source: Dev/trunk/src/client/dojox/data/FlickrStore.js @ 532

define(["dojo/_base/lang", "dojo/_base/declare", "dojo/_base/array", "dojo/data/util/simpleFetch", "dojo/io/script", 
                "dojo/_base/connect", "dojo/date/stamp", "dojo/AdapterRegistry"], 
  function(lang, declare, array, simpleFetch, scriptIO, connect, dateStamp, AdapterRegistry) {

var FlickrStore = declare("dojox.data.FlickrStore", null, {
        constructor: function(/*Object*/args){
                // summary:
                //              Initializer for the FlickrStore store.
                // description:
                //              The FlickrStore is a Datastore interface to one of the basic services
                //              of the Flickr service, the public photo feed.  This does not provide
                //              access to all the services of Flickr.
                //              This store cannot do * and ? filtering as the flickr service
                //              provides no interface for wildcards.
                if(args && args.label){
                        this.label = args.label;
                }
                if(args && "urlPreventCache" in args){
                        this.urlPreventCache = args.urlPreventCache?true:false;
                }
        },

        _storeRef: "_S",

        label: "title",

        //Flag to allor control of if cache prevention is enabled or not.
        urlPreventCache: true,

        _assertIsItem: function(/* item */ item){
                // summary:
                //              This function tests whether the item passed in is indeed an item in the store.
                // item:
                //              The item to test for being contained by the store.
                if(!this.isItem(item)){
                        throw new Error("dojox.data.FlickrStore: a function was passed an item argument that was not an item");
                }
        },

        _assertIsAttribute: function(/* attribute-name-string */ attribute){
                // summary:
                //              This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.
                // attribute:
                //              The attribute to test for being contained by the store.
                if(typeof attribute !== "string"){
                        throw new Error("dojox.data.FlickrStore: a function was passed an attribute argument that was not an attribute name string");
                }
        },

        getFeatures: function(){
                // summary:
                //              See dojo/data/api/Read.getFeatures()
                return {
                        'dojo.data.api.Read': true
                };
        },

        getValue: function(item, attribute, defaultValue){
                // summary:
                //              See dojo/data/api/Read.getValue()
                var values = this.getValues(item, attribute);
                if(values && values.length > 0){
                        return values[0];
                }
                return defaultValue;
        },

        getAttributes: function(item){
                // summary:
                //              See dojo/data/api/Read.getAttributes()
                return [
                        "title", "description", "author", "datePublished", "dateTaken",
                        "imageUrl", "imageUrlSmall", "imageUrlMedium", "tags", "link"
                ];
        },

        hasAttribute: function(item, attribute){
                // summary:
                //              See dojo/data/api/Read.hasAttributes()
                var v = this.getValue(item,attribute);
                if(v || v === "" || v === false){
                        return true;
                }
                return false;
        },

        isItemLoaded: function(item){
                // summary:
                //              See dojo/data/api/Read.isItemLoaded()
                return this.isItem(item);
        },

        loadItem: function(keywordArgs){
                // summary:
                //              See dojo/data/api/Read.loadItem()
        },

        getLabel: function(item){
                // summary:
                //              See dojo/data/api/Read.getLabel()
                return this.getValue(item,this.label);
        },
        
        getLabelAttributes: function(item){
                // summary:
                //              See dojo/data/api/Read.getLabelAttributes()
                return [this.label];
        },

        containsValue: function(item, attribute, value){
                // summary:
                //              See dojo/data/api/Read.containsValue()
                var values = this.getValues(item,attribute);
                for(var i = 0; i < values.length; i++){
                        if(values[i] === value){
                                return true;
                        }
                }
                return false;
        },

        getValues: function(item, attribute){
                // summary:
                //              See dojo/data/api/Read.getValue()

