.u_fetch = Context_68K.fetch = M68K_Fetch;
  Context_68K.s_readbyte = Context_68K.u_readbyte = Context_68K.readbyte =
    M68K_Read_Byte;
  Context_68K.s_readword = Context_68K.u_readword = Context_68K.readword =
    M68K_Read_Word;
  Context_68K.s_writebyte = Context_68K.u_writebyte = Context_68K.writebyte =
    M68K_Write_Byte;
  Context_68K.s_writeword = Context_68K.u_writeword = Context_68K.writeword =
    M68K_Write_Word;
  Context_68K.resethandler = (void *) M68K_Reset_Handler;

  main68k_SetContext (&Context_68K);
  main68k_init ();

  return 1;
}


/*** S68K_Init - initialise the sub 68K ***/

int
S68K_Init (void)
{
  memset (&Context_68K, 0, sizeof (Context_68K));

  Context_68K.s_fetch = Context_68K.u_fetch = Context_68K.fetch = S68K_Fetch;
  Context_68K.s_readbyte = Context_68K.u_readbyte = Context_68K.readbyte =
    S68K_Read_Byte;
  Context_68K.s_readword = Context_68K.u_readword = Context_68K.readword =
    S68K_Read_Word;
  Context_68K.s_writebyte = Context_68K.u_writebyte = Context_68K.writebyte =
    S68K_Write_Byte;
  Context_68K.s_writeword = Context_68K.u_writeword = Context_68K.writeword =
    S68K_Write_Word;
  Context_68K.resethandler = (void *) S68K_Reset_Handler;

  sub68k_SetContext (&Context_68K);
  sub68k_init ();

  return 1;
}


/*** M68K_Reset - general reset of the main 68K CPU ***/

void
M68K_Reset (int System_ID)
{
  memset (Ram_68k, 0, 64 * 1024);

  M68K_Fetch[0].lowaddr = 0x000000;
  M68K_Fetch[0].highaddr = Rom_Size - 1;
  M68K_Fetch[0].offset = (unsigned) &Rom_Data[0] - 0x000000;

  M68K_Fetch[1].lowaddr = 0xFF0000;
  M68K_Fetch[1].highaddr = 0xFFFFFF;
  M68K_Fetch[1].offset = (unsigned) &Ram_68k[0] - 0xFF0000;

  if (System_ID == GENESIS)
    {
      M68K_Fetch[2].lowaddr = 0xF00000;
      M68K_Fetch[2].highaddr = 0xF0FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_68k[0] - 0xF00000;

      M68K_Fetch[3].lowaddr = 0xEF0000;
      M68K_Fetch[3].highaddr = 0xEFFFFF;
      M68K_Fetch[3].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

      M68K_Fetch[4].lowaddr = -1;
      M68K_Fetch[4].highaddr = -1;
      M68K_Fetch[4].offset = (unsigned) NULL;


    }
  else if (System_ID == _32X)
    {
      Bank_SH2 = 0;

      M68K_Fetch[2].lowaddr = 0xF00000;
      M68K_Fetch[2].highaddr = 0xF0FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_68k[0] - 0xF00000;

      M68K_Fetch[3].lowaddr = 0xEF0000;
      M68K_Fetch[3].highaddr = 0xEFFFFF;
      M68K_Fetch[3].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

      M68K_Fetch[4].lowaddr = -1;
      M68K_Fetch[4].highaddr = -1;
      M68K_Fetch[4].offset = (unsigned) NULL;
    }
  else if (System_ID == SEGACD)
    {
      Bank_M68K = 0;

      MS68K_Set_Word_Ram ();

      M68K_Fetch[3].lowaddr = 0x020000;
      M68K_Fetch[3].highaddr = 0x03FFFF;
      M68K_Set_Prg_Ram ();

      M68K_Fetch[4].lowaddr = 0xF00000;
      M68K_Fetch[4].highaddr = 0xF0FFFF;
      M68K_Fetch[4].offset = (unsigned) &Ram_68k[0] - 0xF00000;

      M68K_Fetch[5].lowaddr = 0xEF0000;
      M68K_Fetch[5].highaddr = 0xEFFFFF;
      M68K_Fetch[5].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

      M68K_Fetch[6].lowaddr = -1;
      M68K_Fetch[6].highaddr = -1;
      M68K_Fetch[6].offset = (unsigned) NULL;
    }

  main68k_reset ();

  Init_Memory_M68K (System_ID);
}


/*** S68K_Reset - general reset of the sub 68K CPU ***/

void
S68K_Reset (void)
{
  memset (Ram_Prg, 0, 512 * 1024);
  memset (Ram_Word_2M, 0, 256 * 1024);
  memset (Ram_Word_1M, 0, 256 * 1024);

  memset (COMM.Command, 0, 8 * 5);
  memset (COMM.Status, 0, 8 * 5);

  LED_Status = S68K_State = S68K_Mem_WP = S68K_Mem_PM = Ram_Word_State = 0;
  COMM.Flag = Init_Timer_INT3 = Timer_INT3 = Int_Mask_S68K = 0;
  Font_COLOR = Font_BITS = 0;

