dojo.provide("dojox.charting.DataChart");
dojo.require("dojox.charting.Chart2D");
dojo.require("dojox.charting.themes.PlotKit.blue");
dojo.experimental("dojox.charting.DataChart"); 

(function(){
	
	// Defaults for axes
	//	to be mixed in with xaxis/yaxis custom properties
	// see dojox.charting.axis2d.Default for details.
	var _yaxis = {
		vertical: true, 
		min: 0, 
		max: 10, 
		majorTickStep: 5, 
		minorTickStep: 1,
		natural:false,
		stroke: "black",
		majorTick: {stroke: "black", length: 8},
		minorTick: {stroke: "gray", length: 2},
		majorLabels:true
	};
		
	var _xaxis = {
		natural: true, 		// true - no fractions
		majorLabels: true, 	//show labels on major ticks
		includeZero: false, // do not change on upating chart
		majorTickStep: 1,
		majorTick: {stroke: "black", length: 8},
		fixUpper:"major",
		stroke: "black",
		htmlLabels: true,                                                                    
		from:1
	};
	
	// default for chart elements
	var chartPlot = {
		markers: true,
		tension:2,
		gap:2
	};
	
	dojo.declare("dojox.charting.DataChart", [dojox.charting.Chart2D], {
		//	summary:
		//		DataChart
		//		Extension to the 2D chart that connects to a data store in
		//		a simple manner. Convenience methods have been added for
		//		connecting store item labels to the chart labels.
		//
		//	description:
		//		This code should be considered very experimental and the APIs subject
		//		to change. This is currently an alpha version and will need some testing
		//		and review.
		//
		//		The main reason for this extension is to create animated charts, generally
		//		available with scroll=true, and a property field that gets continually updated.
		//		The previous property settings are kept in memory and displayed until scrolled
		//		off the chart.
		//
		//		Although great effort was made to maintain the integrity of the current
		//		charting APIs, some things have been added or modified in order to get
		//		the store to connect and also to get the data to scroll/animate.
		//		"displayRange" in particular is used to force the xaxis to a specific
		//		size and keep the chart from stretching or squashing to fit the data.
		//
		//		Currently, plot lines can only be set at initialization. Setting
		//		a new store query will have no effect (although using setStore
		//		may work but its untested).
		//
		//	example:
		//
		//	|	var chart = new dojox.charting.DataChart("myNode", {
		//	|		displayRange:8,
		//	|		store:dataStore,
		//	|		query:{symbol:"*"},
		//	|		fieldName:"price"
		//	|		type: dojox.charting.plot2d.Columns
		//	|	});
		//
		//	properties:
		//
		//	scroll: Boolean
		//		Whether live data updates and changes display, like columns moving
		//		up and down, or whether it scrolls to the left as data is added
		scroll:true,
		//
		//	comparative: Boolean
		//		If false, all items are each their own series.
		//		If true, the items are combined into one series
		//		so that their charted properties can be compared.
		comparative:false,
		//
		//		query: String
		//			Used for fetching items. Will vary depending upon store.
		query: "*",
		//
		//		queryOptions: String
		//			Option used for fetching items
		queryOptions: "",
		//
		/*=====
			//	start:Number
			//		first item to fetch from store
			//	count:Number
			//		Total amount of items to fetch from store
			//	sort:Object
			//		Paramaters to sort the fetched items from store
		=====*/
		//
		//		fieldName: String
		//			The field in the store item that is getting charted
		fieldName: "value",
		//
		//		chartTheme: dojox.charting.themes.*
		//			The theme to style the chart. Defaults to PlotKit.blue.
		chartTheme: dojox.charting.themes.PlotKit.blue,
		//
		//		displayRange: Number
		//			The number of major ticks to show on the xaxis
		displayRange:0,
		//
		// 		stretchToFit: Boolean
		//			If true, chart is sized to data. If false, chart is a
		//			fixed size. Note, is overridden by displayRange.
		//			TODO: Stretch for the y-axis?
		stretchToFit:true,
		//
		//		minWidth: Number
		//			The the smallest the chart width can be
		minWidth:200,
		//
		//		minHeight: Number
		//			The the smallest the chart height can be
		minHeight:100,
		//
		//		showing: Boolean
		//			Whether the chart is showing (default) on
		//			initialization or hidden.
		showing: true,
		//
		//		label: String
		//			The name field of the store item
		//			DO NOT SET: Set from store.labelAttribute
		label: "name",
		
		constructor: function(node, kwArgs){
			// summary:
			//		Set up properties and initialize chart build.
			//
			//	arguments:
			//		node: DomNode
			//			The node to attach the chart to.
			//		kwArgs:	Object
			//			xaxis: Object
			//				optional parameters for xaxis (see above)
			//			yaxis: Object
			//				optional parameters for yaxis (see above)
			//			store: Object
			//				dojo.data store (currently nly supports Persevere)
			//			xaxis: Object
			//				First query for store
			//			grid: Object
			//				Options for the grid plot
			//			chartPlot: Object
			//				Options for chart elements (lines, bars, etc)
			
