// Supplemental read functions.
// Authors: unknown guy, Kaens (TG @kaens)
// Lots of legacy,
// TODO update the old scripts to use the new functions,
// and get rid of the functions themselves
/* beautify ignore:start */

var _BE = true, _LE = false; //endianness for read_int16+
//little-endian = reversed notation (Intel, ZX Spectrum),
//big-endian = direct notation (TCP/IP, Motorola, Amiga)
//For the BitReader Object, BE is MSB and LE is LSB (intuitively)
var CS_ALL = true, CS_BEST = false; //charStat needall 
var TOEOF = -1; //use for the size parameter in findSignature

// ---------- START OF PRE-v3.06 CODE --------------------

/**
 * Read a big-endian word.
 * @param {UInt} nOffset - The offset in the file.
 * @returns {UShort} The word value.
 * @alias Binary.readBEWord
 */
File.readBEWord = function(nOffset) { return X.U16(nOffset,_BE) }

/**
 * Read a big-endian dword.
 * @param {UInt} nOffset - The offset in the file.
 * @returns {UInt} The dword value.
 * @alias Binary.readBEDword
 */
File.readBEDword = function(nOffset) { return X.U32(nOffset,_BE) }

/**
 * Read a word, selecting endianness.
 * @param {UInt} nOffset - The offset in the file.
 * @param {Bool} bBE - True for big-endian.
 * @returns {UShort} The word value.
 * @alias Binary.readEWord
 */
File.readEWord = function(nOffset,bBE) { return X.U16(nOffset,bBE) }

/**
 * Read a dword, selecting endianness.
 * @param {UInt} nOffset - The offset in the file.
 * @param {Bool} bBE - True for big-endian.
 * @returns {UInt} The dword value.
 * @alias Binary.readEDWord
 */
File.readEDword = function(nOffset,bBE) { return X.U16(nOffset,bBE) }

/**
 * Read a short (signed 16-bit) value.
 * @param {UInt} nOffset - The offset in the file.
 * @returns {Short} The short value.
 * @alias Binary.readShort
 */
File.readShort = function(nOffset) { return X.I16(nOffset,_LE) }


