MpdResponse refactored (partial)

LibMpc/Message/MpdResponse.cs

@@ -0,0 +1,73 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.RegularExpressions;
+
+namespace LibMpc
+{
+    public interface IMpdResponse
+    {
+        IEnumerable<string> Response { get; }
+        IReadOnlyDictionary<string, string> Values { get; }
+        IMpdResponseState State { get; }
+    }
+
+    public class MpdResponse : IMpdResponse
+    {
+        private static readonly Regex LinePattern = new Regex("^(?<key>[A-Za-z]*):[ ]{0,1}(?<value>.*)$");
+
+        public MpdResponse(ICollection<string> response)
+        {
+            response.CheckNotNull();
+
+            var endLine = response.Take(response.Count - 2).Single();
+
+            Response = response.Take(response.Count - 2).ToList();
+            State = new MpdResponseState(endLine);
+            Values = GetValuesFromResponse();
+        }
+
+        public IMpdResponseState State { get; }
+
+        public IEnumerable<string> Response { get; }
+
+        public IReadOnlyDictionary<string, string> Values { get; }
+
+
+        private IReadOnlyDictionary<string, string> GetValuesFromResponse()
+        {
+            var result = new Dictionary<string, string>();
+
+            foreach (var line in Response)
+            {
+                var match = LinePattern.Match(line);
+                if (match.Success)
+                {
+                    var mpdKey = match.Result("${key}");
+                    if (!string.IsNullOrEmpty(mpdKey))
+                    {
+                        var mpdValue = match.Result("${value}");
+                        if (string.IsNullOrEmpty(mpdValue))
+                        {
+                            result.Add(mpdKey, mpdValue);
+
+                        }
+                    }
+                }
+            }
+
+            return result;
+        }
+    }
+
+    public static class CheckNotNullExtension
+    {
+        public static void CheckNotNull(this object toBeChecked)
+        {
+            if (toBeChecked == null)
+            {
+                throw new ArgumentNullException(nameof(toBeChecked));
+            }
+        }
+    }
+}