"""
数据库初始化 + User 模型。
使用 SQLite（单文件），存放在 data/epeekit.db。
"""

import secrets
import uuid
from datetime import datetime
from pathlib import Path

from sqlmodel import Field, Session, SQLModel, create_engine, select

DATA_DIR = Path(__file__).parent.parent / "data"
DATA_DIR.mkdir(exist_ok=True)

DATABASE_URL = f"sqlite:///{DATA_DIR / 'epeekit.db'}"

engine = create_engine(DATABASE_URL, echo=False)


class User(SQLModel, table=True):
    id: str = Field(default_factory=lambda: uuid.uuid4().hex, primary_key=True)
    username: str = Field(index=True, unique=True)
    hashed_password: str
    display_name: str = ""
    is_admin: bool = False
    is_active: bool = True
    created_at: datetime = Field(default_factory=datetime.utcnow)


def create_db_and_tables():
    SQLModel.metadata.create_all(engine)


def get_session():
    with Session(engine) as session:
        yield session


def ensure_default_admin():
    """如果 users 表为空，创建默认管理员账号。"""
    import os
    from app.auth import hash_password

    with Session(engine) as session:
        user = session.exec(select(User).limit(1)).first()
        if user is not None:
            return

        password = os.getenv("ADMIN_DEFAULT_PASSWORD", "")
        if not password:
            password = secrets.token_urlsafe(12)
            print(f"\n{'='*50}")
            print(f"  默认管理员账号已创建")
            print(f"  用户名: admin")
            print(f"  密码:   {password}")
            print(f"  请登录后尽快修改密码！")
            print(f"{'='*50}\n")

        admin = User(
            username="admin",
            hashed_password=hash_password(password),
            display_name="管理员",
            is_admin=True,
        )
        session.add(admin)
        session.commit()