from sqlalchemy import exists, Column, Integer, String, ForeignKey, exists
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

# 創建的數據庫引擎
engine = create_engine("mysql+pymysql://user:pwd@ip/數據庫名?charset=utf8")

#創建session類型
DBSession = sessionmaker(bind=engine)

# 實例化官宣模型 - Base 就是 ORM 模型
Base = declarative_base()


# 創建服務單表
class ServiceOrder(Base):
  __tablename__ = 'serviceOrderTable'
  id = Column(Integer, primary_key=True, autoincrement=True)
  serviceOrderId = Column(String(32), nullable=False, index=True, comment='服務單ID')
  serviceDesc = Column(String(268), comment='服務說明')
  oneLevelName = Column(String(32), comment='C類別')
  twoLevelName = Column(String(32), comment='T子類')
  threeLevelName = Column(String(32), comment='I項目')
  fourLevelName = Column(String(32), comment='S子項')
  transferTimes = Column(String(32), comment='轉派次數')
  overDueStatus = Column(String(32), comment='過期狀態')
  serviceTimeLimit = Column(String(32), comment='服務時限')
  serTimeLimitTypeName = Column(String(16), comment='時限類型')  
  # 一對多:
  # serviceWorkOrder = relationship("ServiceWorkOrder", backref="serviceorder")


# 多對一:多個服務工單可以屬于服務單
class ServiceWorkOrder(Base):
  __tablename__ = 'serviceWorkOrderTable'
  id = Column(Integer, primary_key=True, autoincrement=True)
  serviceWorkOrderId = Column(String(32), nullable=False, index=True, comment='服務工單ID')
  workOrderName = Column(String(268), comment='工單名稱')
  fromId = Column(String(32), comment='服務單ID')
  createUserSectionName = Column(String(32), comment='創建人室')
  createUserName = Column(String(32), comment='創建人')
  handlerName = Column(String(32), comment='處理人')
  statusName = Column(String(32), comment='工單狀態')
  createTime = Column(String(32), comment='創建時間') 
  # “多”的一方的book表是通過外鍵關聯到user表的:
  # serviceOrder_id = Column(Integer, ForeignKey('serviceOrderTable.id'))

# 創建數據庫 如果數據庫已存在 則不會創建 會根據庫名直接連接已有的庫
def init_db():
  Base.metadata.create_all(engine)

def drop_db():
  Base.metadata.drop_all(engine)

def insert_update():
  # all_needed_data_lists 是需要插入數據庫的數據 格式[{key: value, ... }, { }, { }...]
  for item in all_needed_data_lists:
    ServiceOrderRow = ServiceOrder(serviceOrderId=item['serviceOrderId'],
                    serviceDesc=item['serviceDesc'],
                    oneLevelName=item['oneLevelName'],
                    twoLevelName=item['twoLevelName'],
                    threeLevelName=item['threeLevelName'],
                    fourLevelName=item['fourLevelName'],
                    transferTimes=item['transferTimes'],
                    overDueStatus=item['overDueStatus'],
                    serviceTimeLimit=item['serviceTimeLimit'],
                    serTimeLimitTypeName=item['serTimeLimitTypeName'],
                    )
    try:
      # 利用exists判斷目標對象是否存在，返回True或Faults
      it_exists = session.query(
          exists().where(ServiceOrder.serviceOrderId == item['serviceOrderId'] )
        ).scalar()
    except Exception as e:
      self.log.error(e)
      break
    try:
      # 如果不存在，進行新增；存在的話就更新現存的數據
      if not it_exists:
        session.add(ServiceOrderRow)
      else:
        session.query(ServiceOrder).filter(ServiceOrder.serviceOrderId == item['serviceOrderId'])\
          .update(item)
    except Exception as e:
      self.log.error(e)
      break
  try:
    session.commit()
    self.log.info('數據更新成功！')
  except:
    session.rollback()
    self.log.info('數據更新失敗！')

if __name__ == "__main__":
  # 創建數據庫 如果數據庫已存在 則不會創建 會根據庫名直接連接已有的庫
  init_db()
  # 創建session對象，進行增刪改查:
  session = DBSession()
  # 利用session 增 改數據 記得提交
  insert_update()