// -------- END OF PRE-v3.06 CODE

// The encoding tables start with 7F, not 80! 7F is undefined in many charsets but it's good to have something
// The N(on)B(reakable)SP(ace) and S(oft)HY(phen) are kept as actual A0 and AD characters in this file 
const CP437 = "⌂"+
	"ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜ¢£¥₧ƒ"+
	"áíóúñÑªº¿⌐¬½¼¡«»░▒▓│┤╡╢╖╕╣║╗╝╜╛┐"+
	"└┴┬├─┼╞╟╚╔╩╦╠═╬╧╨╤╥╙╘╒╓╫╪┘┌█▄▌▐▀"+
	"αßΓπΣσµτΦΘΩδ∞φε∩≡±≥≤⌠⌡÷≈°∙·√ⁿ²■ ";
const CP866 = "⌂"+ //DOS Cyrillic
	'АБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ'+
	'абвгдежзийклмноп░▒▓│┤╡╢╖╕╣║╗╝╜╛┐'+
	'└┴┬├─┼╞╟╚╔╩╦╠═╬╧╨╤╥╙╘╒╓╫╪┘┌█▄▌▐▀'+
	'рстуфхцчшщъыьэюяЁёЄєЇїЎў°∙·√№¤■ ';
const CP1251 = "⌂"+
	"ЂЃ‚ѓ„…†‡€‰Љ‹ЊЌЋЏђ‘’“”•–—・™љ›њќћџ"+
	" ЎўЈ¤Ґ¦§Ё©Є«¬­®Ї°±Ііґµ¶·ё№є»јЅѕї"+
	"АБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ"+
	"абвгдежзийклмнопрстуфхцчшщъыьэюя";
const CP1252 = "⌂"+ //aka. Western aka. ISO-8859-1
	"€・‚ƒ„…†‡ˆ‰Š‹Œ・Ž・・‘’“”•–—˜™š›œ・žŸ"+
	" ¡¢£¤¥¦§¨©ª«¬・®¯°±²³´µ¶·¸¹º»¼½¾¿"+
	"ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞß"+
	"àáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";
const KOI8R = "⌂"+ //aka. RFC 1489, Morse code based
	'─│┌┐└┘├┤┬┴┼▀▄█▌▐░▒▓⌠■∙√≈≤≥ ⌡°²·÷'+
	'═║╒ё╓╔╕╖╗╘╙╚╛╜╝╞╟╠╡Ё╢╣╤╥╦╧╨╩╪╫╬©'+
	'юабцдефгхийклмнопярстужвьызшэщчъ'+
	'ЮАБЦДЕФГХИЙКЛМНОПЯРСТУЖВЬЫЗШЭЩЧЪ';
const JISX0201 = "⌂"+
	"→-‚ƒ„…†‡ˆ‰Š‹Œ↑Ž³™‘’“”•–—˜™š›œ¢žŸ"+ //decided to mix it with cp1252
	"→｡｢｣､･ｦｧｨｩｪｫｬｭｮｯｰｱｲｳｴｶｷｸｹｺｻｼｽｾｿﾀ"+
	"ﾁﾂﾃﾄﾅﾆﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝﾞﾟ"+
	"àáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";
const CPAmiga = "⫽"+ // alternatively, "▒""
	"абвгдежзийклмнопрстуфхцчшщъыьэюя"+ //0x80~0xA0 display Cyrillics, just to fill the void
	" ¡¢£¤¥¦§¨©ª«¬–®¯°±²³´µ¶·¸¹º»¼½¾¿"+
	"ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞß"+
	"àáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";
const CPRISCOS = "⌂"+
	"€Ŵŵ◰﯀Ŷŷ�⇦⇨⇩⇧…™‰•‘’‹›“”„–—−Œœ†‡ﬁﬂ"+
	" ¡¢£¤¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿"+
	"ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞß"+
	"àáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";
const CPAtariST = "⌂"+
	"ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜ¢£¥ßƒ"+
	"áíóúñÑªº¿⌐¬½¼¡«»ãõØøœŒÀÃÕ¨´†¶©®™"+
	"ĳĲאבגדהוזחטיכלמנסעפצקרשתןךםףץ§∧∞"+
	"αβΓπΣσµτΦΘΩδ∮φ∈∩≡±≥≤⌠⌡÷≈°∙·√ⁿ²³¯";
const CPSpeccy = ['©', //too SPECIAL with all the tokens-for-characters, gotta use lists
	'  ',' ▀','▀ ','▀▀',' ▄',' █','▀▄','▄█', '▄ ','▄▀','█ ','█▀','▄▄','▄█','█▄','██', //80~F
	'𝘼','𝘽','𝘾','𝘿','𝙀','𝙁','𝙂','𝙃','𝙄','𝙅','𝙆','𝙇','𝙈','𝙉','𝙊','𝙋', //90~F
	'𝙌','𝙍','𝙎','𝚉𝚇¹²⁸','⏯️','𝚁𝙽𝙳','𝙸𝙽𝙺𝙴𝚈$','π', '𝙵𝙽 ','𝙿𝙾𝙸𝙽𝚃 ','𝚂𝙲𝚁𝙴𝙴𝙽$ ','𝙰𝚃𝚃𝚁 ','𝙰𝚃 ','𝚃𝙰𝙱 ','𝚅𝙰𝙻$ ','𝙲𝙾𝙳𝙴' , //A0~F
	'𝚅𝙰𝙻 ','𝙻𝙴𝙽 ','𝚂𝙸𝙽 ','𝙲𝙾𝚂 ','𝚃𝙰𝙽 ','𝙰𝚂𝙽 ','𝙰𝙲𝚂 ','𝙰𝚃𝙽 ', '𝙻𝙽 ','𝙴𝚇𝙿 ','𝙸𝙽𝚃 ','𝚂𝚀𝚁 ','𝚂𝙶𝙽 ','𝙰𝙱𝚂 ','𝙿𝙴𝙴𝙺 ','𝙸𝙽 ', //B0~F
	'𝚄𝚂𝚁 ','𝚂𝚃𝚁$ ','𝙲𝙷𝚁$ ','𝙽𝙾𝚃 ','𝙱𝙸𝙽 ','𝙾𝚁 ','𝙰𝙽𝙳 ','≤', '≥','≠','𝙻𝙸𝙽𝙴 ','𝚃𝙷𝙴𝙽 ','𝚃𝙾 ','𝚂𝚃𝙴𝙿 ','𝙳𝙴𝙵 𝙵𝙽 ','𝙲𝙰𝚃 ', //C0~F
	'𝙵𝙾𝚁𝙼𝙰𝚃 ','𝙼𝙾𝚅𝙴 ','𝙴𝚁𝙰𝚂𝙴 ','𝙾𝙿𝙴𝙽 # ','𝙲𝙻𝙾𝚂𝙴 # ','𝙼𝙴𝚁𝙶𝙴 ','𝚅𝙴𝚁𝙸𝙵𝚈 ', '𝙱𝙴𝙴𝙿 ','𝙲𝙸𝚁𝙲𝙻𝙴 ','𝙸𝙽𝙺 ','𝙿𝙰𝙿𝙴𝚁 ','𝙵𝙻𝙰𝚂𝙷 ','𝙱𝚁𝙸𝙶𝙷𝚃 ','𝙸𝙽𝚅𝙴𝚁𝚂𝙴 ','𝙾𝚅𝙴𝚁 ','𝙾𝚄𝚃 ', //D0~F
	'𝙻𝙿𝚁𝙸𝙽𝚃 ','𝙻𝙻𝙸𝚂𝚃 ','𝚂𝚃𝙾𝙿 ','𝚁𝙴𝙰𝙳 ','𝙳𝙰𝚃𝙰 ','𝚁𝙴𝚂𝚃𝙾𝚁𝙴 ','𝙽𝙴𝚆 ', '𝙱𝙾𝚁𝙳𝙴𝚁 ','𝙲𝙾𝙽𝚃𝙸𝙽𝚄𝙴 ','𝙳𝙸𝙼 ','𝚁𝙴𝙼 ','𝙵𝙾𝚁 ','𝙶𝙾 𝚃𝙾 ','𝙶𝙾 𝚂𝚄𝙱 ','𝙸𝙽𝙿𝚄𝚃 ','𝙻𝙾𝙰𝙳 ', //E0~F
	'𝙻𝙸𝚂𝚃 ','𝙻𝙴𝚃 ','𝙿𝙰𝚄𝚂𝙴 ','𝙽𝙴𝚇𝚃 ','𝙿𝙾𝙺𝙴 ','𝙿𝚁𝙸𝙽𝚃 ','𝙿𝙻𝙾𝚃 ', '𝚁𝚄𝙽 ','𝚂𝙰𝚅𝙴 ','𝚁𝙰𝙽𝙳𝙾𝙼𝙸𝚉𝙴 ','𝙸𝙵 ','𝙲𝙻𝚂','𝙳𝚁𝙰𝚆 ','𝙲𝙻𝙴𝙰𝚁 ','𝚁𝙴𝚃𝚄𝚁𝙽', '𝙲𝙾𝙿𝚈']; //F0~F
const Chars0to1F = "・☺☻♥♦♣♠•◘○◙♂♀♪♫☼►◄↕‼¶§▬↨↑↓→←∟↔▲▼"; //#0 is a small dot from Japanese
const Chars0to1FLF = "・☺☻♥♦♣♠•◘○\x0A♂♀♪♫☼►◄↕‼¶§▬↨↑↓→←∟↔▲▼";
const Chars0to1FCRLF = "・☺☻♥♦♣♠•◘○\x0A♂♀\x0D♫☼►◄↕‼¶§▬↨↑↓→←∟↔▲▼";
const Chars0to1FSpeccy = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F"; //not mixing... // emit errors on the latest js

