enigma-bbs/core/string_util.js

/* jslint node: true */
'use strict';

//	ENiGMA½
const miscUtil			= require('./misc_util.js');
const ANSIEscapeParser	= require('./ansi_escape_parser.js').ANSIEscapeParser;
const ANSI				= require('./ansi_term.js');

//	deps
const iconv				= require('iconv-lite');
const _					= require('lodash');

exports.stylizeString				= stylizeString;
exports.pad							= pad;
exports.insert						= insert;
exports.replaceAt					= replaceAt;
exports.isPrintable					= isPrintable;
exports.stripAllLineFeeds			= stripAllLineFeeds;
exports.debugEscapedString			= debugEscapedString;
exports.stringFromNullTermBuffer	= stringFromNullTermBuffer;
exports.stringToNullTermBuffer		= stringToNullTermBuffer;
exports.renderSubstr				= renderSubstr;
exports.renderStringLength			= renderStringLength;
exports.formatByteSizeAbbr			= formatByteSizeAbbr;
exports.formatByteSize				= formatByteSize;
exports.cleanControlCodes			= cleanControlCodes;
exports.isAnsi						= isAnsi;
exports.isAnsiLine					= isAnsiLine;
exports.isFormattedLine				= isFormattedLine;
exports.splitTextAtTerms			= splitTextAtTerms;

//	:TODO: create Unicode verison of this
const VOWELS = [ 'a', 'e', 'i', 'o', 'u' ];
VOWELS.concat(VOWELS.map(l => l.toUpperCase()));

const SIMPLE_ELITE_MAP = {
	'a' : '4',
	'e' : '3',
	'i' : '1',
	'o' : '0',
	's' : '5',
	't' : '7'
};

function stylizeString(s, style) {
	var len = s.length;
	var c;
	var i;
	var stylized = '';

	switch(style) {
		//	None/normal
		case 'normal' :
		case 'N' : 
			return s;

		//	UPPERCASE
		case 'upper' : 
		case 'U' : 
			return s.toUpperCase();

		//	lowercase
		case 'lower' :
		case 'l' :
			return s.toLowerCase();

		//	Title Case
		case 'title' :
		case 'T' :
			return s.replace(/\w\S*/g, function onProperCaseChar(t) {
				return t.charAt(0).toUpperCase() + t.substr(1).toLowerCase();
			});

		//	fIRST lOWER
		case 'first lower' :
		case 'f' :
			return s.replace(/\w\S*/g, function onFirstLowerChar(t) {
				return t.charAt(0).toLowerCase() + t.substr(1).toUpperCase();
			});

		//	SMaLL VoWeLS
		case 'small vowels' :
		case 'v' :
			for(i = 0; i < len; ++i) {
				c = s[i];
				if(-1 !== VOWELS.indexOf(c)) {
					stylized += c.toLowerCase();
				} else {
					stylized += c.toUpperCase();
				}
			}
			return stylized;

		//	bIg vOwELS
		case 'big vowels' :
		case 'V' :
			for(i = 0; i < len; ++i) {
				c = s[i];
				if(-1 !== VOWELS.indexOf(c)) {
					stylized += c.toUpperCase();
				} else {
					stylized += c.toLowerCase();
				}
			}
			return stylized;

		//	Small i's: DEMENTiA
		case 'small i' : 
		case 'i' : 
			return s.toUpperCase().replace(/I/g, 'i');

		//	mIxeD CaSE (random upper/lower)
		case 'mixed' :
		case 'M' :
			for(i = 0; i < len; i++) {
				if(Math.random() < 0.5) {
					stylized += s[i].toUpperCase();
				} else {
					stylized += s[i].toLowerCase();
				}
			}
			return stylized;