  MS68K_Set_Word_Ram ();

  sub68k_reset ();
}




/***   M68K_32X_Mode - modify 32x mode    ***
 *** - Called only during 32X emulation - ***/

void
M68K_32X_Mode ()
{
//      if (_32X_ADEN && !_32X_RV)                      // 32X ON
  if (_32X_ADEN)		// 32X ON
    {
      if (!_32X_RV)		// ROM MOVED
	{
	  M68K_Fetch[0].lowaddr = 0x880000;
	  M68K_Fetch[0].highaddr = 0x8FFFFF;
	  M68K_Fetch[0].offset = (unsigned) &Rom_Data[0] - 0x880000;

	  M68K_Fetch[1].lowaddr = 0x900000;
	  M68K_Fetch[1].highaddr = 0x9FFFFF;
	  M68K_Set_32X_Rom_Bank ();

	  M68K_Fetch[2].lowaddr = 0xFF0000;
	  M68K_Fetch[2].highaddr = 0xFFFFFF;
	  M68K_Fetch[2].offset = (unsigned) &Ram_68k[0] - 0xFF0000;

	  M68K_Fetch[3].lowaddr = 0x00;
	  M68K_Fetch[3].highaddr = 0xFF;
	  M68K_Fetch[3].offset = (unsigned) &_32X_Genesis_Rom[0] - 0x000000;

	  M68K_Fetch[4].lowaddr = 0xEF0000;
	  M68K_Fetch[4].highaddr = 0xEFFFFF;
	  M68K_Fetch[4].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

	  M68K_Fetch[5].lowaddr = 0xF00000;
	  M68K_Fetch[5].highaddr = 0xF0FFFF;
	  M68K_Fetch[5].offset = (unsigned) &Ram_68k[0] - 0xF00000;

	  M68K_Fetch[6].lowaddr = -1;
	  M68K_Fetch[6].highaddr = -1;
	  M68K_Fetch[6].offset = (unsigned) NULL;

	  M68K_Read_Byte_Table[0] = _32X_M68K_Read_Byte_Table[4 * 2];
	  M68K_Read_Word_Table[0] = _32X_M68K_Read_Word_Table[4 * 2];
	}
      else			// ROM NOT MOVED BUT BIOS PRESENT
	{
	  M68K_Fetch[0].lowaddr = 0x000100;
	  M68K_Fetch[0].highaddr = Rom_Size - 1;
	  M68K_Fetch[0].offset = (unsigned) &Rom_Data[0] - 0x000000;

	  M68K_Fetch[1].lowaddr = 0xFF0000;
	  M68K_Fetch[1].highaddr = 0xFFFFFF;
	  M68K_Fetch[1].offset = (unsigned) &Ram_68k[0] - 0xFF0000;

	  M68K_Fetch[2].lowaddr = 0x00;
	  M68K_Fetch[2].highaddr = 0xFF;
	  M68K_Fetch[2].offset = (unsigned) &_32X_Genesis_Rom[0] - 0x000000;

	  M68K_Fetch[3].lowaddr = 0xF00000;
	  M68K_Fetch[3].highaddr = 0xF0FFFF;
	  M68K_Fetch[3].offset = (unsigned) &Ram_68k[0] - 0xF00000;

	  M68K_Fetch[4].lowaddr = 0xEF0000;
	  M68K_Fetch[4].highaddr = 0xEFFFFF;
	  M68K_Fetch[4].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

	  M68K_Fetch[5].lowaddr = -1;
	  M68K_Fetch[5].highaddr = -1;
	  M68K_Fetch[5].offset = (unsigned) NULL;

	  M68K_Read_Byte_Table[0] = _32X_M68K_Read_Byte_Table[4 * 2 + 1];
	  M68K_Read_Word_Table[0] = _32X_M68K_Read_Word_Table[4 * 2 + 1];
	}
    }
  else
    {
      M68K_Fetch[0].lowaddr = 0x000000;
      M68K_Fetch[0].highaddr = Rom_Size - 1;
      M68K_Fetch[0].offset = (unsigned) &Rom_Data[0] - 0x000000;

      M68K_Fetch[1].lowaddr = 0xFF0000;
      M68K_Fetch[1].highaddr = 0xFFFFFF;
      M68K_Fetch[1].offset = (unsigned) &Ram_68k[0] - 0xFF0000;

      M68K_Fetch[2].lowaddr = 0xF00000;
      M68K_Fetch[2].highaddr = 0xF0FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_68k[0] - 0xF00000;

      M68K_Fetch[3].lowaddr = 0xEF0000;
      M68K_Fetch[3].highaddr = 0xEFFFFF;
      M68K_Fetch[3].offset = (unsigned) &Ram_68k[0] - 0xEF0000;

      M68K_Fetch[4].lowaddr = -1;
      M68K_Fetch[4].highaddr = -1;
      M68K_Fetch[4].offset = (unsigned) NULL;

      M68K_Read_Byte_Table[0] = _32X_M68K_Read_Byte_Table[0];
      M68K_Read_Word_Table[0] = _32X_M68K_Read_Word_Table[0];
    }
}


