WIP: refactor Element type

2 files changed, 226 insertions, 134 deletions

diff --git a/src/error.rs b/src/error.rs
index a912840..8aa98ae 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -25,6 +25,7 @@ pub enum JabberError {
     ParseError,
     UnexpectedEnd,
     UnexpectedElement,
+    UnexpectedText,
     XML(quick_xml::Error),
     SASL(SASLError),
     Element(ElementError<'static>),
diff --git a/src/stanza/mod.rs b/src/stanza/mod.rs
index 8251422..7f4790d 100644
--- a/src/stanza/mod.rs
+++ b/src/stanza/mod.rs
@@ -6,14 +6,15 @@ pub mod sasl;
 pub mod stream;
 
 use std::collections::BTreeMap;
+use std::str;
 
 // const DECLARATION: BytesDecl<'_> = BytesDecl::new("1.0", None, None);
 use async_recursion::async_recursion;
-use quick_xml::events::{BytesStart, Event};
+use quick_xml::events::{BytesEnd, BytesStart, BytesText, Event};
 use quick_xml::{Reader, Writer};
 use tokio::io::{AsyncBufRead, AsyncWrite};
 
-use crate::JabberError;
+use crate::{JabberError, Result};
 
 // #[derive(Clone, Debug)]
 // pub struct EventTree<'e> {
@@ -29,6 +30,9 @@ pub struct Element<'s> {
     /// element prefix
     /// e.g. `foo` in `<foo:bar />`.
     prefix: Option<&'s str>,
+    /// element name
+    /// e.g. `bar` in `<foo:bar />`.
+    localname: &'s str,
     /// qualifying namespace
     /// an element must be qualified by a namespace
     /// e.g. for `<stream:features>` in
@@ -57,9 +61,6 @@ pub struct Element<'s> {
     /// ```
     /// would be `"jabber:client"`
     namespace: &'s str,
-    /// element name
-    /// e.g. `bar` in `<foo:bar />`.
-    name: &'s str,
     /// all namespaces applied to element
     /// e.g. for `<bind>` in
     /// ```
@@ -73,12 +74,11 @@ pub struct Element<'s> {
     /// ```
     /// would be `[(None, "urn:ietf:params:xml:ns:xmpp-bind")]` despite
     /// `(Some("stream"), "http://etherx.jabber.org/streams")` also being available
-    namespaces: Box<BTreeMap<Option<&'s str>, &'s str>>,
+    namespace_declarations: Box<BTreeMap<Option<&'s str>, &'s str>>,
     /// element attributes
     attributes: Box<BTreeMap<&'s str, &'s str>>,
     // children elements namespaces contain their parents' namespaces
-    ///
-    children: Option<Box<Vec<Node<'s>>>>,
+    children: Box<Vec<Node<'s>>>,
 }
 
 #[derive(Clone, Debug)]
@@ -87,190 +87,281 @@ pub enum Node<'s> {
     Text(&'s str),
 }
 
-impl<'s> From<&Element<'s>> for Event<'s> {
-    fn from(element: &Element<'s>) -> Self {
-        let event;
-        if let Some(prefix) = element.prefix {
-            event = BytesStart::new(format!("{}:{}", prefix, element.name));
+impl<'s> From<&Node<'s>> for Vec<Event<'s>> {
+    fn from(node: &Node<'s>) -> Self {
+        match node {
+            Node::Element(e) => e.into(),
+            Node::Text(t) => vec![Event::Text(BytesText::new(t))],
+        }
+    }
+}
+
+impl<'s> Element<'s> {
+    /// returns the fully qualified name
+    /// e.g. `foo:bar` in
+    /// `<foo:bar>`.
+    pub fn name(&self) -> &str {
+        if let Some(prefix) = self.prefix {
+            format!("{}:{}", prefix, self.localname).as_str()
         } else {
-            event = BytesStart::new(element.name);
+            self.localname
         }
+    }
 
-        event
-        
-        let event = event.with_attributes(element.attributes.into_iter());
+    /// returns the localname.
+    /// e.g. `bar` in `<foo:bar>`
+    pub fn localname(&self) -> &str {
+        self.localname
+    }
 
