enigma-bbs/core/string_util.js

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

//	ENiGMA½
const miscUtil					= require('./misc_util.js');
const iconv						= require('iconv-lite');

exports.stylizeString				= stylizeString;
exports.pad							= pad;
exports.replaceAt					= replaceAt;
exports.isPrintable					= isPrintable;
exports.debugEscapedString			= debugEscapedString;
exports.stringFromNullTermBuffer	= stringFromNullTermBuffer;
exports.renderSubstr				= renderSubstr;
exports.renderStringLength			= renderStringLength;
exports.cleanControlCodes			= cleanControlCodes;

//	: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 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]/;

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 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');
}

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');

//
//	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;
}


//	: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;
const ANSI_OPCODES_ALLOWED_CLEAN	= [
	'C', 'm' , 
	'A', 'B', 'D'
];

function cleanControlCodes(input) {
	let m;
	let pos;
	let cleaned = '';
	
	//
	//	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(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 getCleanAnsi(input) {
	//
	//	Process |input| and produce |cleaned|, an array
	//	of lines with "clean" ANSI.
	//
	//	Clean ANSI:
	//	* Contains only color/SGR sequences
	//	* All movement (up/down/left/right) removed but positioning
	//	  left intact via spaces/etc.
	//
	//	Temporary processing will occur in a grid. Each cell
	//	containing a character (defaulting to space) possibly a SGR
	//
	
	let m;
	let pos;
	let grid = [];
	let gridPos = { row : 0, col : 0 };
	
	function updateGrid(data, dataType) {
		//	
		//	Start at to grid[row][col] and populate val[0]...val[N]
		//	creating cells as necessary
		//
		if(!grid[gridPos.row]) {
			grid[gridPos.row] = [];
		}
		
		if('literal' === dataType) {
			data.forEach(c => {
				grid[gridPos.row][gridPos.col] = (grid[gridPos.row][gridPos.col] || '') + c;	//	append to existing SGR
				gridPos.col++; 
			});
		} else if('sgr' === dataType) {
			grid[gridPos.row][gridPos.col] = (grid[gridPos.row][gridPos.col] || '') + data;
		}
	}
	
	function literal(s) {
		let charCode;
		const len = s.length;
		for(let i = 0; i < len; ++i) {
			charCode = s.charCodeAt(i) & 0xff;

		}
	}
	
	do {
		pos	= REGEXP_ANSI_CONTROL_CODES.lastIndex;
		m 	= REGEXP_ANSI_CONTROL_CODES.exec(input);
		
		if(null !== m) {
			if(m.index > pos) {
				updateGrid(input.slice(pos, m.index), 'literal');
			}
		}
	} while(0 !== REGEXP_ANSI_CONTROL_CODES.lastIndex);
}