Started working on contact resolution

kordophoned/src/daemon/contact_resolver/mod.rs

@@ -0,0 +1,46 @@
+pub mod eds;
+pub use eds::EDSContactResolverBackend;
+
+pub trait ContactResolverBackend {
+    type ContactID;
+
+    fn resolve_contact_id(&self, address: &str) -> Option<Self::ContactID>;
+    fn get_contact_display_name(&self, contact_id: &Self::ContactID) -> Option<String>;
+}
+
+pub type AnyContactID = String;
+
+pub struct ContactResolver<T: ContactResolverBackend> {
+    backend: T,
+}
+
+impl<T: ContactResolverBackend> ContactResolver<T>
+where
+    T::ContactID: From<AnyContactID>,
+    T::ContactID: Into<AnyContactID>,
+    T: Default,
+{
+    pub fn new(backend: T) -> Self {
+        Self { backend }
+    }
+
+    pub fn resolve_contact_id(&self, address: &str) -> Option<AnyContactID> {
+        self.backend.resolve_contact_id(address).map(|id| id.into())
+    }
+
+    pub fn get_contact_display_name(&self, contact_id: &AnyContactID) -> Option<String> {
+        let backend_contact_id: T::ContactID = T::ContactID::from((*contact_id).clone());
+        self.backend.get_contact_display_name(&backend_contact_id)
+    }
+}
+
+impl<T: ContactResolverBackend> Default for ContactResolver<T>
+where
+    T::ContactID: From<AnyContactID>,
+    T::ContactID: Into<AnyContactID>,
+    T: Default,
+{
+    fn default() -> Self {
+        Self::new(T::default())
+    }
+}