"""
    SleekXMPP: The Sleek XMPP Library
    Copyright (C) 2010  Nathanael C. Fritz
    This file is part of SleekXMPP.

    See the file LICENSE for copying permission.
"""

from sleekxmpp.xmlstream import JID
from sleekxmpp.roster import RosterItem


class RosterNode(object):

    """
    A roster node is a roster for a single JID.

    Attributes:
        xmpp           -- The main SleekXMPP instance.
        jid            -- The JID that owns the roster node.
        db             -- Optional interface to an external datastore.
        auto_authorize -- Determines how authorizations are handled:
                            True  -- Accept all subscriptions.
                            False -- Reject all subscriptions.
                            None  -- Subscriptions must be
                                     manually authorized.
                          Defaults to True.
        auto_subscribe -- Determines if bi-directional subscriptions
                          are created after automatically authrorizing
                          a subscription request.
                          Defaults to True

    Methods:
        add         -- Add a JID to the roster.
        update      -- Update a JID's subscription information.
        subscribe   -- Subscribe to a JID.
        unsubscribe -- Unsubscribe from a JID.
        remove      -- Remove a JID from the roster.
        presence    -- Return presence information for a JID's resources.
    """

    def __init__(self, xmpp, jid, db=None):
        """
        Create a roster node for a JID.

        Arguments:
            xmpp -- The main SleekXMPP instance.
            jid  -- The JID that owns the roster.
            db   -- Optional interface to an external datastore.
        """
        self.xmpp = xmpp
        self.jid = jid
        self.db = db
        self.auto_authorize = True
        self.auto_subscribe = True
        self._jids = {}

        if self.db:
            for jid in self.db.entries(self.jid):
                self.add(jid)

    def __getitem__(self, key):
        """
        Return the roster item for a subscribed JID.

        A new item entry will be created if one does not already exist.
        """
        if isinstance(key, JID):
            key = key.bare
        if key not in self._jids:
            self.add(key, save=True)
        return self._jids[key]

    def keys(self):
        """Return a list of all subscribed JIDs."""
        return self._jids.keys()

    def has_jid(self, jid):
        """Returns whether the roster has a JID."""
        return jid in self._jids

    def __iter__(self):
        """Iterate over the roster items."""
        return self._jids.__iter__()

    def set_backend(self, db=None):
        """
        Set the datastore interface object for the roster node.

        Arguments:
            db -- The new datastore interface.
        """
        self.db = db
        for jid in self.db.entries(self.jid):
            self.add(jid)
        for jid in self._jids:
            self._jids[jid].set_backend(db)

    def add(self, jid, name='', groups=None, afrom=False, ato=False,
            pending_in=False, pending_out=False, whitelisted=False,
            save=False):
        """
        Add a new roster item entry.

        Arguments:
            jid         -- The JID for the roster item.
            name        -- An alias for the JID.
            groups      -- A list of group names.
            afrom       -- Indicates if the JID has a subscription state
                           of 'from'. Defaults to False.
            ato         -- Indicates if the JID has a subscription state
                           of 'to'. Defaults to False.
            pending_in  -- Indicates if the JID has sent a subscription
                           request to this connection's JID.
                           Defaults to False.
            pending_out -- Indicates if a subscription request has been sent
                           to this JID.
                           Defaults to False.
            whitelisted -- Indicates if a subscription request from this JID
                           should be automatically authorized.
                           Defaults to False.
            save        -- Indicates if the item should be persisted
                           immediately to an external datastore,
                           if one is used.
                           Defaults to False.
        """
        if isinstance(jid, JID):
            key = jid.bare
        state = {'name': name,
                 'groups': groups or [],
                 'from': afrom,
                 'to': ato,
                 'pending_in': pending_in,
                 'pending_out': pending_out,
                 'whitelisted': whitelisted,
                 'subscription': 'none'}
        self._jids[jid] = RosterItem(self.xmpp, jid, self.jid,
                                     state=state, db=self.db)
        if save:
            self._jids[jid].save()

    def subscribe(self, jid):
        """
        Subscribe to the given JID.

        Arguments:
            jid -- The JID to subscribe to.
        """
        self[jid].subscribe()

    def unsubscribe(self, jid):
        """
        Unsubscribe from the given JID.

        Arguments:
            jid -- The JID to unsubscribe from.
        """
        self[jid].unsubscribe()

    def remove(self, jid):
        """
        Remove a JID from the roster.

        Arguments:
            jid -- The JID to remove.
        """
        self[jid].remove()
        if not self.xmpp.is_component:
            self.update(jid, subscription='remove')

    def update(self, jid, name=None, subscription=None, groups=[]):
        """
        Update a JID's subscription information.

        Arguments:
            jid          -- The JID to update.
            name         -- Optional alias for the JID.
            subscription -- The subscription state. May be one of: 'to',
                            'from', 'both', 'none', or 'remove'.
            groups       -- A list of group names.
        """
        self[jid]['name'] = name
        self[jid]['groups'] = group
        self[jid].save()

        if not self.xmpp.is_component:
            iq = self.Iq()
            iq['type'] = 'set'
            iq['roster']['items'] = {jid: {'name': name,
                                           'subscription': subscription,
                                           'groups': groups}}
            response = iq.send()
            return response and response['type'] == 'result'

    def presence(self, jid, resource=None):
        """
        Retrieve the presence information of a JID.

        May return either all online resources' status, or
        a single resource's status.

        Arguments:
            jid      -- The JID to lookup.
            resource -- Optional resource for returning
                        only the status of a single connection.
        """
        if resource is None:
            return self[jid].resources

        default_presence = {'status': '',
                            'priority': 0,
                            'show': ''}
        return self[jid].resources.get(resource,
                                       default_presence)

    def reset(self):
        """
        Reset the state of the roster to forget any current
        presence information. Useful after a disconnection occurs.
        """
        for jid in self:
            self[jid].reset()