		//	l337 5p34k
		case 'l33t' :
		case '3' :
			for(i = 0; i < len; ++i) {
				c = SIMPLE_ELITE_MAP[s[i].toLowerCase()];
				stylized += c || s[i];				
			}
			return stylized;
	}

	return s;
}

//	Based on http://www.webtoolkit.info/
//	:TODO: Look into lodash padLeft, padRight, etc.
function pad(s, len, padChar, dir, stringSGR, padSGR, useRenderLen) {
	len				= miscUtil.valueWithDefault(len, 0);
	padChar			= miscUtil.valueWithDefault(padChar, ' ');
	dir				= miscUtil.valueWithDefault(dir, 'right');
	stringSGR		= miscUtil.valueWithDefault(stringSGR, '');
	padSGR			= miscUtil.valueWithDefault(padSGR, '');
	useRenderLen 	= miscUtil.valueWithDefault(useRenderLen, true);

	const renderLen	= useRenderLen ? renderStringLength(s) : s.length;
	const padlen	= len >= renderLen ? len - renderLen : 0; 

	switch(dir) {
		case 'L' :
		case 'left' : 
			s = padSGR + new Array(padlen).join(padChar) + stringSGR + s;
			break;

		case 'C' :
		case 'center' :
		case 'both' :
			{
				const right	= Math.ceil(padlen / 2);
				const left	= padlen - right;
				s			= padSGR + new Array(left + 1).join(padChar) + stringSGR + s + padSGR + new Array(right + 1).join(padChar);
			}	
			break;

		case 'R' : 
		case 'right' :
			s = stringSGR + s + padSGR + new Array(padlen).join(padChar);
			break;

		default : break;
	}

	return stringSGR + s;
}

function insert(s, index, substr) {
	return `${s.slice(0, index)}${substr}${s.slice(index)}`;
}

function replaceAt(s, n, t) {
	return s.substring(0, n) + t + s.substring(n + 1);
}

