/* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
 * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
 * full text of the license. */
 
/**
 * @requires OpenLayers/Layer.js
 * @requires OpenLayers/Renderer.js
 * @requires OpenLayers/StyleMap.js
 * @requires OpenLayers/Feature/Vector.js
 * @requires OpenLayers/Console.js
 */
 
/**
 * Class: OpenLayers.Layer.Vector
 * Instances of OpenLayers.Layer.Vector are used to render vector data from
 *     a variety of sources. Create a new vector layer with the
 *     <OpenLayers.Layer.Vector> constructor.
 *
 * Inherits from:
 *  - <OpenLayers.Layer>
 */
OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
 
    /**
     * Constant: EVENT_TYPES
     * {Array(String)} Supported application event types.  Register a listener
     *     for a particular event with the following syntax:
     * (code)
     * layer.events.register(type, obj, listener);
     * (end)
     *
     * Listeners will be called with a reference to an event object.  The
     *     properties of this event depends on exactly what happened.
     *
     * All event objects have at least the following properties:
     * object - {Object} A reference to layer.events.object.
     * element - {DOMElement} A reference to layer.events.element.
     *
     * Supported map event types (in addition to those from <OpenLayers.Layer>):
     * beforefeatureadded - Triggered before a feature is added.  Listeners
     *      will receive an object with a *feature* property referencing the
     *      feature to be added.  To stop the feature from being added, a
     *      listener should return false.
     * beforefeaturesadded - Triggered before an array of features is added.
     *      Listeners will receive an object with a *features* property
     *      referencing the feature to be added. To stop the features from
     *      being added, a listener should return false.
     * featureadded - Triggered after a feature is added.  The event
     *      object passed to listeners will have a *feature* property with a
     *      reference to the added feature.
     * featuresadded - Triggered after features are added.  The event
     *      object passed to listeners will have a *features* property with a
     *      reference to an array of added features.
     * beforefeatureremoved - Triggered before a feature is removed. Listeners
     *      will receive an object with a *feature* property referencing the
     *      feature to be removed.
     * featureremoved - Triggerd after a feature is removed. The event
     *      object passed to listeners will have a *feature* property with a
     *      reference to the removed feature.
     * featuresremoved - Triggered after features are removed. The event
     *      object passed to listeners will have a *features* property with a
     *      reference to an array of removed features.
     * featureselected - Triggered after a feature is selected.  Listeners
     *      will receive an object with a *feature* property referencing the
     *      selected feature.
     * featureunselected - Triggered after a feature is unselected.
     *      Listeners will receive an object with a *feature* property
     *      referencing the unselected feature.
     * beforefeaturemodified - Triggered when a feature is selected to 
     *      be modified.  Listeners will receive an object with a *feature* 
     *      property referencing the selected feature.
     * featuremodified - Triggered when a feature has been modified.
     *      Listeners will receive an object with a *feature* property referencing 
     *      the modified feature.
     * afterfeaturemodified - Triggered when a feature is finished being modified.
     *      Listeners will receive an object with a *feature* property referencing 
     *      the modified feature.
     * vertexmodified - Triggered when a vertex within any feature geometry
     *      has been modified.  Listeners will receive an object with a
     *      *feature* property referencing the modified feature, a *vertex*
     *      property referencing the vertex modified (always a point geometry),
     *      and a *pixel* property referencing the pixel location of the
     *      modification.
     * sketchstarted - Triggered when a feature sketch bound for this layer
     *      is started.  Listeners will receive an object with a *feature*
     *      property referencing the new sketch feature and a *vertex* property
     *      referencing the creation point.
     * sketchmodified - Triggered when a feature sketch bound for this layer
     *      is modified.  Listeners will receive an object with a *vertex*
     *      property referencing the modified vertex and a *feature* property
     *      referencing the sketch feature.
     * sketchcomplete - Triggered when a feature sketch bound for this layer
     *      is complete.  Listeners will receive an object with a *feature*
     *      property referencing the sketch feature.  By returning false, a
     *      listener can stop the sketch feature from being added to the layer.
     * refresh - Triggered when something wants a strategy to ask the protocol
     *      for a new set of features.
     */
    EVENT_TYPES: ["beforefeatureadded", "beforefeaturesadded",
                  "featureadded", "featuresadded",
                  "beforefeatureremoved", "featureremoved", "featuresremoved",
                  "beforefeatureselected", "featureselected", "featureunselected", 
                  "beforefeaturemodified", "featuremodified", "afterfeaturemodified",
                  "vertexmodified", "sketchstarted", "sketchmodified",
                  "sketchcomplete", "refresh"],
 
    /**
     * APIProperty: isBaseLayer
     * {Boolean} The layer is a base layer.  Default is true.  Set this property
     * in the layer options
     */
    isBaseLayer: false,
 