			this.domNode = dojo.byId(node);

			dojo.mixin(this, kwArgs);
			
			this.xaxis = dojo.mixin(dojo.mixin({}, _xaxis), kwArgs.xaxis);
			if(this.xaxis.labelFunc == "seriesLabels"){
				this.xaxis.labelFunc = dojo.hitch(this, "seriesLabels");
			}
			
			this.yaxis = dojo.mixin(dojo.mixin({}, _yaxis), kwArgs.yaxis);
			if(this.yaxis.labelFunc == "seriesLabels"){
				this.yaxis.labelFunc = dojo.hitch(this, "seriesLabels");
			}
			
			
			this.convertLabels(this.yaxis);
			this.convertLabels(this.xaxis);
			
			this.onSetItems = {};
			this.onSetInterval = 0;
			this.dataLength = 0;
			this.seriesData = {};
			this.seriesDataBk = {};
			this.firstRun =  true;
			
			this.dataOffset = 0;
			
			// FIXME: looks better with this, but it's custom
			this.chartTheme.plotarea.stroke = {color: "gray", width: 3};
			
			this.setTheme(this.chartTheme);
			
			// displayRange overrides stretchToFit
			if(this.displayRange){
				this.stretchToFit = false;
			}
			if(!this.stretchToFit){
				this.xaxis.to = this.displayRange;
			}
			this.addAxis("x", this.xaxis);
			this.addAxis("y", this.yaxis);
			chartPlot.type = kwArgs.type || "Markers"
			this.addPlot("default", dojo.mixin(chartPlot, kwArgs.chartPlot));
			
			this.addPlot("grid", dojo.mixin(kwArgs.grid || {}, {type: "Grid", hMinorLines: true}));
			
			if(this.showing){
				this.render();	
			}
			
			if(kwArgs.store){
				this.setStore(kwArgs.store, kwArgs.query, kwArgs.fieldName, kwArgs.queryOptions);	
			}
		},
		
		setStore: function(/*Object*/store, /* ? String*/query, /* ? String*/fieldName, /* ? Object */queryOptions){
			//	 summary:
			//		Sets the chart store and query
			//		then does the first fetch and
			//		connects to subsequent changes.
			//
			// TODO: Not handling resetting store
			//
			this.firstRun = true;
			this.store = store || this.store;
			this.query = query || this.query;
			this.fieldName = fieldName || this.fieldName;
			this.label = this.store.getLabelAttributes();
			this.queryOptions = queryOptions || queryOptions;
			this.fetch();
			dojo.connect(this.store, "onSet", this, "onSet");
			dojo.connect(this.store, "onError", this, "onError");
		},
		
		show: function(){
			// summary:
			//		If chart is hidden, show it
			if(!this.showing){
				dojo.style(this.domNode, "display", "");	
				this.showing = true;
				this.render();
			}
		},
		hide: function(){
			// 	summary:
			//		If chart is showing, hide it
			//		Prevents rendering while hidden
			if(this.showing){
				dojo.style(this.domNode, "display", "none");
				this.showing = false;
			}
		},
		
		onSet: function(/*storeObject*/item){
			//	summary:
			//		Fired when a store item changes.
			//		Collects the item calls and when
			//		done (after 200ms), sends item
			//		array to onData().
			//
			// FIXME: Using labels instead of IDs for item
			//	identifiers here and in the chart series. This
			//	is obviously short sighted, but currently used
			//	for seriesLabels. Workaround for potential bugs
			//	is to assign a label for which all items are unique.
			var nm = this.getProperty(item, this.label);
			
			// FIXME: why the check for if-in-runs?
			if(nm in this.runs || this.comparative){
				clearTimeout(this.onSetInterval);
				if(!this.onSetItems[nm]){
					this.onSetItems[nm] = item;
				}
				this.onSetInterval = setTimeout(dojo.hitch(this, function(){
					clearTimeout(this.onSetInterval);
					var items = [];
					for(var nm in this.onSetItems){
						items.push(this.onSetItems[nm]);
					}
					this.onData(items);
					this.onSetItems = {};
				}),200);
			}
		},
		
		onError: function(/*Error*/err){
			// stub
			//	Fires on fetch error
			console.error(err);
		},

		onDataReceived: function(/*Array*/items){
			// summary:
			//		stub. Fires after data is received but
			//		before data is parsed and rendered
		},
		
		getProperty: function(/*storeObject*/item, prop){
			// summary:
			//		The main use of this function is to determine
			//		between a single value and an array of values.
			//		Other property types included for convenience.
			//
			if(prop==this.label){
				return this.store.getLabel(item);
			}
			if(prop=="id"){
				return this.store.getIdentity(item);
			}
			var value = this.store.getValues(item, prop);
			if(value.length < 2){
				value = this.store.getValue(item, prop);
			}
			return value;
		},
		onData: function(/*Array*/items){
			//	summary:
			//		Called after a completed fetch
			//		or when store items change.
			//		On first run, sets the chart data,
			//		then updates chart and legends.
			//
			//console.log("Store:", store);console.log("items: (", items.length+")", items);console.log("Chart:", this);
			