/**
 * Decode a 1-byte encoding from a byte array using the 128-byte-long table given,
 * as well as a table to display the first 32 characters.
 * @param {[uint8]} ansi - an array returned by readBytes.
 * @param {String[0x81]} dectbl - a decoding table; just make a const here in db/read for that
 * @param {bool} zstop (optional, default=true) - whether to stop reading on 0 (ASCIIZ behaviour)
 * @param {Array} tbl01F (optional, default=Chars0to1FCRLF) - which table to use for the first 32 characters
 * @returns {String} a string value usable with js.
 */
function decEncoding(ansi, dectbl, zstop, tbl01F) {
	if(typeof zstop === 'undefined') zstop = true;
	if(typeof tbl01F === 'undefined')
		if(dectbl == CPSpeccy) tbl01F = Chars0to1FSpeccy;
		else tbl01F = Chars0to1FCRLF;
	var s = "", bit8 = 0;
	for(var i=0; i < ansi.length; i++) {
		if (!ansi[i] && zstop) break;
		else if(ansi[i] < 0x80)
			switch(ansi[i]) { // 7-bit variation processing
			case 0x0E: if(dectbl == JISX0201 || dectbl == KOI8R) bit8 = 0x80;
				else s += tbl01F[0xE]; break;
			case 0x0F: if(dectbl == JISX0201 || dectbl == KOI8R) bit8 = 0;
				else s += tbl01F[0xF]; break;
			case 0x5C: if(dectbl == JISX0201) s += "¥"; else s += "\\"; break;
			case 0x5E: if(dectbl == CPSpeccy) s += '↑'; else s += '^'; break;
			case 0x60: if(dectbl == CPSpeccy) s += '£'; else s += '`'; break;
			case 0x7E: if(dectbl == JISX0201) s += "‾"; else s += "~"; break;
			case 0x7F:
				if(dectbl != JISX0201) s += dectbl[0];
				else s += String.fromCharCode(bit8+ansi[i]); break;
			default:
				if(!bit8 && ansi[i] >= 0 && ansi[i] < 0x20) s += tbl01F[ansi[i]];
				else s += String.fromCharCode(bit8+ansi[i]);
			}
		else s += dectbl[ansi[i]-0x7F];
	}
	return s;
}

/**
 * Read a byte array from file.
 * @param {UInt} ofs - the offset to start from.
 * @param {Int} len - the amount of bytes to read.
 * @param {Bool} zspace (optional, default=false) - replace 0 with 0x20 (space characters).
 * @returns {[uint8]} The file slice. If you go beyond EoF, read_uint8 only knows what happens.
 */
function readBytes(ofs, len, zspace) { //for now; feels like this should be a system function
	var c, s = []; if(typeof zspace === 'undefined') zspace = false;
	for (var i=0; i < len && ofs+i < File.getSize(); i++) {
		c = File.read_uint8(ofs+i);
		if(zspace && !c) c = 0x20;
		s.push(c);
	}
	return s;
}

/**
 * Decode a 1-byte encoding from file using the 128-byte-long table given.
 * @param {UInt} ofs - the offset to start from.
 * @param {UInt} len - the amount of bytes to read.
 * @param {String[0x81]} dectbl - a decoding table; just make a const here in db/read for that
 * @param {bool} zstop (optional, default=true) - whether to stop reading on 0 (ASCIIZ behaviour)
 * @param {Array} tbl01F (optional, default=Chars0to1FCRLF) - which table to use for the first 32 characters
 * @returns {String} a string value usable with js.
 */
function decAnsi(ofs, len, dectbl, zstop, tbl01F) {
	return(decEncoding(readBytes(ofs,len), dectbl, zstop, tbl01F))
}


/**
 * Checks for whether a value fits the limits using <=, as opposed to isInside.
 * @param {Number} a - the value to check.
 * @param {Number} mina
 * @param {Number} maxa
 * @returns {Bool}
 */
function isWithin(a, mina, maxa) {
	return mina <= a && a <= maxa
}

/**
 * Checks for whether a value fits the limits using <, as opposed to isWithin. Useful for floats.
 * @param {Number} a - the value to check.
 * @param {Number} mina
 * @param {Number} maxa
 * @returns {Bool}
 */
function isInside(a, mina, maxa) {
	return mina < a && a < maxa
}

