#!/usr/bin/env python2
# -*- coding: utf-8 -*-

# SAT plugin for Pubsub Schemas
# Copyright (C) 2009-2017 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.i18n import _
from sat.core import exceptions
from sat.core.constants import Const as C
from sat.tools import xml_tools
from twisted.words.protocols.jabber import jid
from twisted.words.protocols.jabber.xmlstream import XMPPHandler
from twisted.internet import defer
from sat.core.log import getLogger
log = getLogger(__name__)
from wokkel import disco, iwokkel
from wokkel import data_form
from wokkel import generic
from zope.interface import implements
from collections import Iterable
import copy

NS_SCHEMA = 'https://salut-a-toi/protocol/schema:0'

PLUGIN_INFO = {
    C.PI_NAME: "PubSub Schema",
    C.PI_IMPORT_NAME: "PUBSUB_SCHEMA",
    C.PI_TYPE: "EXP",
    C.PI_PROTOCOLS: [],
    C.PI_DEPENDENCIES: ["XEP-0060"],
    C.PI_MAIN: "PubsubSchema",
    C.PI_HANDLER: "yes",
    C.PI_DESCRIPTION: _("""Handle Pubsub data schemas""")
}


class PubsubSchema(object):

    def __init__(self, host):
        log.info(_(u"PubSub Schema initialization"))
        self.host = host
        self._p = self.host.plugins["XEP-0060"]
        host.bridge.addMethod("psSchemaGet", ".plugin",
                              in_sign='sss', out_sign='s',
                              method=self._getSchema,
                              async=True
                              )
        host.bridge.addMethod("psSchemaSet", ".plugin",
                              in_sign='ssss', out_sign='',
                              method=self._setSchema,
                              async=True
                              )
        host.bridge.addMethod("psSchemaUIGet", ".plugin",
                              in_sign='sss', out_sign='s',
                              method=self._getUISchema,
                              async=True
                              )
        host.bridge.addMethod("psItemsFormGet", ".plugin",
                              in_sign='ssssiassa{ss}s', out_sign='(asa{ss})',
                              method=self._getDataFormItems,
                              async=True)
        host.bridge.addMethod("psItemFormSend", ".plugin",
                              in_sign='ssa{sas}ssa{ss}s', out_sign='s',
                              method=self._sendDataFormItem,
                              async=True)

    def getHandler(self, client):
        return SchemaHandler()

    def _getSchemaBridgeCb(self, schema_elt):
        if schema_elt is None:
            return u''
        return schema_elt.toXml()

    def _getSchema(self, service, nodeIdentifier, profile_key=C.PROF_KEY_NONE):
        client = self.host.getClient(profile_key)
        service = None if not service else jid.JID(service)
        d = self.getSchema(client, service, nodeIdentifier)
        d.addCallback(self._getSchemaBridgeCb)
        return d

    def _getSchemaCb(self, iq_elt):
        try:
            schema_elt = next(iq_elt.elements(NS_SCHEMA, 'schema'))
        except StopIteration:
            raise exceptions.DataError('missing <schema> element')
        try:
            x_elt = next(schema_elt.elements((data_form.NS_X_DATA, 'x')))
        except StopIteration:
            # there is not schema on this node
            return None
        return x_elt

    def getSchema(self, client, service, nodeIdentifier):
        """retrieve PubSub node schema

        @param service(jid.JID, None): jid of PubSub service
            None to use our PEP
        @param nodeIdentifier(unicode): node to get schema from
        @return (domish.Element, None): schema (<x> element)
            None if not schema has been set on this node
        """
        iq_elt = client.IQ(u'get')
        if service is not None:
            iq_elt['to'] = service.full()
        pubsub_elt = iq_elt.addElement((NS_SCHEMA, 'pubsub'))
        schema_elt = pubsub_elt.addElement((NS_SCHEMA, 'schema'))
        schema_elt['node'] = nodeIdentifier
        d = iq_elt.send()
        d.addCallback(self._getSchemaCb)
        return d