const RE_NON_PRINTABLE = 
	/[\0-\x1F\x7F-\x9F\xAD\u0378\u0379\u037F-\u0383\u038B\u038D\u03A2\u0528-\u0530\u0557\u0558\u0560\u0588\u058B-\u058E\u0590\u05C8-\u05CF\u05EB-\u05EF\u05F5-\u0605\u061C\u061D\u06DD\u070E\u070F\u074B\u074C\u07B2-\u07BF\u07FB-\u07FF\u082E\u082F\u083F\u085C\u085D\u085F-\u089F\u08A1\u08AD-\u08E3\u08FF\u0978\u0980\u0984\u098D\u098E\u0991\u0992\u09A9\u09B1\u09B3-\u09B5\u09BA\u09BB\u09C5\u09C6\u09C9\u09CA\u09CF-\u09D6\u09D8-\u09DB\u09DE\u09E4\u09E5\u09FC-\u0A00\u0A04\u0A0B-\u0A0E\u0A11\u0A12\u0A29\u0A31\u0A34\u0A37\u0A3A\u0A3B\u0A3D\u0A43-\u0A46\u0A49\u0A4A\u0A4E-\u0A50\u0A52-\u0A58\u0A5D\u0A5F-\u0A65\u0A76-\u0A80\u0A84\u0A8E\u0A92\u0AA9\u0AB1\u0AB4\u0ABA\u0ABB\u0AC6\u0ACA\u0ACE\u0ACF\u0AD1-\u0ADF\u0AE4\u0AE5\u0AF2-\u0B00\u0B04\u0B0D\u0B0E\u0B11\u0B12\u0B29\u0B31\u0B34\u0B3A\u0B3B\u0B45\u0B46\u0B49\u0B4A\u0B4E-\u0B55\u0B58-\u0B5B\u0B5E\u0B64\u0B65\u0B78-\u0B81\u0B84\u0B8B-\u0B8D\u0B91\u0B96-\u0B98\u0B9B\u0B9D\u0BA0-\u0BA2\u0BA5-\u0BA7\u0BAB-\u0BAD\u0BBA-\u0BBD\u0BC3-\u0BC5\u0BC9\u0BCE\u0BCF\u0BD1-\u0BD6\u0BD8-\u0BE5\u0BFB-\u0C00\u0C04\u0C0D\u0C11\u0C29\u0C34\u0C3A-\u0C3C\u0C45\u0C49\u0C4E-\u0C54\u0C57\u0C5A-\u0C5F\u0C64\u0C65\u0C70-\u0C77\u0C80\u0C81\u0C84\u0C8D\u0C91\u0CA9\u0CB4\u0CBA\u0CBB\u0CC5\u0CC9\u0CCE-\u0CD4\u0CD7-\u0CDD\u0CDF\u0CE4\u0CE5\u0CF0\u0CF3-\u0D01\u0D04\u0D0D\u0D11\u0D3B\u0D3C\u0D45\u0D49\u0D4F-\u0D56\u0D58-\u0D5F\u0D64\u0D65\u0D76-\u0D78\u0D80\u0D81\u0D84\u0D97-\u0D99\u0DB2\u0DBC\u0DBE\u0DBF\u0DC7-\u0DC9\u0DCB-\u0DCE\u0DD5\u0DD7\u0DE0-\u0DF1\u0DF5-\u0E00\u0E3B-\u0E3E\u0E5C-\u0E80\u0E83\u0E85\u0E86\u0E89\u0E8B\u0E8C\u0E8E-\u0E93\u0E98\u0EA0\u0EA4\u0EA6\u0EA8\u0EA9\u0EAC\u0EBA\u0EBE\u0EBF\u0EC5\u0EC7\u0ECE\u0ECF\u0EDA\u0EDB\u0EE0-\u0EFF\u0F48\u0F6D-\u0F70\u0F98\u0FBD\u0FCD\u0FDB-\u0FFF\u10C6\u10C8-\u10CC\u10CE\u10CF\u1249\u124E\u124F\u1257\u1259\u125E\u125F\u1289\u128E\u128F\u12B1\u12B6\u12B7\u12BF\u12C1\u12C6\u12C7\u12D7\u1311\u1316\u1317\u135B\u135C\u137D-\u137F\u139A-\u139F\u13F5-\u13FF\u169D-\u169F\u16F1-\u16FF\u170D\u1715-\u171F\u1737-\u173F\u1754-\u175F\u176D\u1771\u1774-\u177F\u17DE\u17DF\u17EA-\u17EF\u17FA-\u17FF\u180F\u181A-\u181F\u1878-\u187F\u18AB-\u18AF\u18F6-\u18FF\u191D-\u191F\u192C-\u192F\u193C-\u193F\u1941-\u1943\u196E\u196F\u1975-\u197F\u19AC-\u19AF\u19CA-\u19CF\u19DB-\u19DD\u1A1C\u1A1D\u1A5F\u1A7D\u1A7E\u1A8A-\u1A8F\u1A9A-\u1A9F\u1AAE-\u1AFF\u1B4C-\u1B4F\u1B7D-\u1B7F\u1BF4-\u1BFB\u1C38-\u1C3A\u1C4A-\u1C4C\u1C80-\u1CBF\u1CC8-\u1CCF\u1CF7-\u1CFF\u1DE7-\u1DFB\u1F16\u1F17\u1F1E\u1F1F\u1F46\u1F47\u1F4E\u1F4F\u1F58\u1F5A\u1F5C\u1F5E\u1F7E\u1F7F\u1FB5\u1FC5\u1FD4\u1FD5\u1FDC\u1FF0\u1FF1\u1FF5\u1FFF\u200B-\u200F\u202A-\u202E\u2060-\u206F\u2072\u2073\u208F\u209D-\u209F\u20BB-\u20CF\u20F1-\u20FF\u218A-\u218F\u23F4-\u23FF\u2427-\u243F\u244B-\u245F\u2700\u2B4D-\u2B4F\u2B5A-\u2BFF\u2C2F\u2C5F\u2CF4-\u2CF8\u2D26\u2D28-\u2D2C\u2D2E\u2D2F\u2D68-\u2D6E\u2D71-\u2D7E\u2D97-\u2D9F\u2DA7\u2DAF\u2DB7\u2DBF\u2DC7\u2DCF\u2DD7\u2DDF\u2E3C-\u2E7F\u2E9A\u2EF4-\u2EFF\u2FD6-\u2FEF\u2FFC-\u2FFF\u3040\u3097\u3098\u3100-\u3104\u312E-\u3130\u318F\u31BB-\u31BF\u31E4-\u31EF\u321F\u32FF\u4DB6-\u4DBF\u9FCD-\u9FFF\uA48D-\uA48F\uA4C7-\uA4CF\uA62C-\uA63F\uA698-\uA69E\uA6F8-\uA6FF\uA78F\uA794-\uA79F\uA7AB-\uA7F7\uA82C-\uA82F\uA83A-\uA83F\uA878-\uA87F\uA8C5-\uA8CD\uA8DA-\uA8DF\uA8FC-\uA8FF\uA954-\uA95E\uA97D-\uA97F\uA9CE\uA9DA-\uA9DD\uA9E0-\uA9FF\uAA37-\uAA3F\uAA4E\uAA4F\uAA5A\uAA5B\uAA7C-\uAA7F\uAAC3-\uAADA\uAAF7-\uAB00\uAB07\uAB08\uAB0F\uAB10\uAB17-\uAB1F\uAB27\uAB2F-\uABBF\uABEE\uABEF\uABFA-\uABFF\uD7A4-\uD7AF\uD7C7-\uD7CA\uD7FC-\uF8FF\uFA6E\uFA6F\uFADA-\uFAFF\uFB07-\uFB12\uFB18-\uFB1C\uFB37\uFB3D\uFB3F\uFB42\uFB45\uFBC2-\uFBD2\uFD40-\uFD4F\uFD90\uFD91\uFDC8-\uFDEF\uFDFE\uFDFF\uFE1A-\uFE1F\uFE27-\uFE2F\uFE53\uFE67\uFE6C-\uFE6F\uFE75\uFEFD-\uFF00\uFFBF-\uFFC1\uFFC8\uFFC9\uFFD0\uFFD1\uFFD8\uFFD9\uFFDD-\uFFDF\uFFE7\uFFEF-\uFFFB\uFFFE\uFFFF]/;	//	eslint-disable-line no-control-regex

