/* FCE Ultra - NES/Famicom Emulator
 *
 * Copyright notice for this file:
 *  Copyright (C) 2005 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
 *
 * BMC 42-in-1 "reset switch" type
 */

#include "mapinc.h"

static uint8 regs[4];

static SFORMAT StateRegs[] =
{
	{ regs, 4, "REGS" },
	{ 0 }
};

static void Sync(void) {
	int prg = regs[0] <<7 &0x80 | regs[1] <<1 &0x7E | regs[1] >>6 &0x01;
	if (regs[0] & 0x80) { /* NROM mode */
		if (regs[1] & 0x80)
			setprg32(0x8000, prg >>1);
		else {
			setprg16(0x8000, prg);
			setprg16(0xC000, prg);
		}
	} else { /* UNROM mode */
		setprg16(0x8000, prg &~7 | regs[3] &7);
		setprg16(0xC000, prg     |          7);
	}
	if (regs[0] & 0x20)
		setmirror(MI_H);
	else
		setmirror(MI_V);
	setchr8((regs[2] << 2) | ((regs[0] >> 1) & 3));
}

static DECLFW(BMC64in1nrWriteLo) {
	regs[A &(VROM_size? 3: 1)] = V;
	Sync();
}

static DECLFW(BMC64in1nrWriteHi) {
	regs[3] = V;
	Sync();
}

static void BMC64in1nrPower(void) {
	regs[0] = 0x80;
	regs[1] = 0x43;
	regs[2] = regs[3] = 0;
	Sync();
	SetWriteHandler(0x5000, 0x5FFF, BMC64in1nrWriteLo);
	SetWriteHandler(0x8000, 0xFFFF, BMC64in1nrWriteHi);
	SetReadHandler(0x8000, 0xFFFF, CartBR);
}

static void BMC64in1nrReset(void) {
	/* Reset returns to menu */
	regs[0] = 0x80;
	regs[1] = 0x43;
	regs[2] = regs[3] = 0;
	Sync();
}

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

void BMC64in1nr_Init(CartInfo *info) {
	info->Power = BMC64in1nrPower;
	info->Reset = BMC64in1nrReset;
	AddExState(&StateRegs, ~0, 0, 0);
	GameStateRestore = StateRestore;
}