    /** 
     * APIProperty: isFixed
     * {Boolean} Whether the layer remains in one place while dragging the
     * map.
     */
    isFixed: false,
 
    /** 
     * APIProperty: isVector
     * {Boolean} Whether the layer is a vector layer.
     */
    isVector: true,
    
    /** 
     * APIProperty: features
     * {Array(<OpenLayers.Feature.Vector>)} 
     */
    features: null,
    
    /** 
     * Property: selectedFeatures
     * {Array(<OpenLayers.Feature.Vector>)} 
     */
    selectedFeatures: null,
    
    /**
     * Property: unrenderedFeatures
     * {Object} hash of features, keyed by feature.id, that the renderer
     *     failed to draw
     */
    unrenderedFeatures: null,
 
    /**
     * APIProperty: reportError
     * {Boolean} report friendly error message when loading of renderer
     * fails.
     */
    reportError: true, 
 
    /** 
     * APIProperty: style
     * {Object} Default style for the layer
     */
    style: null,
    
    /**
     * Property: styleMap
     * {<OpenLayers.StyleMap>}
     */
    styleMap: null,
    
    /**
     * Property: strategies
     * {Array(<OpenLayers.Strategy>})} Optional list of strategies for the layer.
     */
    strategies: null,
    
    /**
     * Property: protocol
     * {<OpenLayers.Protocol>} Optional protocol for the layer.
     */
    protocol: null,
    
    /**
     * Property: renderers
     * {Array(String)} List of supported Renderer classes. Add to this list to
     * add support for additional renderers. This list is ordered:
     * the first renderer which returns true for the  'supported()'
     * method will be used, if not defined in the 'renderer' option.
     */
    renderers: ['SVG', 'VML', 'Canvas'],
    
    /** 
     * Property: renderer
     * {<OpenLayers.Renderer>}
     */
    renderer: null,
    
    /**
     * APIProperty: rendererOptions
     * {Object} Options for the renderer. See {<OpenLayers.Renderer>} for
     *     supported options.
     */
    rendererOptions: null,
    
    /** 
     * APIProperty: geometryType
     * {String} geometryType allows you to limit the types of geometries this
     * layer supports. This should be set to something like
     * "OpenLayers.Geometry.Point" to limit types.
     */
    geometryType: null,
 
    /** 
     * Property: drawn
     * {Boolean} Whether the Vector Layer features have been drawn yet.
     */
    drawn: false,
 
    /**
     * Constructor: OpenLayers.Layer.Vector
     * Create a new vector layer
     *
     * Parameters:
     * name - {String} A name for the layer
     * options - {Object} Optional object with non-default properties to set on
     *           the layer.
     *
     * Returns:
     * {<OpenLayers.Layer.Vector>} A new vector layer
     */
    initialize: function(name, options) {
        
        // concatenate events specific to vector with those from the base
        this.EVENT_TYPES =
            OpenLayers.Layer.Vector.prototype.EVENT_TYPES.concat(
            OpenLayers.Layer.prototype.EVENT_TYPES
        );
 
        OpenLayers.Layer.prototype.initialize.apply(this, arguments);
 
        // allow user-set renderer, otherwise assign one
        if (!this.renderer || !this.renderer.supported()) {  
            this.assignRenderer();
        }
 
        // if no valid renderer found, display error
        if (!this.renderer || !this.renderer.supported()) {
            this.renderer = null;
            this.displayError();
        } 
 
        if (!this.styleMap) {
            this.styleMap = new OpenLayers.StyleMap();
        }
 
        this.features = [];
        this.selectedFeatures = [];
        this.unrenderedFeatures = {};
        
        // Allow for custom layer behavior
        if(this.strategies){
            for(var i=0, len=this.strategies.length; i<len; i++) {
                this.strategies[i].setLayer(this);
            }
        }
 
    },
 
    /**
     * APIMethod: destroy
     * Destroy this layer
     */
    destroy: function() {
        if (this.strategies) {
            var strategy, i, len;
            for(i=0, len=this.strategies.length; i<len; i++) {
                strategy = this.strategies[i];
                if(strategy.autoDestroy) {
                    strategy.destroy();
                }
            }
            this.strategies = null;
        }
        if (this.protocol) {
            if(this.protocol.autoDestroy) {
                this.protocol.destroy();
            }
            this.protocol = null;
        }
        this.destroyFeatures();
        this.features = null;
        this.selectedFeatures = null;
        this.unrenderedFeatures = null;
        if (this.renderer) {
            this.renderer.destroy();
        }
        this.renderer = null;
        this.geometryType = null;
        this.drawn = null;
        OpenLayers.Layer.prototype.destroy.apply(this, arguments);  
    },
 
