Move presence specific sections from intro to presence module

specification/0-intro.rst

@@ -338,49 +338,6 @@ Usage of an IS is not required in order for a client application to be part of
 the Matrix ecosystem. However, without one clients will not be able to look up
 user IDs using 3PIDs.
 
-Presence
-~~~~~~~~
-
-Each user has the concept of presence information. This encodes:
-
- * Whether the user is currently online
- * How recently the user was last active (as seen by the server)
- * Whether a given client considers the user to be currently idle
- * Arbitrary information about the user's current status (e.g. "in a meeting").
-
-This information is collated from both per-device (online; idle; last_active) and
-per-user (status) data, aggregated by the user's homeserver and transmitted as
-an ``m.presence`` event. This is one of the few events which are sent *outside
-the context of a room*. Presence events are sent to all users who subscribe to
-this user's presence through a presence list or by sharing membership of a room.
-
-.. TODO
-  How do we let users hide their presence information?
-
-.. TODO
-  The last_active specifics should be moved to the detailed presence event section
-  
-Last activity is tracked by the server maintaining a timestamp of the last time
-it saw a pro-active event from the user. Any event which could be triggered by a
-human using the application is considered pro-active (e.g. sending an event to a
-room). An example of a non-proactive client activity would be a client setting
-'idle' presence status, or polling for events. This timestamp is presented via a
-key called ``last_active_ago``, which gives the relative number of milliseconds
-since the message is generated/emitted that the user was last seen active.
-
-N.B. in v1 API, status/online/idle state are muxed into a single 'presence'
-field on the ``m.presence`` event.
-
-Presence Lists
-~~~~~~~~~~~~~~
-
-Each user's home server stores a "presence list". This stores a list of user IDs
-whose presence the user wants to follow.
-
-To be added to this list, the user being added must be invited by the list owner
-and accept the invitation. Once accepted, both user's HSes track the
-subscription.
-
 
 Profiles
 ~~~~~~~~

specification/modules/presence.rst

@@ -1,6 +1,24 @@
 Presence
 ========
 
+Each user has the concept of presence information. This encodes:
+
+ * Whether the user is currently online
+ * How recently the user was last active (as seen by the server)
+ * Whether a given client considers the user to be currently idle
+ * Arbitrary information about the user's current status (e.g. "in a meeting").
+
+This information is collated from both per-device (``online``, ``idle``,
+``last_active``) and per-user (status) data, aggregated by the user's homeserver
+and transmitted as an ``m.presence`` event. This is one of the few events which
+are sent *outside the context of a room*. Presence events are sent to all users
+who subscribe to this user's presence through a presence list or by sharing
+membership of a room.
+
+A presence list is a list of user IDs whose presence the user wants to follow.
+To be added to this list, the user being added must be invited by the list owner
+who must accept the invitation.
+ 
 Each user has presence information associated with them. This encodes the
 "availability" of that user, suitable for display on other clients.
 This is transmitted as an ``m.presence`` event and is one of the few events
@@ -16,6 +34,7 @@ represented by the ``presence`` key, which is an enum of one of the following:
       - ``free_for_chat`` : The user is generally willing to receive messages
         moreso than default.
  
+
 Events
 ------
 
@@ -24,7 +43,8 @@ Events
 Client behaviour
 ----------------
 
-Clients can manually set/get their presence using the HTTP APIs listed below.
+Clients can manually set/get their presence/presence list using the HTTP APIs
+listed below.
 
 {{presence_http_api}}
 
@@ -43,6 +63,9 @@ recommended.
 Server behaviour
 ----------------
 
+Each user's home server stores a "presence list" per user. Once a user accepts
+a presence list, both user's HSes must track the subscription.
+
 Propagating profile information
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -58,10 +81,12 @@ home server when a user successfully changes their display name or avatar URL.
 
   The intention for sending this information in ``m.presence`` is so that any
   "user list" can display the *current* name/presence for a user ID outside the
-  scope of a room (e.g. a user page which has a "start conversation" button).
-  This is bundled into a single event to avoid "flickering" on this page which
-  can occur if you received presence first and then display name later (the
-  user's name would flicker from their user ID to the display name).
+  scope of a room e.g. for a user page. This is bundled into a single event for
+  several reasons. The user's display name can change per room. This
+  event provides the "canonical" name for the user. In addition, the name is
+  bundled into a single event for the ease of client implementations. If this
+  was not done, the client would need to search all rooms for their own
+  membership event to pull out the display name.
 
 
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