Add a MessagePayload trait, and implement it for Body and ChatState.

src/lib.rs

@@ -12,3 +12,18 @@ pub mod jingle;
 pub mod ping;
 pub mod chatstates;
 pub mod ibb;
+
+use std::fmt::Debug;
+use minidom::Element;
+
+pub trait MessagePayload: Debug {}
+
+pub fn parse_message_payload(elem: &Element) -> Option<Box<MessagePayload>> {
+    if let Ok(body) = body::parse_body(elem) {
+        Some(Box::new(body))
+    } else if let Ok(chatstate) = chatstates::parse_chatstate(elem) {
+        Some(Box::new(chatstate))
+    } else {
+        None
+    }
+}