Filtering files according to supported image types

src/NFT.net/Constants.cs

@@ -10,6 +10,7 @@ public static class Constants
         public const char WeightDelimiter = '+';
         public const string ImagesFolderName = "images";
         public const int MaxDuplicateDnaRetries = 100;
+        public static readonly string[] SupportedImageFormats = new[] { "*.jpg", "*.jpeg", "*.png" };
 
         public static class About
         {

src/NFT.net/NFT.net.csproj

@@ -7,7 +7,7 @@
 		<UseWindowsForms>true</UseWindowsForms>
 		<RootNamespace>Tedeschi.NFT</RootNamespace>
 		<AssemblyName>NFT.net</AssemblyName>
-		<Version>1.4.0</Version>
+		<Version>1.5.0</Version>
 		<Authors>Tedeschi</Authors>
 	</PropertyGroup>
 

src/NFT.net/Services/Layer/LayerService.cs

@@ -41,7 +41,7 @@ private List<Layer> HandleLayers(string[] folders)
                     throw new InvalidLayerNamingException(folder);
                 }
 
-                var files = Directory.GetFiles(folder);
+                var files = DirectoryUtil.GetFiles(folder, Constants.SupportedImageFormats, SearchOption.AllDirectories);
 
                 var elements = this.HandleElements(files, randomizer);
 

src/NFT.net/Util/DirectoryUtil.cs

@@ -0,0 +1,27 @@
+// <copyright file="DirectoryUtil.cs" company="Tedeschi">
+// Copyright (c) Tedeschi. All rights reserved.
+// </copyright>
+
+namespace Tedeschi.NFT.Util
+{
+    using System.IO;
+    using System.Linq;
+
+    public class DirectoryUtil
+    {
+        public static string[] GetFiles(string path, string[] patterns = null, SearchOption options = SearchOption.TopDirectoryOnly)
+        {
+            if (patterns == null || patterns.Length == 0)
+            {
+                return Directory.GetFiles(path, "*", options);
+            }
+
+            if (patterns.Length == 1)
+            {
+                return Directory.GetFiles(path, patterns[0], options);
+            }
+
+            return patterns.SelectMany(pattern => Directory.GetFiles(path, pattern, options)).Distinct().ToArray();
+        }
+    }
+}