How to Apply Color to Specific Text in Photoshop scripts

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// apply properties like color to letters of words in selected type layer;
// 2024, use it at your own risk;
if (app.documents.length > 0) {
    var theRegExp = /ipsum/gi;
	changeWordProperties (theRegExp)
};
//////////////////
////// change word properties //////
function changeWordProperties (theRegExp) {
var originalRulerUnits = app.preferences.rulerUnits;
app.preferences.rulerUnits = Units.PIXELS;
//////////////////
try {
var theFonts = new Array;
var theStyleRanges = new Array;
var theStyleRanges2 = new Array;
// get font of active layer;
var ref = new ActionReference();
ref.putEnumerated( charIDToTypeID("Lyr "), charIDToTypeID("Ordn"), charIDToTypeID("Trgt") ); 
var layerDesc = executeActionGet(ref);
var layerSet = typeIDToStringID(layerDesc.getEnumerationValue(stringIDToTypeID("layerSection")));
var isBackground = layerDesc.getBoolean(stringIDToTypeID("background"));
var theName = layerDesc.getString(stringIDToTypeID('name'));
// if not layer group collect values;
if (layerSet != "layerSectionEnd" && layerSet != "layerSectionStart" && isBackground != true) {
var hasText = layerDesc.hasKey(stringIDToTypeID("textKey"));
if (hasText == true) {
var textDesc = layerDesc.getObjectValue(stringIDToTypeID('textKey'));
var theText = textDesc.getString(stringIDToTypeID('textKey'));
// get indices for string;
var indicesCount = 0;
var theIndices = new Array;
while ((result = theRegExp.exec(theText))!=null) {
    theIndices.push([result.index, result.index+result[0].length])
};
//alert ("\n"+theIndices.join("\n"));
//var shapeList = textDesc.getList(stringIDToTypeID('textShape'));
var paragraphRangeList = textDesc.getList(stringIDToTypeID('paragraphStyleRange'));
var kernRange = textDesc.getList(stringIDToTypeID('kerningRange'));
var rangeList = textDesc.getList(stringIDToTypeID('textStyleRange'));
// process the list;
for (var o = 0; o < rangeList.count; o++) {
var thisList = rangeList.getObjectValue(o);
var theFrom = thisList.getInteger(stringIDToTypeID('from'));
var theTo = thisList.getInteger(stringIDToTypeID('to'));
var styleDesc = thisList.getObjectValue(stringIDToTypeID('textStyle'));
var aSize = styleDesc.getUnitDoubleValue(charIDToTypeID( "Sz  " ));
// check for default font;
if (styleDesc.hasKey(stringIDToTypeID('fontPostScriptName')) == true) {var aFont = styleDesc.getString(stringIDToTypeID('fontPostScriptName'))}
else {
	var theDefault = styleDesc.getObjectValue(stringIDToTypeID('baseParentStyle'));	
	var aFont = theDefault.getString(stringIDToTypeID('fontPostScriptName'));
	};
if (styleDesc.hasKey(stringIDToTypeID('impliedFontSize')) == true) {var aFont = styleDesc.getString(stringIDToTypeID('fontPostScriptName'))}
// add to array;
theFonts.push([aFont, aSize, theFrom, theTo]);
theStyleRanges.push(thisList.getObjectValue(stringIDToTypeID('textStyle')));
theStyleRanges2.push(thisList.getObjectValue(stringIDToTypeID('textStyle')));
}
}
};
// the change arrays;
var theColors = [[255,0,0]];
// change text;
var idPxl = charIDToTypeID( "#Pxl" );
var idPnt = charIDToTypeID( "#Pnt" );
var idTxtt = charIDToTypeID( "Txtt" );
var idFrom = charIDToTypeID( "From" );
var idT = charIDToTypeID( "T   " );
var idTxtS = charIDToTypeID( "TxtS" );
var idTxLr = charIDToTypeID( "TxLr" );
var idTxt = charIDToTypeID( "Txt " );
var idsetd = charIDToTypeID( "setd" );
    var desc6 = new ActionDescriptor();
    var idnull = charIDToTypeID( "null" );
        var ref1 = new ActionReference();
        ref1.putEnumerated( idTxLr, charIDToTypeID( "Ordn" ), charIDToTypeID( "Trgt"  ));
    desc6.putReference( idnull, ref1 );
        var desc7 = new ActionDescriptor();
        desc7.putString( idTxt, theText );
            var list2 = new ActionList();
//////////////////////////////////////////////////////
// define each letter individually;
var theIndex = 0;
var theRef = theStyleRanges[theIndex];
var theRef2 = theFonts[theIndex];
var theSize = theStyleRanges[theIndex].getUnitDoubleValue(charIDToTypeID( "Sz  " ));
var targetStart = theIndices[indicesCount][0];
var targetEnd = theIndices[indicesCount][1];
for (var m = 0; m < theText.length; m++) {
// check for relevant style range;
		if (m == theRef2[3]) {
			theIndex++;
			var theRef = theStyleRanges[theIndex];
			var theRef2 = theFonts[theIndex];
			var theSize = theStyleRanges[theIndex].getUnitDoubleValue(charIDToTypeID( "Sz  " ));
			};
		var desc14 = new ActionDescriptor();
		desc14.putInteger( idFrom, m );
		desc14.putInteger( idT, m+1 );
		var theStyle = theRef;
// the changes;
        if (m >= targetStart && m < targetEnd) {
// color;
            anIndex = Math.floor(Math.random() * (theColors.length));
            var desc21 = new ActionDescriptor();
            desc21.putDouble( charIDToTypeID( "Rd  " ), theColors[0][0] );
            desc21.putDouble( charIDToTypeID( "Grn " ), theColors[0][1]  );
            desc21.putDouble( charIDToTypeID( "Bl  " ), theColors[0][2]  );
            theStyle.putObject( charIDToTypeID( "Clr " ), charIDToTypeID( "RGBC" ), desc21 );
            desc14.putObject( idTxtS, idTxtS, theStyle);
        } else {
            desc14.putObject( idTxtS, idTxtS, theStyleRanges2[theIndex]);
            if (m == targetEnd && indicesCount < theIndices.length-1) {
                indicesCount++;
                var targetStart = theIndices[indicesCount][0];
                var targetEnd = theIndices[indicesCount][1];
            }
        };
        list2.putObject( charIDToTypeID( "Txtt" ),  desc14);
		};
//////////////////////////////////////////////////////
var list3 = new ActionList();
for (var n = 0; n < kernRange.count; n++) {
var thisOne = kernRange.getObjectValue(n);
var desc15 = new ActionDescriptor();
desc15.putInteger( idFrom, thisOne.getInteger(charIDToTypeID("From")) );
desc15.putInteger( idT, thisOne.getInteger(charIDToTypeID( "T   " )) );
desc15.putInteger( charIDToTypeID( "Krng" ), thisOne.getInteger(stringIDToTypeID("kerning")));
list3.putObject( stringIDToTypeID( "kerningRange"),  desc15);
};
        desc7.putList( idTxtt, list2 );
        desc7.putList( stringIDToTypeID( "kerningRange"), list3);
    desc6.putObject( idT, idTxLr, desc7 );
executeAction( idsetd, desc6, DialogModes.NO );
}
catch (e) {};
app.preferences.rulerUnits = originalRulerUnits;
};