/**
 * Derive a string hexadecimal value, zero-padded.
 * @param {Int} a - the numerical value.
 * @param {UInt} padz (optional,default=2) - how many characters to zero-pad.
 * @returns {String} The hex value, capital letters A~F, ending with "h".
 */
function Hex(a, padz) {
	if(typeof a === 'undefined') return "!Hex("+a+")";
	if(typeof padz === 'undefined') padz = 2;
	var minus=""; if(a<0) { a = -a; minus = "-" }
	var r = a.toString(16).toUpperCase(); var pads="";
	if(r.length < padz) pads = Array(1 + padz - r.length).join('0');
	return minus+pads+r+"h"
}

function Bin(a, padz) {
	if(typeof a === 'undefined') return "!Bin("+a+")";
	if(typeof padz === 'undefined') padz = 4;
	var minus = ""; if(a < 0) { a = -a; minus = "-" }
	var r = a.toString(2); var pads="";
	if(r.length < padz) pads = Array(1 + padz - r.length).join('0');
	return minus+pads+r+"b"
}

function Oct(a, padz) {
	if(typeof a === 'undefined') return "!Oct("+a+")";
	if(typeof padz === 'undefined') padz = 3;
	var minus = ""; if(a < 0) { a = -a; minus = "-" }
	var r = a.toString(8); var pads="";
	if(r.length < padz) pads = Array(1 + padz - r.length).join('0');
	return minus+pads+r+"o"
}

/**
 * Read a variable-length quantity, an unsigned integer like in MIDI files, from the file.
 * @param {UInt} ofs - the offset to start from.
 * @returns {List} [length,value] - if length (in physical bytes) = 0, the value had a problem.
**/
function readVarUInt(ofs) {
	if(ofs < 0 || ofs >= File.getSize()) return [0,0];
	var t = 0, wb = 1, r = 1, o = ofs;
	var b = File.read_uint8(o++); t = (t << 7) | (b&0x7F);
	var b_ = b; while(b_) { b_ >>= 1; wb++ }
	while(r < 16 && (b&0x80)) {
		b = File.read_uint8(o++); t = (t << 7) | (b&0x7F); r++
	}
	if(wb > 64) return [0,0xFFFFFFFFFFFFFFFF]; // sizeof(target) in bits. A 64bit value should be enough, right?
	else if(b&0x80) return [0,-1]; //EOF
	else return [r,t]
}

/**
 * This object facilitates reading a file as a sequence of bits
 * @init {UInt} [nOffset = 0] - provide the file offset
 * @param {UInt} nBits - bits to read, autolimits to 32 (so read little by little!)
 * @returns {UInt} read value as integer, -1 if EoF reached
 * @example
 * First create an instance with the file object: var bits = new BitReader(10);
 * Then call the readBits method with the number of bits you want: var value = bits.read(5)
 * Or put the reader towards a different place: bits.init(10)
 * Receive the current bit-file offset: bits.offset
 * Set the bit-file's offset, in bytes, without changing state: bits.seek(10)
 * Set the bit-file's offset in bits: bits.bseek(14)
 * Skip some bytes without changing state: bits.consume(2)
**/
function BitReader(nOffset, nEndian) {
	this.n = 0; // the number of bits in the buffer
	this.buf = 0; // the bit buffer
	this.offset = nOffset ? nOffset : 0; // the file offset
	this.endian = nEndian ? nEndian : _LE; // for different mechanics of bitstreaming; ogg/flac use _BE

	// use this to change the pointer, which will reinit the reader, but not the logger
	this.init = function(nOffset) { this.ofs = nOffset ? nOffset : 0; this.n = this.buf = 0 }

	// the method to read b bits from the file
	this.read = function(nBits) {
		if(nBits > 64) nBits = 64; if(nBits < 0) return 0;
		if(this.endian === _LE) {
			while(this.n < nBits) { // while the buffer is not enough
				this.buf |= Util.shlu64(File.read_uint8(this.offset++),this.n); // read a byte and append it to the buffer
				this.n += 8; // increase the bit number by 8
			}
			var v = this.buf & (Util.shlu64(1,nBits) - 1); // extract the desired bits from the buffer
			this.buf = Util.shru64(this.buf,nBits); // shift the buffer to the right
		} else {
			while(this.n < nBits) {
				this.buf = Util.shlu64(this.buf,8) | File.read_uint8(this.offset++); // shift the buffer to the left and append a byte
				this.n += 8;
			}
			var v = Util.shru64(this.buf,this.n - nBits); // extract the desired bits from the most significant part of the buffer
			this.buf &= Util.shru64((Util.shlu64(1,this.n)-1),nBits); // clear the extracted bits from the buffer
		}
		this.n -= nBits; // decrease the bit number by b
		return v; // return the value even if the file is exhausted
	}

	// Skip some bytes without changing state: bits.consume(2)
	this.consume = function(nBytes) { this.offset += nBytes; }

	// Set the bit-file's offset, in bytes, without changing state:
	this.seek = function(nOfs) { this.offset = nOfs; }

	// Set the bit-file's offset in bits:
	this.bseek = function(nOfs) { this.offset = nOfs - (nOfs%8); this.buf = this.n = 0; this.read(nOfs%8); }
}

/**
 * Check a file slice for being all one of a lineup of specified characters.
 * @param {UInt} ofs - the offset to start from.
 * @param {UInt} len - the amount of bytes to check.
 * @param {[Array(UInt)] | UInt} bl = [0] - the list of possible u_int8 codes, or just one u_int8. 0 by default.
 * @returns {UInt} - offset if a byte in the slice doesn't belong to the list. If you go beyond EoF or all good, -1.
 * @example
 * For '00 01 02 01' at offset 6, firstNotOf (6, 4, [0,1]) === 8, and firstNotOf(6, 4, 1) === 6
 */
function firstNotOf(ofs, len, bl) {
	if(ofs+len > X.Sz()) return -1; var c = i = 0;
	if(Array.isArray(bl)) {
		for(i = 0; i < bl.length; i++) if(typeof bl[i] !== 'number' || bl[i] < 0 || bl[i] % 1 != 0) break; 
		if(i < bl.length) throw new Error('firstNotOf cannot parse: '+outArray(bl));
	}
	else if(typeof bl === 'number' && bl > 0 && bl % 1 == 0) bl = [bl]; else bl = [0];
	// and now test the slice
	for(i = 0; i < len && ofs+i < X.Sz(); i++) if(bl.indexOf(X.U8(ofs+i)) < 0) break;
	return i < len? ofs+i : -1
}

function isAllZeroes(ofs, len) { return firstNotOf(ofs, len, 0) < 0 } //a subcase for whether a slice is all zeroes 