			if(!items.length){ return; }
			
			if(this.items && this.items.length != items.length){
				dojo.forEach(items, function(m){
					var id = this.getProperty(m, "id");
					dojo.forEach(this.items, function(m2, i){
						if(this.getProperty(m2, "id") == id){
							this.items[i] = m2;
						}
					},this);
				}, this);
				items = this.items;
			}
			if(this.stretchToFit){
				this.displayRange = items.length;
			}
			this.onDataReceived(items);
			this.items = items;
			
			
			if(this.comparative){
				// all items are gathered together and used as one
				//	series so their properties can be compared.
				var nm = "default";
				
				this.seriesData[nm] = [];
				this.seriesDataBk[nm] = [];
				dojo.forEach(items, function(m, i){
					var field = this.getProperty(m, this.fieldName);
					this.seriesData[nm].push(field);
				}, this);
				
			}else{
				
				// each item is a seperate series.
				dojo.forEach(items, function(m, i){
					var nm = this.store.getLabel(m);
					if(!this.seriesData[nm]){
						this.seriesData[nm] = [];
						this.seriesDataBk[nm] = [];
					}
					
					// the property in the item we are using
					var field = this.getProperty(m, this.fieldName);
					if(dojo.isArray(field)){
						// Data is an array, so it's a snapshot, and not
						//	live, updating data
						//
						this.seriesData[nm] = field;
			
					}else{
						if(!this.scroll){ 
							// Data updates, and "moves in place". Columns and
							//	line markers go up and down
							//
							// create empty chart elements by starting an array
							//	with zeros until we reach our relevant data
							var ar = dojo.map(new Array(i+1), function(){ return 0; });
							ar.push(Number(field));
							this.seriesData[nm] = ar;
						
						}else{
							// Data updates and scrolls to the left
							if(this.seriesDataBk[nm].length > this.seriesData[nm].length){
								this.seriesData[nm] = this.seriesDataBk[nm];
							}
							// Collecting and storing series data. The items come in
							//	only one at a time, but we need to display historical
							//	data, so it is kept in memory.
							this.seriesData[nm].push(Number(field));
						}
						this.seriesDataBk[nm].push(Number(field));
					}
				}, this);
			}
			
			// displayData is the segment of the data array that is within
			// the chart boundaries
			var displayData;
			if(this.firstRun){
				// First time around we need to add the series (chart lines)
				//	to the chart.
				this.firstRun = false;
				for(nm in this.seriesData){
					this.addSeries(nm, this.seriesData[nm]);
					displayData = this.seriesData[nm];
				}
			
			}else{
				
				// update existing series
				for(nm in this.seriesData){
					displayData = this.seriesData[nm];
					
					if(this.scroll && displayData.length > this.displayRange){
						// chart lines have gone beyond the right boundary.
						this.dataOffset = displayData.length-this.displayRange - 1;
						displayData = displayData.slice(displayData.length-this.displayRange, displayData.length);
					}
					this.updateSeries(nm, displayData);
				}
			}
			this.dataLength = displayData.length;
			
			if(this.showing){
				this.render();	
			}
			
		},
		
		fetch: function(){
			// summary:
			//		Fetches initial data. Subsequent changes
			//		are received via onSet in data store.
			//
			if(!this.store){ return; }
			
			this.store.fetch({query:this.query, queryOptions:this.queryOptions, start:this.start, count:this.count, sort:this.sort, onComplete:dojo.hitch(this, "onData"), onError:dojo.hitch(this, "onError")});
		},
		
		convertLabels: function(axis){
			// summary:
			//		Convenience method to convert a label array of strings
			//		into an array of objects
			//
			if(!axis.labels || dojo.isObject(axis.labels[0])){ return null; }
			
			axis.labels = dojo.map(axis.labels, function(ele, i){
				return {value:i, text:ele}; 
			});
			return null; // null
		},
		
		seriesLabels: function(/*Number*/val){
			// summary:
			//		Convenience method that sets series labels based on item labels.
			val--;
			if(this.series.length<1 || (!this.comparative && val>this.series.length)){ return "-"; }
			if(this.comparative){
				return this.store.getLabel(this.items[val]);// String
				
			}else{
				// FIXME:
				// Here we are setting the label base on if there is data in the array slot.
				//	A typical series may look like: [0,0,3.1,0,0,0] which mean the data is populated in the
				//	3rd row or column. This works well and keeps the labels aligned but has a side effect
				//	of not showing the label is the data is zero. Work around is to not go lower than
				//	0.01 or something.
				for(var i=0;i<this.series.length; i++){
					if(this.series[i].data[val]>0){
						return this.series[i].name; // String
					}
				}
			}
			return "-"; // String
			
		},
		
		resizeChart: function(/*Object*/dim){
			//	summary:
			//		Call this function to change the chart size.
			//		Can be connected to a layout widget that calls
			//		resize.
			//
			var w = Math.max(dim.w, this.minWidth);
			var h = Math.max(dim.h, this.minHeight);
			this.resize(w, h);
		}
	});
	
})();