gb.hexpat

#pragma author WerWolv
#pragma description Gameboy ROM

#pragma MIME application/x-gameboy-rom

import type.size;
import std.string;
import std.mem;

const u16 ROMBANKSIZE_16K = 0x4000;
const u16 ROMBANKSIZE_32K = 0x8000;

bool uppercaseROMFeatures in;
bool brandedROMFeatures in;

bitfield CGB {
	padding : 2;
	PGB_MODE : 2;
	padding : 2;
	CGB_ONLY : 1 [[comment("gbcOnly")]];
	CGB_SUPPORT : 1 [[comment("supportsGBC")]];
} [[comment("GBCFlags")]];

namespace format {
	fn cart_size(u8 cartSizeType) {
		u32 romSize = 32768 * (1 << cartSizeType);
		u16 romBanks = 2 * (1 << cartSizeType);
		if (cartSizeType == 0x52) {
			romSize = 1153434;
			romBanks = 72;
		}
		if (cartSizeType == 0x53) {
			romSize = 1258291;
			romBanks = 80;
		}
		if (cartSizeType == 0x54) {
			romSize = 1572864;
			romBanks = 96;
		}
		return std::format("size: {}, banks: {}", type::impl::size_formatter(romSize), romBanks);
	};

	fn ram_type(u8 ramType) {
		u16 ramSize;
		u16 ramBanks;
		if(ramType == 2) {
			ramSize = 8192;
			ramBanks = 1;
		}
		if(ramType == 3) {
			ramSize = 32768;
			ramBanks = 4;
		}
		if(ramType == 4) {
			ramSize = 131072;
			ramBanks = 16;
		}
		if(ramType == 5) {
			ramSize = 65536;
			ramBanks = 8;
		}
		return std::format("size: {}, banks: {}", type::impl::size_formatter(ramSize), ramBanks);
	};

	fn rom_features(u8 type) {
		str result = "( ";
		if (brandedROMFeatures) match(type) {
				(0xFC): result += "pocket ";
				(0xFD): result += "bandai ";
			}
		match(type) {
			(0x00): result += "no_mbc";
			(0x01): result += "mbc1";
			(0x02): result += "mbc1 | ram";
			(0x03): result += "mbc1 | ram | battery";
			(0x05): result += "mbc2";
			(0x06): result += "mbc2 | battery";
			(0x08): result += "no_mbc | ram";
			(0x09): result += "no_mbc | ram | battery";
			(0x0B): result += "mmm01";
			(0x0C): result += "mmm01 | ram";
			(0x0D): result += "mmm01 | ram | battery";
			(0x0F): result += "mbc3 | timer | battery";
			(0x10): result += "mbc3 | timer | ram | battery";
			(0x11): result += "mbc3";
			(0x12): result += "mbc3 | ram";
			(0x13): result += "mbc3 | ram | battery";
			(0x19): result += "mbc5";
			(0x1A): result += "mbc5 | ram";
			(0x1B): result += "mbc5 | ram | battery";
			(0x1C): result += "mbc5 | rumble";
			(0x1D): result += "mbc5 | rumble | ram";
			(0x1E): result += "mbc5 | rumble | ram | battery";
			(0x20): result += "mbc6";
			(0x22): result += "mbc7 | sensor | rumble";
			(0xFC): result += "camera";
			(0xFD): result += "tama5";
			(0xFE): result += "huc3";
			(0xFF): result += "huc1 | ram | battery";
		}
		if (uppercaseROMFeatures) result = std::string::to_upper(result);
		return result + " )";
	};

