change save to jpg to tiff

I found a script that allows to crop and straighten scanned photos. However, there are 2 changes I want to make:

(1) Instead of being saved as jpegs, I want to resulting files to be saved as tiff

(2) Right now, it only looks at one level in a folder. I want it to dig into all subfolders as well. Is that possible?

#target Photoshop 

app.bringToFront; 

var inFolder = Folder.selectDialog("Please select folder to process");  

if(inFolder != null){ 

var fileList = inFolder.getFiles(/\.(jpg|jpeg|png|tif|tiff|psd|)$/i); 

var outfolder = new Folder(decodeURI(inFolder) + "/Edited"); 

if (outfolder.exists == false) outfolder.create(); 

for(var a = 0 ;a < fileList.length; a++){ 

if(fileList[a] instanceof File){ 

var doc= open(fileList[a]); 

doc.flatten(); 

var docname = fileList[a].name.slice(0,-4); 

CropStraighten(); 

doc.close(SaveOptions.DONOTSAVECHANGES);  

var count = 1; 

while(app.documents.length){ 

var saveFile = new File(decodeURI(outfolder) + "/" + docname +"#"+ zeroPad(count,3) + ".jpg"); 

SaveJPEG(saveFile, 12); 

activeDocument.close(SaveOptions.DONOTSAVECHANGES) ;  

count++; 

  } 

} 

} 

}; 

function CropStraighten() { 

executeAction( stringIDToTypeID('CropPhotosAuto0001'), undefined, DialogModes.NO ); 

}; 

function SaveJPEG(saveFile, jpegQuality){ 

jpgSaveOptions = new JPEGSaveOptions(); 

jpgSaveOptions.embedColorProfile = true; 

jpgSaveOptions.formatOptions = FormatOptions.STANDARDBASELINE; 

jpgSaveOptions.matte = MatteType.NONE; 

jpgSaveOptions.quality = jpegQuality;  

activeDocument.saveAs(saveFile, jpgSaveOptions, true,Extension.LOWERCASE); 

} 

function zeroPad(n, s) {  

n = n.toString();  

while (n.length < s) n = '0' + n;  

return n;  

};