// This is part of Pico Library

// (c) Copyright 2004 Dave, All rights reserved.
// (c) Copyright 2006 notaz, All rights reserved.
// Free for non-commercial use.

// For commercial use, separate licencing terms must be obtained.


#include "PicoInt.h"

// ym2612
#include "sound/ym2612.h"

// sn76496
extern int *sn76496_regs;


struct PicoArea { void *data; int len; char *name; };

// strange observation on Symbian OS 9.1, m600 organizer fw r3a06:
// taking an address of fread or fwrite causes "application could't be started" error
// on startup randomly depending on binary layout of executable file.

arearw *areaRead  = (arearw *) 0; // fread;  // read and write function pointers for
arearw *areaWrite = (arearw *) 0; // fwrite; // gzip save state ability


// Scan one variable and callback
static int ScanVar(void *data,int len,char *name,void *PmovFile,int PmovAction)
{
  int ret = 0;
  if ((PmovAction&3)==1) ret = areaWrite(data,1,len,PmovFile);
  if ((PmovAction&3)==2) ret = areaRead (data,1,len,PmovFile);
  return (ret != len);
}

#define SCAN_VAR(x,y) ScanVar(&x,sizeof(x),y,PmovFile,PmovAction);
#define SCANP(x)      ScanVar(&Pico.x,sizeof(Pico.x),#x,PmovFile,PmovAction);

// Pack the cpu into a common format:
static int PackCpu(unsigned char *cpu)
{
  unsigned int pc=0;

#ifdef EMU_A68K
  memcpy(cpu,M68000_regs.d,0x40);
  pc=M68000_regs.pc;
  *(unsigned char *)(cpu+0x44)=(unsigned char)M68000_regs.ccr;
  *(unsigned char *)(cpu+0x45)=(unsigned char)M68000_regs.srh;
  *(unsigned int  *)(cpu+0x48)=M68000_regs.isp;
#endif

#ifdef EMU_C68K
  memcpy(cpu,PicoCpu.d,0x40);
  pc=PicoCpu.pc-PicoCpu.membase;
  *(unsigned int *)(cpu+0x44)=CycloneGetSr(&PicoCpu);
  *(unsigned int *)(cpu+0x48)=PicoCpu.osp;
#endif

#ifdef EMU_M68K
  memcpy(cpu,m68ki_cpu.dar,0x40);
  pc=m68ki_cpu.pc;
  *(unsigned int  *)(cpu+0x44)=m68k_get_reg(NULL, M68K_REG_SR);
  *(unsigned int  *)(cpu+0x48)=m68ki_cpu.sp[0];
#endif

  *(unsigned int *)(cpu+0x40)=pc;
  return 0;
}

static int UnpackCpu(unsigned char *cpu)
{
  unsigned int pc=0;

  pc=*(unsigned int *)(cpu+0x40);

#ifdef EMU_A68K
  memcpy(M68000_regs.d,cpu,0x40);
  M68000_regs.pc=pc;
  M68000_regs.ccr=*(unsigned char *)(cpu+0x44);
  M68000_regs.srh=*(unsigned char *)(cpu+0x45);
  M68000_regs.isp=*(unsigned int  *)(cpu+0x48);
#endif

#ifdef EMU_C68K
  CycloneSetSr(&PicoCpu, *(unsigned int  *)(cpu+0x44));
  PicoCpu.osp=*(unsigned int  *)(cpu+0x48);
  memcpy(PicoCpu.d,cpu,0x40);
  PicoCpu.membase=0;
  PicoCpu.pc =PicoCpu.checkpc(pc); // Base pc
#endif

#ifdef EMU_M68K
  memcpy(m68ki_cpu.dar,cpu,0x40);
  m68ki_cpu.pc=pc;
  m68k_set_reg(M68K_REG_SR, *(unsigned int *)(cpu+0x44));
  m68ki_cpu.sp[0]=*(unsigned int *)(cpu+0x48);
#endif
  return 0;
}

// Scan the contents of the virtual machine's memory for saving or loading
static int PicoAreaScan(int PmovAction,unsigned int ver, void *PmovFile)
{
  void *ym2612_regs;
  unsigned char cpu[0x60];
  unsigned char cpu_z80[0x60];
  int ret;

  memset(&cpu,0,sizeof(cpu));
  memset(&cpu_z80,0,sizeof(cpu_z80));

  ym2612_regs = YM2612GetRegs();

  if (PmovAction&4)
  {
    Pico.m.scanline=0;

	// Scan all the memory areas:
    SCANP(ram) SCANP(vram) SCANP(zram) SCANP(cram) SCANP(vsram)

    // Pack, scan and unpack the cpu data:
    if((PmovAction&3)==1) PackCpu(cpu);
    //SekInit();     // notaz: do we really have to do this here?
    //PicoMemInit();
    SCAN_VAR(cpu,"cpu")
    if((PmovAction&3)==2) UnpackCpu(cpu);

    SCAN_VAR(Pico.m    ,"misc")
    SCAN_VAR(Pico.video,"video")


	if(ver == 0x0030) { // zram was being saved incorrectly in 0x0030 (byteswaped?)
	  Byteswap(Pico.zram, 0x2000);
	  return 0; // do not try to load sound stuff
    }

	//SCAN_VAR(Pico.s    ,"sound")
	// notaz: save/load z80, YM2612, sn76496 states instead of Pico.s (which is unused anyway)
	if(PicoOpt&7) {
	  if((PmovAction&3)==1) z80_pack(cpu_z80);
      ret = SCAN_VAR(cpu_z80,"cpu_z80")
	  // do not unpack if we fail to load z80 state
	  if((PmovAction&3)==2) {
        if(ret) z80_reset();
        else    z80_unpack(cpu_z80);
      }
	}
	if(PicoOpt&3)
      ScanVar(sn76496_regs,28*4,"SN76496state", PmovFile, PmovAction); // regs and other stuff
	if(PicoOpt&1) {
      ScanVar(ym2612_regs, 0x200+4, "YM2612state", PmovFile, PmovAction); // regs + addr line
	  if((PmovAction&3)==2) YM2612PicoStateLoad(); // reload YM2612 state from it's regs
	}
  }

  return 0;
}

// ---------------------------------------------------------------------------
// Helper code to save/load to a file handle

// Save or load the state from PmovFile:
int PmovState(int PmovAction, void *PmovFile)
{
  int minimum=0;
  unsigned char head[32];

  memset(head,0,sizeof(head));

  // Find out minimal compatible version:
  //PicoAreaScan(PmovAction&0xc,&minimum);
  minimum = 0x0021;

  memcpy(head,"Pico",4);
  *(unsigned int *)(head+0x8)=PicoVer;
  *(unsigned int *)(head+0xc)=minimum;

  // Scan header:
  if (PmovAction&1) areaWrite(head,1,sizeof(head),PmovFile);
  if (PmovAction&2) areaRead (head,1,sizeof(head),PmovFile);

  // Scan memory areas:
  PicoAreaScan(PmovAction, *(unsigned int *)(head+0x8), PmovFile);

  return 0;
}