from abc import ABC, abstractmethod

from bson import ObjectId
from pydantic import BaseModel, Field

__all__ = ["PyObjectId", "MongoBase", "MongoCollection"]


class PyObjectId(ObjectId):
    """Custom type for bson ObjectIds"""

    @classmethod
    def __get_validators__(cls):
        yield cls.validate

    @classmethod
    def validate(cls, value: str):
        """Check that a string is a valid bson ObjectId"""
        if not ObjectId.is_valid(value):
            raise ValueError(f"Invalid ObjectId: '{value}'")

        return ObjectId(value)

    @classmethod
    def __modify_schema__(cls, field_schema: dict):
        field_schema.update(type="string")


class MongoBase(BaseModel):
    """Base model that properly sets the _id field, and adds one by default"""

    id: PyObjectId = Field(default_factory=PyObjectId, alias="_id")

    class Config:
        """Configuration for encoding and construction"""

        allow_population_by_field_name = True
        arbitrary_types_allowed = True
        json_encoders = {ObjectId: str, PyObjectId: str}
        use_enum_values = True


class MongoCollection(MongoBase, ABC):
    """Base model for the 'main class' in a collection

    This field stores the name of the collection to avoid making typos against it
    """

    @staticmethod
    @abstractmethod
    def collection() -> str:
        """Getter for the name of the collection, in order to avoid typos"""
        raise NotImplementedError