URL Pattern Parser

URLPatternParser

// We need to write a function in JavaScript that parses all the variable parts of a 
// url, and any url parameters, into a hash. The function should take two arguments:
// 1. A "url format" string, which describes the format of a url that can contain 
// constant parts and variable parts (where "parts" of a url are separated with "/").
// All variable parts begin with a colon. Here is an example "url format" string:
// "/v6/:collecton/:id"
// 2. The second argument is a particular url that is guaranteed to have the format 
// specified by the first argument. It may also contain url parameters. For instance, 
// given the example url format string above, the second argument might be:
// "/v6/photos/3?size=large&res=high
// Given these two arguments, our parsing function should return a hash that maps 
// the variable parts of the url and any supplied url parameters to their values:
// {
// collection: "photos",
// id: "3",
// size: "large",
// res: "high"
// }
// Please write the parsing function.

function urlParse(urlFormat, url) {

	var result = {},
			urlMask = [],
			maskIndex = 0,
			urlFormatSplit,
			queryString,
			param, value, i;

	// seperate things as necessary 

	urlFormatSplit = urlFormat.split("/");
	queryString = url.split("?")[1];
	urlPart 		= url.split("?")[0];
	urlSplit 		= urlPart.split("/");

	// determine which indices represent variables

	for (i = 0; i < urlFormatSplit.length; i++) {
		debugger;
		if (urlFormatSplit[i].indexOf(':') === 0) {
			var name = urlFormatSplit[i].substr(1, this.length);
			urlMask.push({ "index" : i, "name" : name });
		} 
	}

	// [{ "index" : 1, "name" : "collection" }, 
	//  { "index" : 2, "name" : "id" }]
	
	for (i = 0; i < urlSplit.length; i++) {
		if (urlMask[maskIndex].index === i) {
			var key = urlMask[maskIndex].name;
			result[key] = urlSplit[i];
			maskIndex += 1;
		}
	}

	// pull out qs values and add to result
	
	queryStringSplit = queryString.split("&");

	for (i = 0; i < queryStringSplit.length; i++) {
		var thisParamAndResult = queryStringSplit[i].split("=");
		var key = thisParamAndResult[0];
		result[key] = thisParamAndResult[1];
	}

	return result;

}

(function() {
	var urlFormat = "/v6/:collecton/:id";
	var url = "/v6/photos/3?size=large&res=high";
	var result = urlParse(urlFormat, url);
	console.log("result:");
	console.log(result);
})();