from typing import List, Optional, TYPE_CHECKING
if TYPE_CHECKING:
    from .rooms import Room

from sqlalchemy import Identity, Integer, Unicode
from sqlalchemy.orm import Mapped, mapped_column, relationship

from . import db
from ..temp import is_temp_id
from ..utils.validation import ValidatableMixin

class RoomFunction(ValidatableMixin, db.Model):
    __tablename__ = 'Room Functions'
    VALIDATION_LABEL = "Function"

    id: Mapped[int] = mapped_column("ID", Integer, Identity(start=1, increment=1), primary_key=True)
    description: Mapped[Optional[str]] = mapped_column("Function", Unicode(255), nullable=True)

    rooms: Mapped[List['Room']] = relationship('Room', back_populates='room_function')

    def __init__(self, description: Optional[str] = None):
        self.description = description

    def __repr__(self):
        return f"<RoomFunction(id={self.id}, description={repr(self.description)})>"
    
    def serialize(self):
        return {
            'id': self.id,
            'name': self.description
        }
    
    @classmethod
    def sync_from_state(cls, submitted_items: list[dict]) -> dict[str, int]:
        submitted_clean = []
        seen_ids = set()
        temp_id_map = {}

        for item in submitted_items:
            if not isinstance(item, dict):
                continue
            name = str(item.get("name", "")).strip()
            raw_id = item.get("id")

            if not name:
                continue

            try:
                if raw_id:
                    parsed_id = int(raw_id)
                    if parsed_id >= 0:
                        seen_ids.add(parsed_id)
            except (ValueError, TypeError):
                pass

            submitted_clean.append({"id": raw_id, "description": name})

        existing_by_id = {f.id: f for f in db.session.query(cls).all()}
        existing_ids = set(existing_by_id.keys())

        print(f"Existing function IDs: {existing_ids}")
        print(f"Submitted function IDs: {seen_ids}")

        for entry in submitted_clean:
            submitted_id = entry.get("id")
            description = entry["description"]

            if is_temp_id(submitted_id):
                obj = cls(description=description)
                db.session.add(obj)
                db.session.flush()
                temp_id_map[submitted_id] = obj.id
                print(f"➕ Adding function: {description}")
            elif isinstance(submitted_id, int) or submitted_id.isdigit():
                submitted_id_int = int(submitted_id)
                obj = existing_by_id.get(submitted_id_int)
                if obj and obj.description != description:
                    print(f"✏️ Updating function {obj.id}: '{obj.description}' → '{description}'")
                    obj.description = description

        for id_to_remove in existing_ids - seen_ids:
            obj = existing_by_id[id_to_remove]
            db.session.delete(obj)
            print(f"🗑️ Removing function ID {id_to_remove}")

        id_map = {
            **{str(i): i for i in seen_ids},
            **{str(temp): real for temp, real in temp_id_map.items()}
        }
        return id_map