    /**
     * Method: refresh
     * Ask the layer to request features again and redraw them.  Triggers
     *     the refresh event if the layer is in range and visible.
     *
     * Parameters:
     * obj - {Object} Optional object with properties for any listener of
     *     the refresh event.
     */
    refresh: function(obj) {
        if(this.calculateInRange() && this.visibility) {
            this.events.triggerEvent("refresh", obj);
        }
    },
 
    /** 
     * Method: assignRenderer
     * Iterates through the available renderer implementations and selects 
     * and assigns the first one whose "supported()" function returns true.
     */    
    assignRenderer: function()  {
        for (var i=0, len=this.renderers.length; i<len; i++) {
            var rendererClass = OpenLayers.Renderer[this.renderers[i]];
            if (rendererClass && rendererClass.prototype.supported()) {
                this.renderer = new rendererClass(this.div,
                    this.rendererOptions);
                break;
            }  
        }  
    },
 
    /** 
     * Method: displayError 
     * Let the user know their browser isn't supported.
     */
    displayError: function() {
        if (this.reportError) {
            OpenLayers.Console.userError(OpenLayers.i18n("browserNotSupported", 
                                     {'renderers':this.renderers.join("\n")}));
        }    
    },
 
    /** 
     * Method: setMap
     * The layer has been added to the map. 
     * 
     * If there is no renderer set, the layer can't be used. Remove it.
     * Otherwise, give the renderer a reference to the map and set its size.
     * 
     * Parameters:
     * map - {<OpenLayers.Map>} 
     */
    setMap: function(map) {        
        OpenLayers.Layer.prototype.setMap.apply(this, arguments);
 
        if (!this.renderer) {
            this.map.removeLayer(this);
        } else {
            this.renderer.map = this.map;
            this.renderer.setSize(this.map.getSize());
        }
    },
 
    /**
     * Method: afterAdd
     * Called at the end of the map.addLayer sequence.  At this point, the map
     *     will have a base layer.  Any autoActivate strategies will be
     *     activated here.
     */
    afterAdd: function() {
        if(this.strategies) {
            var strategy, i, len;
            for(i=0, len=this.strategies.length; i<len; i++) {
                strategy = this.strategies[i];
                if(strategy.autoActivate) {
                    strategy.activate();
                }
            }
        }
    },
 
    /**
     * Method: removeMap
     * The layer has been removed from the map.
     *
     * Parameters:
     * map - {<OpenLayers.Map>}
     */
    removeMap: function(map) {
        if(this.strategies) {
            var strategy, i, len;
            for(i=0, len=this.strategies.length; i<len; i++) {
                strategy = this.strategies[i];
                if(strategy.autoActivate) {
                    strategy.deactivate();
                }
            }
        }
    },
    
    /**
     * Method: onMapResize
     * Notify the renderer of the change in size. 
     * 
     */
    onMapResize: function() {
        OpenLayers.Layer.prototype.onMapResize.apply(this, arguments);
        this.renderer.setSize(this.map.getSize());
    },
 
    /**
     * Method: moveTo
     *  Reset the vector layer's div so that it once again is lined up with 
     *   the map. Notify the renderer of the change of extent, and in the
     *   case of a change of zoom level (resolution), have the 
     *   renderer redraw features.
     * 
     *  If the layer has not yet been drawn, cycle through the layer's 
     *   features and draw each one.
     * 
     * Parameters:
     * bounds - {<OpenLayers.Bounds>} 
     * zoomChanged - {Boolean} 
     * dragging - {Boolean} 
     */
    moveTo: function(bounds, zoomChanged, dragging) {
        OpenLayers.Layer.prototype.moveTo.apply(this, arguments);
        
        var coordSysUnchanged = true;
 
        if (!dragging) {
            this.renderer.root.style.visibility = "hidden";
            
            this.div.style.left = -parseInt(this.map.layerContainerDiv.style.left) + "px";
            this.div.style.top = -parseInt(this.map.layerContainerDiv.style.top) + "px";
            var extent = this.map.getExtent();
            coordSysUnchanged = this.renderer.setExtent(extent, zoomChanged);
            
            this.renderer.root.style.visibility = "visible";
 
            // Force a reflow on gecko based browsers to prevent jump/flicker.
            // This seems to happen on only certain configurations; it was originally
            // noticed in FF 2.0 and Linux.
            if (navigator.userAgent.toLowerCase().indexOf("gecko") != -1) {
                this.div.scrollLeft = this.div.scrollLeft;
            }
            
            if(!zoomChanged && coordSysUnchanged) {
                for(var i in this.unrenderedFeatures) {
                    var feature = this.unrenderedFeatures[i];
                    this.drawFeature(feature);
                }
            }
        }
        
        if (!this.drawn || zoomChanged || !coordSysUnchanged) {
      &nb