//////////////////////////////////////////////////////////////////////////
// Mapper163  NanJing Games                                             //
//////////////////////////////////////////////////////////////////////////

/*
//-------------------------------------------------------------------------------------
static int16 step_size[49] = {
	16, 17, 19, 21, 23, 25, 28, 31, 34, 37,
	41, 45, 50, 55, 60, 66, 73, 80, 88, 97,
	107, 118, 130, 143, 157, 173, 190, 209, 230, 253,
	279, 307, 337, 371, 408, 449, 494, 544, 598, 658,
	724, 796, 876, 963, 1060, 1166, 1282, 1411, 1552
};	//49 items
static int32 step_adj[16] = { -1, -1, -1, -1, 2, 5, 7, 9, -1, -1, -1, -1, 2, 5, 7, 9 };
//decode stuff
static int32 jedi_table[16 * 49];
static int32 acc = 0;	//ADPCM accumulator, initial condition must be 0
static int32 decstep = 0;	//ADPCM decoding step, initial condition must be 0
void	Mapper163::jedi_table_init()
{
	int step, nib;
	for (step = 0; step < 49; step++) {
		for (nib = 0; nib < 16; nib++) {
			int value = (2 * (nib & 0x07) + 1) * step_size[step] / 8;
			jedi_table[step * 16 + nib] = ((nib & 0x08) != 0) ? -value : value;
		}
	}
}
BYTE	Mapper163::decode(uint8 code)
{
	acc += jedi_table[decstep + code];
	if ((acc & ~0x7ff) != 0)	// acc is > 2047
		acc |= ~0xfff;
	else acc &= 0xfff;
	decstep += step_adj[code & 7] * 16;
	if (decstep < 0) decstep = 0;
	if (decstep > 48 * 16) decstep = 48 * 16;
	return (acc >> 8) & 0xff;
}
//-------------------------------------------------------------------------------------
*/

static int32 index_adjust[8] = {-1,-1,-1,-1,2,4,6,8};
static int16 step_table[89] = {
7,8,9,10,11,12,13,14,16,17,19,21,23,25,28,31,34,37,41,45,50,55,
60,66,73,80,88,97,107,118,130,143,157,173,190,209,230,253,279,
307,337,371,408,449,494,544,598,658,724,796,876,963,1060,
1166,1282,1411,1552,1707,1878,2066,2272,2499,2749,3024,3327,
3660,4026,4428,4871,5358,5894,6484,7132,7845,8630,9493,10442,
11487,12635,13899,15289,16818,18500,20350,22385,24623,27086,29794,32767
};

BYTE Mapper163::adpcm_decoder(BYTE data)
{
	int sb,delta;
	int cur_sample=0;
	if ((data & 8) != 0) sb=1; else sb=0;
	data&=7;
	delta = (step_table[index]*data)/4+step_table[index]/8;
	if (sb==1) delta=-delta;
	cur_sample+=delta;
	if (cur_sample>32767) cur_sample = 32767;
	else if (cur_sample<-32768) cur_sample = -32768;
	else cur_sample = cur_sample;
	index+=index_adjust[data];
	if (index<0) index=0;
	if (index>88) index=88;
	return cur_sample&0xff;
}  

void	Mapper163::Reset()
{

	index=0;

	reg[1] = 0xFF;
	strobe = 1;
	security = trigger = reg[0] = 0x00;
	rom_type = 0;
	SetPROM_32K_Bank(15);

//	jedi_table_init();

