# -*- coding: utf-8 -*-
from django.db import migrations


def initial_data(apps, schema_editor):
    ContentType = apps.get_model('contenttypes.ContentType')
    Group = apps.get_model('auth.Group')
    Page = apps.get_model('wagtailcore.Page')
    Site = apps.get_model('wagtailcore.Site')
    GroupPagePermission = apps.get_model('wagtailcore.GroupPagePermission')

    # Create page content type
    page_content_type, created = ContentType.objects.get_or_create(
        model='page',
        app_label='wagtailcore'
    )

    # Create root page
    root = Page.objects.create(
        title="Root",
        slug='root',
        content_type=page_content_type,
        path='0001',
        depth=1,
        numchild=1,
        url_path='/',
    )

    # Create homepage
    homepage = Page.objects.create(
        title="Welcome to your new Wagtail site!",
        slug='home',
        content_type=page_content_type,
        path='00010001',
        depth=2,
        numchild=0,
        url_path='/home/',
    )

    # Create default site
    Site.objects.create(
        hostname='localhost',
        root_page_id=homepage.id,
        is_default_site=True
    )

    # Create auth groups
    moderators_group = Group.objects.create(name='Moderators')
    editors_group = Group.objects.create(name='Editors')

    # Create group permissions
    GroupPagePermission.objects.create(
        group=moderators_group,
        page=root,
        permission_type='add',
    )
    GroupPagePermission.objects.create(
        group=moderators_group,
        page=root,
        permission_type='edit',
    )
    GroupPagePermission.objects.create(
        group=moderators_group,
        page=root,
        permission_type='publish',
    )

    GroupPagePermission.objects.create(
        group=editors_group,
        page=root,
        permission_type='add',
    )
    GroupPagePermission.objects.create(
        group=editors_group,
        page=root,
        permission_type='edit',
    )


def remove_initial_data(apps, schema_editor):
    """This function does nothing. The below code is commented out together
    with an explanation of why we don't need to bother reversing any of the
    initial data"""
    pass
    # This does not need to be deleted, Django takes care of it.
    # page_content_type = ContentType.objects.get(
    #     model='page',
    #     app_label='wagtailcore',
    # )

    # Page objects: Do nothing, the table will be deleted when reversing 0001

    # Do not reverse Site creation since other models might depend on it

    # Remove auth groups -- is this safe? External objects might depend
    # on these groups... seems unsafe.
    # Group.objects.filter(
    #     name__in=('Moderators', 'Editors')
    # ).delete()
    #
    # Likewise, we're leaving all GroupPagePermission unchanged as users may
    # have been assigned such permissions and its harmless to leave them.


class Migration(migrations.Migration):

    dependencies = [
        ('wagtailcore', '0001_initial'),
    ]

    operations = [
        migrations.RunPython(initial_data, remove_initial_data),
    ]