-        match element.children.is_none() {
-            true => return Event::Empty(event),
-            false => return Event::Start(event),
-        }
+    /// returns the prefix.
+    /// e.g. `foo` in `<foo:bar>`. returns None if there is
+    /// no prefix.
+    pub fn prefix(&self) -> Option<&str> {
+        self.prefix
     }
-}
 
-impl<'s> Element<'s> {
     /// returns the namespace which applies to the current element, e.g. for
-    /// `<stream:stream xmlns='jabber:client' xmlns:stream='http://etherx.jabber.org/streams'>`
-    /// it will be `http://etherx.jabber.org/streams` but for
-    /// `<stream xmlns='jabber:client' xmlns:stream='http://etherx.jabber.org/streams'>`
-    /// it will be `jabber:client`.
-    pub fn get_namespace(&self) -> &str {
+    /// `<element xmlns='foo' xmlns:bar='bar'>`
+    /// it will be `foo` but for
+    /// `<bar:element xmlns='foo' xmlns:bar='bar'>`
+    /// it will be `bar`.
+    pub fn namespace(&self) -> &str {
         self.namespace
     }
 }
 
-impl<'e: 'async_recursion, 'async_recursion> Element<'e> {
-    pub fn write<'life0, W: AsyncWrite + Unpin + Send>(
-        &'async_recursion self,
-        writer: &'life0 mut Writer<W>,
-    ) -> ::core::pin::Pin<
-        Box<
-            dyn ::core::future::Future<Output = Result<(), JabberError>>
-                + 'async_recursion
-                + ::core::marker::Send,
-        >,
-    >
-    where
-        W: 'async_recursion,
-        'life0: 'async_recursion,
-    {
-        Box::pin(async move {
-            match &self.children.is_empty() {
-                true => {}
+impl<'s> From<&Element<'s>> for Vec<Event<'s>> {
+    fn from(element: &Element<'s>) -> Self {
+        let name = element.name();
+
+        let event = BytesStart::new(name);
+
+        // namespace declarations
+        let namespace_declarations = element.namespace_declarations.iter().map(|declaration| {
+            let (prefix, namespace) = declaration;
+            match prefix {
+                Some(prefix) => return (format!("xmlns:{}", prefix).as_str(), *namespace),
+                None => return ("xmlns", *namespace),
             }
-            match &self.event {
-                Event::Start(e) => {
-                    writer.write_event_async(Event::Start(e.clone())).await?;
-                    if let Some(children) = &self.children {
-                        for e in children {
-                            e.write(writer).await?;
-                        }
-                    }
-                    writer.write_event_async(Event::End(e.to_end())).await?;
-                    return Ok(());
+        });
+        let event = event.with_attributes(namespace_declarations);
+
+        // attributes
+        let event = event.with_attributes(element.attributes.into_iter());
+
+        match element.children.is_empty() {
+            true => return vec![Event::Empty(event)],
+            false => {
+                return {
+                    let start: Vec<Event<'s>> = vec![Event::Start(event)];
+                    let start_and_content: Vec<Event<'s>> = start
+                        .into_iter()
+                        .chain({
+                            let u = element.children.iter().fold(
+                                Vec::new(),
+                                |acc: Vec<Event<'s>>, child: &Node<'s>| {
+                                    acc.into_iter()
+                                        .chain(Into::<Vec<Event<'s>>>::into(child).into_iter())
+                                        .collect()
+                                },
+                            );
+                            u
+                        })
+                        .collect();
+                    let full: Vec<Event<'s>> = start_and_content
+                        .into_iter()
+                        .chain(vec![Event::End(BytesEnd::new(name))])
+                        .collect();
+                    full
                 }
-                e => Ok(writer.write_event_async(e).await?),
             }
-        })
+        }
     }
 }
 
