# `chatstates` – Chat State Notification support (XEP-0085)

This module provides support to implement Chat State Notifications.

## XSOs

The module registers an attribute `xep0085_chatstate` with `aioxmpp.Message` to represent the chat state notification tags, it takes values from the following enumeration (or `None` if no tag is present):

class `aioxmpp.chatstates.``ChatState`

  Enumeration of the chat states defined by XEP-0085:

  `ACTIVE`
  `COMPOSING`
  `PAUSED`
  `INACTIVE`
  `GONE`

## Helpers

The module provides the following helper class, that handles the state management for chat state notifications:

class `aioxmpp.chatstates.``ChatStateManager`(strategy=None)

  Manage the state of our chat state.

  Parameters: | strategy (a subclass of `ChatStateStrategy`) – the strategy used to decide whether to send notifications (defaults to `DiscoverSupport`)

  `handle`(state, message=False)

    Handle a state update.

    Parameters:

    - state (`ChatState`) – the new chat state
    - message (`bool`) – pass true to indicate that we handle the `ACTIVE` state that is implied by sending a content message.

    Returns: | whether a standalone notification must be sent for this state update, respective if a chat state notification must be included with the message.
    Raises: | ValueError – if message is true and a state other than `ACTIVE` is passed.

  Methods to pass in protocol level information:

  `no_reply`()

    Call this method if the peer did not include a chat state notification.

  `reset`()

    Call this method on connection reset.

Its operation is controlled by one of the chat state strategies:

class `aioxmpp.chatstates.``DoNotEmit`

  Chat state strategy: Do not emit chat state notifications.

class `aioxmpp.chatstates.``DiscoverSupport`

  Chat state strategy: Discover support for chat state notifications as per section 5.1 of XEP-0085.

class `aioxmpp.chatstates.``AlwaysEmit`

  Chat state strategy: Always emit chat state notifications.