update comments

bot/msg/events.go

@@ -2,8 +2,28 @@ package msg
 
 import "github.com/Tnze/go-mc/chat"
 
+// EventsHandler is a collection of event handlers.
+// Fill the fields with your handler functions and pass this struct to [New] to create the msg manager.
+// The handler functions will be called when the corresponding event is triggered.
+// Leave the fields as nil if you don't want to handle the event.
 type EventsHandler struct {
-	SystemChat        func(msg chat.Message, overlay bool) error
+	// SystemChat handles messages sent by gaming system.
+	//
+	// In vanilla client:
+	// If overlay is false, the message will be displayed in the chat box.
+	// If overlay is true, the message will be displayed on the top of the hot-bar.
+	SystemChat func(msg chat.Message, overlay bool) error
+
+	// PlayerChatMessage handles messages sent by players.
+	//
+	// Message signing system is added in 1.19. The message and its context could be signed by the player's private key.
+	// The manager tries to verify the message signature through the player's public key,
+	// and return the result as validated boolean.
 	PlayerChatMessage func(msg chat.Message, validated bool) error
-	DisguisedChat     func(msg chat.Message) error
+
+	// DisguisedChat handles DisguisedChat message.
+	//
+	// DisguisedChat message used to send system chat.
+	// Now it is used to send messages from "/say" command from server console.
+	DisguisedChat func(msg chat.Message) error
 }