/**
 * If the string was too long and has been read incompletely, adds an ellipsis after the last
 * complete word, to avoid cut-off words. If `space characters' are not detected,
 * replaces the last character with an ellipsis. Does NOT do the trim().
 * Mostly usable for lengthy multiline comments/messages.
 * @param {String} a - the original incomplete string.
 * @param {Number} trim - the buffer size; if a.length == trim, we decide it was cropped.
 * @param {Number} [mintrim = 78] - don't try searching for spaces below this point.
 * @returns {String} - the resulting string.
 */
function addEllipsis(a, trim, mintrim) {
	if(!trim) trim = 0xA0;
	if(!mintrim) mintrim = 78; if(a.length < trim || mintrim > trim) return a.trim();
	const spaces = " .,:;!\\/'\"=&\x09\x0D\x0A\x1A\x26。、｡,，・";
	var i = trim, c = 0, ci = -1;
	while(i >= mintrim && c < 2) {
		if(spaces.indexOf(a[i]) >= 0) { c++; while(spaces.indexOf(a[i]) >= 0) i--; if(ci < 0) ci = i+1 }
		while(spaces.indexOf(a[i]) < 0 && i >= 0) i--
	}
	if((i < mintrim && c < 2) //we conclude this language doesn't really have that many spaces...
	  || !c) //...or none at all in the trimmable slice...
		return a.slice(0,trim)+'…';
	else //this language has some spaces and we can use the last one to trim
		return a.slice(0,Math.max(ci),mintrim)+'…';
}

/**
 * sOptions.append a string (optionally prefixed) if the space-trimmed string is not empty.
 * @param {variant} a - the string to output (safe to accidentally drop a non-string in)
 * @param {String} prefix (optional) - what to put in front of the output string
 * @param {String} suffix (optional) - what to put after the output string
 */
function sOptionT(a, prefix, suffix) {
  if (typeof prefix === 'undefined') prefix = ""; if (typeof suffix === 'undefined') suffix = "";
  if ((""+a).trim() != "") sOptions = sOptions.append(prefix+(""+a).trim()+suffix)
}

/**
 * sOptions.append a string (optionally prefixed) if the string is not empty.
 * @param {variant} a - the string to output (safe to accidentally drop a non-string in)
 * @param {String} prefix (optional) - what to put in front of the output string
 * @param {String} suffix (optional) - what to put after the output string
 */
function sOption(a, prefix, suffix) {
  if (typeof prefix === 'undefined') prefix = ""; if (typeof suffix === 'undefined') suffix = "";
  if ((""+a).trim() != "") sOptions = sOptions.append(prefix+(""+a).trim()+suffix)
}

/**
 * A more verbose (but still concise) way of outputting the calculated size(s, derived using different algorithms),
 * taking into account and visualising the difference from the actual file size.
 * @param {...Number} sizes - numerical values
 * For example, if a file is 100 bytes long, outSz(90,100,105) will yield "90(+10)/100/105(-5!)"
 * The "!)" thus indicates the file is too short compared to the algorithmic estimation.
 * If some of the reported sizes match, the value will only be displayed once.
 * It's still a good idea to add "/malformed!short" to the version string — it's visible without isVerbose.
 */
function outSz() { if(!arguments.length || typeof arguments[0] === 'undefined') return "?";
	var sizes = [], origs = [];
	for(i = 0; i < arguments.length; i++)
	  if(arguments[i] >= 0) if(!origs.length || origs.indexOf(arguments[i]) < 0) {
		origs.push(arguments[i]);
		sizes.push(
			arguments[i] < File.getSize() ? arguments[i]+"(+"+(File.getSize()-arguments[i])+")"
		  : arguments[i] > File.getSize() ? arguments[i]+"(-"+(arguments[i]-File.getSize())+"!)"
		  : arguments[i]
		)
	  } else; else sizes.push("?");
	return sizes.join("/")
}

/**
 * Converts an array to a better-looking line than the usual flat thing DiE's _log would output.
 * @param {Array} a - Array to process consisting of any information including arrays
 * @param {Int = 10} base - If an integer value is found, in which base to display it
 * @param {Int} zeropad - If an integer value is found, how many zeroes to pad it with (smart by default)
 * @returns {String} A beautiful output!
 * Ex. 𝑓([ 1, [5, [10,30]], [[23],'test'] ], 2) = "[0001, [0101, [1010, 11110]], [[10111], test]]"
 * Ex. 𝑓([ 1, [5, [10,30]], [[23],'test'] ], 16) = "[01, [05, [0A, 1E]], [[17], test]]"
 */
function outArray(a,base,pad) {
	if(!Array.isArray(a)) return a;
	if(typeof base !== 'number' || base % 1 !== 0) base = 10;
	if(typeof pad !== 'number' || pad % 1 !== 0) //not integer
		if(typeof pad === 'undefined')
			if(base == 8) pad = 3; else if(base == 16) pad = 2; else if(base == 2) pad = 4; else pad = 0;
	for(var i=0, s = []; i < a.length; i++)
		if(Array.isArray(a[i])) s.push(outArray(a[i],base,pad)); else
			if(typeof a[i] === 'number' && a[i] % 1 === 0) //integer
				s.push(a[i].toString(base).toUpperCase().padStart(pad,'0'));
			else if(typeof a[i] === 'string') s.push('"'+a[i]+'"');
			else s.push(a[i]);
	return '['+s.join(', ')+']' //put '[ '...' ]' for an even more spaced output
}

