# copyright 2003-2014 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb 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 Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""edit entity attributes/relations from any view, without going to the entity
form
"""


from cubicweb import _

import copy

from logilab.mtconverter import xml_escape
from logilab.common.decorators import cached

from cubicweb import neg_role
from cubicweb.schema import display_name
from cubicweb.utils import json, json_dumps
from cubicweb.predicates import non_final_entity, match_kwargs
from cubicweb.view import EntityView
from cubicweb.web import stdmsgs
from cubicweb.web.views import uicfg
from cubicweb.web.form import FieldNotFound
from cubicweb.web.formwidgets import Button, SubmitButton
from cubicweb.web.views.ajaxcontroller import ajaxfunc

class _DummyForm(object):
    __slots__ = ('event_args',)
    def form_render(self, **_args):
        return u''
    def render(self, *_args, **_kwargs):
        return u''
    def append_field(self, *args):
        pass
    def add_hidden(self, *args):
        pass

class AutoClickAndEditFormView(EntityView):
    __regid__ = 'reledit'
    __select__ = non_final_entity() & match_kwargs('rtype')

    # ui side continuations
    _onclick = (u"cw.reledit.loadInlineEditionForm('%(formid)s', %(eid)s, '%(rtype)s', '%(role)s', "
                "'%(divid)s', %(reload)s, '%(vid)s', '%(action)s');")
    _cancelclick = "cw.reledit.cleanupAfterCancel('%s')"

    # ui side actions/buttons
    _addzone = u'<img title="%(msg)s" src="%(logo)s" alt="%(msg)s"/>'
    _addmsg = _('click to add a value')
    _addlogo = 'plus.png'
    _deletezone = u'<img title="%(msg)s" src="%(logo)s" alt="%(msg)s"/>'
    _deletemsg = _('click to delete this value')
    _deletelogo = 'cancel.png'
    _editzone = u'<img title="%(msg)s" src="%(logo)s" alt="%(msg)s"/>'
    _editzonemsg = _('click to edit this field')
    _editlogo = 'pen_icon.png'

    # renderer
    _form_renderer_id = 'base'

    def entity_call(self, entity, rtype=None, role='subject',
                    reload=False, # controls reloading the whole page after change
                                  # boolean, eid (to redirect), or
                                  # function taking the subject entity & returning a boolean or an eid
                    rvid=None,    # vid to be applied to other side of rtype (non final relations only)
                    default_value=None,
                    formid='base',
                    action=None
                    ):
        """display field to edit entity's `rtype` relation on click"""
        assert rtype
        self._cw.add_css('cubicweb.form.css')
        self._cw.add_js(('cubicweb.reledit.js', 'cubicweb.edition.js', 'cubicweb.ajax.js'))
        self.entity = entity
        rschema = self._cw.vreg.schema[rtype]
        rctrl = self._cw.vreg['uicfg'].select('reledit', self._cw, entity=entity)
        self._rules = rctrl.etype_get(self.entity.e_schema.type, rschema.type, role, '*')
        reload = self._compute_reload(rschema, role, reload)
        divid = self._build_divid(rtype, role, self.entity.eid)
        if rschema.final:
            self._handle_attribute(rschema, role, divid, reload, action)
        else:
            if self._is_composite():
                self._handle_composite(rschema, role, divid, reload, formid, action)
            else:
                self._handle_relation(rschema, role, divid, reload, formid, action)

    def _handle_attribute(self, rschema, role, divid, reload, action):
        rvid = self._rules.get('rvid', None)
        if rvid is not None:
            value = self._cw.view(rvid, entity=self.entity,
                                  rtype=rschema.type, role=role)
        else:
            value = self.entity.printable_value(rschema.type)
        if not self._should_edit_attribute(rschema):
            self.w(value)
            return
        form, renderer = self._build_form(self.entity, rschema, role, divid,
                                          'base', reload, action)
        value = value or self._compute_default_value(rschema, role)
        self.view_form(divid, value, form, renderer)