	fn licensee_code(u8 code) {
		match(code) {
			(0x00): return "None";
			(0x01 | 0x31): return "Nintendo";
			(0x08 | 0x38): return "Capcom";
			(0x09): return "Hot-B";
			(0x0A | 0xE0): return "Jaleco";
			(0x0B): return "Coconuts Japan";
			(0x0C | 0x6E): return "Elite Systems";
			(0x13 | 0x69): return "EA (Electronic Arts)";
			(0x18): return "Hudsonsoft";
			(0x19): return "ITC Entertainment";
			(0x1A): return "Yanoman";
			(0x1D): return "Japan Clary";
			(0x1F | 0x4A | 0x61): return "Virgin Interactive";
			(0x24): return "PCM Complete";
			(0x25): return "San-X";
			(0x28): return "Kotobuki Systems";
			(0x29): return "Seta";
			(0x30 | 0x70): return "Infogrames";
			(0x32 | 0xA2 | 0xB2 | 0xC4): return "Bandai";
			(0x33): return "See new licensee code";
			(0x34 | 0xA4): return "Konami";
			(0x35): return "HectorSoft";
			(0x39 | 0x9D): return "Banpresto";
			(0x3C): return ".Entertainment i";
			(0x3E): return "Gremlin";
			(0x41): return "Ubisoft";
			(0x42 | 0xEB): return "Atlus";
			(0x44 | 0x4D): return "Malibu";
			(0x46 | 0xCF): return "Angel";
			(0x47): return "Spectrum Holoby";
			(0x49): return "Irem";
			(0x4F): return "U.S. Gold";
			(0x50): return "Absolute";
			(0x51 | 0xB0): return "Acclaim";
			(0x52): return "Activision";
			(0x53): return "American Sammy";
			(0x54): return "GameTek";
			(0x55): return "Park Place";
			(0x56 | 0xDB | 0xFF): return "LJN";
			(0x57): return "Matchbox";
			(0x59): return "Milton Bradley";
			(0x5A): return "Mindscape";
			(0x5B): return "Romstar";
			(0x5C | 0xD6): return "Naxat Soft";
			(0x5D): return "Tradewest";
			(0x60): return "Titus";
			(0x67): return "Ocean Interactive";
			(0x6F): return "Electro Brain";
			(0x71): return "Interplay";
			(0x72 | 0xAA): return "Broderbund";
			(0x73): return "Sculptered Soft";
			(0x75): return "The Sales Curve";
			(0x78): return "t.hq";
			(0x79): return "Accolade";
			(0x7A): return "Triffix Entertainment";
			(0x7C): return "Microprose";
			(0x7F | 0xC2): return "Kemco";
			(0x80): return "Misawa Entertainment";
			(0x83): return "Lozc";
			(0x86 | 0xC4): return "Tokuma Shoten Intermedia";
			(0x8B): return "Bullet-Proof Software";
			(0x8C): return "Vic Tokai";
			(0x8E): return "Ape";
			(0x8F): return "I'Max";
			(0x91): return "Chunksoft Co.";
			(0x92): return "Video System";
			(0x93): return "Tsubaraya Productions Co.";
			(0x95): return "Varie Corporation";
			(0x96): return "Yonezawa/S’Pal";
			(0x97): return "Kaneko";
			(0x99): return "Arc";
			(0x9A): return "Nihon Bussan";
			(0x9B): return "Tecmo";
			(0x9C): return "Imagineer";
			(0x9F): return "Nova";
			(0xA1): return "Hori Electric";
			(0xA6): return "Kawada";
			(0xA7): return "Takara";
			(0xA9): return "Technos Japan";
			(0xAC): return "Toei Animation";
			(0xAD): return "Toho";
			(0xAF): return "Namco";
			(0xB1): return "ASCII or Nexsoft";
			(0xB4): return "Square Enix";
			(0xB6): return "HAL Laboratory";
			(0xB7): return "SNK";
			(0xB9 | 0xCE): return "Pony Canyon";
			(0xBA): return "Culture Brain";
			(0xBB): return "Sunsoft";
			(0xBD): return "Sony Imagesoft";
			(0xBF): return "Sammy";
			(0xC0 | 0xD0): return "Taito";
			(0xC3): return "Squaresoft";
			(0xC5): return "Data East";
			(0xC6): return "Tonkinhouse";
			(0xC8): return "Koei";
			(0xC9): return "UFL";
			(0xCA): return "Ultra";
			(0xCB): return "Vap";
			(0xCC): return "Use Corporation";
			(0xCD): return "Meldac";
			(0xD1): return "Sofel";
			(0xD2): return "Quest";
			(0xD3): return "Sigma Enterprises";
			(0xD4): return "ASK Kodansha Co.";
			(0xD7): return "Copya System";
			(0xDA): return "Tomy";
			(0xDD): return "NCS";
			(0xDE): return "Human";
			(0xDF): return "Altron";
			(0xE1): return "Towa Chiki";
			(0xE2): return "Yutaka";
			(0xE3): return "Varie";
			(0xE5): return "Epoch";
			(0xE7): return "Athena";
			(0xE8): return "Asmik";
			(0xE9): return "Natsume";
			(0xEA): return "King Records";
			(0xEC): return "Epic/Sony Records";
			(0xEE): return "IGS";
			(0xF0): return "A Wave";
			(0xF3): return "Extreme Entertainment";
		}
		return "Unknown Licensee";
	};