/**
 * A shorthand for the situation where you compare the file suffix to what you'd expect. Use as the option to isHeuristicScan being true.
 * @param {String} a - the expected file suffix, case-insensitive, no heading period unlike Python
 * @returns {bool} if a match is reached
 */
function extIs(a) { return File.getFileSuffix().toLowerCase() == a.toLowerCase() }

/**
 * slashTag formats a string in a way that's useful when a tag has two versions (for ex. in different languages). It will either show both with "/" in between, or one of them if the other one's an empty string, or an empty string if both are empty.
 * @param {String} a - the first of the two
 * @param {String} b - the second of the two
 * @returns {String}
*/
function slashTag(a, b) {
	if(a == b) return a;
	else if(a != "" && b == "")
		return a;
	else if(a == "" && b != "")
		return b;
	else if(a != "" && b != "")
		return a+"/"+b;
	else return ""
}

/**
 * createOrderlyHuffmanTable is just for detections but it does return the table for further checks. Or it returns false.
 * @param {Array} lent - the lengths table
 * @param {String} btl - bit table length
 * @param {BitReader} br - a BitReader object pointing somewhere at the right position for this. The provided BitReader WILL change state.
 * @returns {Array or false}
*/
// createOrderlyHuffmanTable is just for detections but it does return the table for further checks. Or it returns false.
function createOrderlyHuffmanTable(lent, btl, br) {
	var md = 32, Md = reall = code = 0; var _t = [], fi = [], li = [], ni = [];
	for(i = 0; i < 33; i++) fi[i] = 0xFFFF;
	for(i = 0; i < btl; i++) { len = lent[i]; if(len) {
		if(len < md) md = len; if(len > Md) Md = len;
		if(fi[len] == 0xFFFF) { fi[len] = li[len] = i } else { ni[li[len]] = i; li[len] = i } reall++ } }
	if(!Md) return false;
	for(d = md; d <= Md; d++) {
		if(fi[d] != 0xFFFF) ni[li[d]] = btl;
		for(i = fi[d]; i < btl; i = ni[i]) {
			//insert HuffmanCode:
			var j = 0, le = _t.length;
			for(var cb = d; cb >= 0; cb--) {
				var cob = (cb && ( ( (code>>(Md-d)) >> (cb-1) ) & 1 ) ) ? 1 : 0;
				if(j != le) {
					if(!cb || (!_t[j][0] && !_t[j][1])) return false; //[0] is left, [1] is right, [2] is value
					if(!_t[j][cob]) _t[j][cob] = j = le; else j = _t[j][cob];
				} else {
					_t.push([ (cb&&!cob)?le+1:0, (cb&&cob)?le+1:0, cb?0:i ]);
					j++; le++
				} }
			code += 1 << (Md-d) } }
	return _t
}

/**
 * Outputs time in seconds as short human-readable, with a "h:mm:ss" alternative when < 1 day.
 * Millenia, centuries and years a sidereal years, a "month" duration is 1/12 of such year.
 * @param {Number} seconds
 * @returns {String}
 * Ex. 𝑓(123456789) = "31Y10M4w21h33m9s"; 𝑓(1234567) = "2w6h56m7s"; 𝑓(12345) = "3:25:45"
 */
function secondsToTimeStr(s) {
	const mul = [/*millenia*/315581497635,/*centuries*/3155814976,/*yrs*/31558150,/*mns*/2629846,/*wks*/604800,86400,3600,60];
	var r = "", ss = s%mul[7], mm = Util.div64(s%mul[6],mul[7]), hh = Util.div64(s%mul[5],mul[6]),
	dd = Util.div64(s%mul[4],mul[5]), ww = Util.div64(s%mul[3],mul[4]), mn = Util.div64(s%mul[2],mul[3]),
	yy = Util.div64(s%mul[1],mul[2]), cc = Util.div64(s%mul[0],mul[1]), mi = Util.div64(s,mul[0]);
	if(s < 86400) { r = mm.padStart(2,'0')+":"+ss.padStart(2,'0'); if(hh) r = hh+":"+r; return r }
	if(ss) r = ss+"s"+r; if(mm) r = mm+"m"+r; if(hh) r = hh+"h"+r; if(dd) r = dd+"d"+r; if(ww) r = ww+"w"+r;
	if(mn) r = mn+"M"+r; if(yy) r = yy+"Y"+r; if(cc) r = cc+"C"+r; if(mi) r = ci+"Mil"+r; return r
}