-impl<'e> Element<'e> {
+impl<'s> Element<'s> {
+    /// if there is only one child in the vec of children, will return that element
+    pub fn child(&self) -> Result<&Element<'s>> {
+        if self.children.len() == 1 {
+            Ok(&self.children[0])
+        } else {
+            Err(ElementError::NoChildren.into())
+        }
+    }
+
+    /// returns reference to children
+    pub fn children(&self) -> Result<&Vec<Element<'s>>> {
+        if !self.children.is_empty() {
+            Ok(&self.children)
+        } else {
+            Err(ElementError::NoChildren.into())
+        }
+    }
+
+    /// returns text content, error if there is none
+    pub fn content(&self) -> Result<&str> {
+        for node in *self.children {
+            match node {
+                Node::Text(t) => return Ok(t),
+                _ => {}
+            }
+        }
+        Err(ElementError::NotText)
+    }
+
+    pub async fn write<W: AsyncWrite + Unpin + Send>(&self, writer: &mut Writer<W>) -> Result<()> {
+        let events: Vec<Event> = self.into();
+        for event in events {
+            writer.write_event_async(event).await?
+        }
+        Ok(())
+    }
+
     pub async fn write_start<W: AsyncWrite + Unpin + Send>(
         &self,
         writer: &mut Writer<W>,
-    ) -> Result<(), JabberError> {
-        match self.event.as_ref() {
-            Event::Start(e) => Ok(writer.write_event_async(Event::Start(e.clone())).await?),
-            e => Err(ElementError::NotAStart(e.clone().into_owned()).into()),
-        }
+    ) -> Result<()> {
+        let mut event = BytesStart::new(self.name());
+
+        // namespace declarations
+        self.namespace_declarations.iter().for_each(|declaration| {
+            let (prefix, namespace) = declaration;
+            match prefix {
+                Some(prefix) => {
+                    event.push_attribute((format!("xmlns:{}", prefix).as_str(), *namespace))
+                }
+                None => event.push_attribute(("xmlns", *namespace)),
+            }
+        });
+
+        // attributes
+        let event =
+            event.with_attributes(self.attributes.iter().map(|(attr, value)| (*attr, *value)));
+
+        writer.write_event_async(Event::Start(event)).await?;
+
+        Ok(())
     }
 
     pub async fn write_end<W: AsyncWrite + Unpin + Send>(
         &self,
         writer: &mut Writer<W>,
-    ) -> Result<(), JabberError> {
-        match self.event.as_ref() {
-            Event::Start(e) => Ok(writer
-                .write_event_async(Event::End(e.clone().to_end()))
-                .await?),
-            e => Err(ElementError::NotAStart(e.clone().into_owned()).into()),
-        }
+    ) -> Result<()> {
+        let event = BytesEnd::new(self.name());
+        writer.write_event_async(Event::End(event)).await?;
+        Ok(())
     }
+    //     pub async fn write_start<W: AsyncWrite + Unpin + Send>(
+    //         &self,
+    //         writer: &mut Writer<W>,
+    //     ) -> Result<(), JabberError> {
+    //         match self.event.as_ref() {
+    //             Event::Start(e) => Ok(writer.write_event_async(Event::Start(e.clone())).await?),
+    //             e => Err(ElementError::NotAStart(e.clone().into_owned()).into()),
+    //         }
+    //     }
+
+    //     pub async fn write_end<W: AsyncWrite + Unpin + Send>(
+    //         &self,
+    //         writer: &mut Writer<W>,
+    //     ) -> Result<(), JabberError> {
+    //         match self.event.as_ref() {
+    //             Event::Start(e) => Ok(writer
+    //                 .write_event_async(Event::End(e.clone().to_end()))
+    //                 .await?),
+    //             e => Err(ElementError::NotAStart(e.clone().into_owned()).into()),
+    //         }
+    //     }
 
     #[async_recursion]
     pub async fn read<R: AsyncBufRead + Unpin + Send>(
         reader: &mut Reader<R>,
-    ) -> Result<Self, JabberError> {
-        let element = Self::read_recursive(reader)
+        local_namespaces: BTreeMap<Option<&str>, &str>,
+    ) -> Result<Self> {
+        let node = Node::read_recursive(reader, local_namespaces)
             .await?
-            .ok_or(JabberError::UnexpectedEnd);
-        element
+            .ok_or(JabberError::UnexpectedEnd)?;
+        match node {
+            Node::Element(e) => Ok(e),
+            Node::Text(_) => Err(JabberError::UnexpectedText),
+        }
     }
+}
 
