Laravel: Condition of controller inside Ajax call

First I will put the code here.

This is my ajax code:

//View para crear proyecto
$("#myFormProject").submit(function(e){
    e.preventDefault();
    var formData = new FormData($(this)[0]);
    $.ajax({
        url:'/admin/projects/postUpload',
        type:'POST',
        data: formData,
        success: function(){
            $("#formcrearproyecto").fadeOut(1000);
            $("#formcreartraducciones").fadeIn(1000);
        },
        cache: false,
        contentType: false,
        processData: false
    });
    return false;
});

My controller function look like this:

public function storeProject(Request $request)
    {
    $clients = DB::table('clients')->orderBy('name','asc')->get();
    $projects = DB::table('projects')->get();
    $project = new Project();
    $project->slug = $request->input("slug");
    $project->order = DB::table('projects')
                  ->where('order', DB::raw("(select max(`order`) from projects)"))
                  ->first()
                  ->order + 1; 
    $project->public = 0;
    $imagen = getimagesize($request->file('pathheader'));
    $ancho = $imagen[0];
    $altura = $imagen[1];
    $maxancho = 1930;
    $minancho = 1910;
    $maxaltura = 822;
    $minaltura = 802;
    $imagen2 = getimagesize($request->file('pathhome'));
    $ancho2 = $imagen2[0];
    $altura2 = $imagen2[1];
    $maxancho2 = 778;
    $minancho2 = 358;
    $maxaltura2 = 355;
    $minaltura2 = 335;
    if ($ancho<$maxancho && $ancho>$minancho && $altura<$maxaltura && $altura>$minaltura &&
    $ancho2<$maxancho2 && $ancho2>$minancho2 && $altura2<$maxaltura2 && $altura2>$minaltura2){
    \Storage::disk('projects')->makeDirectory($project->slug);
    $project->pathheader = \Storage::disk('projects')->putFileAs($project->slug, $request->file('pathheader'),'header.jpg');
    $project->pathhome = \Storage::disk('projects')->putFileAs($project->slug, $request->file('pathhome'),'home.jpg');
    $project->save();
    File::put(resource_path('views/projects/').$project->slug.'.blade.php','');
    }
    else{
        Session::flash('warning','Las medidas de almenos una de las 2 imagenes no es la correcta.');
            return view('cms.public.views.projects.menu',['projects' => $projects, 'clients' => $clients]);
    }

}

The problem is when I submit a picture who don't enter in IF and go to ELSE equally make the fadeout and fadein.

How can I make a condition inside Ajax to check if enter in if or not, and make fadeout and fadein or just show the session::flash?

Thanks a lot.

via Chebli Mohamed