var fullName = "Wojciech Zachwieja";
var date = new Date();
var d  = date.getDate();  
var day = (d < 10) ? '0' + d : d;  
var m = date.getMonth() + 1;  
var month = (m < 10) ? '0' + m : m;  
var yy = date.getYear();  
var year = (yy < 1000) ? yy + 1900 : yy;  
var content = fullName + " , " +  day + '-' + month + '-' + year;

createText(42, content)
activeDocument.activeLayer.name = "Text";
activeDocument.activeLayer.textItem.justification = Justification.CENTER;

function createText(size, content)
{
  // Add a new layer in the new document
  var artLayerRef = app.activeDocument.artLayers.add();

  // Specify that the layer is a text layer
  artLayerRef.kind = LayerKind.TEXT;

  //This section defines the color of the hello world text
//  textColor = new SolidColor();
//  textColor.rgb.red = 0;
//  textColor.rgb.green = 0;
//  textColor.rgb.blue = 0;

  //Get a reference to the text item so that we can add the text and format it a bit
  textItemRef = artLayerRef.textItem
  textItemRef.contents = content;
 // textItemRef.color = textColor;
 // textItemRef.size = size;

  textItemRef.position = new Array(15, 10); //pixels from the left, pixels from the top
}