                this._assertIsItem(item);
                this._assertIsAttribute(attribute);
                var u = lang.hitch(this, "_unescapeHtml");
                var s = lang.hitch(dateStamp, "fromISOString");
                switch(attribute){
                        case "title":
                                return [ u(item.title) ];
                        case "author":
                                return [ u(item.author) ];
                        case "datePublished":
                                return [ s(item.published) ];
                        case "dateTaken":
                                return [ s(item.date_taken) ];
                        case "imageUrlSmall":
                                return [ item.media.m.replace(/_m\./, "_s.") ];
                        case "imageUrl":
                                return [ item.media.m.replace(/_m\./, ".") ];
                        case "imageUrlMedium":
                                return [ item.media.m ];
                        case "link":
                                return [ item.link ];
                        case "tags":
                                return item.tags.split(" ");
                        case "description":
                                return [ u(item.description) ];
                        default:
                                return [];
                }
        },

        isItem: function(item){
                // summary:
                //              See dojo/data/api/Read.isItem()
                if(item && item[this._storeRef] === this){
                        return true;
                }
                return false;
        },
        
        close: function(request){
                // summary:
                //              See dojo/data/api/Read.close()
        },

        _fetchItems: function(request, fetchHandler, errorHandler){
                // summary:
                //              Fetch flickr items that match to a query
                // request:
                //              A request object
                // fetchHandler:
                //              A function to call for fetched items
                // errorHandler:
                //              A function to call on error

                var rq = request.query = request.query || {};

                //Build up the content to send the request for.
                var content = {
                        format: "json",
                        tagmode:"any"
                };

                array.forEach(
                        [ "tags", "tagmode", "lang", "id", "ids" ],
                        function(i){
                                if(rq[i]){ content[i] = rq[i]; }
                        }
                );

                content.id = rq.id || rq.userid || rq.groupid;

                if(rq.userids){
                        content.ids = rq.userids;
                }

                //Linking this up to Flickr is a PAIN!
                var handle = null;
                var getArgs = {
                        url: dojox.data.FlickrStore.urlRegistry.match(request),
                        preventCache: this.urlPreventCache,
                        content: content
                };
                var myHandler = lang.hitch(this, function(data){
                        if(!!handle){
                                connect.disconnect(handle);
                        }

                        //Process the items...
                        fetchHandler(this._processFlickrData(data), request);
                });
                handle = connect.connect("jsonFlickrFeed", myHandler);
                var deferred = scriptIO.get(getArgs);
                
                //We only set up the errback, because the callback isn't ever really used because we have
                //to link to the jsonFlickrFeed function....
                deferred.addErrback(function(error){
                        connect.disconnect(handle);
                        errorHandler(error, request);
                });
        },

        _processFlickrData: function(data){
                var items = [];
                if(data.items){
                        items = data.items;
                        //Add on the store ref so that isItem can work.
                        for(var i = 0; i < data.items.length; i++){
                                var item = data.items[i];
                                item[this._storeRef] = this;
                        }
                }
                return items;
        },

        _unescapeHtml: function(/*String*/ str){
                // summary:
                //              Utility function to un-escape XML special characters in an
                //              HTML string.
                // str: String.
                //              The string to un-escape
                // returns:
                //              HTML String converted back to the normal text (unescaped)
                //              characters (<,>,&, ", etc,).

                //TODO:
                //              Check to see if theres already compatible escape() in
                //              dojo.string or dojo.html
                return  str.replace(/&amp;/gm, "&").
                                        replace(/&lt;/gm, "<").
                                        replace(/&gt;/gm, ">").
                                        replace(/&quot;/gm, "\"").
                                        replace(/&#39;/gm, "'");
        }
});

lang.extend(FlickrStore, simpleFetch);

var feedsUrl = "http://api.flickr.com/services/feeds/";

var reg = FlickrStore.urlRegistry = new AdapterRegistry(true);

reg.register("group pool",
        function(request){ return !!request.query["groupid"]; },
        feedsUrl+"groups_pool.gne"
);

reg.register("default",
        function(request){ return true; },
        feedsUrl+"photos_public.gne"
);

//We have to define this because of how the Flickr API works.
//This somewhat stinks, but what can you do?
if(!jsonFlickrFeed){
        var jsonFlickrFeed = function(data){};
}

return FlickrStore;
});