# -*- coding: utf-8 -*-
#########################################################################
#
# Copyright (C) 2016 OSGeo
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
#########################################################################

from django.contrib import admin
from django.contrib.auth.forms import AdminPasswordChangeForm
from django.utils.translation import ugettext, ugettext_lazy as _
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import csrf_protect
from django.db import transaction
from django.views.decorators.debug import sensitive_post_parameters
from django.contrib.admin.options import IS_POPUP_VAR
from django.shortcuts import get_object_or_404
from django.utils.html import escape
from django.template.response import TemplateResponse
from django.contrib import messages
from django.http import HttpResponseRedirect, Http404
from django.conf import settings
from django.core.exceptions import PermissionDenied

from .models import Profile
from .forms import ProfileCreationForm, ProfileChangeForm

import autocomplete_light

csrf_protect_m = method_decorator(csrf_protect)
sensitive_post_parameters_m = method_decorator(sensitive_post_parameters())


class ProfileAdmin(admin.ModelAdmin):
    list_display = ('id', 'username', 'organization',)
    search_fields = ('username', 'organization', 'profile', )
    autocomplete_light.modelform_factory(Profile, fields='__all__')
    add_form_template = 'admin/auth/user/add_form.html'
    change_user_password_template = None
    fieldsets = (
        (None, {'fields': ('username', 'password')}),
        (_('Personal info'), {'fields': ('first_name', 'last_name', 'email')}),
        (_('Permissions'), {'fields': ('is_active', 'is_staff', 'is_superuser',
                                       'groups')}),
        (_('Important dates'), {'fields': ('last_login', 'date_joined')}),
        (_('Extended profile'), {'fields': ('organization', 'profile',
                                            'position', 'voice', 'fax',
                                            'delivery', 'city', 'area',
                                            'zipcode', 'country',
                                            'keywords')}),
    )
    add_fieldsets = (
        (None, {
            'classes': ('wide',),
            'fields': ('username', 'password1', 'password2')}
         ),
    )
    form = ProfileChangeForm
    add_form = ProfileCreationForm
    change_password_form = AdminPasswordChangeForm
    list_display = ('username', 'email', 'first_name', 'last_name', 'is_staff')
    list_filter = ('is_staff', 'is_superuser', 'is_active', 'groups')
    search_fields = ('username', 'first_name', 'last_name', 'email')
    ordering = ('username',)
    filter_horizontal = ('groups', 'user_permissions',)

    def get_fieldsets(self, request, obj=None):
        if not obj:
            return self.add_fieldsets
        return super(ProfileAdmin, self).get_fieldsets(request, obj)

    def get_form(self, request, obj=None, **kwargs):
        """
        Use special form during user creation
        """
        defaults = {}
        if obj is None:
            defaults.update({
                'form': self.add_form,
                'fields': admin.utils.flatten_fieldsets(self.add_fieldsets),
            })
        defaults.update(kwargs)
        return super(ProfileAdmin, self).get_form(request, obj, **defaults)

    def get_urls(self):
        from django.conf.urls import patterns
        return patterns('',
                        (r'^(\d+)/password/$',
                         self.admin_site.admin_view(self.user_change_password))
                        ) + super(ProfileAdmin, self).get_urls()

    def lookup_allowed(self, lookup, value):
        # See #20078: we don't want to allow any lookups involving passwords.
        if lookup.startswith('password'):
            return False
        return super(ProfileAdmin, self).lookup_allowed(lookup, value)

    @sensitive_post_parameters_m
    @csrf_protect_m
    @transaction.atomic
    def add_view(self, request, form_url='', extra_context=None):
        # It's an error for a user to have add permission but NOT change
        # permission for users. If we allowed such users to add users, they
        # could create superusers, which would mean they would essentially have
        # the permission to change users. To avoid the problem entirely, we
        # disallow users from adding users if they don't have change
        # permission.
        if not self.has_change_permission(request):
            if self.has_add_permission(request) and settings.DEBUG:
                # Raise Http404 in debug mode so that the user gets a helpful
                # error message.
                raise Http404(
                    'Your user does not have the "Change user" permission. In '
                    'order to add users, Django requires that your user '
                    'account have both the "Add user" and "Change user" '
                    'permissions set.')
            raise PermissionDenied
        if extra_context is None:
            extra_context = {}
        username_field = self.model._meta.get_field(self.model.USERNAME_FIELD)
        defaults = {
            'auto_populated_fields': (),
            'username_help_text': username_field.help_text,
        }
        extra_context.update(defaults)
        return super(ProfileAdmin, self).add_view(request, form_url,
                                                  extra_context)

    @sensitive_post_parameters_m
    def user_change_password(self, request, id, form_url=''):
        if not self.has_change_permission(request):
            raise PermissionDenied
        user = get_object_or_404(self.get_queryset(request), pk=id)
        if request.method == 'POST':
            form = self.change_password_form(user, request.POST)
            if form.is_valid():
                form.save()
                change_message = self.construct_change_message(
                    request,
                    form,
                    None)
                self.log_change(request, user, change_message)
                msg = ugettext('Password changed successfully.')
                messages.success(request, msg)
                return HttpResponseRedirect('..')
        else:
            form = self.change_password_form(user)

        fieldsets = [(None, {'fields': list(form.base_fields)})]
        adminForm = admin.helpers.AdminForm(form, fieldsets, {})

        context = {
            'title': _('Change password: %s') % escape(user.get_username()),
            'adminForm': adminForm,
            'form_url': form_url,
            'form': form,
            'is_popup': IS_POPUP_VAR in request.REQUEST,
            'add': True,
            'change': False,
            'has_delete_permission': False,
            'has_change_permission': True,
            'has_absolute_url': False,
            'opts': self.model._meta,
            'original': user,
            'save_as': False,
            'show_save': True,
        }
        return TemplateResponse(request,
                                self.change_user_password_template or
                                'admin/auth/user/change_password.html',
                                context, current_app=self.admin_site.name)

    def response_add(self, request, obj, post_url_continue=None):
        """
        Determines the HttpResponse for the add_view stage. It mostly defers to
        its superclass implementation but is customized because the User model
        has a slightly different workflow.
        """
        # We should allow further modification of the user just added i.e. the
        # 'Save' button should behave like the 'Save and continue editing'
        # button except in two scenarios:
        # * The user has pressed the 'Save and add another' button
        # * We are adding a user in a popup
        if '_addanother' not in request.POST and IS_POPUP_VAR not in request.POST:
            request.POST['_continue'] = 1
        return super(ProfileAdmin, self).response_add(request, obj,
                                                      post_url_continue)


admin.site.register(Profile, ProfileAdmin)
