from datetime import datetime, timedelta
from typing import Set
from backend.content.models import DocumentDoc
from backend.content.models import ContentFolderDoc
from backend.document.document_manager import DocumentManager


class DocumentCleaner:
    @staticmethod
    async def clean_up_unused_documents():
        """
        Remove unused DocumentDoc records after all content_directories are updated.
        """

        # Collect all valid document IDs from all content folders
        valid_document_ids: Set[str] = set()
        async for folder in ContentFolderDoc.find():
            for directory in folder.content_directories:
                valid_document_ids.update(
                    filter(
                        None,
                        [
                            directory.cover_document_id,
                            directory.summary_text_new,
                            directory.title_text_new,
                            directory.content_html_new,
                            directory.content_text_new,
                            directory.content_document_id,
                        ],
                    )
                )

        print(
            f"Valid document IDs (from updated content directories): {valid_document_ids}"
        )
        # Calculate the time 1 day ago
        time_1_day_ago = datetime.now(datetime.UTC) - timedelta(days=1)

        # Retrieve all document IDs from DocumentDoc
        all_document_ids = set()
        async for doc in DocumentDoc.find(
            {
                "created_by": {"$regex": "^content-service-"},
                "create_time": {"$lt": time_1_day_ago},
            }
        ):  # Fetch all documents that are created by content-service
            if doc.document_id:  # Ensure document_id is not None
                all_document_ids.add(doc.document_id)
        print(f"All document IDs (from DocumentDoc): {all_document_ids}")

        # Find unused document IDs
        unused_document_ids = all_document_ids - valid_document_ids
        print(f"Unused document IDs: {unused_document_ids}")

        # Remove unused DocumentDoc records
        if unused_document_ids:
            document_manager = DocumentManager()
            await document_manager.delete_documents(unused_document_ids)
        else:
            print("No unused DocumentDocs to clean up.")