# Slixmpp: The Slick XMPP Library
# Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
# This file is part of Slixmpp.
# See the file LICENSE for copying permissio
import slixmpp
from slixmpp.xmlstream import ElementBase, ET


class ChatState(ElementBase):

    """
    Example chat state stanzas:

    ::

        <message>
          <active xmlns="http://jabber.org/protocol/chatstates" />
        </message>

        <message>
          <paused xmlns="http://jabber.org/protocol/chatstates" />
        </message>

    """

    name = ''
    namespace = 'http://jabber.org/protocol/chatstates'
    plugin_attrib = 'chat_state'
    interfaces = {'chat_state'}
    sub_interfaces = interfaces
    is_extension = True

    states = {'active', 'composing', 'gone', 'inactive', 'paused'}

    def setup(self, xml=None):
        self.xml = ET.Element('')
        return True

    def get_chat_state(self):
        parent = self.parent()
        for state in self.states:
            state_xml = parent.xml.find('{%s}%s' % (self.namespace, state))
            if state_xml is not None:
                self.xml = state_xml
                return state
        return ''

    def set_chat_state(self, state):
        self.del_chat_state()
        parent = self.parent()
        if state in self.states:
            self.xml = ET.Element('{%s}%s' % (self.namespace, state))
            parent.append(self.xml)
        elif state not in [None, '']:
            raise ValueError('Invalid chat state')

    def del_chat_state(self):
        parent = self.parent()
        for state in self.states:
            state_xml = parent.xml.find('{%s}%s' % (self.namespace, state))
            if state_xml is not None:
                self.xml = ET.Element('')
                parent.xml.remove(state_xml)


class Active(ChatState):
    name = 'active'


class Composing(ChatState):
    name = 'composing'


class Gone(ChatState):
    name = 'gone'


class Inactive(ChatState):
    name = 'inactive'


class Paused(ChatState):
    name = 'paused'