from datetime import datetime

from sqlalchemy import create_engine, event, text
from sqlalchemy.dialects.mysql import BIGINT
from sqlmodel import SQLModel, Field

from ..config import AppConfig
from ..config.config import AppCtx


def get_timestamp():
    return int(datetime.now().timestamp())


class BaseModel(SQLModel):
    """数据库基类"""

    id: int = Field(default=None, primary_key=True, sa_type=BIGINT(unsigned=True))
    created_at: int = Field(default_factory=get_timestamp, sa_type=BIGINT(unsigned=True))
    updated_at: int = Field(default_factory=get_timestamp, sa_type=BIGINT(unsigned=True))


@event.listens_for(BaseModel, "before_update")
def update_updated_at(mapper, connection, target):
    """更新数据库记录的时候，自动更新 updated_at 字段"""
    target.updated_at = get_timestamp()


def connect_db(config: AppConfig):
    """连接数据库"""

    # 导入所有模型，为了自动创建数据表

    dsn = f"mysql+pymysql://{config.database.user}:{config.database.password}@{config.database.host}:{config.database.port}/{config.database.database}"
    engine = create_engine(dsn, echo=config.debug)

    SQLModel.metadata.create_all(engine)
    AppCtx.g_db_engine = engine

    return engine


def create_database(config: AppConfig):
    """如果数据库不存在，就调用这个函数初始化数据库"""

    # 先创建一个没有指定数据库的连接
    dsn = f"mysql+pymysql://{config.database.user}:{config.database.password}@{config.database.host}:{config.database.port}"
    engine = create_engine(dsn, echo=config.debug)

    with engine.connect() as conn:
        conn.execute(
            text(
                f"CREATE DATABASE IF NOT EXISTS {config.database.database} CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci"
            )
        )
        conn.commit()