function isPrintable(s) {
	//
	//	See the following:
	//		https://mathiasbynens.be/notes/javascript-unicode
	//		http://stackoverflow.com/questions/11598786/how-to-replace-non-printable-unicode-characters-javascript
	//		http://stackoverflow.com/questions/12052825/regular-expression-for-all-printable-characters-in-javascript
	//
	//	:TODO: Probably need somthing better here.
	return !RE_NON_PRINTABLE.test(s);
}

function stringLength(s) {
	//	:TODO: See https://mathiasbynens.be/notes/javascript-unicode
	return s.length;
}

function stripAllLineFeeds(s) {
	return s.replace(/\r?\n|[\r\u2028\u2029]/g, '');
}

function debugEscapedString(s) {
	return JSON.stringify(s).slice(1, -1);
}

function stringFromNullTermBuffer(buf, encoding) {
	let nullPos = buf.indexOf(new Buffer( [ 0x00 ] ));
	if(-1 === nullPos) {
		nullPos = buf.length;
	}

	return iconv.decode(buf.slice(0, nullPos), encoding || 'utf-8');
}

function stringToNullTermBuffer(s, options = { encoding : 'utf8', maxBufLen : -1 } ) {
	let buf = iconv.encode( `${s}\0`, options.encoding ).slice(0, options.maxBufLen);
	buf[buf.length - 1] = '\0';	//	make abs sure we null term even if truncated
	return buf;
}

const PIPE_REGEXP			= /(\|[A-Z\d]{2})/g;
//const ANSI_REGEXP			= /[\u001b\u009b][[()#;?]*([0-9]{1,4}(?:;[0-9]{0,4})*)?([0-9A-ORZcf-npqrsuy=><])/g;
//const ANSI_OR_PIPE_REGEXP	= new RegExp(PIPE_REGEXP.source + '|' + ANSI_REGEXP.source, 'g');
const ANSI_OR_PIPE_REGEXP	= new RegExp(PIPE_REGEXP.source + '|' + ANSI.getFullMatchRegExp().source, 'g');

