import logging

from django.db.models.signals import post_save
from django.dispatch import receiver
from django.utils.text import slugify

from .models import Project, ProjectUserAccess

logger = logging.getLogger(__name__)


def ensure_project_document_folder(project):
    """
    Create (or retrieve) a DocumentFolder for the given project and attach it
    as the default folder.  Safe to call multiple times (idempotent).

    Folder name  : "<code> – <name[:60]>"    e.g. "P00001 – Schuman"
    Folder slug  : "project-<code.lower()>-<slugify(name)[:80]>"
    Parent folder: the predefined folder with slug='projects'
    """
    from django.contrib.contenttypes.models import ContentType

    from documents.models import DocumentFolder, DocumentFolderAttachment

    parent = DocumentFolder.objects.filter(slug="projects", is_predefined=True).first()

    folder_name = f"{project.code} \u2013 {project.name[:60]}"
    folder_slug = f"project-{project.code.lower()}-{slugify(project.name)[:80]}"

    folder, _ = DocumentFolder.objects.get_or_create(
        slug=folder_slug,
        defaults={
            "name": folder_name,
            "application_label": "projects",
        },
    )

    if parent:
        folder.parent_folders.add(parent)

    ct = ContentType.objects.get_for_model(project)
    DocumentFolderAttachment.objects.get_or_create(
        folder=folder,
        content_type=ct,
        object_id=project.pk,
        defaults={"is_default": True},
    )

    return folder


@receiver(post_save, sender=Project)
def add_owner_as_project_user_access(sender, instance, created, **kwargs):
    if created:
        ProjectUserAccess.objects.get_or_create(
            project=instance,
            user=instance.created_by,
            defaults={'can_view': True, 'can_edit': True},
        )


@receiver(post_save, sender=Project)
def create_project_document_folder(sender, instance, created, **kwargs):
    if not created:
        return
    try:
        ensure_project_document_folder(instance)
    except Exception:
        logger.exception("Failed to create document folder for project %s", instance.pk)