Channel subscription, message sending, channel delete.

src/database/permissions/channel.rs

@@ -28,6 +28,23 @@ pub async fn calculate(user: &User, target: &Channel) -> ChannelPermissions<[u32
                 ChannelPermissions([ 0 ])
             }
         }
+        Channel::DirectMessage { recipients, .. } => {
+            if recipients.iter().find(|x| *x == &user.id).is_some() {
+                if let Some(recipient) = recipients
+                    .iter()
+                    .find(|x| *x != &user.id) {
+                    let perms = super::user::calculate(&user, recipient).await;
+
+                    if perms.get_send_message() {
+                        return ChannelPermissions([ ChannelPermission::View + ChannelPermission::SendMessage ]);
+                    }
+                    
+                    return ChannelPermissions([ ChannelPermission::View as u32 ]);
+                }
+            }
+
+            ChannelPermissions([ 0 ])
+        }
         _ => unreachable!()
     }
 }