Implemented gif exportation and added some style (again)

GifResizer/Models/Gif.cs

@@ -1,6 +1,4 @@
-using System.Diagnostics;
-using System.IO;
-using GifResizer.Service;
+using System.IO;
 using SixLabors.ImageSharp;
 using SixLabors.ImageSharp.Processing;
 
@@ -9,7 +7,7 @@ namespace GifResizer.Models;
 public class Gif : IDisposable
 {
 
-    private readonly FileInfo _file;
+    private readonly string _path;
     private Image? _image;
     
     public Gif(string path)
@@ -17,18 +15,19 @@ public class Gif : IDisposable
         ArgumentNullException.ThrowIfNull(path);
         if (path.Length == 0 || path.IsWhiteSpace() || !File.Exists(path)) 
             throw new ArgumentException($"File '{path}' does not exist");
-        
-        _file = new FileInfo(path);
+        _path = path;
     }
 
     public void Load()
     {
-        _image = Image.Load(_file.FullName);
+        _image = Image.Load(_path);
     }
     
     public void Resize(int width, int height)
     {
         if(_image == null) throw new InvalidOperationException("Image hasn't been loaded yet");
+        if(width <= 0 || height <= 0) throw new InvalidOperationException("Please specify a valid width or height.");
+        if(width == _image.Width && height == _image.Height) return;
         _image.Mutate(x => x.Resize(width, height));
     }