/* FCE Ultra - NES/Famicom Emulator
 *
 * Copyright notice for this file:
 *  Copyright (C) 2002 Xodnizel
 *  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
 */

#include "mapinc.h"
/* #define DEBUG90 */

/* Mapper 090 is simpliest mapper hardware and have not extended nametable control and latched chr banks in 4k mode
 * Mapper 209 much compicated hardware with decribed above features disabled by default and switchable by command
 * Mapper 211 the same mapper 209 but with forced nametable control
 */

static int is209;
static int is211;

static uint8 IRQMode;		/*  from $c001 */
static uint8 IRQPre;		/*  from $c004 */
static uint8 IRQPreSize;	/*  from $c007 */
static uint8 IRQCount;		/*  from $c005 */
static uint8 IRQXOR;		/*  Loaded from $C006 */
static uint8 IRQa;			/*  $c002, $c003, and $c000 */

static uint8 mul[2];
static uint8 regie;

static uint8 tkcom[4];
static uint8 prgb[4];
static uint8 chrlow[8];
static uint8 chrhigh[8];

static uint8 chr[2];

static uint16 names[4];
static uint8 tekker;

static SFORMAT Tek_StateRegs[] = {
	{ &IRQMode, 1, "IRQM" },
	{ &IRQPre, 1, "IRQP" },
	{ &IRQPreSize, 1, "IRQR" },
	{ &IRQCount, 1, "IRQC" },
	{ &IRQXOR, 1, "IRQX" },
	{ &IRQa, 1, "IRQA" },
	{ mul, 2, "MUL" },
	{ &regie, 1, "REGI" },
	{ tkcom, 4, "TKCO" },
	{ prgb, 4, "PRGB" },
	{ chr, 2, "CLTC" },
	{ chrlow, 4, "CHRL" },
	{ chrhigh, 8, "CHRH" },
	{ &names[0], 2 | FCEUSTATE_RLSB, "NMS0" },
	{ &names[1], 2 | FCEUSTATE_RLSB, "NMS1" },
	{ &names[2], 2 | FCEUSTATE_RLSB, "NMS2" },
	{ &names[3], 2 | FCEUSTATE_RLSB, "NMS3" },
	{ &tekker, 1, "TEKR" },
	{ 0 }
};

static void mira(void) {
	if ((tkcom[0] & 0x20 && is209) || is211) {
		int x;
		if (tkcom[0] & 0x40) {		/* Name tables are ROM-only */
			for (x = 0; x < 4; x++)
				setntamem(CHRptr[0] + (((names[x]) & CHRmask1[0]) << 10), 0, x);
		} else {					/* Name tables can be RAM or ROM. */
			for (x = 0; x < 4; x++) {
				if ((tkcom[1] & 0x80) == (names[x] & 0x80))	/* RAM selected. */
					setntamem(NTARAM + ((names[x] & 0x1) << 10), 1, x);
				else
					setntamem(CHRptr[0] + (((names[x]) & CHRmask1[0]) << 10), 0, x);
			}
		}
	} else {
		switch (tkcom[1] & 3) {
		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 void tekprom(void) {
	uint32 bankmode = ((tkcom[3] & 6) << 5);
	switch (tkcom[0] & 7) {
		case 00:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (((prgb[3] << 2) + 3) & 0x3F) | bankmode);
			setprg32(0x8000, 0x0F | ((tkcom[3] & 6) << 3));
			break;
		case 01:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (((prgb[3] << 1) + 1) & 0x3F) | bankmode);
			setprg16(0x8000, (prgb[1] & 0x1F) | ((tkcom[3] & 6) << 4));
			setprg16(0xC000, 0x1F | ((tkcom[3] & 6) << 4));
			break;
		case 03: /* bit reversion */
		case 02:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (prgb[3] & 0x3F) | bankmode);
			setprg8(0x8000, (prgb[0] & 0x3F) | bankmode);
			setprg8(0xa000, (prgb[1] & 0x3F) | bankmode);
			setprg8(0xc000, (prgb[2] & 0x3F) | bankmode);
			setprg8(0xe000, 0x3F | bankmode);
			break;
		case 04:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (((prgb[3] << 2) + 3) & 0x3F) | bankmode);
			setprg32(0x8000, (prgb[3] & 0x0F) | ((tkcom[3] & 6) << 3));
			break;
		case 05:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (((prgb[3] << 1) + 1) & 0x3F) | bankmode);
			setprg16(0x8000, (prgb[1] & 0x1F) | ((tkcom[3] & 6) << 4));
			setprg16(0xC000, (prgb[3] & 0x1F) | ((tkcom[3] & 6) << 4));
			break;
		case 07: /* bit reversion */
		case 06:
			if (tkcom[0] & 0x80)
				setprg8(0x6000, (prgb[3] & 0x3F) | bankmode);
			setprg8(0x8000, (prgb[0] & 0x3F) | bankmode);
			setprg8(0xa000, (prgb[1] & 0x3F) | bankmode);
			setprg8(0xc000, (prgb[2] & 0x3F) | bankmode);
			setprg8(0xe000, (prgb[3] & 0x3F) | bankmode);
			break;
	}
}

