MpdResponse refactored (partial)

LibMpc/Message/MpdResponseState.cs

@@ -0,0 +1,63 @@
+using System.Text.RegularExpressions;
+
+namespace LibMpc
+{
+    public interface IMpdResponseState
+    {
+        string Status { get; }
+        string ErrorMessage { get; }
+        string MpdError { get; }
+        bool IsError { get; }
+    }
+
+    public class MpdResponseState : IMpdResponseState
+    {
+        private static readonly Regex ErrorPattern = new Regex("^ACK \\[(?<code>[0-9]*)@(?<nr>[0-9]*)] \\{(?<command>[a-z]*)} (?<message>.*)$");
+
+        private readonly string _endLine;
+
+        public MpdResponseState(string endLine)
+        {
+            _endLine = endLine;
+
+            if (!string.IsNullOrEmpty(_endLine))
+            {
+                if (_endLine.Equals(Constants.Ok))
+                {
+                    Status = _endLine;
+                    IsError = false;
+                }
+                else
+                {
+                    ParseErrorResponse();
+                }
+            }
+        }
+
+        public bool IsError { get; private set; } = true;
+        public string Status { get; private set; } = "UNKNOWN";
+        public string ErrorMessage { get; private set; } = string.Empty;
+        public string MpdError { get; private set; } = string.Empty;
+
+        private void ParseErrorResponse()
+        {
+            Status = "ERROR";
+            MpdError = _endLine;
+
+            var match = ErrorPattern.Match(_endLine);
+
+            if (match.Groups.Count != 5)
+            {
+                ErrorMessage = "Unexpected response from server.";
+            }
+            else
+            {
+                var errorCode = match.Result("${code}");
+                var commandListItem = match.Result("${nr}");
+                var commandFailed = match.Result("${command}");
+                var errorMessage = match.Result("${message}");
+                ErrorMessage = $"ErrorCode: { errorCode }, CommandListItem: { commandListItem }, CommandFailed: { commandFailed }, ErrorMessage: { errorMessage }";
+            }
+        }
+    }
+}