# 创建连接相关
from sqlalchemy import create_engine, text
from sqlalchemy.orm import sessionmaker
from urllib.parse import quote_plus as urlquote

from const import sparkatp_sql_uri

from logger import logger

_ENGINE_CACHE = {}


"""
sql操作：
排序：order_by(ChartsName.column.desc()/asc())
limit: .offset(n)过滤前面n条数据 .limit(n)
count: .count()计数
是否存在：is_exist = session.query(exists().where(Book.id > 10)).scalar()
or: .filter(or_(Chart.column == x, Chart.column > y)).all()
one: .one()只获取一条，如不存在或存在多条都会报错
first: 通过主键获取记录  filter(**).first()
"""


class SqlSession:
    def __init__(self, sql_uri=sparkatp_sql_uri):
        self.sql_uri = sql_uri
        self._session = self.get_session()

    @staticmethod
    def build_postgres_uri(host, port, user, password, database):
        return f"postgresql+psycopg2://{user}:{urlquote(str(password))}@{host}:{port}/{database}"

    def get_session(self):
        engine = _ENGINE_CACHE.get(self.sql_uri)
        if engine is None:
            engine = create_engine(
                self.sql_uri,
                pool_size=5,
                max_overflow=10,
                pool_pre_ping=True,
                pool_recycle=1800,
                pool_timeout=30,
                connect_args={
                    'connect_timeout': 20,
                    'options': '-c timezone=Asia/Shanghai'
                }
            )
            _ENGINE_CACHE[self.sql_uri] = engine
        Session = sessionmaker(bind=engine)
        session = Session()
        return session

    def query(self, obj):
        return self._session.query(obj)

    def add(self, added):
        self._session.add(added)

    def add_all(self, added_list):
        if isinstance(added_list, list):
            self._session.add_all(added_list)
        else:
            logger.warning('只能传递list')

    def flush(self):
        self._session.flush()

    def commit(self):
        self._session.commit()

    def close(self):
        self._session.close()

    def execute(self, sql):
        return self._session.execute(text(sql))

    def done(self, close=True):
        """
        执行完插入、删除、修改等操作后执行done，如报错回滚本次事务的sql操作
        :return:
        """
        try:
            self.commit()
            if close:
                self.close()
        except Exception as e:
            logger.warning(e)
            self._session.rollback()
            return e

    @property
    def session(self):
        return self._session


def to_dict(self):
    return {c.name: getattr(self, c.name, None) for c in self.__table__.columns}