if (!window.ace) ace = {};

ace.BackgroundTokenizer = function(tokenizer, onUpdate, onComplete)
{
  this.running = false;
  this.textLines = [];
  this.lines = [];
  this.currentLine = 0;
  this.tokenizer = tokenizer;
  
  this.onUpdate = onUpdate || function(firstLine, lastLine) {};
  this.onComplete = onComplete || function() {};
  
  var self = this;
  this._worker = function() 
  {    
    if (!self.running) {
      return;
    }

    var workerStart = new Date();
    var startLine = self.currentLine;
    var textLines = self.textLines;

    var processedLines = 0;
    
    while (self.currentLine < textLines.length)
    {
      var line = textLines[self.currentLine];
      
      var state = self.currentLine == 0 ? "start" : self.lines[self.currentLine-1].state;      
      self.lines[self.currentLine] = self.tokenizer.getLineTokens(line, state);

      // only check every 30 lines
      processedLines += 1;
      if ((processedLines % 30 == 0) && (new Date()-workerStart) > 20)
      {
        self.onUpdate(startLine, self.currentLine);
        return setTimeout(self._worker, 10);
      }
      
      self.currentLine++;      
    }

    self.running = false;
    
    self.onUpdate(startLine, textLines.length-1);
    self.onComplete();    
  }
};

ace.BackgroundTokenizer.prototype.setLines = function(textLines)
{
  this.textLines = textLines;
  this.lines = [];
  
  this.stop();    
};

ace.BackgroundTokenizer.prototype.start = function(startRow)
{
  this.currentLine = Math.min(startRow || 0, this.currentLine, this.textLines.length);
  this.lines.splice(startRow, this.lines.length);

  if (!this.running)
  {
    this.running = true;
    setTimeout(this._worker, 50);
  }
};

ace.BackgroundTokenizer.prototype.stop = function() {
  this.running = false;
};

ace.BackgroundTokenizer.prototype.getTokens = function(row)
{
  if (this.lines[row]) {
    return this.lines[row].tokens;
  } else {
    var state = "start";
    if (row > 0 && this.lines[row-1]) {
      state = this.lines[row-1].state;
    }
    return this.tokenizer.getLineTokens(this.textLines[row] || "", state).tokens;
  }
};