/* FCE Ultra - NES/Famicom Emulator
 *
 * Copyright notice for this file:
 *  Copyright (C) 2007 CaH4e3
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * City Fighter IV sith Sound VRC4 hacked
 */

#include "mapinc.h"

static int32 IRQCount;
static uint8 IRQa;
static uint8 prg_reg, prg_mode, mirr;
static uint8 chr_reg[8];
static writefunc pcmwrite;

static SFORMAT StateRegs[] =
{
	{ &IRQCount, 4, "IRQC" },
	{ &IRQa, 1, "IRQA" },
	{ &prg_reg, 1, "PREG" },
	{ &prg_mode, 1, "PMOD" },
	{ &mirr, 1, "MIRR" },
	{ chr_reg, 8, "CREG" },
	{ 0 }
};

static void Sync(void) {
	int i;
	setprg32(0x8000, prg_reg >> 2);
	if (!prg_mode)
		setprg8(0xC000, prg_reg);
	for (i = 0; i < 8; i++)
		setchr1(i << 10, chr_reg[i]);
	switch (mirr) {
	case 0: setmirror(MI_V); break;
	case 1: setmirror(MI_H); break;
	case 2: setmirror(MI_0); break;
	case 3: setmirror(MI_1); break;
	}
}

static DECLFW(UNLCITYFIGHTWrite) {
	/* FCEU_printf("%04x %02x",A,V); */
	switch (A & 0xF00C) {
	case 0x9000: prg_reg = V & 0xC; mirr = V & 3; break;
	case 0x9004:
	case 0x9008:
	case 0x900C:
		if (A & 0x800)
			pcmwrite(0x4011, (V & 0xf) << 3);
		else
			prg_reg = V & 0xC;
		break;
	case 0xC000:
	case 0xC004:
	case 0xC008:
	case 0xC00C: prg_mode = V & 1; break;
	case 0xD000: chr_reg[0] = (chr_reg[0] & 0xF0) | (V & 0x0F); break;
	case 0xD004: chr_reg[0] = (chr_reg[0] & 0x0F) | (V << 4); break;
	case 0xD008: chr_reg[1] = (chr_reg[1] & 0xF0) | (V & 0x0F); break;
	case 0xD00C: chr_reg[1] = (chr_reg[1] & 0x0F) | (V << 4); break;
	case 0xA000: chr_reg[2] = (chr_reg[2] & 0xF0) | (V & 0x0F); break;
	case 0xA004: chr_reg[2] = (chr_reg[2] & 0x0F) | (V << 4); break;
	case 0xA008: chr_reg[3] = (chr_reg[3] & 0xF0) | (V & 0x0F); break;
	case 0xA00C: chr_reg[3] = (chr_reg[3] & 0x0F) | (V << 4); break;
	case 0xB000: chr_reg[4] = (chr_reg[4] & 0xF0) | (V & 0x0F); break;
	case 0xB004: chr_reg[4] = (chr_reg[4] & 0x0F) | (V << 4); break;
	case 0xB008: chr_reg[5] = (chr_reg[5] & 0xF0) | (V & 0x0F); break;
	case 0xB00C: chr_reg[5] = (chr_reg[5] & 0x0F) | (V << 4); break;
	case 0xE000: chr_reg[6] = (chr_reg[6] & 0xF0) | (V & 0x0F); break;
	case 0xE004: chr_reg[6] = (chr_reg[6] & 0x0F) | (V << 4); break;
	case 0xE008: chr_reg[7] = (chr_reg[7] & 0xF0) | (V & 0x0F); break;
	case 0xE00C: chr_reg[7] = (chr_reg[7] & 0x0F) | (V << 4); break;
	case 0xF000: IRQCount = ((IRQCount & 0x1E0) | ((V & 0xF) << 1)); break;
	case 0xF004: IRQCount = ((IRQCount & 0x1E) | ((V & 0xF) << 5)); break;
	case 0xF008: IRQa = V & 2; X6502_IRQEnd(FCEU_IQEXT); break;
	default:
		break;
	}
	Sync();
}

static void UNLCITYFIGHTIRQ(int a) {
	if (IRQa) {
		IRQCount -= a;
		if (IRQCount <= 0) {
			X6502_IRQBegin(FCEU_IQEXT);
		}
	}
}

static void UNLCITYFIGHTPower(void) {
	prg_reg = 0;
	Sync();
	pcmwrite = GetWriteHandler(0x4011);
	SetReadHandler(0x8000, 0xFFFF, CartBR);
	SetWriteHandler(0x8000, 0xFFFF, UNLCITYFIGHTWrite);
}

static void StateRestore(int version) {
	Sync();
}

void UNLCITYFIGHT_Init(CartInfo *info) {
	info->Power = UNLCITYFIGHTPower;
	MapIRQHook = UNLCITYFIGHTIRQ;
	GameStateRestore = StateRestore;
	AddExState(&StateRegs, ~0, 0, 0);
}
