from enum import Enum
from typing import TYPE_CHECKING, Optional

from sqlalchemy import Column, UniqueConstraint
from sqlalchemy import Enum as SAEnum
from sqlmodel import Field, Relationship, SQLModel

if TYPE_CHECKING:
    from app.models.route import Route


class MailEventType(str, Enum):
    ROUND_ANNOUNCED = "round_announced"
    ORDER_CONFIRMED = "order_confirmed"
    PAYMENT_CONFIRMED = "payment_confirmed"


class MailTemplateBase(SQLModel):
    event_type: MailEventType = Field(
        sa_column=Column(
            SAEnum(
                MailEventType,
                name="mail_event_type",
                native_enum=False,
                values_callable=lambda enum_cls: [member.value for member in enum_cls],
            ),
            nullable=False,
        ),
    )
    subject: str
    body_html: str


class MailTemplate(MailTemplateBase, table=True):
    __tablename__ = "mail_template"
    __table_args__ = (UniqueConstraint("route_id", "event_type", name="uq_mail_template_route_event"),)

    id: Optional[int] = Field(default=None, primary_key=True)
    route_id: int = Field(foreign_key="route.id", ondelete="CASCADE")

    route: "Route" = Relationship(back_populates="mail_templates")


class MailTemplateCreate(MailTemplateBase):
    route_id: int


class MailTemplateUpdate(SQLModel):
    subject: Optional[str] = None
    body_html: Optional[str] = None


class MailTemplatePublic(MailTemplateBase):
    id: int
    route_id: int