    def _compute_formid_value(self, rschema, role, rvid, formid):
        related_rset = self.entity.related(rschema.type, role)
        if related_rset:
            value = self._cw.view(rvid, related_rset)
        else:
            value = self._compute_default_value(rschema, role)
        if not self._should_edit_relation(rschema, role):
            return None, value
        return formid, value

    def _handle_relation(self, rschema, role, divid, reload, formid, action):
        rvid = self._rules.get('rvid', 'autolimited')
        formid, value = self._compute_formid_value(rschema, role, rvid, formid)
        if formid is None:
            return self.w(value)
        form, renderer = self._build_form(self.entity,  rschema, role, divid, formid,
                                          reload, action, dict(vid=rvid))
        self.view_form(divid, value, form, renderer)

    def _handle_composite(self, rschema, role, divid, reload, formid, action):
        # this is for attribute-like composites (1 target type, 1 related entity at most, for now)
        entity = self.entity
        related_rset = entity.related(rschema.type, role)
        add_related = self._may_add_related(related_rset, rschema, role)
        edit_related = self._may_edit_related_entity(related_rset, rschema, role)
        delete_related = edit_related and self._may_delete_related(related_rset, rschema, role)
        rvid = self._rules.get('rvid', 'autolimited')
        formid, value = self._compute_formid_value(rschema, role, rvid, formid)
        if formid is None or not (edit_related or add_related):
            # till we learn to handle cases where not (edit_related or add_related)
            self.w(value)
            return
        form, renderer = self._build_form(entity, rschema, role, divid, formid,
                                          reload, action, dict(vid=rvid))
        self.view_form(divid, value, form, renderer,
                       edit_related, add_related, delete_related)

    @cached
    def _compute_ttypes(self, rschema, role):
        dual_role = neg_role(role)
        return getattr(rschema, '%ss' % dual_role)()

    def _compute_reload(self, rschema, role, reload):
        ctrl_reload = self._rules.get('reload', reload)
        if callable(ctrl_reload):
            ctrl_reload = ctrl_reload(self.entity)
        if isinstance(ctrl_reload, int) and ctrl_reload > 1: # not True/False
            ctrl_reload = self._cw.build_url(ctrl_reload)
        return ctrl_reload

    def _compute_default_value(self, rschema, role):
        default = self._rules.get('novalue_label')
        if default is None:
            if self._rules.get('novalue_include_rtype'):
                default = self._cw._('<%s not specified>') % display_name(
                    self._cw, rschema.type, role)
            else:
                default = self._cw._('<not specified>')
        else:
            default = self._cw._(default)
        return xml_escape(default)

    def _is_composite(self):
        return self._rules.get('edit_target') == 'related'

    def _may_add_related(self, related_rset, rschema, role):
        """ ok for attribute-like composite entities """
        ttypes = self._compute_ttypes(rschema, role)
        if len(ttypes) > 1: # many etypes: learn how to do it
            return False
        rdef = rschema.role_rdef(self.entity.e_schema, ttypes[0], role)
        card = rdef.role_cardinality(role)
        if related_rset or card not in '?1':
            return False
        if role == 'subject':
            kwargs = {'fromeid': self.entity.eid}
        else:
            kwargs = {'toeid': self.entity.eid}
        return rdef.has_perm(self._cw, 'add', **kwargs)

    def _may_edit_related_entity(self, related_rset, rschema, role):
        """ controls the edition of the related entity """
        ttypes = self._compute_ttypes(rschema, role)
        if len(ttypes) > 1 or len(related_rset.rows) != 1:
            return False
        if self.entity.e_schema.rdef(rschema, role).role_cardinality(role) not in '?1':
            return False
        return related_rset.get_entity(0, 0).cw_has_perm('update')

    def _may_delete_related(self, related_rset, rschema, role):
        # we assume may_edit_related, only 1 related entity
        if not related_rset:
            return False
        rentity = related_rset.get_entity(0, 0)
        entity = self.entity
        if role == 'subject':
            kwargs = {'fromeid': entity.eid, 'toeid': rentity.eid}
            cardinality = rschema.rdefs[(entity.cw_etype, rentity.cw_etype)].cardinality[0]
        else:
            kwargs = {'fromeid': rentity.eid, 'toeid': entity.eid}
            cardinality = rschema.rdefs[(rentity.cw_etype, entity.cw_etype)].cardinality[1]
        if cardinality in '1+':
            return False
        # NOTE: should be sufficient given a well built schema/security
        return rschema.has_perm(self._cw, 'delete', **kwargs)

