Make the protocol advertise a requestable channel

Without this, telepathy-glib/empathy doesn't believe the protocol is
bonafide (i.e., implementing TP_PROTOCOL_FEATURE_CORE). Adding a dummy
gets empathy to display the protocol without needing to be patched \o/.

share/telepathy/managers/padfoot.manager

@@ -1,4 +1,5 @@
 [ConnectionManager]
+Interfaces=
 Name=padfoot
 BusName=org.freedesktop.Telepathy.ConnectionManager.padfoot
 ObjectPath=/org/freedesktop/Telepathy/ConnectionManager/padfoot
@@ -6,6 +7,16 @@ ObjectPath=/org/freedesktop/Telepathy/ConnectionManager/padfoot
 [Protocol delta]
 param-account=s required
 param-password=s required secret
+
+AuthenticationTypes=org.freedesktop.Telepathy.Channel.Type.ServerTLSConnection;
+ConnectionInterfaces=org.freedesktop.Telepathy.Connection.Interface.Requests;org.freedesktop.Telepathy.Connection.Interface.Contacts;
 EnglishName=Delta Chat
-VCardField=email
 Icon=im-delta
+Interfaces=
+RequestableChannelClasses=text;
+VCardField=email
+
+[text]
+org.freedesktop.Telepathy.Channel.ChannelType s=org.freedesktop.Telepathy.Channel.Type.Text
+org.freedesktop.Telepathy.Channel.TargetHandleType u=1
+allowed=org.freedesktop.Telepathy.Channel.TargetHandle;org.freedesktop.Telepathy.Channel.TargetID;

src/padfoot/connection_manager.rs

@@ -45,12 +45,17 @@ impl telepathy::ConnectionManager for ConnectionManager {
 
         props.insert(
             "org.freedesktop.Telepathy.Protocol.AuthenticationTypes".to_string(),
-            arg::Variant(Box::new(Vec::<String>::new())),
+            arg::Variant(Box::new(vec![
+                "org.freedesktop.Telepathy.Channel.Type.ServerTLSConnection".to_string(),
+            ])),
         );
 
         props.insert(
             "org.freedesktop.Telepathy.Protocol.ConnectionInterfaces".to_string(),
-            arg::Variant(Box::new(Vec::<String>::new())),
+            arg::Variant(Box::new(vec![
+                "org.freedesktop.Telepathy.Connection.Interface.Contacts".to_string(),
+                "org.freedesktop.Telepathy.Connection.Interface.Requests".to_string(),
+            ])),
         );
         props.insert(
             "org.freedesktop.Telepathy.Protocol.EnglishName".to_string(),
@@ -70,7 +75,7 @@ impl telepathy::ConnectionManager for ConnectionManager {
         );
         props.insert(
             "org.freedesktop.Telepathy.Protocol.RequestableChannelClasses".to_string(),
-            arg::Variant(Box::new(Vec::<String>::new())),
+            arg::Variant(Box::new(protocol::requestables())),
         );
         props.insert(
             "org.freedesktop.Telepathy.Protocol.VCardField".to_string(),

src/padfoot/protocol.rs

@@ -5,14 +5,20 @@ use std::collections::HashMap;
 #[derive(Debug)]
 pub struct Protocol {}
 
+pub type Variant = arg::Variant<Box<dyn arg::RefArg + 'static>>;
+
 pub type ParamSpec = (
-    String,                                       // Name
-    u32,                                          // Flags (Conn_Mgr_Param_Flags)
-    String,                                       // Signature
-    arg::Variant<Box<dyn arg::RefArg + 'static>>, // Default
+    String,  // Name
+    u32,     // Flags (Conn_Mgr_Param_Flags)
+    String,  // Signature
+    Variant, // Default
 );
 
-pub type Variant = arg::Variant<Box<dyn arg::RefArg + 'static>>;
+pub type RequestableChannelSpec = (
+    // Requestable_Channel_Class
+    HashMap<String, Variant>, // Fixed properties
+    Vec<String>,              // Allowed properties
+);
 
 pub const NAME: &'static str = "delta";
 
@@ -41,6 +47,29 @@ pub fn parameters() -> Vec<ParamSpec> {
     ]
 }
 
+pub fn requestables() -> Vec<RequestableChannelSpec> {
+    let mut rf = HashMap::<String, Variant>::new();
+
+    rf.insert(
+        "org.freedesktop.Telepathy.Channel.ChannelType".to_string(),
+        arg::Variant(Box::new(
+            "org.freedesktop.Telepathy.Channel.Type.Text".to_string(),
+        )),
+    );
+
+    rf.insert(
+        "org.freedesktop.Telepathy.Channel.TargetHandleType".to_string(),
+        arg::Variant(Box::new(1)),
+    );
+
+    let ra = vec![
+        "org.freedesktop.Telepathy.Channel.TargetHandle".to_string(),
+        "org.freedesktop.Telepathy.Channel.TargetID".to_string(),
+    ];
+
+    vec![(rf, ra)]
+}
+
 impl telepathy::Protocol for Protocol {
     fn identify_account(&self, params: HashMap<&str, Variant>) -> Result<String, tree::MethodErr> {
         println!("Protocol::identify_account({:?})", params);
@@ -68,39 +97,40 @@ impl telepathy::Protocol for Protocol {
     fn connection_interfaces(&self) -> Result<Vec<String>, tree::MethodErr> {
         println!("Protocol::connection_interfaces()");
 
-        Ok(vec![])
+        Ok(vec![
+            "org.freedesktop.Telepathy.Connection.Interface.Contacts".to_string(),
+            "org.freedesktop.Telepathy.Connection.Interface.Requests".to_string(),
+        ])
     }
-    fn requestable_channel_classes(
-        &self,
-    ) -> Result<
-        Vec<(
-            ::std::collections::HashMap<String, arg::Variant<Box<dyn arg::RefArg + 'static>>>,
-            Vec<String>,
-        )>,
-        tree::MethodErr,
-    > {
+    fn requestable_channel_classes(&self) -> Result<Vec<RequestableChannelSpec>, tree::MethodErr> {
         println!("Protocol::requestable_channel_classes()");
 
-        Ok(vec![])
+        Ok(requestables())
     }
+
     fn vcard_field(&self) -> Result<String, tree::MethodErr> {
         println!("Protocol::vcard_field()");
 
         Ok("email".to_string())
     }
+
     fn english_name(&self) -> Result<String, tree::MethodErr> {
         println!("Protocol::english_name()");
 
         Ok("Delta Chat".to_string())
     }
+
     fn icon(&self) -> Result<String, tree::MethodErr> {
         println!("Protocol::icon()");
 
         Ok("im-delta".to_string())
     }
+
     fn authentication_types(&self) -> Result<Vec<String>, tree::MethodErr> {
         println!("Protocol::authentication_types()");
 
-        Ok(vec![])
+        Ok(vec![
+            "org.freedesktop.Telepathy.Channel.Type.ServerTLSConnection".to_string(),
+        ])
     }
 }