static void tekvrom(void) {
	int x, bank = 0, mask = 0xFFFF;
	if (!(tkcom[3] & 0x20)) {
		bank = (tkcom[3] & 1) | ((tkcom[3] & 0x18) >> 2);
		switch (tkcom[0] & 0x18) {
		case 0x00: bank <<= 5; mask = 0x1F; break;
		case 0x08: bank <<= 6; mask = 0x3F; break;
		case 0x10: bank <<= 7; mask = 0x7F; break;
		case 0x18: bank <<= 8; mask = 0xFF; break;
		}
	}
	switch (tkcom[0] & 0x18) {
	case 0x00:		/* 8KB */
		setchr8(((chrlow[0] | (chrhigh[0] << 8)) & mask) | bank);
		break;
	case 0x08:		/* 4KB */
#if 0
			for(x=0;x<8;x+=4)
				setchr4(x<<10,((chrlow[x]|(chrhigh[x]<<8))&mask)|bank);
#endif
		setchr4(0x0000, ((chrlow[chr[0]] | (chrhigh[chr[0]] << 8)) & mask) | bank);
		setchr4(0x1000, ((chrlow[chr[1]] | (chrhigh[chr[1]] << 8)) & mask) | bank);
		break;
	case 0x10:		/* 2KB */
		for (x = 0; x < 8; x += 2)
			setchr2(x << 10, ((chrlow[x] | (chrhigh[x] << 8)) & mask) | bank);
		break;
	case 0x18:		/* 1KB */
		for (x = 0; x < 8; x++)
			setchr1(x << 10, ((chrlow[x] | (chrhigh[x] << 8)) & mask) | bank);
		break;
	}
}

static DECLFW(M90TekWrite) {
	switch (A & 0x5C03) {
	case 0x5800: mul[0] = V; break;
	case 0x5801: mul[1] = V; break;
	case 0x5803: regie = V; break;
	}
}

static DECLFR(M90TekRead) {
	switch (A & 0x5C03) {
	case 0x5800: return(mul[0] * mul[1]);
	case 0x5801: return((mul[0] * mul[1]) >> 8);
	case 0x5803: return(regie);
	default: return tekker;
	}
	return(0xff);
}

static DECLFW(M90PRGWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	prgb[A & 3] = V;
	tekprom();
}

static DECLFW(M90CHRlowWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	chrlow[A & 7] = V;
	tekvrom();
}

static DECLFW(M90CHRhiWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	chrhigh[A & 7] = V;
	tekvrom();
}

static DECLFW(M90NTWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	if (A & 4) {
		names[A & 3] &= 0x00FF;
		names[A & 3] |= V << 8;
	} else {
		names[A & 3] &= 0xFF00;
		names[A & 3] |= V;
	}
	mira();
}

