initial commit, 4.5 stable

modules/mono/editor/GodotTools/GodotTools.IdeMessaging/MessageDecoder.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Text;
+
+namespace GodotTools.IdeMessaging
+{
+    public class MessageDecoder
+    {
+        private class DecodedMessage
+        {
+            public MessageKind? Kind;
+            public string? Id;
+            public MessageStatus? Status;
+            public readonly StringBuilder Body = new StringBuilder();
+            public uint? PendingBodyLines;
+
+            public void Clear()
+            {
+                Kind = null;
+                Id = null;
+                Status = null;
+                Body.Clear();
+                PendingBodyLines = null;
+            }
+
+            public Message ToMessage()
+            {
+                if (!Kind.HasValue || Id == null || !Status.HasValue ||
+                    !PendingBodyLines.HasValue || PendingBodyLines.Value > 0)
+                    throw new InvalidOperationException();
+
+                return new Message(Kind.Value, Id, new MessageContent(Status.Value, Body.ToString()));
+            }
+        }
+
+        public enum State
+        {
+            Decoding,
+            Decoded,
+            Errored
+        }
+
+        private readonly DecodedMessage decodingMessage = new DecodedMessage();
+
+        public State Decode(string messageLine, out Message? decodedMessage)
+        {
+            decodedMessage = null;
+
+            if (!decodingMessage.Kind.HasValue)
+            {
+                if (!Enum.TryParse(messageLine, ignoreCase: true, out MessageKind kind))
+                {
+                    decodingMessage.Clear();
+                    return State.Errored;
+                }
+
+                decodingMessage.Kind = kind;
+            }
+            else if (decodingMessage.Id == null)
+            {
+                decodingMessage.Id = messageLine;
+            }
+            else if (decodingMessage.Status == null)
+            {
+                if (!Enum.TryParse(messageLine, ignoreCase: true, out MessageStatus status))
+                {
+                    decodingMessage.Clear();
+                    return State.Errored;
+                }
+
+                decodingMessage.Status = status;
+            }
+            else if (decodingMessage.PendingBodyLines == null)
+            {
+                if (!uint.TryParse(messageLine, out uint pendingBodyLines))
+                {
+                    decodingMessage.Clear();
+                    return State.Errored;
+                }
+
+                decodingMessage.PendingBodyLines = pendingBodyLines;
+            }
+            else
+            {
+                if (decodingMessage.PendingBodyLines > 0)
+                {
+                    decodingMessage.Body.AppendLine(messageLine);
+                    decodingMessage.PendingBodyLines -= 1;
+                }
+                else
+                {
+                    decodedMessage = decodingMessage.ToMessage();
+                    decodingMessage.Clear();
+                    return State.Decoded;
+                }
+            }
+
+            return State.Decoding;
+        }
+    }
+}