//
//	Similar to substr() but works with ANSI/Pipe code strings
//
function renderSubstr(str, start, length) {
	//	shortcut for empty strings
	if(0 === str.length) {
		return str;
	}

	start	= start || 0;
	length	= length || str.length - start;

	const re = ANSI_OR_PIPE_REGEXP;
	re.lastIndex	 = 0;	//	we recycle the obj; must reset!

	let pos = 0;
	let match;
	let out = '';
	let renderLen = 0;
	let s;
	do {
		pos		= re.lastIndex;
		match	= re.exec(str);

		if(match) {
			if(match.index > pos) {				
				s = str.slice(pos + start, Math.min(match.index, pos + (length - renderLen)));
				start		= 0;	//	start offset applies only once
				out			+= s;
				renderLen	+= s.length;
			}

			out += match[0];
		}
	} while(renderLen < length && 0 !== re.lastIndex);

	//	remainder
	if(pos + start < str.length && renderLen < length) {
		out += str.slice(pos + start, (pos + start + (length - renderLen))); 
		//out += str.slice(pos + start, Math.max(1, pos + (length - renderLen - 1)));
	}

	return out;
}

//
//	Method to return the "rendered" length taking into account Pipe and ANSI color codes. 
//
//	We additionally account for ANSI *forward* movement ESC sequences
//	in the form of ESC[<N>C where <N> is the "go forward" character count.
//
//	See also https://github.com/chalk/ansi-regex/blob/master/index.js
//
function renderStringLength(s) {
	let m;
	let pos;
	let len = 0;

	const re = ANSI_OR_PIPE_REGEXP;
	re.lastIndex = 0;	//	we recycle the rege; reset
	
	//
	//	Loop counting only literal (non-control) sequences
	//	paying special attention to ESC[<N>C which means forward <N>
	//	
	do {
		pos	= re.lastIndex;
		m	= re.exec(s);
		
		if(m) {
			if(m.index > pos) {
				len += s.slice(pos, m.index).length;
			}
			
			if('C' === m[3]) {	//	ESC[<N>C is foward/right
				len += parseInt(m[2], 10) || 0;
			}
		}  
	} while(0 !== re.lastIndex);
	
	if(pos < s.length) {
		len += s.slice(pos).length;
	}
	
	return len;
}

const SIZE_ABBRS = [ 'B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB' ];	//	:) 

function formatByteSizeAbbr(byteSize) {
	if(0 === byteSize) {
		return SIZE_ABBRS[0];	//	B
	}
	
	return SIZE_ABBRS[Math.floor(Math.log(byteSize) / Math.log(1024))];
}

function formatByteSize(byteSize, withAbbr, decimals) {
	withAbbr = withAbbr || false; 
	decimals = decimals || 3;
	const i		= 0 === byteSize ? byteSize : Math.floor(Math.log(byteSize) / Math.log(1024));
	let result	= parseFloat((byteSize / Math.pow(1024, i)).toFixed(decimals));
	if(withAbbr) {
		result += ` ${SIZE_ABBRS[i]}`; 
	}
	return result;
}


//	:TODO: See notes in word_wrap.js about need to consolidate the various ANSI related RegExp's
//const REGEXP_ANSI_CONTROL_CODES		= /(\x1b\x5b)([\?=;0-9]*?)([0-9A-ORZcf-npsu=><])/g;
const REGEXP_ANSI_CONTROL_CODES		= /(?:\x1b\x5b)([\?=;0-9]*?)([A-ORZcf-npsu=><])/g;	//	eslint-disable-line no-control-regex
const ANSI_OPCODES_ALLOWED_CLEAN	= [
	//'A', 'B',	//	up, down
	//'C', 'D',	//	right, left
	'm',		//	color
];

function cleanControlCodes(input, options) {
	let m;
	let pos;
	let cleaned = '';
	
	options = options || {};
		