+impl<'s> Node<'s> {
     #[async_recursion]
     async fn read_recursive<R: AsyncBufRead + Unpin + Send>(
         reader: &mut Reader<R>,
-    ) -> Result<Option<Self>, JabberError> {
+        local_namespaces: BTreeMap<Option<&str>, &str>,
+    ) -> Result<Option<Node<'s>>> {
         let mut buf = Vec::new();
         let event = reader.read_event_into_async(&mut buf).await?;
         match event {
             Event::Start(e) => {
-                let mut children_vec = Vec::new();
+                let prefix = e
+                    .name()
+                    .prefix()
+                    .map(|prefix| str::from_utf8(prefix.into_inner())?);
+
+                let mut children_vec: Vec = Vec::new();
                 while let Some(sub_element) = Element::read_recursive(reader).await? {
                     children_vec.push(sub_element)
                 }
-                let mut children = None;
-                if !children_vec.is_empty() {
-                    children = Some(children_vec)
-                }
-                Ok(Some(Self {
-                    event: Event::Start(e.into_owned()),
-                    children,
-                }))
+                Ok(Some(Self::Element(Element {
+                    prefix,
+                    localname: e.local_name().into_inner(),
+                    namespace: todo!(),
+                    namespace_declarations: todo!(),
+                    attributes: todo!(),
+                    children: todo!(),
+                })))
             }
             Event::End(_) => Ok(None),
+            Event::Text(e) => Ok(Some(Self::Text(e.unescape()?.as_ref()))),
             e => Ok(Some(Self {
                 event: e.into_owned(),
                 children: None,
             })),
         }
     }
-
-    #[async_recursion]
-    pub async fn read_start<R: AsyncBufRead + Unpin + Send>(
-        reader: &mut Reader<R>,
-    ) -> Result<Self, JabberError> {
-        let mut buf = Vec::new();
-        let event = reader.read_event_into_async(&mut buf).await?;
-        match event {
-            Event::Start(e) => {
-                return Ok(Self {
-                    event: Event::Start(e.into_owned()),
-                    children: None,
-                })
-            }
-            e => Err(ElementError::NotAStart(e.into_owned()).into()),
-        }
-    }
-
-    /// if there is only one child in the vec of children, will return that element
-    pub fn child<'p>(&'p self) -> Result<&'p Element<'e>, ElementError<'static>> {
-        if let Some(children) = &self.children {
-            if children.len() == 1 {
-                return Ok(&children[0]);
-            } else {
-                return Err(ElementError::MultipleChildren);
-            }
-        }
-        Err(ElementError::NoChildren)
-    }
-
-    /// returns reference to children
-    pub fn children<'p>(&'p self) -> Result<&'p Vec<Element<'e>>, ElementError<'e>> {
-        if let Some(children) = &self.children {
-            return Ok(children);
-        }
-        Err(ElementError::NoChildren)
-    }
 }
 
-pub trait IntoElement<'e> {
-    fn event(&self) -> Event<'e>;
-    fn children(&self) -> Option<Vec<Element<'e>>>;
-}
+// #[async_recursion]
+// pub async fn read_start<R: AsyncBufRead + Unpin + Send>(
+//     reader: &mut Reader<R>,
+// ) -> Result<Self, JabberError> {
+//     let mut buf = Vec::new();
+//     let event = reader.read_event_into_async(&mut buf).await?;
+//     match event {
+//         Event::Start(e) => {
+//             return Ok(Self {
+//                 event: Event::Start(e.into_owned()),
+//                 children: None,
+//             })
+//         }
+//         e => Err(ElementError::NotAStart(e.into_owned()).into()),
+//     }
+// }
 
-impl<'e, T: IntoElement<'e>> From<T> for Element<'e> {
-    fn from(value: T) -> Self {
-        Element {
-            event: value.event(),
-            children: value.children(),
-        }
-    }
-}
+// pub trait IntoElement<'e> {
+//     fn event(&self) -> Event<'e>;
+//     fn children(&self) -> Option<Vec<Element<'e>>>;
+// }
+
+// impl<'e, T: IntoElement<'e>> From<T> for Element<'e> {
+//     fn from(value: T) -> Self {
+//         Element {
+//             event: value.event(),
+//             children: value.children(),
+//         }
+//     }
+// }
 
 #[derive(Debug)]
 pub enum ElementError<'e> {
     NotAStart(Event<'e>),
+    NotText,
     NoChildren,
     MultipleChildren,
 }