Save As PNG script

Hello,

I'd like some help with this script if possible

I wanted to save my open file to PNG format in the same location with the same name. I managed to do that with the scripts below.

This is a script I found on the forum:

#target photoshop
main();
function main(){
if(!documents.length) return;
try{
    var Path = decodeURI(activeDocument.path.parent);
    }catch(e){return;}
if(!Folder(Path).exists){
    alert(Path + " Does not exist!");
    return;
    }
var Name = decodeURI(app.activeDocument.name).replace(/\.[^\.]+$/, '');
var saveFile = File(Path + "/" + Name + "_bump.png");
sfwPNG24(saveFile);
//Uncomment the line below if you want to close the document.
//app.activeDocument.close(SaveOptions.DONOTSAVECHANGES);
}
function sfwPNG24(saveFile){
var pngOpts = new ExportOptionsSaveForWeb;
pngOpts.format = SaveDocumentType.PNG
pngOpts.PNG8 = false;
pngOpts.transparency = true;
pngOpts.interlaced = false;
pngOpts.quality = 100;
activeDocument.exportDocument(new File(saveFile),ExportType.SAVEFORWEB,pngOpts);
} 

And this is how I modified it (so that it saves the file in the same folder and doesn't add any suffix to the name; also changed to save as PNG instead of using save for web):

#target photoshop
main();
function main(){
if(!documents.length) return;
try{
    var Path = decodeURI(activeDocument.path);
    }catch(e){return;}
if(!Folder(Path).exists){
    alert(Path + " Does not exist!");
    return;
    }
var Name = decodeURI(app.activeDocument.name).replace(/\.[^\.]+$/, '');
var saveFile = File(Path + "/" + Name + ".png");
sfwPNG24(saveFile);
//Uncomment the line below if you want to close the document.
//app.activeDocument.close(SaveOptions.DONOTSAVECHANGES);
}
function sfwPNG24(saveFile){
var pngOpts = new PNGSaveOptions;
pngOpts.compression = 9;
pngOpts.interlaced = false;
activeDocument.saveAs(saveFile, pngOpts, true, Extension.LOWERCASE); 
}

My problem:

I don't know what's happening when I try to save a file just created (never saved yet). I thought I would get the Alert message but it doesn't seem to be the case (maybe the alert message in the code is related to a different condition?)

I would like to have a default folder/path in the code so that, if the file hasn't been saved yet, it would be saved in the specified location.

If anyone could do it I would really appreciate it!

Thanks