Fix ChatMessageRole to be singletons, pull ChatMessage to seperate file

OpenAI_API/Chat/ChatMessage.cs

@@ -0,0 +1,57 @@
+using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace OpenAI_API.Chat
+{
+	/// <summary>
+	/// Chat message sent or received from the API. Includes who is speaking in the "role" and the message text in the "content"
+	/// </summary>
+	public class ChatMessage
+	{
+		/// <summary>
+		/// Creates an empty <see cref="ChatMessage"/>, with <see cref="Role"/> defaulting to <see cref="ChatMessageRole.User"/>
+		/// </summary>
+		public ChatMessage()
+		{
+			this.Role = ChatMessageRole.User;
+		}
+
+		/// <summary>
+		/// Constructor for a new Chat Message
+		/// </summary>
+		/// <param name="role">The role of the message, which can be "system", "assistant" or "user"</param>
+		/// <param name="content">The text to send in the message</param>
+		public ChatMessage(ChatMessageRole role, string content)
+		{
+			this.Role = role;
+			this.Content = content;
+		}
+
+		[JsonProperty("role")]
+		internal string rawRole { get; set; }
+
+		/// <summary>
+		/// The role of the message, which can be "system", "assistant" or "user"
+		/// </summary>
+		[JsonIgnore]
+		public ChatMessageRole Role
+		{
+			get
+			{
+				return ChatMessageRole.FromString(rawRole);
+			}
+			set
+			{
+				rawRole = value.ToString();
+			}
+		}
+
+		/// <summary>
+		/// The content of the message
+		/// </summary>
+		[JsonProperty("content")]
+		public string Content { get; set; }
+	}
+}

OpenAI_API/Chat/ChatMessageRole.cs

@@ -12,7 +12,7 @@ namespace OpenAI_API.Chat
 	public class ChatMessageRole : IEquatable<ChatMessageRole>
 	{
 		/// <summary>
-		/// Contructor is prvate to force usage of strongly typed values
+		/// Contructor is private to force usage of strongly typed values
 		/// </summary>
 		/// <param name="value"></param>
 		private ChatMessageRole(string value) { Value = value; }
@@ -37,20 +37,20 @@ public static ChatMessageRole FromString(string roleName)
 			}
 		}
 
-		private string Value { get; set; }
+		private string Value { get; }
 
 		/// <summary>
 		/// The system message helps set the behavior of the assistant. 
 		/// </summary>
-		public static ChatMessageRole System { get { return new ChatMessageRole("system"); } }
+		public static ChatMessageRole System { get; } = new ChatMessageRole("system");
 		/// <summary>
 		/// The user messages help instruct the assistant. They can be generated by the end users of an application, or set by a developer as an instruction.
 		/// </summary>
-		public static ChatMessageRole User { get { return new ChatMessageRole("user"); } }
+		public static ChatMessageRole User { get; } = new ChatMessageRole("user");
 		/// <summary>
 		/// The assistant messages help store prior responses. They can also be written by a developer to help give examples of desired behavior.
 		/// </summary>
-		public static ChatMessageRole Assistant { get { return new ChatMessageRole("assistant"); } }
+		public static ChatMessageRole Assistant { get; } = new ChatMessageRole("assistant");
 
 		/// <summary>
 		/// Gets the string value for this role to pass to the API

OpenAI_API/Chat/ChatResult.cs

@@ -81,50 +81,6 @@ public override string ToString()
 		}
 	}
 
-	/// <summary>
-	/// Chat message sent or received from the API. Includes who is speaking in the "role" and the message text in the "content"
-	/// </summary>
-	public class ChatMessage
-	{
-		public ChatMessage() { }
-
-		/// <summary>
-		/// Constructor for a new Chat Message
-		/// </summary>
-		/// <param name="role">The role of the message, which can be "system", "assistant" or "user"</param>
-		/// <param name="content">The text to send in the message</param>
-		public ChatMessage(ChatMessageRole role, string content)
-		{
-			this.Role = role;
-			this.Content = content;
-		}
-
-		[JsonProperty("role")]
-		internal string rawRole { get; set; }
-
-		/// <summary>
-		/// The role of the message, which can be "system", "assistant" or "user"
-		/// </summary>
-		[JsonIgnore]
-		public ChatMessageRole Role
-		{
-			get
-			{
-				return ChatMessageRole.FromString(rawRole);
-			}
-			set
-			{
-				rawRole = value.ToString();
-			}
-		}
-
-		/// <summary>
-		/// The content of the message
-		/// </summary>
-		[JsonProperty("content")]
-		public string Content { get; set; }
-	}
-
 	/// <summary>
 	/// How many tokens were used in this chat message.
 	/// </summary>

OpenAI_Tests/ChatEndpointTests.cs

@@ -79,6 +79,7 @@ public void SimpleCompletion()
 			Assert.NotZero(results.Choices.Count);
 			Assert.AreEqual(ChatMessageRole.Assistant, results.Choices[0].Message.Role);
 			Assert.That(results.Choices.All(c => c.Message.Role.Equals(ChatMessageRole.Assistant)));
+			Assert.That(results.Choices.All(c => c.Message.Role == ChatMessageRole.Assistant));
 			Assert.That(results.Choices.All(c => c.Message.Content.Length > 1));
 			Assert.IsNotEmpty(results.ToString());
 		}