import uuid
from datetime import datetime, timezone
from typing import Optional, TYPE_CHECKING
from sqlalchemy import String, DateTime, ForeignKey, Boolean, Integer
from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlalchemy.dialects.postgresql import UUID
from app.core.database import Base

if TYPE_CHECKING:
    from app.models.account import Account


class Subscription(Base):
    __tablename__ = "subscriptions"

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    account_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("accounts.id", ondelete="CASCADE"), unique=True, nullable=False)
    stripe_subscription_id: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    stripe_price_id: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    plan: Mapped[str] = mapped_column(String(50), nullable=False, default="free")
    billing_interval: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)
    status: Mapped[str] = mapped_column(String(50), nullable=False, default="active")
    seat_limit: Mapped[Optional[int]] = mapped_column(Integer, nullable=True)
    current_period_start: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    current_period_end: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    cancel_at_period_end: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=lambda: datetime.now(timezone.utc))
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=lambda: datetime.now(timezone.utc), onupdate=lambda: datetime.now(timezone.utc))

    # Relationships
    account: Mapped["Account"] = relationship("Account", back_populates="subscription")

    @property
    def is_active(self) -> bool:
        return self.status in ("active", "trialing", "complimentary")

    @property
    def is_paid(self) -> bool:
        # Excludes complimentary and trialing so MRR/paid-customer metrics aren't inflated.
        return self.plan in ("pro", "starter", "enterprise") and self.status not in ("complimentary", "trialing")

    @property
    def has_pro_entitlement(self) -> bool:
        """True if the account can access Pro features right now."""
        if self.plan in ("pro", "starter", "enterprise"):
            if self.status in ("active", "complimentary"):
                return True
        if self.status == "trialing" and self.current_period_end is not None:
            from datetime import datetime, timezone
            return self.current_period_end > datetime.now(timezone.utc)
        return False