from django.contrib.auth.models import User, Group
from django.core.exceptions import PermissionDenied
from django import template
from django.shortcuts import render_to_response, get_object_or_404
from django.template import RequestContext
from django.utils.html import escape
from django.http import HttpResponseRedirect
from django.utils.translation import ugettext, ugettext_lazy as _
from django.contrib.auth.forms import UserCreationForm, UserChangeForm, AdminPasswordChangeForm
from django.contrib import admin

class GroupAdmin(admin.ModelAdmin):
    search_fields = ('name',)
    ordering = ('name',)
    filter_horizontal = ('permissions',)

class UserAdmin(admin.ModelAdmin):
    fieldsets = (
        (None, {'fields': ('username', 'password')}),
        (_('Personal info'), {'fields': ('first_name', 'last_name', 'email')}),
        (_('Permissions'), {'fields': ('is_staff', 'is_active', 'is_superuser', 'user_permissions')}),
        (_('Important dates'), {'fields': ('last_login', 'date_joined')}),
        (_('Groups'), {'fields': ('groups',)}),
    )
    form = UserChangeForm
    add_form = UserCreationForm
    change_password_form = AdminPasswordChangeForm
    list_display = ('username', 'email', 'first_name', 'last_name', 'is_staff')
    list_filter = ('is_staff', 'is_superuser')
    search_fields = ('username', 'first_name', 'last_name', 'email')
    ordering = ('username',)
    filter_horizontal = ('user_permissions',)

    def __call__(self, request, url):
        # this should not be here, but must be due to the way __call__ routes
        # in ModelAdmin.
        if url is None:
            return self.changelist_view(request)
        if url.endswith('password'):
            return self.user_change_password(request, url.split('/')[0])
        return super(UserAdmin, self).__call__(request, url)

    def add_view(self, request):
        if not self.has_change_permission(request):
            raise PermissionDenied
        if request.method == 'POST':
            form = self.add_form(request.POST)
            if form.is_valid():
                new_user = form.save()
                msg = _('The %(name)s "%(obj)s" was added successfully.') % {'name': 'user', 'obj': new_user}
                self.log_addition(request, new_user)
                if "_addanother" in request.POST:
                    request.user.message_set.create(message=msg)
                    return HttpResponseRedirect(request.path)
                else:
                    request.user.message_set.create(message=msg + ' ' + ugettext("You may edit it again below."))
                    return HttpResponseRedirect('../%s/' % new_user.id)
        else:
            form = self.add_form()
        return render_to_response('admin/auth/user/add_form.html', {
            'title': _('Add user'),
            'form': form,
            'is_popup': '_popup' in request.REQUEST,
            'add': True,
            'change': False,
            'has_add_permission': True,
            'has_delete_permission': False,
            'has_change_permission': True,
            'has_file_field': False,
            'has_absolute_url': False,
            'auto_populated_fields': (),
            'opts': self.model._meta,
            'save_as': False,
            'username_help_text': self.model._meta.get_field('username').help_text,
            'root_path': self.admin_site.root_path,
            'app_label': self.model._meta.app_label,            
        }, context_instance=template.RequestContext(request))

    def user_change_password(self, request, id):
        if not request.user.has_perm('auth.change_user'):
            raise PermissionDenied
        user = get_object_or_404(self.model, pk=id)
        if request.method == 'POST':
            form = self.change_password_form(user, request.POST)
            if form.is_valid():
                new_user = form.save()
                msg = ugettext('Password changed successfully.')
                request.user.message_set.create(message=msg)
                return HttpResponseRedirect('..')
        else:
            form = self.change_password_form(user)
        return render_to_response('admin/auth/user/change_password.html', {
            'title': _('Change password: %s') % escape(user.username),
            'form': form,
            'is_popup': '_popup' 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,
            'root_path': self.admin_site.root_path,
        }, context_instance=RequestContext(request))


admin.site.register(Group, GroupAdmin)
admin.site.register(User, UserAdmin)