StreamInfo.as

   1 package  {
   2         import flash.events.Event;
   3         import flash.events.EventDispatcher;
   4         import flash.utils.setInterval;
   5         import flash.net.*
   6
   7         public class StreamInfo extends EventDispatcher {
   8                 private var request:URLRequest;
   9                 private var loader:URLLoader;
  10                 private var streamInfo = {};
  11                 private var lastUpdated:Array;
  12                 private var section:String;
  13                 private var fileLock = false;
  14                 private var loadCallback:Function;
  15
  16                 public static const INFO_UPDATE = "info_update";
  17
  18                 public function StreamInfo(section:String, refreshRate:int) {
  19                         this.request = new URLRequest("StreamInfo.txt");
  20                         this.loader = new URLLoader();
  21                         this.section = section;
  22                         setInterval(this.parse, refreshRate);
  23                 }
  24
  25                 public function parse() {
  26                         if(!this.fileLock) {
  27                                 this.loadCallback = this.onLoaded(this);
  28
  29                                 loader.addEventListener(Event.COMPLETE, this.loadCallback);
  30                                 this.fileLock = true;
  31                                 this.loader.load(this.request);
  32                         } else {
  33                                 trace("Lock active, not doing anything.");
  34                         }
  35                 }
  36
  37                 public function getStreamParameter(name:String) {
  38                         return this.streamInfo[name];
  39                 }
  40
  41                 public function getLastUpdated():Array {
  42                         return this.lastUpdated;
  43                 }
  44
  45                 private function releaseLock() {
  46                         this.fileLock = false;
  47                 }
  48
  49                 private function onLoaded(streamInfo:StreamInfo):Function {
  50                         return function(e:Event):void {
  51                                 //Deal with windows style line endings, and tabs.
  52                                 var lines = streamInfo.loader.data.replace(/(\t|\r)/gi, "").split("\n");
  53                                 var sectionLines:Array = streamInfo.extractSection(lines);
  54                                 streamInfo.parseVars(sectionLines);
  55                                 streamInfo.releaseLock();
  56                                 streamInfo.loader.removeEventListener(Event.COMPLETE, streamInfo.loadCallback);
  57                         }
  58                 }
  59
  60                 private function extractSection(lines:Array) {
  61                         var sectionLines:Array = new Array();
  62                         var foundFirstLineOfSection:Boolean = false;
  63                         for each(var line in lines) {
  64                                 foundFirstLineOfSection = !foundFirstLineOfSection ? line.indexOf("[" + this.section + "]") >= 0 : !line.match(/\[\w+\]/);
  65
  66                                 if(foundFirstLineOfSection) {
  67                                         sectionLines.push(line);
  68                                 }
  69                         }
  70
  71                         return sectionLines;
  72                 }
  73
  74                 private function parseVars(lines:Array) {
  75                         var broadcastUpdate = false;
  76                         for each(var line in lines) {
  77                                 var keyValue = line.split("=", 2).map(Util.trim);
  78                                 if(keyValue.length == 2) {
  79                                         if(this.streamInfo[keyValue[0]] != keyValue[1]) {
  80                                                 if(!broadcastUpdate) {
  81                                                         this.lastUpdated = new Array();
  82                                                 }
  83
  84                                                 broadcastUpdate = true;
  85
  86                                                 this.lastUpdated.push(keyValue[0]);
  87                                                 this.streamInfo[keyValue[0]] = keyValue[1];
  88                                         }
  89                                 }
  90                         }
  91
  92                         if(broadcastUpdate) {
  93                                 this.dispatchEvent(new Event(INFO_UPDATE));
  94                         }
  95                 }
  96         }
  97 }