static DECLFW(M90IRQWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	switch (A & 7) {
	case 00:
/*			FCEU_printf("%s IRQ (C000)\n",V&1?"Enable":"Disable"); */
		IRQa = V & 1;
		if (!(V & 1))
			X6502_IRQEnd(FCEU_IQEXT);
		break;
	case 02:
/*			FCEU_printf("Disable IRQ (C002) scanline=%d\n", scanline); */
		IRQa = 0; X6502_IRQEnd(FCEU_IQEXT);
		break;
	case 03:
/*			FCEU_printf("Enable IRQ (C003) scanline=%d\n", scanline); */
		IRQa = 1;
		break;
	case 01:
		IRQMode = V;
#if 0
		FCEU_printf("IRQ Count method: ");
		switch (IRQMode&3)
		{
			case 00: FCEU_printf("M2 cycles\n");break;
			case 01: FCEU_printf("PPU A12 toggles\n");break;
			case 02: FCEU_printf("PPU reads\n");break;
			case 03: FCEU_printf("Writes to CPU space\n");break;
		}
		FCEU_printf("Counter prescaler size: %s\n",(IRQMode&4)?"3 bits":"8 bits");
		FCEU_printf("Counter prescaler size adjust: %s\n",(IRQMode&8)?"Used C007":"Normal Operation");
		if((IRQMode>>6)==2) FCEU_printf("Counter Down\n");
		else if((IRQMode>>6)==1) FCEU_printf("Counter Up\n");
		else FCEU_printf("Counter Stopped\n");
#endif
		break;
	case 04:
/*			FCEU_printf("Pre Counter Loaded and Xored wiht C006: %d\n",V^IRQXOR); */
		IRQPre = V ^ IRQXOR;
		break;
	case 05:
/*			FCEU_printf("Main Counter Loaded and Xored wiht C006: %d\n",V^IRQXOR); */
		IRQCount = V ^ IRQXOR;
		break;
	case 06:
/*			FCEU_printf("Xor Value: %d\n",V); */
		IRQXOR = V;
		break;
	case 07:
#if 0
			if(!(IRQMode&8)) FCEU_printf("C001 is clear, no effect applied\n");
			else if(V==0xFF) FCEU_printf("Prescaler is changed for 12bits\n");
			else FCEU_printf("Counter Stopped\n");
#endif
		IRQPreSize = V;
		break;
	}
}

static DECLFW(M90ModeWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
	tkcom[A & 3] = V;
	tekprom();
	tekvrom();
	mira();

#ifdef DEBUG90
	switch (A & 3) {
	case 00:
		FCEU_printf("Main Control Register:\n");
		FCEU_printf("  PGR Banking mode: %d\n", V & 7);
		FCEU_printf("  CHR Banking mode: %d\n", (V >> 3) & 3);
		FCEU_printf("  6000-7FFF addresses mapping: %s\n", (V & 0x80) ? "Yes" : "No");
		FCEU_printf("  Nametable control: %s\n", (V & 0x20) ? "Enabled" : "Disabled");
		if (V & 0x20)
			FCEU_printf("  Nametable can be: %s\n", (V & 0x40) ? "ROM Only" : "RAM or ROM");
		break;
	case 01:
		FCEU_printf("Mirroring mode: ");
		switch (V & 3) {
		case 0: FCEU_printf("Vertical\n"); break;
		case 1: FCEU_printf("Horizontal\n"); break;
		case 2: FCEU_printf("Nametable 0 only\n"); break;
		case 3: FCEU_printf("Nametable 1 only\n"); break;
		}
		FCEU_printf("Mirroring flag: %s\n", (V & 0x80) ? "On" : "Off");
		break;
	case 02:
		if ((((tkcom[0]) >> 5) & 3) == 1)
			FCEU_printf("Nametable ROM/RAM select mode: %d\n", V >> 7);
		break;
	case 03:
		FCEU_printf("CHR Banking mode: %s\n", (V & 0x20) ? "Entire CHR ROM" : "256Kb Switching mode");
		if (!(V & 0x20)) FCEU_printf("256K CHR bank number: %02x\n", (V & 1) | ((V & 0x18) >> 2));
		FCEU_printf("512K PRG bank number: %d\n", (V & 6) >> 1);
		FCEU_printf("CHR Bank mirroring: %s\n", (V & 0x80) ? "Swapped" : "Normal operate");
	}
#endif
}

static DECLFW(M90DummyWrite) {
/*	FCEU_printf("bs %04x %02x\n",A,V); */
}

static void CCL(void) {
	if ((IRQMode >> 6) == 1) {	/* Count Up */
		IRQCount++;
		if ((IRQCount == 0) && IRQa) {
			X6502_IRQBegin(FCEU_IQEXT);
		}
	} else if ((IRQMode >> 6) == 2) {	/* Count down */
		IRQCount--;
		if ((IRQCount == 0xFF) && IRQa) {
			X6502_IRQBegin(FCEU_IQEXT);
		}
	}
}

static void ClockCounter(void) {
	uint8 premask;