    def _build_zone(self, zonedef, msg, logo):
        return zonedef % {'msg': xml_escape(self._cw._(msg)),
                          'logo': xml_escape(self._cw.data_url(logo))}

    def _build_edit_zone(self):
        return self._build_zone(self._editzone, self._editzonemsg, self._editlogo)

    def _build_delete_zone(self):
        return self._build_zone(self._deletezone, self._deletemsg, self._deletelogo)

    def _build_add_zone(self):
        return self._build_zone(self._addzone, self._addmsg, self._addlogo)

    def _build_divid(self, rtype, role, entity_eid):
        """ builds an id for the root div of a reledit widget """
        return '%s-%s-%s' % (rtype, role, entity_eid)

    def _build_args(self, entity, rtype, role, formid, reload, action,
                    extradata=None):
        divid = self._build_divid(rtype, role, entity.eid)
        event_args = {'divid' : divid, 'eid' : entity.eid, 'rtype' : rtype, 'formid': formid,
                      'reload' : json_dumps(reload), 'action': action,
                      'role' : role, 'vid' : u''}
        if extradata:
            event_args.update(extradata)
        return event_args

    def _prepare_form(self, entity, rschema, role, action):
        assert action in ('edit_rtype', 'edit_related', 'add', 'delete'), action
        if action == 'edit_rtype':
            return False, entity
        label = True
        if action in ('edit_related', 'delete'):
            edit_entity = entity.related(rschema, role).get_entity(0, 0)
        elif action == 'add':
            add_etype = self._compute_ttypes(rschema, role)[0]
            _new_entity = self._cw.vreg['etypes'].etype_class(add_etype)(self._cw)
            _new_entity.eid = next(self._cw.varmaker)
            edit_entity = _new_entity
            # XXX see forms.py ~ 276 and entities.linked_to method
            #     is there another way?
            self._cw.form['__linkto'] = '%s:%s:%s' % (rschema, entity.eid, neg_role(role))
        assert edit_entity
        return label, edit_entity

    def _build_renderer(self, related_entity, display_label):
        return self._cw.vreg['formrenderers'].select(
            self._form_renderer_id, self._cw, entity=related_entity,
            display_label=display_label,
            table_class='attributeForm' if display_label else '',
            display_help=False, button_bar_class='buttonbar',
            display_progress_div=False)

    def _build_form(self, entity, rschema, role, divid, formid, reload, action,
                    extradata=None, **formargs):
        rtype = rschema.type
        event_args = self._build_args(entity, rtype, role, formid, reload, action, extradata)
        if not action:
            form = _DummyForm()
            form.event_args = event_args
            return form, None
        label, edit_entity = self._prepare_form(entity, rschema, role, action)
        cancelclick = self._cancelclick % divid
        form = self._cw.vreg['forms'].select(
            formid, self._cw, rset=edit_entity.as_rset(), entity=edit_entity,
            domid='%s-form' % divid, formtype='inlined',
            action=self._cw.build_url('validateform', __onsuccess='window.parent.cw.reledit.onSuccess'),
            cwtarget='eformframe', cssclass='releditForm',
            **formargs)
        # pass reledit arguments
        for pname, pvalue in event_args.items():
            form.add_hidden('__reledit|' + pname, pvalue)
        # handle buttons
        if form.form_buttons: # edition, delete
            form_buttons = []
            for button in form.form_buttons:
                if not button.label.endswith('apply'):
                    if button.label.endswith('cancel'):
                        button = copy.deepcopy(button)
                        button.cwaction = None
                        button.onclick = cancelclick
                        if 'class' in button.attrs:
                            new_class = button.attrs['class'].replace('cwjs-edition-cancel', '')
                            button.attrs['class'] = new_class
                    form_buttons.append(button)
            form.form_buttons = form_buttons
        else: # base
            form.form_buttons = [SubmitButton(),
                                 Button(stdmsgs.BUTTON_CANCEL, onclick=cancelclick)]
        form.event_args = event_args
        if formid == 'base':
            field = form.field_by_name(rtype, role, entity.e_schema)
            form.append_field(field)
        return form, self._build_renderer(edit_entity, label)

