"""SQLAlchemy ORM models for sessions, messages, tool_runs, skill_prefs."""
from __future__ import annotations

from datetime import datetime, timezone

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

from app.storage.db import Base


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


class Session(Base):
    __tablename__ = "sessions"

    id: Mapped[str] = mapped_column(String(64), primary_key=True)
    user_id: Mapped[str] = mapped_column(String(64), default="default", index=True)
    title: Mapped[str] = mapped_column(String(255), default="新对话")
    created_at: Mapped[datetime] = mapped_column(default=_utcnow)
    updated_at: Mapped[datetime] = mapped_column(default=_utcnow, onupdate=_utcnow)

    messages: Mapped[list["Message"]] = relationship(
        back_populates="session", cascade="all, delete-orphan", order_by="Message.created_at"
    )


class Message(Base):
    __tablename__ = "messages"

    id: Mapped[str] = mapped_column(String(64), primary_key=True)
    session_id: Mapped[str] = mapped_column(
        String(64), ForeignKey("sessions.id", ondelete="CASCADE"), index=True
    )
    role: Mapped[str] = mapped_column(String(16))  # user/assistant/system/tool
    content: Mapped[str] = mapped_column(Text, default="")
    tool_calls_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    tool_call_id: Mapped[str | None] = mapped_column(String(64), nullable=True)
    thinking_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    created_at: Mapped[datetime] = mapped_column(default=_utcnow, index=True)

    session: Mapped[Session] = relationship(back_populates="messages")


class ToolRun(Base):
    __tablename__ = "tool_runs"

    id: Mapped[str] = mapped_column(String(64), primary_key=True)
    message_id: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
    session_id: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
    skill_name: Mapped[str] = mapped_column(String(64), index=True)
    args_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    result_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    ok: Mapped[int] = mapped_column(Integer, default=1)
    duration_ms: Mapped[int] = mapped_column(Integer, default=0)
    trace_id: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
    created_at: Mapped[datetime] = mapped_column(default=_utcnow)


class SkillPref(Base):
    __tablename__ = "skill_prefs"

    user_id: Mapped[str] = mapped_column(String(64), primary_key=True)
    skill_name: Mapped[str] = mapped_column(String(64), primary_key=True)
    enabled: Mapped[int] = mapped_column(Integer, default=1)
    config_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    updated_at: Mapped[datetime] = mapped_column(default=_utcnow, onupdate=_utcnow)