	if (IRQMode & 0x4)
		premask = 0x7;
	else
		premask = 0xFF;
	if ((IRQMode >> 6) == 1) {	/* Count up */
		IRQPre++;
		if ((IRQPre & premask) == 0) CCL();
	} else if ((IRQMode >> 6) == 2) {	/* Count down */
		IRQPre--;
		if ((IRQPre & premask) == premask) CCL();
	}
}

void FP_FASTAPASS(1) CPUWrap(int a) {
	int x;
	if ((IRQMode & 3) == 0) for (x = 0; x < a; x++) ClockCounter();
}

static void SLWrap(void) {
	int x;
	if ((IRQMode & 3) == 1) for (x = 0; x < 8; x++) ClockCounter();
}

static uint32 lastread;
static void FP_FASTAPASS(1) M90PPU(uint32 A) {
	if ((IRQMode & 3) == 2) {
		if (lastread != A) {
			ClockCounter();
			ClockCounter();
		}
		lastread = A;
	}

	if (is209) {
		uint8 l, h;
		h = A >> 8;
		if (h < 0x20 && ((h & 0x0F) == 0xF)) {
			l = A & 0xF0;
			if (l == 0xD0) {
				chr[(h & 0x10) >> 4] = ((h & 0x10) >> 2);
				tekvrom();
			} else if (l == 0xE0) {
				chr[(h & 0x10) >> 4] = ((h & 0x10) >> 2) | 2;
				tekvrom();
			}
		}
	} else {
		chr[0] = 0;
		chr[1] = 4;
	}
}

static void togglie(void) {
	tekker += 0x40;
	tekker &= 0xC0;
	FCEU_printf("tekker=%02x\n", tekker);
	memset(tkcom, 0x00, sizeof(tkcom));
	memset(prgb, 0xff, sizeof(prgb));
	tekprom();
	tekvrom();
}

static void M90Restore(int version) {
	tekprom();
	tekvrom();
	mira();
}

static void M90Power(void) {
	SetWriteHandler(0x5000, 0x5fff, M90TekWrite);
	SetWriteHandler(0x8000, 0x8ff0, M90PRGWrite);
	SetWriteHandler(0x9000, 0x9fff, M90CHRlowWrite);
	SetWriteHandler(0xA000, 0xAfff, M90CHRhiWrite);
	SetWriteHandler(0xB000, 0xBfff, M90NTWrite);
	SetWriteHandler(0xC000, 0xCfff, M90IRQWrite);
	SetWriteHandler(0xD000, 0xD5ff, M90ModeWrite);
	SetWriteHandler(0xE000, 0xFfff, M90DummyWrite);

	SetReadHandler(0x5000, 0x5fff, M90TekRead);
	SetReadHandler(0x6000, 0xffff, CartBR);

	mul[0] = mul[1] = regie = 0xFF;

	memset(tkcom, 0x00, sizeof(tkcom));
	memset(prgb, 0xff, sizeof(prgb));
	memset(chrlow, 0xff, sizeof(chrlow));
	memset(chrhigh, 0xff, sizeof(chrhigh));
	memset(names, 0x00, sizeof(names));

	if (is211)
		tekker = 0xC0;
	else
		tekker = 0x00;

	tekprom();
	tekvrom();
}

void Mapper90_Init(CartInfo *info) {
	is211 = 0;
	is209 = 0;
	info->Reset = togglie;
	info->Power = M90Power;
	PPU_hook = M90PPU;
	MapIRQHook = CPUWrap;
	GameHBIRQHook2 = SLWrap;
	GameStateRestore = M90Restore;
	AddExState(Tek_StateRegs, ~0, 0, 0);
}

void Mapper209_Init(CartInfo *info) {
	is211 = 0;
	is209 = 1;
	info->Reset = togglie;
	info->Power = M90Power;
	PPU_hook = M90PPU;
	MapIRQHook = CPUWrap;
	GameHBIRQHook2 = SLWrap;
	GameStateRestore = M90Restore;
	AddExState(Tek_StateRegs, ~0, 0, 0);
}

void Mapper211_Init(CartInfo *info) {
	is211 = 1;
	info->Reset = togglie;
	info->Power = M90Power;
	PPU_hook = M90PPU;
	MapIRQHook = CPUWrap;
	GameHBIRQHook2 = SLWrap;
	GameStateRestore = M90Restore;
	AddExState(Tek_StateRegs, ~0, 0, 0);
}