enigma-bbs/core/word_wrap.js

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JavaScript
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/* jslint node: true */
'use strict';
var assert = require('assert');
var _ = require('lodash');
exports.wordWrapText = wordWrapText;
function wordWrapText(text, options) {
//
// options.*:
// width : word wrap width
// tabHandling : expand (default=expand)
// tabWidth : tab width if tabHandling is 'expand' (default=4)
// tabChar : character to use for tab expansion
//
assert(_.isObject(options), 'Missing options!');
assert(_.isNumber(options.width), 'Missing options.width!');
options.tabHandling = options.tabHandling || 'expand';
if(!_.isNumber(options.tabWidth)) {
options.tabWidth = 4;
}
options.tabChar = options.tabChar || ' ';
//
// Notes
// * Sublime Text 3 for example considers spaces after a word
// part of said word. For example, "word " would be wraped
// in it's entirity.
//
// * Tabs in Sublime Text 3 are also treated as a word, so, e.g.
// "\t" may resolve to " " and must fit within the space.
//
// * If a word is ultimately too long to fit, break it up until it does.
//
// RegExp below is JavaScript '\s' minus the '\t'
//
var re = new RegExp(
'\t|[ \f\n\r\v\u00a0\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006' +
'\u2007\u2008\u2009\u200a\u2028\u2029\u202f\u205f\u3000]', 'g');
var m;
var wordStart = 0;
var results = { wrapped : [ '' ] };
var i = 0;
var word;
var wordLen;
function expandTab(col) {
var remainWidth = options.tabWidth - (col % options.tabWidth);
return new Array(remainWidth).join(options.tabChar);
}
// :TODO: support wrapping pipe code text (e.g. ignore color codes, expand MCI codes)
function addWord() {
word.match(new RegExp('.{0,' + options.width + '}', 'g')).forEach(function wrd(w) {
//wordLen = self.getStringLength(w);
if(results.wrapped[i].length + w.length > options.width) {
//if(results.wrapped[i].length + wordLen > width) {
if(0 === i) {
results.firstWrapRange = { start : wordStart, end : wordStart + w.length };
//results.firstWrapRange = { start : wordStart, end : wordStart + wordLen };
}
results.wrapped[++i] = w;
} else {
results.wrapped[i] += w;
}
});
}
while((m = re.exec(text)) !== null) {
word = text.substring(wordStart, re.lastIndex - 1);
switch(m[0].charAt(0)) {
case ' ' :
word += m[0];
break;
case '\t' :
//
// Expand tab given position
//
// Nice info here: http://c-for-dummies.com/blog/?p=424
//
if('expand' === options.tabHandling) {
word += expandTab(results.wrapped[i].length + word.length) + options.tabChar;
} else {
word += m[0];
}
break;
}
addWord();
wordStart = re.lastIndex + m[0].length - 1;
}
//
// Remainder
//
word = text.substring(wordStart);
addWord();
return results;
}