Process

/*
    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.
    
    - Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    
    - Neither the name of the CASA Lib nor the names of its contributors
      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
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    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.process {
    import org.casalib.control.IRunnable;
    import org.casalib.events.RemovableEventDispatcher;
    import org.casalib.events.ProcessEvent;
    
    [Event(name="processStart", type="org.casalib.events.ProcessEvent")]
    [Event(name="processStop", type="org.casalib.events.ProcessEvent")]
    [Event(name="processComplete", type="org.casalib.events.ProcessEvent")]
    
    /**
        Base process class. Process is not designed to be used on its own and needs to be extended to function.
        
        @author Aaron Clinger
        @version 02/11/10
    */
    public class Process extends RemovableEventDispatcher implements IRunnable {
        public static var NORM_PRIORITY:int = 0; /**< The default priority for all Process instances. */
        protected var _priority:uint;
        protected var _isRunning:Boolean;
        protected var _hasCompleted:Boolean;
        
        
        /**
            Creates a new Process.
        */
        public function Process() {
            super();
            
            this.priority = Process.NORM_PRIORITY;
        }
        
        /**
            @sends ProcessEvent#START - Dispatched when process starts.
        */
        public function start():void {
            this._isRunning    = true;
            this._hasCompleted = false;
            
            this.dispatchEvent(new ProcessEvent(ProcessEvent.START));
        }
        
        /**
            @sends ProcessEvent#STOP - Dispatched when process is stopped.
        */
        public function stop():void {
            this._isRunning = false;
            
            this.dispatchEvent(new ProcessEvent(ProcessEvent.STOP));
        }
        
        /**
            Determines if the process is currently running true, or if it isn't false.
        */
        public function get running():Boolean {
            return this._isRunning;
        }
        
        /**
            Determines if the process has completed true, or if it hasn't false.
        */
        public function get completed():Boolean {
            return this._hasCompleted;
        }
        
        /**
            The priority relative to other processes. The higher priority processes will take precedence over lower priority processes in a {@link ProcessGroup}.
        */
        public function get priority():int {
            return this._priority;
        }
        
        public function set priority(priority:int):void {
            this._priority = priority;
        }
        
        override public function destroy():void {
            if (this.running)
                this.stop();
            
            super.destroy();
        }
        
        /**
            @sends ProcessEvent#COMPLETE - Dispatched when process completes.
        */
        protected function _complete():void {
            this._isRunning    = false;
            this._hasCompleted = true;
            
            this.dispatchEvent(new ProcessEvent(ProcessEvent.COMPLETE));
        }
    }
}