	//
	//	Loop through |input| adding only allowed ESC
	//	sequences and literals to |cleaned|
	//	
	do {
		pos	= REGEXP_ANSI_CONTROL_CODES.lastIndex;
		m	= REGEXP_ANSI_CONTROL_CODES.exec(input);
		
		if(m) {
			if(m.index > pos) {
				cleaned += input.slice(pos, m.index);
			}

			if(options.all) {
				continue;
			}

			if(ANSI_OPCODES_ALLOWED_CLEAN.indexOf(m[2].charAt(0)) > -1) {
				cleaned += m[0];
			}
		}
		
	} while(0 !== REGEXP_ANSI_CONTROL_CODES.lastIndex);
	
	//	remainder
	if(pos < input.length) {
		cleaned += input.slice(pos);
	}
	
	return cleaned;
}

function prepAnsi(input, options, cb) {
	if(!input) {
		return cb(null, '');
	}

	options.termWidth			= options.termWidth 	|| 80;
	options.termHeight			= options.termHeight	|| 25;
	options.cols				= options.cols || options.termWidth		|| 80;
	options.rows				= options.rows || options.termHeight	|| 'auto';
	options.startCol			= options.startCol || 1;
	options.exportMode			= options.exportMode || false;

	const canvas = Array.from( { length : 'auto' === options.rows ? 25 : options.rows }, () => Array.from( { length : options.cols}, () => new Object() ) );
	const parser = new ANSIEscapeParser( { termHeight : options.termHeight, termWidth : options.termWidth } );

	const state = {
		row	: 0,
		col	: 0,
	};

	let lastRow = 0;

	function ensureRow(row) {
		if(Array.isArray(canvas[row])) {
			return;
		}
		
		canvas[row] = Array.from( { length : options.cols}, () => new Object() );
	}

	parser.on('position update', (row, col) => {
		state.row	= row - 1;
		state.col	= col - 1;

		lastRow		= Math.max(state.row, lastRow);
	});

	parser.on('literal', literal => {
		//
		//	CR/LF are handled for 'position update'; we don't need the chars themselves
		//
		literal = literal.replace(/\r?\n|[\r\u2028\u2029]/g, '');

		for(let c of literal) {
			if(state.col < options.cols && ('auto' === options.rows || state.row < options.rows)) {
				ensureRow(state.row);

				canvas[state.row][state.col].char = c;

				if(state.sgr) {
					canvas[state.row][state.col].sgr = state.sgr;
					state.sgr = null;
				}
			}

			state.col += 1;
		}
	});

	parser.on('control', (match, opCode) => {
		//
		//	Movement is handled via 'position update', so we really only care about
		//	display opCodes
		//
		switch(opCode) {
			case 'm' 	: 
				state.sgr = (state.sgr || '') + match;
				break;
				
			default		: 
				break;
		}
	});

	function getLastPopulatedColumn(row) {
		let col = row.length;
		while(--col > 0) {
			if(row[col].char || row[col].sgr) {
				break;
			}
		}
		return col;
	}

	parser.on('complete', () => {
		let output = '';
		let lastSgr = '';
		let line;

		canvas.slice(0, lastRow + 1).forEach(row => {
			const lastCol = getLastPopulatedColumn(row) + 1;

			let i;
			line = '';
			for(i = 0; i < lastCol; ++i) {
				const col = row[i];
				if(col.sgr) {
					lastSgr = col.sgr;
				}
				line += `${col.sgr || ''}${col.char || ' '}`;
			}

			output += line;

			if(i < row.length) {
				output += `${ANSI.blackBG()}${row.slice(i).map( () => ' ').join('')}${lastSgr}`;
			}

