GaTech_cs4731_fsm3.fmn

//-------------------------------------------------//
//                                                 //
//                         FMN                     //
//                                                 //
//-------------------------------------------------//

// Original source is course material for cs4731 at Georgia Institute of Technology
// Author: Dr. Stephen Lee-Urban
// see https://www.cc.gatech.edu/~surban6/2016-cs4731/lectures/2016_06_02_DecisionMaking_FSM.pdf
 
#GaTech_cs4731_fsm3

        -interface-
	
        no_percept
        predator
        no_predator
        hungry
        hungry_food
	
    	-machine-
    
        $Idle
		|predator| ->> $Flee ^
		|hungry| ->> $FindFood ^
                
        $Search => $FindFood 
		|hungry_food| ->> $Eat ^
            
        $Eat => $FindFood
		|hungry| ->> $Search ^
 
        $FindFood
		|predator| ->> $Flee ^
		|no_percept| ->> $Idle ^

        $Run => $Flee
		|hungry_food| ->> $RunSearch ^
 
        $RunSearch => $Flee
		|hungry| ->> $Run ^
 
        $Flee
		|no_percept| ->> $Idle ^
		|no_predator| ->> $FindFood ^

      

 //-------------------------------------------------//
 //                                                 //
 //                 Implementation                  //
 //                                                 //
 //-------------------------------------------------//
  
 class FrameEvent {
 
   var _msg:String
   var _params:Object
   var _return:Object
   
   FrameEvent(msg:String, params:Object = null) {
      _msg = msg
      _params = params
   }
}

 //-------------------------------------------------//

 class GaTech_cs4731_fsm3 {

	/**********************************
	
    	-interface-
	
        predator
        predator_hungry
        hungry
        hungry_food

        ***********************************/

	func predator() { _state(new FrameEvent("predator")) }
	func predator_hungry() { _state(new FrameEvent("predator_hungry")) }
	func hungry() { _state(new FrameEvent("hungry")) }
	func hungry_food() { _state(new FrameEvent("hungry_food")) }
	
   	// -machine-
    
   	var _state(e:FrameEvent) = Idle
    
	/**********************************
	
        $Idle
		|predator| ->> $Flee ^
		|hungry_food| ->> $Eat ^
		|hungry| ->> $Search ^

        ***********************************/
    
	func GatherTreasure(e:FrameEvent) {
		if (e._msg == "monsterInSight") {
		    _state = Flee
		    return
		}
	}
    
	/**********************************
                
        $Flee 
		|predator_hungry| ->> $FleeSearch ^
            
	***********************************/
    
	func Flee(e:FrameEvent) {
		if (e._msg == "predator_hungry") {
		    _state = FleeSearch
		    return
		}
	}  

	/**********************************
            
        $Search
		|predator| ->> $Flee ^
		|hungry_food| ->> $Eat ^
		|predator_hungry| ->> $FleeSearch ^
      
       ***********************************/

	func Search(e:FrameEvent) {
		if (e._msg == "predator") {
		    _state = Flee
		    return
		}
		if (e._msg == "hungry_food") {
		    _state = Eat
		    return
		}
                if (e._msg == "predator_hungry") {
		    _state = FleeSearch
		    return
		}
        }  

	/**********************************
            
        $Eat
		|predator| ->> $Flee ^
 		|hungry| ->> $Search ^
                   
       ***********************************/

	func Eat(e:FrameEvent) {
		if (e._msg == "predator") {
		    _state = Flee
		    return
		}
		if (e._msg == "hungry") {
		    _state = Search
		    return
		}
	} 
        
	/**********************************
          
        $FleeSearch
		|predator| ->> $Flee ^
       
       ***********************************/

	func FleeSearch(e:FrameEvent) {
		if (e._msg == "predator") {
		    _state = Flee
		    return
		}
	} 	
}