Save as-funcion - help needed

Question

Hello,
The question is simple but the solution for me isn't so simple.
An eps-file in Illustrator must be saved as an ai-file with the same name, but the extension must be ai instead of the original eps-file.
Is it also possible to change the color profile from RGB/CMYK/... to grayscale?
The problem is that Illustrator saves the file as undefined.ai instead of the <<original file name>>.ai
#target illustrator
// PART 1 -> OK, this part works
var doc = app.activeDocument;
doc.artboards[0].artboardRect = doc.visibleBounds; //cropt de artboard naar enkel de figuurgrootte
// PART 2 -> don't work
var docName=doc.fullname;
destFolder = doc.path;
var destFile = new File(destFolder + "/" +  docName + ".ai");   // make a new file in the dest folder
var options = new IllustratorSaveOptions();   // new save as options
options.compatibility = Compatibility.ILLUSTRATOR15;   // save as AI CS5
options.pdfCompatible = true;
options.useCompression = false
doc.saveAs(destFile,  options);  // save the file in the same foldere as the eps
// PART 3 -> OK, this part works
doc.close(SaveOptions.SAVECHANGES);   // close the file with saving
// PART 4 -> change color profile?
I hope that someone can help.
Thanks

Answer 1

Try this:
#target illustrator
// PART 1 -> OK, this part works
var doc = app.activeDocument;
doc.artboards[0].artboardRect = doc.visibleBounds; //cropt de artboard naar enkel de figuurgrootte
// PART 2 ->
var destFile = new File(decodeURI(doc.fullName).replace(/(?: \[Converted\])?\.eps$/, '.ai'));   // also remove "[Converted]" from filename
var options = new IllustratorSaveOptions({});   // new save as options
options.compatibility = Compatibility.ILLUSTRATOR15;   // save as AI CS5
options.pdfCompatible = false;   //I don't like it
options.useCompression = true;   //I like it
doc.saveAs(destFile, options);   // save the file in the same foldere as the eps
// PART 3 -> OK, this part works
doc.close(SaveOptions.SAVECHANGES);   // close the file with saving
PART 4 -> change color profile
Do you mean change colorMode? But there is no grayscale colorMode.