/*** M68K_Set_32X_Rom_Bank - modify 32x rom bank ***
 ***     - Called only during 32X emulation -    ***/

void
M68K_Set_32X_Rom_Bank ()
{
  if (_32X_ADEN && !_32X_RV)
    {
      M68K_Fetch[1].offset = (unsigned) &Rom_Data[Bank_SH2 << 20] - 0x900000;

      M68K_Read_Byte_Table[(9 * 2) + 0] =
	_32X_M68K_Read_Byte_Table[(Bank_SH2 << 1) + 0];
      M68K_Read_Byte_Table[(9 * 2) + 1] =
	_32X_M68K_Read_Byte_Table[(Bank_SH2 << 1) + 1];
      M68K_Read_Word_Table[(9 * 2) + 0] =
	_32X_M68K_Read_Word_Table[(Bank_SH2 << 1) + 0];
      M68K_Read_Word_Table[(9 * 2) + 1] =
	_32X_M68K_Read_Word_Table[(Bank_SH2 << 1) + 1];
    }
  else
    {


    }
}


/*** M68K_Set_Prg_Ram - modify bank Prg_Ram fetch ***
 ***   - Called only during SEGA CD emulation -   ***/

void
M68K_Set_Prg_Ram ()
{
  M68K_Fetch[3].offset = (unsigned) &Ram_Prg[Bank_M68K] - 0x020000;
}


/*** MS68K_Set_Word_Ram - modify bank Word_Ram fetch ***
 ***    - Called only during SEGA CD emulation -     ***/

void
MS68K_Set_Word_Ram (void)
{
  switch (Ram_Word_State)
    {
    case 0:			// Mode 2M -> Assigned to Main CPU
      M68K_Fetch[2].lowaddr = 0x200000;
      M68K_Fetch[2].highaddr = 0x23FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_Word_2M[0] - 0x200000;

//                      S68K_Fetch[1].lowaddr = -1;
//                      S68K_Fetch[1].highaddr = -1;            
//                      S68K_Fetch[1].offset = (unsigned) NULL;

      S68K_Fetch[1].lowaddr = 0x080000;	// why not after all...
      S68K_Fetch[1].highaddr = 0x0BFFFF;
      S68K_Fetch[1].offset = (unsigned) &Ram_Word_2M[0] - 0x080000;
      break;

    case 1:			// Mode 2M -> Assigned to Sub CPU
//                      M68K_Fetch[2].lowaddr = -1;
//                      M68K_Fetch[2].highaddr = -1;
//                      M68K_Fetch[2].offset = (unsigned) NULL;

      M68K_Fetch[2].lowaddr = 0x200000;	// why not after all...
      M68K_Fetch[2].highaddr = 0x23FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_Word_2M[0] - 0x200000;

      S68K_Fetch[1].lowaddr = 0x080000;
      S68K_Fetch[1].highaddr = 0x0BFFFF;
      S68K_Fetch[1].offset = (unsigned) &Ram_Word_2M[0] - 0x080000;
      break;

    case 2:			// Mode 1M -> Bank 0 to Main CPU
      M68K_Fetch[2].lowaddr = 0x200000;	// Bank 0
      M68K_Fetch[2].highaddr = 0x21FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_Word_1M[0] - 0x200000;

      S68K_Fetch[1].lowaddr = 0x0C0000;	// Bank 1
      S68K_Fetch[1].highaddr = 0x0DFFFF;
      S68K_Fetch[1].offset = (unsigned) &Ram_Word_1M[0x20000] - 0x0C0000;
      break;

    case 3:			// Mode 1M -> Bank 0 to Sub CPU
      M68K_Fetch[2].lowaddr = 0x200000;	// Bank 1
      M68K_Fetch[2].highaddr = 0x21FFFF;
      M68K_Fetch[2].offset = (unsigned) &Ram_Word_1M[0x20000] - 0x200000;

      S68K_Fetch[1].lowaddr = 0x0C0000;	// Bank 0
      S68K_Fetch[1].highaddr = 0x0DFFFF;
      S68K_Fetch[1].offset = (unsigned) &Ram_Word_1M[0] - 0x0C0000;
      break;
    }
}


/*** M68K_Reset_CPU - just reset the main 68K cpu ***/

void
M68K_Reset_CPU ()
{
  main68k_reset ();
}


/*** S68K_Reset_CPU - just reset the sub 68K cpu ***/

void
S68K_Reset_CPU ()
{
  sub68k_reset ();
}

void _M68K_Set_32X_Rom_Bank ()
  __attribute__ ((weak, alias ("M68K_Set_32X_Rom_Bank")));
void _M68K_Set_Prg_Ram () __attribute__ ((weak, alias ("M68K_Set_Prg_Ram")));
void _M68K_32X_Mode () __attribute__ ((weak, alias ("M68K_32X_Mode")));
void _MS68K_Set_Word_Ram (void)
  __attribute__ ((weak, alias ("MS68K_Set_Word_Ram")));
