import enum
import uuid
from datetime import datetime

from sqlalchemy import DateTime, Enum, Float, ForeignKey, Integer, String, Text, func
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.database import Base


def _uuid() -> str:
    return str(uuid.uuid4())


def _now() -> datetime:
    return datetime.utcnow()


class TenantStatus(str, enum.Enum):
    active = "active"
    suspended = "suspended"
    deleted = "deleted"


class Tenant(Base):
    __tablename__ = "tenants"

    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=_uuid)
    name: Mapped[str] = mapped_column(String(200), nullable=False)
    slug: Mapped[str] = mapped_column(String(100), unique=True, nullable=False)
    status: Mapped[TenantStatus] = mapped_column(
        Enum(TenantStatus), default=TenantStatus.active
    )
    created_at: Mapped[datetime] = mapped_column(DateTime, default=_now)
    updated_at: Mapped[datetime] = mapped_column(DateTime, default=_now, onupdate=_now)

    config: Mapped["TenantConfig | None"] = relationship(back_populates="tenant", uselist=False)


class TenantConfig(Base):
    __tablename__ = "tenant_configs"

    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=_uuid)
    tenant_id: Mapped[str] = mapped_column(
        String(36), ForeignKey("tenants.id"), unique=True, nullable=False
    )
    llm_provider: Mapped[str] = mapped_column(String(50), nullable=False)
    llm_api_key: Mapped[str] = mapped_column(Text, nullable=False)
    llm_model: Mapped[str] = mapped_column(String(100), nullable=False)
    llm_base_url: Mapped[str | None] = mapped_column(String(500), nullable=True)
    max_tokens_per_month: Mapped[int] = mapped_column(Integer, default=1000000)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=_now)
    updated_at: Mapped[datetime] = mapped_column(DateTime, default=_now, onupdate=_now)

    tenant: Mapped["Tenant"] = relationship(back_populates="config")