	DWORD	crc = nes->rom->GetPROM_CRC();
	if( crc == 0xb6a10d5d ) {	// Hu Lu Jin Gang (NJ039) (Ch) [dump]
		SetPROM_32K_Bank(0);
	}
	if( crc == 0xf52468e7		// San Guo Wu Shuang - Meng Jiang Zhuan (NJ047) (Ch) [dump]
	 || crc == 0x696D98E3 ) {	// San Guo Zhi Lv Bu Zhuan (NJ040) (Ch) [dump]
		rom_type = 1;
	}
	if( crc == 0xEFF96E8A ) {	// Mo Shou Shi Jie E Mo Lie Ren (NJ097) (Ch) [dump]
		rom_type = 2;
	}

	www = 0;
}

BYTE	Mapper163::ReadLow( WORD addr )
{
//	DEBUGOUT( "ReadLow  - addr= %04x\n", addr );

	if((addr>=0x5000 && addr<0x6000))
	{
		switch (addr & 0x7700)
		{
			case 0x5100:
					return security;
					break;
			case 0x5500:
					if(trigger)
						return security;
					else
						return 0;
					break;
		}
		return 4;
	}
	else if( addr>=0x6000 ) {
		return	CPU_MEM_BANK[addr>>13][addr&0x1FFF];
	}
	return Mapper::ReadLow( addr );
}

void	Mapper163::WriteLow(WORD addr, BYTE data)
{
//	if(addr==0x5200) DEBUGOUT( "WriteLow - addr= %04x ; dat= %03x\n", addr, data );

	if((addr>=0x4020 && addr<0x6000))
	{
		if(addr==0x5101){
			if(strobe && !data){
				trigger ^= 1;
//				trigger ^= 0xFF;
			}
			strobe = data;
		}else if(addr==0x5100 && data==6){
			SetPROM_32K_Bank(3);
		}
		else{
			switch (addr & 0x7300)
			{
				case 0x5000:
						reg[1]=data;
						SetPROM_32K_Bank( (reg[1] & 0xF) | (reg[0] << 4) );
						if(!(reg[1]&0x80)&&(nes->ppu->GetScanlineNo()<128))
							SetCRAM_8K_Bank(0);
						if(rom_type==1) SetCRAM_8K_Bank(0);
						break;
				case 0x5100:
						reg[2]=data;
//						nes->apu->Write(0x4011,(decode(reg[0]&0xf)<<3));
						break;
				case 0x5200:
						reg[0]=data;
						SetPROM_32K_Bank( (reg[1] & 0xF) | (reg[0] << 4) );
						break;
				case 0x5300:
						security=data;
						break;
			}
		}
	}
	else if( addr>=0x6000 ) {
		CPU_MEM_BANK[addr>>13][addr&0x1FFF] = data;
		if((addr>=0x7900 && addr<=0x79FF))
		{
//			WAVRAM[addr&0xFF] = data;
//			if(addr==0x79FF){
//				memcpy( YWRAM+(www*256), WAVRAM, 256);
//				www++;
//			}
//			nes->apu->Write(0x4011,(adpcm_decoder(data)));
			nes->apu->Write(0x4011,data);
		}
	}
}

void	Mapper163::Write( WORD addr, BYTE data )
{
//	DEBUGOUT( "Write    - addr= %04x ; dat= %03x\n", addr, data );
}

void	Mapper163::HSync(int scanline)
{
	if( (reg[1]&0x80) && nes->ppu->IsDispON() ) {
		if(scanline==127){
			SetCRAM_4K_Bank(0, 1);
			SetCRAM_4K_Bank(4, 1);
		}
		if (rom_type==1){
			if(scanline<127){
				SetCRAM_4K_Bank(0, 0);
				SetCRAM_4K_Bank(4, 0);
			}
		}else{
			if(scanline==239){
				SetCRAM_4K_Bank(0, 0);
				SetCRAM_4K_Bank(4, 0);
				if(rom_type==2) SetCRAM_4K_Bank(4, 1);
			}
		}
	}
}

void	Mapper163::PPU_Latch( WORD addr )
{
	if(DirectInput.m_Sw[DIK_PAUSE]){
		nes->Dump_YWRAM();
	}
}

void	Mapper163::SaveState( LPBYTE p )
{
	p[0] = reg[0];
	p[1] = reg[1];
}

void	Mapper163::LoadState( LPBYTE p )
{

	reg[0] = p[0];
	reg[1] = p[1];
}