Few functions to help search for a matches of a substring in an array

pattern_in_array_finder.js

var arr = [
    '1 Chronicles', '1 Corinthians',   '1 John',          '1 Kings',
    '1 Peter',      '1 Samuel',        '1 Thessalonians', '1 Timothy',
    '2 Chronicles', '2 Corinthians',   '2 John',          '2 Kings',
    '2 Peter',      '2 Samuel',        '2 Thessalonians', '2 Timothy',
    '3 John',       'Acts',            'Amos',            'Colossians',   
    'Daniel',
    'Deuteronomy',  'Ecclesiastes',    'Ephesians',       'Esther',
    'Exodus',       'Ezekiel',         'Ezra',            'Galatians', 
    'Genesis',      'Habakkuk',        'Haggai',          'Hebrews',
    'Hosea',        'Isaiah',          'James',           'Jeremiah',
    'Job',          'Joel',            'John',            'Jonah',
    'Joshua',       'Jude',            'Judges',          'Lamentations',
    'Leviticus',    'Luke',            'Malachi',         'Mark',
    'Matthew',      'Micah',           'Nahum',           'Nehemiah',
    'Numbers',      'Obadiah',         'Philemon',        'Philippians',
    'Proverbs',     'Psalm',           'Revelation',      'Romans',
    'Ruth',         'Song of Solomon', 'Titus',           'Zechariah',    
    'Zephaniah' ];

var search = "Eze";

function preprocess (arr) {
	if (typeof arr == "string") {
		return arr.replace (/\s+/g, "+").toLowerCase()
	}
	for (var i in arr) {
		arr[i] = preprocess(arr[i]);
	}
}

function postprocess (arr) {
	if (typeof arr == "string") {
		return arr
			.replace (/(\+\w)/g, function ($1) { 
				return " " + $1.charAt(1).toUpperCase(); 
			})
			.replace (/[a-zA-Z]/, function ($2) { 
				return $2.toUpperCase(); 
			});
	}
	for (var i in arr) {
		arr[i] = postprocess(arr[i]);
	}
}

function make_radix_tree (arr, prefix="") {
	if (!Array.isArray(arr)) {
		return arr;
	}

	var trix = {};
	for (var i in arr) {

		var str = arr[i];
		var key = str.charAt(0);

		if (str.length > 1) {
			var str = str.substr(1);

			if (!Array.isArray(trix[key]))
				trix[key] = [];

			trix[key].push(str);
		} else {
			trix[key] = prefix + str;
		}
		
	}

	for (var j in trix) {
		trix[j] = make_radix_tree(trix[j], prefix + j);
	}

	return trix;
}

function compress_radix_tree (trix) {
	if (typeof trix == "string") {
		return [trix];
	}

	var compressed = [];
	for (var key in trix) {
		compressed = compressed.concat(compress_radix_tree(trix[key]));
	}

	return compressed
}

function findPrefix (prefix, arr) {
	preprocess(arr);
	prefix = preprocess(prefix);

	var trix = make_radix_tree(arr);
	var subtrix;
	for (var i = 0; i < prefix.length; i++) {
		subtrix = trix[prefix[i]]
		if (subtrix == null) {
			// no such prefix 
			// return best matches 
			return compress_radix_tree(trix)
		} 
		trix = subtrix;
	}

	var result;
	if (typeof trix == "object") {
		result = compress_radix_tree(trix);
	} else result = trix;
	postprocess (result);
	return result;
}

console.log(findPrefix(search, arr));