Finish implementing the Contacts interface

src/padfoot/connection/contacts.rs

@@ -2,7 +2,7 @@ use crate::telepathy;
 
 use dbus::arg::{RefArg, Variant};
 use dbus::tree::MethodErr;
-use deltachat::contact::Contact;
+use deltachat::contact::{Contact, Origin};
 use std::collections::HashMap;
 
 use super::Connection;
@@ -80,7 +80,22 @@ impl telepathy::ConnectionInterfaceContacts for Connection {
             identifier,
             interfaces
         );
-        Err(MethodErr::no_arg()) // FIXME: should be NotImplemented?
+
+        let id = {
+            let ctx = &self.ctx.read().unwrap();
+            Contact::lookup_id_by_addr(ctx, identifier, Origin::Unknown)
+        };
+
+        if id == 0 {
+            return Err(MethodErr::no_arg()); // FIXME: should be InvalidHandle
+        };
+
+        let mut contacts = self.get_contact_attributes(vec![id], interfaces, true)?;
+        if let Some(contact) = contacts.remove(&id) {
+            Ok((id, contact))
+        } else {
+            Err(MethodErr::no_arg()) // FIXME: should be InvalidHandle
+        }
     }
 
     fn contact_attribute_interfaces(&self) -> Result<Vec<String>, MethodErr> {