/** 
   * JSON Schema link handler
   * Copyright (c) 2007 Kris Zyp SitePen (www.sitepen.com)
   * Licensed under the MIT (MIT-LICENSE.txt) license.
   */
  (function (root, factory) {
      if (typeof define === 'function' && define.amd) {
          // AMD. Register as an anonymous module.
          define([], function () {
              return factory();
          });
      } else if (typeof module === 'object' && module.exports) {
          // Node. Does not work with strict CommonJS, but
          // only CommonJS-like environments that support module.exports,
          // like Node.
          module.exports = factory();
      } else {
          // Browser globals
          root.jsonSchemaLinks = factory();
      }
  }(this, function () {// setup primitive classes to be JSON Schema types
  var exports = {};
  exports.cacheLinks = true;
  exports.getLink = function(relation, instance, schema){
  	// gets the URI of the link for the given relation based on the instance and schema
  	// for example:
  	// getLink(
  	// 		"brother", 
  	// 		{"brother_id":33}, 
  	// 		{links:[{rel:"brother", href:"Brother/{brother_id}"}]}) ->
  	//	"Brother/33"
  	var links = schema.__linkTemplates; 
  	if(!links){
  		links = {};
  		var schemaLinks = schema.links;
  		if(schemaLinks && schemaLinks instanceof Array){
  			schemaLinks.forEach(function(link){
  	/*			// TODO: allow for multiple same-name relations
  				if(links[link.rel]){
  					if(!(links[link.rel] instanceof Array)){
  						links[link.rel] = [links[link.rel]];
  					}
  				}*/
  				links[link.rel] = link.href;
  			});
  		}
  		if(exports.cacheLinks){
  			schema.__linkTemplates = links;
  		}
  	}
  	var linkTemplate = links[relation];
  	return linkTemplate && exports.substitute(linkTemplate, instance);
  };
  
  exports.substitute = function(linkTemplate, instance){
  	return linkTemplate.replace(/\{([^\}]*)\}/g, function(t, property){
  			var value = instance[decodeURIComponent(property)];
  			if(value instanceof Array){
  				// the value is an array, it should produce a URI like /Table/(4,5,8) and store.get() should handle that as an array of values
  				return '(' + value.join(',') + ')';
  			}
  			return value;
  		});
  };
  return exports;
  }));