    @defer.inlineCallbacks
    def getSchemaForm(self, client, service, nodeIdentifier, schema=None, form_type='form', copy_form=True):
        """get data form from node's schema

        @param service(None, jid.JID): PubSub service
        @param nodeIdentifier(unicode): node
        @param schema(domish.Element, data_form.Form, None): node schema
            if domish.Element, will be converted to data form
            if data_form.Form it will be returned without modification
            if None, it will be retrieved from node (imply one additional XMPP request)
        @param form_type(unicode): type of the form
        @param copy_form(bool): if True and if schema is already a data_form.Form, will deep copy it before returning
            needed when the form is reused and it will be modified (e.g. in sendDataFormItem)
        @return(data_form.Form): data form
            the form should not be modified if copy_form is not set
        """
        if schema is None:
            log.debug(_(u"unspecified schema, we need to request it"))
            schema = yield self.getSchema(client, service, nodeIdentifier)
            if schema is None:
                raise exceptions.DataError(_(u"no schema specified, and this node has no schema either, we can't construct the data form"))
        elif isinstance(schema, data_form.Form):
            if copy_form:
                schema = copy.deepcopy(schema)
            defer.returnValue(schema)

        try:
            form = data_form.Form.fromElement(schema)
        except data_form.Error as e:
            raise exceptions.DataError(_(u"Invalid Schema: {msg}").format(
                msg = e))
        form.formType = form_type
        defer.returnValue(form)

    def schema2XMLUI(self, schema_elt):
        form = data_form.Form.fromElement(schema_elt)
        xmlui = xml_tools.dataForm2XMLUI(form, '')
        return xmlui

    def _getUISchema(self, service, nodeIdentifier, profile_key=C.PROF_KEY_NONE):
        client = self.host.getClient(profile_key)
        service = None if not service else jid.JID(service)
        d = self.getUISchema(client, service, nodeIdentifier)
        d.addCallback(lambda xmlui: xmlui.toXml())
        return d

    def getUISchema(self, client, service, nodeIdentifier):
        d = self.getSchema(client, service, nodeIdentifier)
        d.addCallback(self.schema2XMLUI)
        return d

    def _setSchema(self, service, nodeIdentifier, schema, profile_key=C.PROF_KEY_NONE):
        client = self.host.getClient(profile_key)
        service = None if not service else jid.JID(service)
        schema = generic.parseXml(schema.encode('utf-8'))
        return self.setSchema(client, service, nodeIdentifier, schema)

    def setSchema(self, client, service, nodeIdentifier, schema):
        """set or replace PubSub node schema

        @param schema(domish.Element, None): schema to set
            None if schema need to be removed
        """
        iq_elt = client.IQ()
        if service is not None:
            iq_elt['to'] = service.full()
        pubsub_elt = iq_elt.addElement((NS_SCHEMA, 'pubsub'))
        schema_elt = pubsub_elt.addElement((NS_SCHEMA, 'schema'))
        schema_elt['node'] = nodeIdentifier
        if schema is not None:
            schema_elt.addChild(schema)
        return iq_elt.send()

    def _getDataFormItems(self, form_ns='', service='', node='', schema='', max_items=10, item_ids=None, sub_id=None, extra_dict=None, profile_key=C.PROF_KEY_NONE):
        client = self.host.getClient(profile_key)
        service = jid.JID(service) if service else None
        if not node:
            raise exceptions.DataError(_(u'empty node is not allowed'))
        if schema:
            schema = generic.parseXml(schema.encode('utf-8'))
        else:
            schema = None
        max_items = None if max_items == C.NO_LIMIT else max_items
        extra = self._p.parseExtra(extra_dict)
        d = self.getDataFormItems(client, form_ns or None, service, node, schema, max_items or None, item_ids, sub_id or None, extra.rsm_request, extra.extra)
        d.addCallback(self._p.serItemsData)
        return d

    @defer.inlineCallbacks
    def getDataFormItems(self, client, form_ns, service, nodeIdentifier, schema=None, max_items=None, item_ids=None, sub_id=None, rsm_request=None, extra=None, filters=None):
        """Get items known as being data forms, and convert them to XMLUI