	fn new_licensee_code(str a) {
		if (std::mem::read_unsigned(0x14B, 1) != 0x33) return "See old licensee code";
		match(a) {
			("00"): return "None";
			("01"): return "Nintendo R&D1";
			("08"): return "Capcom";
			("13"): return "Electronic Arts";
			("18"): return "Hudson Soft";
			("19"): return "b-ai";
			("20"): return "KSS";
			("22"): return "pow";
			("24"): return "PCM Complete";
			("25"): return "san-x";
			("28"): return "Kemco Japan";
			("29"): return "seta";
			("30"): return "Viacom";
			("31"): return "Nintendo";
			("32"): return "Bandai";
			("33"): return "Ocean/Acclaim";
			("34"): return "Konami";
			("35"): return "Hector";
			("37"): return "Taito";
			("38"): return "Hudson";
			("39"): return "Banpresto";
			("41"): return "Ubi Soft";
			("42"): return "Atlus";
			("44"): return "Malibu";
			("46"): return "Angel";
			("47"): return "Bullet-Proof Software";
			("49"): return "irem";
			("50"): return "Absolute";
			("51"): return "Acclaim";
			("52"): return "Activision";
			("53"): return "American Sammy";
			("54"): return "Konami";
			("55"): return "Hi tech entertainment";
			("56"): return "LJN";
			("57"): return "Matchbox";
			("58"): return "Mattel";
			("59"): return "Milton Bradley";
			("60"): return "Titus";
			("61"): return "Virgin";
			("64"): return "LucasArts";
			("67"): return "Ocean";
			("69"): return "Electronic Arts";
			("70"): return "Infogrames";
			("71"): return "Interplay";
			("72"): return "Broderbund";
			("73"): return "sculptured";
			("75"): return "sci";
			("78"): return "THQ";
			("79"): return "Accolade";
			("80"): return "misawa";
			("83"): return "lozc";
			("86"): return "Tokuma Shoten Intermedia";
			("87"): return "Tsukuda Original";
			("91"): return "Chunksoft";
			("92"): return "Video system";
			("93"): return "Ocean/Acclaim";
			("95"): return "Varie";
			("96"): return "Yonezawa/s’pal";
			("97"): return "Kaneko";
			("99"): return "Pack in soft";
			("9H"): return "Bottom Up";
			("A4"): return "Konami (Yu-Gi-Oh!)";
			("BL"): return "MTO";
			("DK"): return "Kodansha";
		}
		return "Unknown";
	};

	using CGB;

	fn null_cgb_flags(CGB flags) {
		return "NO_CGB";
	};
}

enum DestinationType : u8 {
	Japanese,
	NonJapanese
};

enum SGBFlagType : u8 {
	NoSGBFunctionality,
	SGBFunctionality = 0x03
};

struct Header {
	char title[16-(std::mem::read_unsigned(addressof(this)+15, 1) >= 0x80)];
	if (std::mem::read_unsigned(addressof(this)+15, 1) == 0)
		CGB gbcFlags @ $-1 [[format("format::null_cgb_flags")]];
	else if (std::mem::read_unsigned(addressof(this)+15, 1) >= 0x80)
		CGB gbcFlags;
	char newLicenseeCode[2] [[format("format::new_licensee_code")]];
	SGBFlagType sgbFlag;
	u8 romType [[format("format::rom_features")]];
	u8 cartSize [[format("format::cart_size")]];
	u8 ramType [[format("format::ram_type")]];
	DestinationType destination;
	u8 licenseeCode [[format("format::licensee_code")]];
	u8 maskROMVersionNumber;
	u8 headerChecksum [[comment("Checksum for: $134-$14C")]];
	u16 globalChecksum [[comment("Checksum for entire range")]];
};

bitfield pixel_packed {
	p1 : 1;
	p2 : 1;
	p3 : 1;
	p4 : 1;
	p5 : 1;
	p6 : 1;
	p7 : 1;
	p8 : 1;
};

struct CartridgeStart {
	u8 entryCode[4];
	pixel_packed logo[0x30];
	Header header;
};

struct JumpVectors {
	u8 rst1[8] [[comment("rst $1")]];
	u8 rst2[8] [[comment("rst $2")]];
	u8 rst3[8] [[comment("rst $3")]];
	u8 rst4[8] [[comment("rst $4")]];
	u8 rst5[8] [[comment("rst $5")]];
	u8 rst6[8] [[comment("rst $6")]];
	u8 rst7[8] [[comment("rst $7")]];
	u8 rst8[8] [[comment("rst $8")]];
	u8 int1[8] [[comment("vblank")]];
	u8 int2[8] [[comment("lcd stat")]];
	u8 int3[8] [[comment("timer")]];
	u8 int4[8] [[comment("serial")]];
	u8 int5[8] [[comment("joypad")]];
};

struct romBank16K {
    u8 Bank[ROMBANKSIZE_16K];
};
struct romBank32K {
    u8 Bank[ROMBANKSIZE_32K];
};

romBank16K romBanks16K[std::mem::size() / ROMBANKSIZE_16K] @ 0x00;
romBank32K romBanks32K[std::mem::size() / ROMBANKSIZE_32K] @ 0x00;

JumpVectors jumpVectors @ 0x00 [[comment("Instructions called on interrupts or RST instructions")]];
CartridgeStart cartridgeStart @ 0x100;