Move namespace to dedicated dav crate

crates/dav/src/lib.rs

@@ -0,0 +1 @@
+pub mod namespace;

crates/dav/src/namespace.rs

@@ -0,0 +1,44 @@
+use quick_xml::events::attributes::Attribute;
+
+// An enum keeping track of the XML namespaces used for WebDAV and its extensions
+//
+// Can also generate appropriate attributes for quick_xml
+pub enum Namespace {
+    Dav,
+    CalDAV,
+    CardDAV,
+    ICal,
+    CServer,
+    Nextcloud,
+}
+
+impl Namespace {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Self::Dav => "DAV:",
+            Self::CalDAV => "urn:ietf:params:xml:ns:caldav",
+            Self::CardDAV => "urn:ietf:params:xml:ns:carddav",
+            Self::ICal => "http://apple.com/ns/ical/",
+            Self::CServer => "http://calendarserver.org/ns/",
+            Self::Nextcloud => "http://nextcloud.com/ns",
+        }
+    }
+
+    // Returns an opinionated namespace attribute name
+    pub fn xml_attr(&self) -> &'static str {
+        match self {
+            Self::Dav => "xmlns",
+            Self::CalDAV => "xmlns:C",
+            Self::CardDAV => "xmlns:CARD",
+            Self::ICal => "xmlns:IC",
+            Self::CServer => "xmlns:CS",
+            Self::Nextcloud => "xmlns:NEXTC",
+        }
+    }
+}
+
+impl From<Namespace> for Attribute<'static> {
+    fn from(value: Namespace) -> Self {
+        (value.xml_attr(), value.as_str()).into()
+    }
+}