net/systemeD/halcyon/styleparser/Condition.as

   1 package net.systemeD.halcyon.styleparser {
   2
   3         /**     A single tag test that forms part of a MapCSS selector.
   4                 For example, "highway==primary" or "population>1000".
   5                 Conditions are grouped in Rules.
   6
   7                 @see net.systemeD.halcyon.styleparser.Rule */
   8
   9         public class Condition {
  10                 public var type:String;
  11                 public var params:Array;
  12
  13                 /** Create a new Condition.                                                                                                             <p>
  14
  15                         Valid types:                                                                                                                    </p><p>
  16                         eq,'highway','trunk'            - simple equality test                                          </p><p>
  17                         ne,'highway','trunk'            - not equals                                                            </p><p>
  18                         regex,'highway','trunk.+'       - regular expression                                            </p><p>
  19                         true,'bridge'                           - value is true/yes/1                                           </p><p>
  20                         untrue,'bridge'                         - value is not true/yes/1                                       </p><p>
  21                         set,'highway'                           - tag exists and is not ''                                      </p><p>
  22                         unset,'highway'                         - tag does not exist, or is ''                          </p><p>
  23                         <,'population','5000'           - numeric comparison (also <=, >, >=)           </p>
  24                  */
  25
  26                 public function Condition(type:String='', ...params) {
  27                         this.type=type; this.params=params;
  28                 }
  29
  30                 /** Test a tag hash against the Condition. */
  31
  32                 public function test(tags:Object):Boolean {
  33                         switch (type) {
  34                                 case 'eq':              return (tags[params[0]]==params[1]); break;
  35                                 case 'ne':              return (tags[params[0]]!=params[1]); break;
  36                                 case 'regex':   var r:RegExp=new RegExp(params[1],"i");
  37                                                                 return (r.test(tags[params[0]])); break;
  38                                 case 'true':    return (tags[params[0]]=='true' || tags[params[0]]=='yes' || tags[params[0]]=='1'); break;
  39                                 case 'false':   return (tags[params[0]]=='false' || tags[params[0]]=='no' || tags[params[0]]=='0'); break;
  40                                 case 'set':             return (tags[params[0]]!=undefined && tags[params[0]]!=''); break;
  41                                 case 'unset':   return (tags[params[0]]==undefined || tags[params[0]]==''); break;
  42                                 case '<':               return (Number(tags[params[0]])< Number(params[1])); break;
  43                                 case '<=':              return (Number(tags[params[0]])<=Number(params[1])); break;
  44                                 case '>':               return (Number(tags[params[0]])> Number(params[1])); break;
  45                                 case '>=':              return (Number(tags[params[0]])>=Number(params[1])); break;
  46                         }
  47                         return false;
  48                 }
  49
  50         public function toString():String {
  51             return "Condition("+type+":"+params+")";
  52         }
  53
  54
  55         }
  56
  57 }