        @param form_ns (unicode, None): namespace of the form
            None to accept everything, even if form has no namespace
        @param schema(domish.Element, data_form.Form, None): schema of the node if known
            if None, it will be retrieved from node
        @param filters(dict, None): same as for xml_tools.dataFormResult2XMLUI
        other parameters as the same as for [getItems]
        @return (list[unicode]): XMLUI of the forms
            if an item is invalid (not corresponding to form_ns or not a data_form)
            it will be skipped
        """
        # we need the initial form to get options of fields when suitable
        schema_form = yield self.getSchemaForm(client, service, nodeIdentifier, schema, form_type='result', copy_form=False)
        items_data = yield self._p.getItems(client, service, nodeIdentifier, max_items, item_ids, sub_id, rsm_request, extra)
        items, metadata = items_data
        items_xmlui = []
        for item_elt in items:
            for x_elt in item_elt.elements((data_form.NS_X_DATA, u'x')):
                form = data_form.Form.fromElement(x_elt)
                if form_ns and form.formNamespace != form_ns:
                    continue
                xmlui = xml_tools.dataFormResult2XMLUI(
                    form,
                    schema_form,
                    prepend = (('label', 'id'),('text', item_elt['id'], u'id')),
                    filters = filters,
                    )
                items_xmlui.append(xmlui)
                break
        defer.returnValue((items_xmlui, metadata))


    def _sendDataFormItem(self, service, nodeIdentifier, values, schema=None, item_id=None, extra=None, profile_key=C.PROF_KEY_NONE):
        client = self.host.getClient(profile_key)
        service = None if not service else jid.JID(service)
        if schema:
            schema = generic.parseXml(schema.encode('utf-8'))
        else:
            schema = None
        d = self.sendDataFormItem(client, service, nodeIdentifier, values, schema, item_id or None, extra, deserialise=True)
        d.addCallback(lambda ret: ret or u'')
        return d

    @defer.inlineCallbacks
    def sendDataFormItem(self, client, service, nodeIdentifier, values, schema=None, item_id=None, extra=None, deserialise=False):
        """Publish an item as a dataform when we know that there is a schema

        @param values(dict[[iterable[object], object]): values set for the form
            if not iterable, will be put in a list
        @param schema(domish.Element, data_form.Form, None): data schema
            None to retrieve data schema from node (need to do a additional XMPP call)
            Schema is needed to construct data form to publish
        @param deserialise(bool): if True, data are list of unicode and must be deserialized according to expected type
            This is done in this method and not directly in _sendDataFormItem because we need to know the data type
            which is in the form, not availablable in _sendDataFormItem
        other parameters as the same as for [self._p.sendItem]
        """
        form = yield self.getSchemaForm(client, service, nodeIdentifier, schema, form_type='submit')

        for name, values_list in values.iteritems():
            try:
                field = form.fields[name]
            except KeyError:
                log.warning(_(u"field {name} doesn't exist, ignoring it").format(name=name))
                continue
            if isinstance(values_list, basestring) or not isinstance(values_list, Iterable):
                values_list = [values_list]
            if deserialise:
                if field.fieldType == 'boolean':
                    values_list = [C.bool(v) for v in values_list]
                elif 'jid' in field.fieldType:
                    values_list = [jid.JID(v) for v in values_list]
            if 'list' in field.fieldType:
                # for lists, we check that given values are allowed in form
                allowed_values = [o.value for o in field.options]
                values_list = [v for v in values_list if v in allowed_values]
                if not values_list:
                    # if values don't map to allowed values, we use default ones
                    values_list = field.values
            field.values = values_list

        yield self._p.sendItem(client, service, nodeIdentifier, form.toElement(), item_id, extra)


class SchemaHandler(XMPPHandler):
    implements(iwokkel.IDisco)

    def getDiscoInfo(self, requestor, service, nodeIdentifier=''):
        return [disco.DiscoFeature(NS_SCHEMA)]

    def getDiscoItems(self, requestor, service, nodeIdentifier=''):
        return []