/**
 * Examines a sequence and gives a generalised idea of what sort of characters a string is (mostly) made of.
 * Could be useful for validating structured files with human-filled fields.
 * @param {String/Number[]} s - your string in question, or a List of charcodes.
 * @param {Boolean=false} needall - if true, you have "allascallt allnum" for a line of spaces, else just "allt ".
 * @returns {String} - at least one or a combo of these, optional prefix "all" (otherwise "mostly"):
 *  '?': wrong type; 'empty': 0 length; '00': zeroes; 't ': tabs/spaces; 'ctl': 0-1Fh & 7Fh; 'num': numerical;
 *  'asc': 20h-7Eh; 'xsc': zeroes+tabs+♫+FFh+crlf+ascii; 'foreign': 00,t, ,crlf, 80h+; 'any': decision cannot be made.
 * Parse the result using indexOf.
 * Ex. 𝑓("-123 456.789") = "allnum", 𝑓("-123 456.789",1) = "allnumallascallxscallforeign"
 */
/* beautify preserve:start */
function charStat() {
	if(!arguments.length) return "?";
	if(typeof arguments[0] === "undefined" || typeof arguments[0] === "number") return "?";
	str = arguments[0];
	if(arguments.length < 2) needall = false; else needall = !!arguments[1];
	if(str == "" || str == []) return "empty";
	var i, s = [], c = [ /*[0]00*/0, /*[1]t */0, /*[2]asc*/0, /*[3]xsc*/0, /*[4]num*/0,
	  /*[5]ctl*/0, /*[6]foreign*/0 ], o = [0,0,0,0,0,0,0,0];
	if(typeof str === "string") for(i = 0; i < str.length; i++) s.push(str.charCodeAt(i)); else s = str;
	for(i=0;i<s.length;i++) {
		if(!s[i]) { c[0]++; c[3]++; c[5]++; c[6]++ }
		else if(s[i] == 9) { c[1]++; c[3]++; c[5]++; c[6]++ }
		else if(s[i] == 0xA || s[i] == 0xD) { c[3]++; c[5]++; c[6]++ }
		else if(s[i] == 0xE) { c[3]++; c[5]++ }
		else if(s[i] <= 0x1F || s[i] == 0x7F) c[5]++;
		else if(s[i] == 0x20) { c[1]++; c[2]++; c[3]++; c[4]++; c[6]++; }
		else if(0x2B <= s[i] && s[i] <= 0x2D || 0x30 <= s[i] && s[i] <= 0x39) { c[2]++; c[3]++; c[4]++; c[6]++ }
		else if(s[i] <= 0x7E) { c[2]++; c[3]++ }
		else if(s[i] == 0xFF) { c[3]++; c[6]++ }
		else if(s[i] > 0x7F) c[6]++
	} for(i = 0; i < c.length; i++) o[i] = Util.div64(c[i]*100,s.length);
	r = "";
	//_log((typeof str)+" "+s+" {"+c+"} <"+o+">")
	if(!needall) {
		if(o[0] > 70) { if(o[0] === 100) r += "all";  r += "00" }
		else if(o[1] > 70) { if(o[1] === 100) r += "all";  r += "t " }
		else if(o[4] > 70) { if(o[4] === 100) r += "all";  r += "num" }
		else if(o[2] > 70) { if(o[2] === 100) r += "all";  r += "asc" }
		else if(o[3] > 70) { if(o[3] === 100) r += "all";  r += "xsc" }
		else if(o[5] > 70) { if(o[5] === 100) r += "all";  r += "ctl" }
		else if(o[6] > 70) { if(o[6] === 100) r += "all";  r += "foreign" }
	} else {
		if(o[0] > 70) { if(o[0] === 100) r += "all";  r += "00" }
		if(o[1] > 70) { if(o[1] === 100) r += "all";  r += "t " }
		if(o[4] > 70) { if(o[4] === 100) r += "all";  r += "num" }
		if(o[2] > 70) { if(o[2] === 100) r += "all";  r += "asc" }
		if(o[3] > 70) { if(o[3] === 100) r += "all";  r += "xsc" }
		if(o[5] > 70) { if(o[5] === 100) r += "all";  r += "ctl" }
		if(o[6] > 70) { if(o[6] === 100) r += "all";  r += "foreign" }
	} 
	if(r == "") return "any"+o; else return r
}

// PATCHING FUNCTIONALITY; promised to become native
var patcheddata = [];
function rpU8(adr) { //read patched data or passthrough, U8
	for(var i=0; i < patcheddata.length; i++) if(patcheddata[i][0] == adr) return patcheddata[i][1];
	return X.U8(adr)
}
function rpU16be(adr) { //read patched data or passthrough, U16 BE
	return (rpU8(adr) << 8) | rpU8(adr+1)
}
function rpU32be(adr) { //read patched data or passthrough, U32 BE
	return (rpU8(adr) << 24) | (rpU8(adr+1) << 16) | (rpU8(adr+2) << 8) | rpU8(adr+3)
}
function wpU8(adr,val) { //add to patches, U8
	for(var i=0; i < patcheddata.length; i++)
		if(patcheddata[i][0] == adr) { patcheddata[i][1] = val; return }
	patcheddata.push([adr,val])
}
function wpU16be(adr,val) { //add to patches, U16 BE
	wpU8(adr,(val>>8)&0xFF); wpU8(adr+1,val&0xFF)
}
function wpU32be(adr,val) { //add to patches, U32 BE
	wpU8(adr,(val>>24)&0xFF); wpU8(adr+1,(val>>16)&0xFF);
	wpU8(adr+2,(val>>8)&0xFF); wpU8(adr+3,val&0xFF)
}
function patchLength() { return patcheddata.length }
function patchClear() { patcheddata = [] }

/**
 * Discovers gaps in an array of pairs of numbers, with a minimum-to-report gap as optional parameter.
 * @param {Array of arrays[2]} lst - List to process consisting of ranges defined as [offset,length]
 * @param {UInt = 1} mingap - Minimum gap, default to at least 1 byte between the ranges
 * @returns {Array of arrays[2]} Sorted list of gap ranges in the same format
 * Ex. 𝑓([ [10,10], [25,5], [40,10] ]) = [[20,5], [30,10]] 
 */
function findGaps(lst, mingap) {
	var i, r = []; /* tests for input typing follow */ if(!Array.isArray(lst) || lst.length < 2) return r;
	for(i = 0; i < lst.length; i++) if(!Array.isArray(lst[i]) || lst[i].length != 2
		|| typeof lst[i][0] !== 'number' || typeof lst[i][1] !== 'number') return r;
	if(typeof mingap !== 'number') mingap = 1;
	function sf(a, b) { if(a[0] != b[0]) return a[0]-b[0]; else return a[1]-b[1] }
	var a = lst.sort(sf);
	for(i = 1; i < a.length; i++)
		if((t=a[i-1][0]+a[i-1][1]) < a[i][0] && a[i][0]-mingap >= 0) r.push([t, a[i][0]-t])
	return r
}

