Bottles of Beer

bottles.js

var playBottleSong = function (numberOfBottles) {
	var hasBottlesTemplate = '{beforeTakenDown} {bottlesBefore} of beer on the wall, ' +
		'{beforeTakenDown} {bottlesBefore} of beer. Take one down and pass it around, ' + 
		'{afterTakenDown} {bottlesAfter} of beer on the wall.<br>';

	var noBottlesTemplate = 'No bottles of beer on the wall, no bottles of beer. ' + 
		'Go to the store and buy some more, 99 bottles of beer on the wall.';

	var bottleInfo = {
		beforeTakenDown: numberOfBottles,
		afterTakenDown: numberOfBottles - 1,
		bottlesBefore: 'bottle' + (numberOfBottles == 1 ? '' : 's'),
		bottlesAfter: 'bottle' + (numberOfBottles == 2 ? '' : 's'
	};

	if (numberOfBottles > 0) {
		var songLine = hasBottlesTemplate;

		for (var key in bottleInfo)
			songLine = songLine.replace(new RegExp('{' + key + '}', 'g'), bottleInfo[key]);
	} else {
		var songLine = noBottlesTemplate;
	}

	return numberOfBottles > 0 ? songLine + playBottleSong(numberOfBottles - 1) : songLine;
};