from wagtail.models import Locale, Page

from books.models.module import Module
from books.models.topic import Topic

from core.logger import get_logger

logger = get_logger(__name__)


# todo: make this a django command
# todo: add language to translate to as an argument
# todo: write a test maybe
def migrate_i18n(slug: str, original_slug: str):
    """
    Migrate a module and its children to a new locale and links it to
    its translation in the original locale.

    @param slug: the slug of the module to migrate
    @param original_slug: the slug of the module in the original locale
    """
    module = Module.objects.get(slug=slug)
    original = Module.objects.get(slug=original_slug)
    en = Locale.objects.get(language_code="en")
    logger.debug("starting this")
    topic: Topic = module.get_parent()
    try:
        logger.debug("getting translation")
        en_topic = topic.get_translation(en)
    except Page.DoesNotExist:
        logger.debug("creating translation")
        en_topic = topic.copy_for_translation(en)
        revision = en_topic.latest_revision
        en_topic.publish(revision)

    logger.debug(f"new topic {en_topic.pk}")
    module.locale = en
    if original is not None:
        translation_key = original.translation_key
        module.translation_key = translation_key
    module.save()
    chapters = module.get_children()
    for chapter in chapters:
        chapter.locale = en
        chapter.save()
        content_blocks = chapter.get_children()
        for content_block in content_blocks:
            content_block.locale = en
            content_block.save()

    module.move(en_topic, "last-child")

    print(f"go {module.title} {module.locale.language_code}")