function ResourceManager(options) {
	var t = this;
		
	// exports
  t.fetchResources = fetchResources;
		
	// locals
	var resources = [];
	var cache = [];
	
	_addResourceSources(options.resources);
	
	/**
     * ----------------------------------------------------------------
     * Categorize and add the provided sources
     * ----------------------------------------------------------------
     */
  function _addResourceSources(sources) {
    var resource = {};
    
    if ($.isFunction(sources)) {
      // is it a function?
      resource = {
        resources: sources
      };
      resources.push(resource);
    } else if (typeof sources == 'string') {
      // is it a URL string?
      resource = {
          url: sources
      };
      resources.push(resource);
    } else if (typeof sources == 'object') {
      // is it json object?
      for (var i=0; i<sources.length; i++) {
          var s = sources[i];
          normalizeSource(s);
          resource = {
              resources: s
          };
          resources.push(resource);
      }
    }
  }

	/**
	 * ----------------------------------------------------------------
	 * Fetch resources from source array
	 * ----------------------------------------------------------------
	 */
	function fetchResources(useCache, currentView) {
    // if useCache is not defined, default to true
    useCache = useCache || true;
    
    if (useCache) {
      // get from cache
      return cache;
    } else {
      // do a fetch resource from source, rebuild cache
      cache = [];
      var len = resources.length;
      for (var i = 0; i < len; i++) {
          var resources = _fetchResourceSource(resources[i], currentView);
          cache = cache.concat(resources);
      }
      return cache;
    }
	}

	/**
     * ----------------------------------------------------------------
     * Fetch resources from each source.  If source is a function, call
     * the function and return the resource.  If source is a URL, get
     * the data via synchronized ajax call.  If the source is an
     * object, return it as is.
     * ----------------------------------------------------------------
     */
  function _fetchResourceSource(source, currentView) {
    var resources = source.resources;
   
    if (resources) {
      if ($.isFunction(resources)) {
          return resources();
      }
    } else {
      var url = source.url;
      if (url) {
        var data={};
        if (typeof currentView === 'object') {
          var startParam = options.startParam;
          var endParam = options.endParam;
          if (startParam) {
              data[startParam] = Math.round(+currentView.visStart / 1000);
          }
          if (endParam) {
              data[endParam] = Math.round(+currentView.visEnd / 1000);
          }
        }

        $.ajax($.extend({}, source, {
          data: data,
          dataType: 'json',
          cache: false,
          success: function(res) {
              res = res || [];
              resources = res;
          },
          error: function() {
              alert("ajax error getting json from "+url);
          },
          async: false  // too much work coordinating callbacks so dumb it down
        }));
      }
    }
    return resources;
  }

/**
 * ----------------------------------------------------------------
 * normalize the source object
 * ----------------------------------------------------------------
 */
	function normalizeSource(source) {
    if (source.className) {
      if (typeof source.className == 'string') {
        source.className = source.className.split(/\s+/);
      }
    } else {
      source.className = [];
    }
    var normalizers = fc.sourceNormalizers;
    for (var i=0; i<normalizers.length; i++) {
      normalizers[i](source);
    }
	}
}