fsm.html

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   3 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
   4 <head>
   5     <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/>
   6     <link rel="stylesheet" href="style/pixelless.css" type="text/css"/>
   7     <script type="text/javascript" src="script/util.js"></script>
   8     <title>Finite State Automata</title>
   9 </head>
  10 <body>
  11 <div id="container">
  12     <div class="content header">
  13         <h1>Finite State Automata</h1>
  14     </div>
  15
  16     <div class="content">
  17
  18     </div>
  19 </div>
  20 <div id="footer">
  21     <div class="content">
  22         &copy; Copyright
  23     </div>
  24 </div>
  25 <script type="text/javascript" language="JavaScript">
  26     function Fsm( state )
  27     {
  28         this.transitions = {};
  29         this.handlers = {};
  30
  31         this.current = state;
  32         this.previous = null;
  33
  34         this.state = {};
  35     }
  36
  37     Fsm.prototype.addTransition = function( from, to, event )
  38     {
  39         if( !(from in this.transitions) )
  40             this.transitions[from] = {};
  41
  42         if( event in this.transitions[from] && this.transitions[from][event] != to )
  43             throw new Error('Cannot add conflicting transition.');
  44
  45         this.transitions[from][event] = to;
  46
  47
  48     };
  49
  50     Fsm.prototype.turnFrom = function( state )
  51     {
  52         return new TransitionHint(this, state);
  53     };
  54
  55     Fsm.prototype.on = function( state, handler )
  56     {
  57         this.handlers[state] = handler;
  58     };
  59
  60     Fsm.prototype.handle = function( event )
  61     {
  62         if( event in this.transitions[this.current] )
  63         {
  64
  65             this.previous = this.current;
  66             this.current = this.transitions[this.current][event];
  67
  68             if( this.current in this.handlers )
  69             {
  70                 try {
  71                     this.handlers[this.current].call(this.state, this.state);
  72                 }
  73                 catch( ex )
  74                 {
  75                     if( console !== null )console.log(ex);
  76                 }
  77             }
  78         }
  79     };
  80
  81     function TransitionHint( fsm, state )
  82     {
  83         this.fsm = fsm;
  84         this.startState = state;
  85     }
  86
  87     TransitionHint.prototype.to = function( state )
  88     {
  89         return new Transition(this.fsm, this.startState, state);
  90     };
  91
  92     function Transition( fsm, startState, endState )
  93     {
  94         this.fsm = fsm;
  95         this.startState = startState;
  96         this.endState = endState;
  97     }
  98
  99     Transition.prototype.on = function( event )
 100     {
 101         this.fsm.addTransition(this.startState, this.endState, event);
 102         return new TransitionHint(this.fsm, this.endState);
 103     };
 104
 105     var bot = new Fsm('seeking');
 106
 107     bot.turnFrom('seeking')
 108             .to('attacking').on('target_encountered')
 109             .to('fleing').on('health_low');
 110
 111     bot.on('attacking', function( state ) {
 112         if( this != state )
 113             console.log('noooooo');
 114         else
 115             console.log('yes.');
 116     });
 117
 118     bot.handle('target_encountered');
 119
 120 </script>
 121 </body>
 122 </html>