    def _should_edit_attribute(self, rschema):
        entity = self.entity
        rdef = entity.e_schema.rdef(rschema)
        # check permissions
        if not entity.cw_has_perm('update'):
            return False
        rdef = entity.e_schema.rdef(rschema)
        return rdef.has_perm(self._cw, 'update', eid=entity.eid)

    def _should_edit_relation(self, rschema, role):
        eeid = self.entity.eid
        perm_args = {'fromeid': eeid} if role == 'subject' else {'toeid': eeid}
        return rschema.has_perm(self._cw, 'add', **perm_args)

    def _open_form_wrapper(self, divid, value, form, renderer,
                           _edit_related, _add_related, _delete_related):
        w = self.w
        w(u'<div id="%(id)s-reledit" onmouseout="%(out)s" onmouseover="%(over)s" class="%(css)s">' %
          {'id': divid, 'css': 'releditField',
           'out': "jQuery('#%s').addClass('invisible')" % divid,
           'over': "jQuery('#%s').removeClass('invisible')" % divid})
        w(u'<div id="%s-value" class="editableFieldValue">' % divid)
        w(value)
        w(u'</div>')
        form.render(w=w, renderer=renderer)
        w(u'<div id="%s" class="editableField invisible">' % divid)

    def _edit_action(self, divid, args, edit_related, add_related, _delete_related):
        # XXX disambiguate wrt edit_related
        if not add_related: # currently, excludes edition
            w = self.w
            args['formid'] = 'edition' if edit_related else 'base'
            args['action'] = 'edit_related' if edit_related else 'edit_rtype'
            w(u'<div id="%s-update" class="editableField" onclick="%s" title="%s">' %
              (divid, xml_escape(self._onclick % args), self._cw._(self._editzonemsg)))
            w(self._build_edit_zone())
            w(u'</div>')

    def _add_action(self, divid, args, _edit_related, add_related, _delete_related):
        if add_related:
            w = self.w
            args['formid'] = 'edition'
            args['action'] = 'add'
            w(u'<div id="%s-add" class="editableField" onclick="%s" title="%s">' %
              (divid, xml_escape(self._onclick % args), self._cw._(self._addmsg)))
            w(self._build_add_zone())
            w(u'</div>')

    def _del_action(self, divid, args, _edit_related, _add_related, delete_related):
        if delete_related:
            w = self.w
            args['formid'] = 'deleteconf'
            args['action'] = 'delete'
            w(u'<div id="%s-delete" class="editableField" onclick="%s" title="%s">' %
              (divid, xml_escape(self._onclick % args), self._cw._(self._deletemsg)))
            w(self._build_delete_zone())
            w(u'</div>')

    def _close_form_wrapper(self):
        self.w(u'</div>')
        self.w(u'</div>')

    def view_form(self, divid, value, form=None, renderer=None,
                  edit_related=False, add_related=False, delete_related=False):
        self._open_form_wrapper(divid, value, form, renderer,
                                edit_related, add_related, delete_related)
        args = form.event_args.copy()
        self._edit_action(divid, args, edit_related, add_related, delete_related)
        self._add_action(divid, args, edit_related, add_related, delete_related)
        self._del_action(divid, args, edit_related, add_related, delete_related)
        self._close_form_wrapper()


@ajaxfunc(output_type='xhtml')
def reledit_form(self):
    req = self._cw
    args = dict((x, req.form[x])
                for x in ('formid', 'rtype', 'role', 'reload', 'action'))
    rset = req.eid_rset(int(self._cw.form['eid']))
    try:
        args['reload'] = json.loads(args['reload'])
    except ValueError: # not true/false, an absolute url
        assert args['reload'].startswith('http')
    view = req.vreg['views'].select('reledit', req, rset=rset, rtype=args['rtype'])
    return self._call_view(view, **args)