from datetime import UTC, datetime
from uuid import UUID, uuid4

from sqlalchemy import Boolean, DateTime, Integer, String, Uuid
from sqlalchemy.orm import Mapped, mapped_column

from app.db.base import Base


def _utcnow() -> datetime:
    return datetime.now(UTC)


class User(Base):
    __tablename__ = "users"

    id: Mapped[UUID] = mapped_column(Uuid, primary_key=True, default=uuid4)
    email: Mapped[str] = mapped_column(String(255), unique=True, index=True, nullable=False)
    hashed_password: Mapped[str] = mapped_column(String(255), nullable=False)
    is_verified: Mapped[bool] = mapped_column(Boolean, default=False, nullable=False)

    # Nullable so users who registered before names were required keep working.
    # New registrations require them at the schema layer.
    first_name: Mapped[str | None] = mapped_column(String(100), nullable=True)
    last_name: Mapped[str | None] = mapped_column(String(100), nullable=True)

    # Codes are stored bcrypt-hashed; cleared on use or supersede.
    verification_code_hash: Mapped[str | None] = mapped_column(String(255), nullable=True)
    verification_code_expires_at: Mapped[datetime | None] = mapped_column(
        DateTime(timezone=True), nullable=True
    )
    password_reset_code_hash: Mapped[str | None] = mapped_column(String(255), nullable=True)
    password_reset_code_expires_at: Mapped[datetime | None] = mapped_column(
        DateTime(timezone=True), nullable=True
    )

    # Chat preferences (Settings page). rag_mode: "strict" | "regular".
    rag_mode: Mapped[str] = mapped_column(
        String(16), default="strict", server_default="strict", nullable=False
    )
    web_max_results: Mapped[int] = mapped_column(
        Integer, default=5, server_default="5", nullable=False
    )
    # Answer-model preference. NULL = use the app-wide default
    # (settings.groq_reasoning_model). Value must be an id in
    # app.agents.models.CHAT_MODELS at the API layer.
    chat_model: Mapped[str | None] = mapped_column(String(64), nullable=True)

    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=_utcnow, nullable=False
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        default=_utcnow,
        onupdate=_utcnow,
        nullable=False,
    )