			//if(options.startCol + options.cols < options.termWidth || options.forceLineTerm) {
			if(options.startCol + i < options.termWidth || options.forceLineTerm) {
				output += '\r\n';
			}
		});

		if(options.exportMode) {
			//
			//	If we're in export mode, we do some additional hackery:
			//	
			//	* Hard wrap ALL lines at <= 79 *characters* (not visible columns)
			//	  if a line must wrap early, we'll place a ESC[A ESC[<N>C where <N>
			//	  represents chars to get back to the position we were previously at
			//
			//	* Replace contig spaces with ESC[<N>C as well to save... space.
			//
			//	:TODO: this would be better to do as part of the processing above, but this will do for now
			const MAX_CHARS	= 79 - 8;	//	79 max, - 8 for max ESC seq's we may prefix a line with
			let exportOutput = '';			
			
			let m;
			let afterSeq;
			let wantMore;
			let renderStart;

			splitTextAtTerms(output).forEach(fullLine => {
				renderStart = 0;

				while(fullLine.length > 0) {
					let splitAt;
					const ANSI_REGEXP = ANSI.getFullMatchRegExp();
					wantMore = true;

					while((m = ANSI_REGEXP.exec(fullLine))) {
						afterSeq = m.index + m[0].length;

						if(afterSeq < MAX_CHARS) {
							//	after current seq
							splitAt = afterSeq;
						} else {
							if(m.index < MAX_CHARS) {
								//	before last found seq
								splitAt = m.index;
								wantMore = false;	//	can't eat up any more
							}
							
							break;	//	seq's beyond this point are >= MAX_CHARS
						}
					}

					if(splitAt) {
						if(wantMore) {
							splitAt = Math.min(fullLine.length, MAX_CHARS - 1);
						}
					} else {
						splitAt = Math.min(fullLine.length, MAX_CHARS - 1);
					}

					const part = fullLine.slice(0, splitAt);
					fullLine = fullLine.slice(splitAt);
					renderStart += renderStringLength(part);
					exportOutput += `${part}\r\n`;

					if(fullLine.length > 0) {	//	more to go for this line?
						exportOutput += `${ANSI.up()}${ANSI.right(renderStart)}`;	
					} else {
						exportOutput += ANSI.up();
					}
				}
			});

			return cb(null, exportOutput);
		}

		return cb(null, output);
	});

	parser.parse(input);
}

function isAnsiLine(line) {
	return isAnsi(line);// || renderStringLength(line) < line.length;
}

//
//	Returns true if the line is considered "formatted". A line is
//	considered formatted if it contains:
//	* ANSI
//	* Pipe codes
//	* Extended (CP437) ASCII - https://www.ascii-codes.com/
//	* Tabs
//	* Contigous 3+ spaces before the end of the line
//
function isFormattedLine(line) {
	if(renderStringLength(line) < line.length) {
		return true;	//	ANSI or Pipe Codes
	}

	if(line.match(/[\t\x00-\x1f\x80-\xff]/)) {	//	eslint-disable-line no-control-regex
		return true;
	}

	if(_.trimEnd(line).match(/[ ]{3,}/)) {
		return true;
	}

	return false;
}

function isAnsi(input) {
	//
	//	* ANSI found - limited, just colors
	//	* Full ANSI art
	//	* 
	//	
	//	FULL ANSI art:
	//	* SAUCE present & reports as ANSI art
	//	* ANSI clear screen within first 2-3 codes
	//	* ANSI movement codes (goto, right, left, etc.)
	//	
	//	* 
	/*
	readSAUCE(input, (err, sauce) => {
		if(!err && ('ANSi' === sauce.fileType || 'ANSiMation' === sauce.fileType)) {
			return cb(null, 'ansi');
		}
	});
	*/

	//	:TODO: if a similar method is kept, use exec() until threshold
	const ANSI_DET_REGEXP = /(?:\x1b\x5b)[\?=;0-9]*?[ABCDEFGHJKLMSTfhlmnprsu]/g;	//	eslint-disable-line no-control-regex
	const m = input.match(ANSI_DET_REGEXP) || []; 
	return m.length >= 4;	//	:TODO: do this reasonably, e.g. a percent or soemthing
}

function splitTextAtTerms(s) {
	return s.split(/\r\n|[\n\v\f\r\x85\u2028\u2029]/g);
}