from __future__ import annotations

from datetime import datetime
from typing import Optional

from sqlalchemy import Boolean, DateTime, ForeignKey, Integer, JSON, String, Text, func
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, relationship


class Base(DeclarativeBase):
    """Shared SQLAlchemy declarative base for app models and Alembic metadata."""


class Topic(Base):
    __tablename__ = "topics"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    name: Mapped[str] = mapped_column(String(120), nullable=False, unique=True)
    description: Mapped[str] = mapped_column(Text, nullable=False)
    enabled: Mapped[bool] = mapped_column(Boolean, nullable=False, default=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), nullable=False)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime, server_default=func.now(), onupdate=func.now(), nullable=False
    )


class AgentRun(Base):
    __tablename__ = "agent_runs"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    status: Mapped[str] = mapped_column(String(32), nullable=False)
    started_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), nullable=False)
    finished_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
    error: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
    request_payload: Mapped[dict] = mapped_column(JSON, nullable=False)
    raw_response: Mapped[Optional[dict]] = mapped_column(JSON, nullable=True)

    signals: Mapped[list["Signal"]] = relationship(back_populates="run")
    report: Mapped[Optional[Report]] = relationship(back_populates="run", uselist=False)


class Signal(Base):
    __tablename__ = "signals"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    run_id: Mapped[int] = mapped_column(ForeignKey("agent_runs.id"), nullable=False, index=True)
    source_type: Mapped[str] = mapped_column(String(20), nullable=False, default="news", index=True)
    topic: Mapped[str] = mapped_column(String(120), nullable=False, index=True)
    title: Mapped[str] = mapped_column(String(300), nullable=False)
    summary: Mapped[str] = mapped_column(Text, nullable=False)
    source_url: Mapped[str] = mapped_column(Text, nullable=False)
    source_url_hash: Mapped[str] = mapped_column(String(64), nullable=False, unique=True)
    source_name: Mapped[str] = mapped_column(String(200), nullable=False)
    published_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
    importance: Mapped[int] = mapped_column(Integer, nullable=False)
    entities: Mapped[list[str]] = mapped_column(JSON, nullable=False, default=list)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), nullable=False)

    run: Mapped[AgentRun] = relationship(back_populates="signals")


class Report(Base):
    __tablename__ = "reports"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    run_id: Mapped[int] = mapped_column(ForeignKey("agent_runs.id"), nullable=False)
    title: Mapped[str] = mapped_column(String(200), nullable=False)
    content_md: Mapped[str] = mapped_column(Text, nullable=False)
    file_path: Mapped[Optional[str]] = mapped_column(String(1024), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), nullable=False)

    run: Mapped[AgentRun] = relationship(back_populates="report")