Dynmically create pattern

I’ve finally worked out how to create a pattern dynamically so that it can be used in the same script.
I used to think that you had to supply the pattern ID or the name - but never got it to work always relying on the ID - which you can’t seem to get dynamically.

So for my future self:
 

// Switch off any dialog boxes
displayDialogs = DialogModes.ERROR; // OFF

var srcDoc = app.activeDocument;

// var pattern = "knitting 32 x 32";
// var pattern = "200 x 200";
// var pattern = "efa405da-f126-8b45-a46d-bb2228c1f124";
var pattern = "bananas"

//select all
activeDocument.selection.selectAll();


// save pattern 
save_pattern(pattern);

// TEMP add new layer
// =======================================================
var idMk = charIDToTypeID( "Mk  " );
var desc6963 = new ActionDescriptor();
var idnull = charIDToTypeID( "null" );
var ref1222 = new ActionReference();
var idLyr = charIDToTypeID( "Lyr " );
ref1222.putClass( idLyr );
desc6963.putReference( idnull, ref1222 );
var idUsng = charIDToTypeID( "Usng" );
var desc6964 = new ActionDescriptor();
var idNm = charIDToTypeID( "Nm  " );
desc6964.putString( idNm, pattern);
var idLyr = charIDToTypeID( "Lyr " );
desc6963.putObject( idUsng, idLyr, desc6964 );
var idLyrI = charIDToTypeID( "LyrI" );
desc6963.putInteger( idLyrI, 34 );
executeAction( idMk, desc6963, DialogModes.NO );

// Finnaly fill with new pattern
fill_with_pattern(pattern);


// call the source document
var srcDoc = app.activeDocument;


function fill_with_pattern(patternnameorID, x, y)
{
   // fill with pattern name or id
   if (x == undefined) x = 0;
   if (y == undefined) y = 0;

   var regEx = (/([a-z0-9]{8}\-)([a-z0-9]{4}\-)([a-z0-9]{4}\-)([a-z0-9]{4}\-)([a-z0-9]{12})/m); //NOT global
   var result = patternnameorID.match(regEx);

   if (result != null)
   {
      // match! Therefore it's a ID
      var ID = "" + patternnameorID;
      // apply some name to the pattern
      var patternName = ID; // same as ID
     // alert(patternnameorID + "\nis a pattern ID");

   }
   else
   {
      // it's a pattern name
      var patternName = patternnameorID;
      var ID = undefined;
      //alert(patternnameorID + "\nis a pattern name");
   }

   try
   {

      // =======================================================
      var idFl = charIDToTypeID( "Fl  " );
      var desc2789 = new ActionDescriptor();
      var idFrom = charIDToTypeID( "From" );
      var desc2790 = new ActionDescriptor();
      var idHrzn = charIDToTypeID( "Hrzn" );
      var idPxl = charIDToTypeID( "#Pxl" );
      desc2790.putUnitDouble( idHrzn, idPxl, x ); // x
      var idVrtc = charIDToTypeID( "Vrtc" );
      var idPxl = charIDToTypeID( "#Pxl" );
      desc2790.putUnitDouble( idVrtc, idPxl, y ); // y
      var idPnt = charIDToTypeID( "Pnt " );
      desc2789.putObject( idFrom, idPnt, desc2790 );
      var idTlrn = charIDToTypeID( "Tlrn" );
      desc2789.putInteger( idTlrn, 0 );
      var idUsng = charIDToTypeID( "Usng" );
      var idFlCn = charIDToTypeID( "FlCn" );
      var idPtrn = charIDToTypeID( "Ptrn" );
      desc2789.putEnumerated( idUsng, idFlCn, idPtrn );
      var idPtrn = charIDToTypeID( "Ptrn" );
      var desc2791 = new ActionDescriptor();


      var idNm = charIDToTypeID( "Nm  " );
      desc2791.putString( idNm, patternName );

      if (ID != undefined)
      {   
         var idIdnt = charIDToTypeID( "Idnt" );
         desc2791.putString( idIdnt, ID ); // Pattern ID

      }
      // Otherwise skip ID part

      var idPtrn = charIDToTypeID( "Ptrn" );
      desc2789.putObject( idPtrn, idPtrn, desc2791 );
      executeAction( idFl, desc2789, DialogModes.NO );
   }
   catch(eek)
   {
      alert("unable to find " + patternnameorID);
   }

}


function save_pattern(patternstr)
{
   // =======================================================
   var idMk = charIDToTypeID( "Mk  " );
   var desc47 = new ActionDescriptor();
   var idnull = charIDToTypeID( "null" );
   var ref10 = new ActionReference();
   var idPtrn = charIDToTypeID( "Ptrn" );
   ref10.putClass( idPtrn );
   desc47.putReference( idnull, ref10 );
   var idUsng = charIDToTypeID( "Usng" );
   var ref11 = new ActionReference();
   var idPrpr = charIDToTypeID( "Prpr" );
   var idfsel = charIDToTypeID( "fsel" );
   ref11.putProperty( idPrpr, idfsel );
   var idDcmn = charIDToTypeID( "Dcmn" );
   var idOrdn = charIDToTypeID( "Ordn" );
   var idTrgt = charIDToTypeID( "Trgt" );
   ref11.putEnumerated( idDcmn, idOrdn, idTrgt );
   desc47.putReference( idUsng, ref11 );
   var idNm = charIDToTypeID( "Nm  " );
   desc47.putString( idNm, patternstr ); // pattern name here
   executeAction( idMk, desc47, DialogModes.NO );

}





// function SELECT RECTANGLE(top, left, bottom, right)
// --------------------------------------------------------
function select_rectangle(top, left, bottom, right)
{
  // Note: co-ordinates are same as script listener
  // and not so human-friendly as t,l,r,b.
  // deselect EVERYTHING first
  app.activeDocument.selection.deselect();

  // =======================================================
  var id1 = charIDToTypeID( "setd" );
  var desc1 = new ActionDescriptor();
  var id2 = charIDToTypeID( "null" );
  var ref1 = new ActionReference();
  var id3 = charIDToTypeID( "Chnl" );
  var id4 = charIDToTypeID( "fsel" );
  ref1.putProperty( id3, id4 );
  desc1.putReference( id2, ref1 );
  var id5 = charIDToTypeID( "T   " );
  var desc2 = new ActionDescriptor();
  var id6 = charIDToTypeID( "Top " );
  var id7 = charIDToTypeID( "#Pxl" );
  desc2.putUnitDouble( id6, id7, top );
  var id8 = charIDToTypeID( "Left" );
  var id9 = charIDToTypeID( "#Pxl" );
  desc2.putUnitDouble( id8, id9, left );
  var id10 = charIDToTypeID( "Btom" );
  var id11 = charIDToTypeID( "#Pxl" );
  desc2.putUnitDouble( id10, id11, bottom );
  var id12 = charIDToTypeID( "Rght" );
  var id13 = charIDToTypeID( "#Pxl" );
  desc2.putUnitDouble( id12, id13, right );
  var id16 = charIDToTypeID( "Rctn" );
  desc1.putObject( id5, id16, desc2 );

  executeAction( id1, desc1, DialogModes.NO );
}

It won’t appear to do much. Seemingly duplicate a layer. However, it’s actually creating and then saving and then using a pattern.

I’m impressed even if no one else is. :D