From 8b964df645a856d25a07d808b24ddf78938b8bc8 Mon Sep 17 00:00:00 2001
From: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Date: Sat, 29 Apr 2017 03:23:50 +0100
Subject: [PATCH] Add a stanza-id parser and serialiser.

---
 src/lib.rs       |   3 ++
 src/ns.rs        |   3 ++
 src/stanza_id.rs | 129 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 135 insertions(+)
 create mode 100644 src/stanza_id.rs

diff --git a/src/lib.rs b/src/lib.rs
index 19689510..e2a656b3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -74,6 +74,9 @@ pub mod hashes;
 /// XEP-0308: Last Message Correction
 pub mod message_correct;
 
+/// XEP-0359: Unique and Stable Stanza IDs
+pub mod stanza_id;
+
 /// XEP-0380: Explicit Message Encryption
 pub mod eme;
 
diff --git a/src/ns.rs b/src/ns.rs
index 415858c9..a3484637 100644
--- a/src/ns.rs
+++ b/src/ns.rs
@@ -57,6 +57,9 @@ pub const HASH_ALGO_BLAKE2B_512: &'static str = "urn:xmpp:hash-function-text-nam
 /// XEP-0308: Last Message Correction
 pub const MESSAGE_CORRECT: &'static str = "urn:xmpp:message-correct:0";
 
+/// XEP-0359: Unique and Stable Stanza IDs
+pub const SID: &'static str = "urn:xmpp:sid:0";
+
 /// XEP-0380: Explicit Message Encryption
 pub const EME: &'static str = "urn:xmpp:eme:0";
 
diff --git a/src/stanza_id.rs b/src/stanza_id.rs
new file mode 100644
index 00000000..14d842b7
--- /dev/null
+++ b/src/stanza_id.rs
@@ -0,0 +1,129 @@
+use minidom::Element;
+use jid::Jid;
+
+use error::Error;
+
+use ns;
+
+#[derive(Debug, Clone)]
+pub enum StanzaId {
+    StanzaId {
+        id: String,
+        by: Jid,
+    },
+    OriginId {
+        id: String,
+    },
+}
+
+pub fn parse_stanza_id(root: &Element) -> Result<StanzaId, Error> {
+    let is_stanza_id = root.is("stanza-id", ns::SID);
+    if !is_stanza_id && !root.is("origin-id", ns::SID) {
+        return Err(Error::ParseError("This is not a stanza-id or origin-id element."));
+    }
+    for _ in root.children() {
+        return Err(Error::ParseError("Unknown child in stanza-id or origin-id element."));
+    }
+    let id = match root.attr("id") {
+        Some(id) => id.to_owned(),
+        None => return Err(Error::ParseError("No 'id' attribute present in stanza-id or origin-id.")),
+    };
+    Ok(if is_stanza_id {
+        let by = match root.attr("by") {
+            Some(by) => by.parse().unwrap(),
+            None => return Err(Error::ParseError("No 'by' attribute present in stanza-id.")),
+        };
+        StanzaId::StanzaId { id, by }
+    } else {
+        StanzaId::OriginId { id }
+    })
+}
+
+pub fn serialise(stanza_id: &StanzaId) -> Element {
+    match *stanza_id {
+        StanzaId::StanzaId { ref id, ref by } => {
+            Element::builder("stanza-id")
+                    .ns(ns::SID)
+                    .attr("id", id.clone())
+                    .attr("by", String::from(by.clone()))
+                    .build()
+        },
+        StanzaId::OriginId { ref id } => {
+            Element::builder("origin-id")
+                    .ns(ns::SID)
+                    .attr("id", id.clone())
+                    .build()
+        },
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::str::FromStr;
+
+    use minidom::Element;
+    use jid::Jid;
+    use error::Error;
+    use stanza_id;
+
+    #[test]
+    fn test_simple() {
+        let elem: Element = "<stanza-id xmlns='urn:xmpp:sid:0' id='coucou' by='coucou@coucou'/>".parse().unwrap();
+        let stanza_id = stanza_id::parse_stanza_id(&elem).unwrap();
+        if let stanza_id::StanzaId::StanzaId { id, by } = stanza_id {
+            assert_eq!(id, String::from("coucou"));
+            assert_eq!(by, Jid::from_str("coucou@coucou").unwrap());
+        } else {
+            panic!();
+        }
+
+        let elem: Element = "<origin-id xmlns='urn:xmpp:sid:0' id='coucou'/>".parse().unwrap();
+        let stanza_id = stanza_id::parse_stanza_id(&elem).unwrap();
+        if let stanza_id::StanzaId::OriginId { id } = stanza_id {
+            assert_eq!(id, String::from("coucou"));
+        } else {
+            panic!();
+        }
+    }
+
+    #[test]
+    fn test_invalid_child() {
+        let elem: Element = "<stanza-id xmlns='urn:xmpp:sid:0'><coucou/></stanza-id>".parse().unwrap();
+        let error = stanza_id::parse_stanza_id(&elem).unwrap_err();
+        let message = match error {
+            Error::ParseError(string) => string,
+            _ => panic!(),
+        };
+        assert_eq!(message, "Unknown child in stanza-id or origin-id element.");
+    }
+
+    #[test]
+    fn test_invalid_id() {
+        let elem: Element = "<stanza-id xmlns='urn:xmpp:sid:0'/>".parse().unwrap();
+        let error = stanza_id::parse_stanza_id(&elem).unwrap_err();
+        let message = match error {
+            Error::ParseError(string) => string,
+            _ => panic!(),
+        };
+        assert_eq!(message, "No 'id' attribute present in stanza-id or origin-id.");
+    }
+
+    #[test]
+    fn test_invalid_by() {
+        let elem: Element = "<stanza-id xmlns='urn:xmpp:sid:0' id='coucou'/>".parse().unwrap();
+        let error = stanza_id::parse_stanza_id(&elem).unwrap_err();
+        let message = match error {
+            Error::ParseError(string) => string,
+            _ => panic!(),
+        };
+        assert_eq!(message, "No 'by' attribute present in stanza-id.");
+    }
+
+    #[test]
+    fn test_serialise() {
+        let elem: Element = "<stanza-id xmlns='urn:xmpp:sid:0' id='coucou' by='coucou@coucou'/>".parse().unwrap();
+        let stanza_id = stanza_id::StanzaId::StanzaId { id: String::from("coucou"), by: Jid::from_str("coucou@coucou").unwrap() };
+        let elem2 = stanza_id::serialise(&stanza_id);
+        assert_eq!(elem, elem2);
+    }
+}