1 files changed, 60 insertions, 0 deletions
diff --git a/NesTiler/ColorsFinder.cs b/NesTiler/ColorsFinder.cs
new file mode 100644
index 0000000..2772f69
--- /dev/null
+++ b/NesTiler/ColorsFinder.cs
@@ -0,0 +1,60 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace com.clusterrr.Famicom.NesTiler
+{
+    class ColorsFinder 
+    {
+        private readonly Dictionary<byte, Color> colors;
+        private readonly Dictionary<Color, byte> cache = new();
+
+        public ColorsFinder(Dictionary<byte, Color> colors)
+        {
+            this.colors = colors;
+        }
+
+        public byte FindSimilarColor(Color color)
+        {
+            if (cache.ContainsKey(color))
+                return cache[color];
+            byte result = byte.MaxValue;
+            double minDelta = double.MaxValue;
+            Color c = Color.Transparent;
+            foreach (var index in colors.Keys)
+            {
+                var delta = color.GetDelta(colors[index]);
+                if (delta < minDelta)
+                {
+                    minDelta = delta;
+                    result = index;
+                    c = colors[index];
+                }
+            }
+            if (result == byte.MaxValue)
+                throw new KeyNotFoundException($"Invalid color: {color}.");
+            if (cache != null)
+                cache[color] = result;
+            return result;
+        }
+
+        public Color FindSimilarColor(IEnumerable<Color> colors, Color color)
+        {
+            Color result = Color.Black;
+            double minDelta = double.MaxValue;
+            foreach (var c in colors)
+            {
+                var delta = color.GetDelta(c);
+                if (delta < minDelta)
+                {
+                    minDelta = delta;
+                    result = c;
+                }
+            }
+            return result;
+        }
+    }
+}