DataLoad

/*
    CASA Lib for ActionScript 3.0
    Copyright (c) 2011, Aaron Clinger & Contributors of CASA Lib
    All rights reserved.
    
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      this list of conditions and the following disclaimer.
    
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      this list of conditions and the following disclaimer in the documentation
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      may be used to endorse or promote products derived from this software
      without specific prior written permission.
    
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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*/
package org.casalib.load {
    import flash.events.IEventDispatcher;
    import flash.events.HTTPStatusEvent;
    import flash.events.SecurityErrorEvent;
    import flash.net.URLLoader;
    import flash.net.URLLoaderDataFormat;
    import flash.net.URLVariables;
    import org.casalib.load.LoadItem;
    import flash.utils.ByteArray;
    
    [Event(name="httpStatus", type="flash.events.HTTPStatusEvent")]
    [Event(name="securityError", type="flash.events.SecurityErrorEvent")]
    
    /**
        Provides an easy and standardized way to load data.
        
        @author Aaron Clinger
        @version 02/13/10
        @example
            
                package {
                    import org.casalib.display.CasaMovieClip;
                    import org.casalib.events.LoadEvent;
                    import org.casalib.load.DataLoad;
                    
                    
                    public class MyExample extends CasaMovieClip {
                        protected var _dataLoad:DataLoad;
                        
                        
                        public function MyExample() {
                            super();
                            
                            this._dataLoad = new DataLoad("data.xml");
                            this._dataLoad.addEventListener(LoadEvent.COMPLETE, this._onComplete);
                            this._dataLoad.start();
                        }
                        
                        protected function _onComplete(e:LoadEvent):void {
                            trace(this._dataLoad.dataAsXml.toXMLString());
                        }
                    }
                }
            
    */
    public class DataLoad extends LoadItem {
        
        
        /**
            Creates and defines a DataLoad.
            
            @param request: A String or an URLRequest reference to the file you wish to load.
            @param dataFormat: Sets whether the data is received as as text, raw binary data or URL-encoded variables; defaults to text.
            @throws ArguementTypeError if you pass a type other than a String or an URLRequest to parameter request.
            @throws Error if you try to load an empty String or URLRequest.
        */
        public function DataLoad(request:*, dataFormat:String = URLLoaderDataFormat.TEXT) {
            var urlLoader:URLLoader = new URLLoader();
            urlLoader.dataFormat    = dataFormat;
            
            super(urlLoader, request);
            
            this._initListeners(this._loadItem);
        }
        
        /**
            The URLLoader being used to download the data.
        */
        public function get urlLoader():URLLoader {
            return this._loadItem as URLLoader;
        }
        
        /**
            The data received from the DataLoad. Available after load is complete.
            
            @throws Error if method is called before the file has loaded.
        */
        public function get data():* {
            if (!this.loaded)
                throw new Error('Cannot access an external data until the file has loaded.');
            
            return this._loadItem.data;
        }
        
        /**
            The data type that DataLoad is receiving.
        */
        public function get dataFormat():String {
            return this._loadItem.dataFormat;
        }
        
        /**
            The data received from the DataLoad data typed as String. Available after load is complete.
            
            @throws Error if method is called before the file has loaded.
            @throws Error if method cannot convert data to a String.
        */
        public function get dataAsString():String {
            if (this.dataFormat == URLLoaderDataFormat.BINARY)
                throw new Error('Cannot convert data to a String.');
            
            if (this.dataFormat == URLLoaderDataFormat.VARIABLES)
                return this.data.toString();
            
            return this.data;
        }
        
        /**
            The data received from the DataLoad data typed as XML. Available after load is complete.
            
            @throws Error if method is called before the file has loaded.
            @throws Error if method cannot convert data to XML.
        */
        public function get dataAsXml():XML {
            if (this.dataFormat != URLLoaderDataFormat.TEXT)
                throw new Error('Cannot convert data to XML.');
            
            return new XML(this.data);
        }
        
        /**
            The data received from the DataLoad data typed as URLVariables. Available after load is complete.
            
            @throws Error if method is called before the file has loaded.
            @throws Error if method cannot convert data to URLVariables.
        */
        public function get dataAsUrlVariables():URLVariables {
            if (this.dataFormat == URLLoaderDataFormat.BINARY)
                throw new Error('Cannot convert data to URLVariables.');
            
            if (this.dataFormat == URLLoaderDataFormat.TEXT)
                return new URLVariables(this.data);
            
            return this.data;
        }
        
        /**
            The data received from the DataLoad data typed as ByteArray. Available after load is complete.
            
            @throws Error if method is called before the file has loaded.
            @throws Error if method cannot convert data to a ByteArray.
        */
        public function get dataAsByteArray():ByteArray {
            if (this.dataFormat != URLLoaderDataFormat.BINARY)
                throw new Error('Cannot convert data to a ByteArray.');
            
            return this.data;
        }
        
        override public function destroy():void {
            this._dispatcher.removeEventListener(HTTPStatusEvent.HTTP_STATUS, this._onHttpStatus);
            this._dispatcher.removeEventListener(SecurityErrorEvent.SECURITY_ERROR, this.dispatchEvent);
            
            super.destroy();
        }
        
        /**
            @sends HTTPStatusEvent#HTTP_STATUS - Dispatched if class is able to detect and return the status code for the request.
            @sends SecurityErrorEvent#SECURITY_ERROR - Dispatched if load is outside the security sandbox.
        */
        override protected function _initListeners(dispatcher:IEventDispatcher):void {
            super._initListeners(dispatcher);
            
            this._dispatcher.addEventListener(HTTPStatusEvent.HTTP_STATUS, this._onHttpStatus, false, 0, true);
            this._dispatcher.addEventListener(SecurityErrorEvent.SECURITY_ERROR, this.dispatchEvent, false, 0, true);
        }
    }
}