import json
from datetime import datetime, timezone

from sqlalchemy import DateTime, ForeignKey, String, Text
from sqlalchemy.orm import Mapped, mapped_column, relationship

from .database import Base


def utcnow() -> datetime:
    return datetime.now(timezone.utc)


class User(Base):
    __tablename__ = "users"

    id: Mapped[int] = mapped_column(primary_key=True)
    email: Mapped[str] = mapped_column(String(255), unique=True, index=True)
    password_hash: Mapped[str] = mapped_column(String(255))
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utcnow)

    links: Mapped[list["Link"]] = relationship(
        back_populates="user", cascade="all, delete-orphan"
    )


class Link(Base):
    __tablename__ = "links"

    id: Mapped[int] = mapped_column(primary_key=True)
    user_id: Mapped[int] = mapped_column(ForeignKey("users.id"), index=True)
    url: Mapped[str] = mapped_column(Text)
    title: Mapped[str] = mapped_column(Text, default="")
    summary: Mapped[str] = mapped_column(Text, default="")
    category: Mapped[str] = mapped_column(String(120), default="", index=True)
    manufacturer: Mapped[str] = mapped_column(String(120), default="", index=True)
    tags: Mapped[str] = mapped_column(Text, default="[]")  # JSON-Liste
    embedding: Mapped[str] = mapped_column(Text, default="")  # JSON-Liste (Vektor)
    status: Mapped[str] = mapped_column(String(20), default="ok")
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utcnow, index=True)

    user: Mapped["User"] = relationship(back_populates="links")

    @property
    def tag_list(self) -> list[str]:
        try:
            return json.loads(self.tags)
        except (ValueError, TypeError):
            return []