WIP: refactor to parse incoming stream as state machine

1 files changed, 181 insertions, 0 deletions

diff --git a/src/jid.rs b/src/jid.rs
new file mode 100644
index 0000000..65738dc
--- /dev/null
+++ b/src/jid.rs
@@ -0,0 +1,181 @@
+use std::str::FromStr;
+
+use serde::Serialize;
+
+#[derive(PartialEq, Debug, Clone)]
+pub struct JID {
+    // TODO: validate localpart (length, char]
+    pub localpart: Option<String>,
+    pub domainpart: String,
+    pub resourcepart: Option<String>,
+}
+
+impl Serialize for JID {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(&self.to_string())
+    }
+}
+
+pub enum JIDError {
+    NoResourcePart,
+    ParseError(ParseError),
+}
+
+#[derive(Debug)]
+pub enum ParseError {
+    Empty,
+    Malformed,
+}
+
+impl JID {
+    pub fn new(
+        localpart: Option<String>,
+        domainpart: String,
+        resourcepart: Option<String>,
+    ) -> Self {
+        Self {
+            localpart,
+            domainpart: domainpart.parse().unwrap(),
+            resourcepart,
+        }
+    }
+
+    pub fn as_bare(&self) -> Self {
+        Self {
+            localpart: self.localpart.clone(),
+            domainpart: self.domainpart.clone(),
+            resourcepart: None,
+        }
+    }
+
+    pub fn as_full(&self) -> Result<&Self, JIDError> {
+        if let Some(_) = self.resourcepart {
+            Ok(&self)
+        } else {
+            Err(JIDError::NoResourcePart)
+        }
+    }
+}
+
+impl FromStr for JID {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let split: Vec<&str> = s.split('@').collect();
+        match split.len() {
+            0 => Err(ParseError::Empty),
+            1 => {
+                let split: Vec<&str> = split[0].split('/').collect();
+                match split.len() {
+                    1 => Ok(JID::new(None, split[0].to_string(), None)),
+                    2 => Ok(JID::new(
+                        None,
+                        split[0].to_string(),
+                        Some(split[1].to_string()),
+                    )),
+                    _ => Err(ParseError::Malformed),
+                }
+            }
+            2 => {
+                let split2: Vec<&str> = split[1].split('/').collect();
+                match split2.len() {
+                    1 => Ok(JID::new(
+                        Some(split[0].to_string()),
+                        split2[0].to_string(),
+                        None,
+                    )),
+                    2 => Ok(JID::new(
+                        Some(split[0].to_string()),
+                        split2[0].to_string(),
+                        Some(split2[1].to_string()),
+                    )),
+                    _ => Err(ParseError::Malformed),
+                }
+            }
+            _ => Err(ParseError::Malformed),
+        }
+    }
+}
+
+impl TryFrom<String> for JID {
+    type Error = ParseError;
+
+    fn try_from(value: String) -> Result<Self, Self::Error> {
+        value.parse()
+    }
+}
+
+impl TryFrom<&str> for JID {
+    type Error = ParseError;
+
+    fn try_from(value: &str) -> Result<Self, Self::Error> {
+        value.parse()
+    }
+}
+
+impl std::fmt::Display for JID {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "{}{}{}",
+            self.localpart.clone().map(|l| l + "@").unwrap_or_default(),
+            self.domainpart,
+            self.resourcepart
+                .clone()
+                .map(|r| "/".to_owned() + &r)
+                .unwrap_or_default()
+        )
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn jid_to_string() {
+        assert_eq!(
+            JID::new(Some("cel".into()), "blos.sm".into(), None).to_string(),
+            "cel@blos.sm".to_owned()
+        );
+    }
+
+    #[test]
+    fn parse_full_jid() {
+        assert_eq!(
+            "cel@blos.sm/greenhouse".parse::<JID>().unwrap(),
+            JID::new(
+                Some("cel".into()),
+                "blos.sm".into(),
+                Some("greenhouse".into())
+            )
+        )
+    }
+
+    #[test]
+    fn parse_bare_jid() {
+        assert_eq!(
+            "cel@blos.sm".parse::<JID>().unwrap(),
+            JID::new(Some("cel".into()), "blos.sm".into(), None)
+        )
+    }
+
+    #[test]
+    fn parse_domain_jid() {
+        assert_eq!(
+            "component.blos.sm".parse::<JID>().unwrap(),
+            JID::new(None, "component.blos.sm".into(), None)
+        )
+    }
+
+    #[test]
+    fn parse_full_domain_jid() {
+        assert_eq!(
+            "component.blos.sm/bot".parse::<JID>().unwrap(),
+            JID::new(None, "component.blos.sm".into(), Some("bot".into()))
+        )
+    }
+}