/**
 * Discovers intersections in an array of pairs of numbers, considering all possible pairs.
 * @param {Array of arrays[2]} lst - List to process consisting of ranges defined as [offset,length]
 * @param {Boolean = false} detectone - Stop searching after finding even one intersection
 * @returns {Array of arrays[2]} Sorted list of intersection ranges in the same format; if length > 0, intersection present
 * Ex. 𝑓([ [10,20], [15,10], [23,30] ]) = [[15,10], [23,2], [23,7]]
 * Ex. 𝑓([ [10,20], [15,10], [23,30] ], true) = [[15,10]]
 */
function findIntersections(lst,detectone) {
	var i, t, r = []; /* tests for input typing follow */ if(!Array.isArray(lst) || lst.length < 2) return r;
	for(i=0; i < lst.length; i++) if(!Array.isArray(lst[i]) || lst[i].length != 2
		|| typeof lst[i][0] !== 'number' || typeof lst[i][1] !== 'number') return r;
	function sf(a, b) { if(a[0] != b[0]) return a[0]-b[0]; else return a[1]-b[1] }
	var a = lst.sort(sf); var found = false;
	for(i=1; i < a.length && !found; i++)
		for(j=0; j < i && !found; j++)
			if((t=a[j][0]+a[j][1]) > a[i][0]) { if(detectone) found = true;
//_log(' item#'+j+' ['+lst[j][0]+' -> '+lst[j][1]+'] intersects with item#'+i+' ['+lst[i][0]+' -> '+lst[i][1]+']')
				r.push([a[i][0], a[i][0]+a[i][1] <= t ? a[i][1] : t-a[i][0]])
			}
	return r.sort(sf);
}

b64Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
function toBase64(buf) {
	var r = '', i = 0, indexOfLastCompleteTriple = buf.length - (buf.length%3);
	for (i = 0; i < indexOfLastCompleteTriple; i += 3) {
		r += b64Chars[buf[i] >> 2];
		r += b64Chars[((buf[i] & 3) << 4) | ((buf[i+1] & 0xF0) >> 4)];
		r += b64Chars[((buf[i+1] & 0xF) << 2) | ((buf[i+2] & 0xC0) >> 6)];
		r += b64Chars[buf[i+2] & 0x3F]
	}
	if (i < buf.length) {
		var i1 = buf[i],  i2 = (i+1 < buf.length) ? buf[i+1] : 0;
		r += b64Chars[i1 >> 2];
		r += b64Chars[((i1 & 0x03) << 4) | ((i2 & 0xF0) >> 4)];
		if (i+1 < buf.length) {
			r += b64Chars[((i2 & 0x0F) << 2)];
		}
		else r += '=';
		r += '=';
	}
	return r
}

/**
 * If it's an Amiga hunk file, proceeds to process hunks
 * @returns {Int} -1 in case of errors, otherwise expected size
 */
function calcAmigaFileSize() {
	if(!X.c("000003F3")) return -1; //is it an Amiga hunk file?
	var p = 4, x = sz = i = reslibs = 0, sizes = [], load = true;
	//library strings:
	while(p < X.Sz()) {
		x = X.U32(4,_BE); p += 4; if(!reslibs && x) load = false; if(x) reslibs++; else break; p += 4*x
	}
	var hunks = X.U32(p+8,_BE) - X.U32(p+4,_BE) + 1; p += 12;
sOption(hunks+' hunks')
	//hunk table:
	for(i=0; i < hunks && p < X.Sz(); i++,p+=4) {
		var t = X.U32(p,_BE), add = (t>>30) == 3? 4: 0; t &= 0x3FFFFFFF; t <<= 2; t += add;
_log('@'+Hex(p)+' hunk#'+i+' = '+Hex(t));
		sizes.push(t); sz += t
	}
	//traverse hunks:
	sz += p; //if(sz >= X.Sz()) return -1;
	return sz
}

function _logBase64(buf) { //simply plops the buffer contents into log stream with a suitable MIME header
	var fn = File.getFileBaseName()+'.'+File.getFileCompleteSuffix();
	_log('MIME-Version: 1.0\nContent-Type: application/octet-stream; name="'+fn+'.dec"\n'+
	'Content-Transfer-Encoding: base64\nContent-Disposition: attachment; filename="'+fn+'.dec"\n');
	_log(buf)
}

function _logHex(buf) { //same but no header and in hex
	var o = ''; for(i=0; i < buf.length; i++) {
		if(!(i % 16)) o += (i? '  |\n': '')+i.toString(16).padStart(6,'0')+' |'; if(!(i % 8)) o += ' ';
		o += ' '+buf[i].toString(16).padStart(2,'0');
	}
	_log('-8<---'); _log(o); _log('--->8-')
}

function _logText(buf) { //same but as text put through CP866, or all file with zeroes as spaces and control characters as emoji
	_log('-8<---['+(typeof buf)+' '+(buf.length)+' bytes]---');
	if(typeof buf === 'object') {
		var bf = buf, i = 0; for(; i < buf.length; i++) if(bf[i] == 0) bf[i] = 0x20
	}
	_log(decEncoding((typeof buf === 'undefined'? readBytes(0,X.Sz(),true): bf), CP866, Chars0to1F));
	_log('--->8-')
}

function _l2r(name,pos,issue) { _setResult('debug',name,'@'+Hex(pos),issue); }
/* beautify ignore:end */