#!/usr/bin/env python
# -*- coding:utf-8 -*-

# file:checkTable.py
# author:Itsuka
# datetime:2021年8月25日 9:53
# software: PyCharm

"""
 检验表是否符合生成规则
"""

import keyword

from utils.loggings import loggings
from utils.tablesMetadata import TableMetadata


class CheckTable(object):

 # check the Primary key
 # 检查table主键
 @classmethod
 def check_primary_key(cls, table_dict, session_id, ip):
 """
 根据代码生成模式,自动读取所有表或所需表,检验主键后返回合规的表列表
 :return: 符合规范的表名列表,即有且仅有一个主键,没有符合规范的情况下返回None
 """

 available_tables = []
 invalid_tables = []

 for table in table_dict.values():
 if table['is_view']:
 # 是一个视图,不进行检查
 continue
 elif len(table['primary_key_columns']) == 0:
 # 表中没有主键
 invalid_tables.append(table['table_name'])
 loggings.warning(1, 'table {0} do not have a primary key'.format(table['table_name']), session_id, ip)
 # elif len(table['primary_key_columns']) > 1:
 # # 表中有复数个主键
 # invalid_tables.append(table['table_name'])
 # loggings.warning(1, 'table {0} has multiple primary keys'.format(table['table_name']))
 else:
 available_tables.append(table['table_name'])

 return available_tables, invalid_tables

 # check keywords of python in tables
 # 检查表名和字段名,是否和Python的关键字冲突
 @classmethod
 def check_keyword_conflict(cls, table_dict, session_id, ip):
 """
 check whether the table name or column name is a keyword of python
 :return: True while no table name is a keyword, else return False
 """

 available_table = []
 invalid_table = []

 for table in table_dict.values():

 if table['is_view']:
 # 是一个视图,不进行检查
 continue

 flag = True

 # 检查表名是否为python关键字
 if keyword.iskeyword(table['table_name']):
 loggings.warning(1, 'table "{0}" is a keyword of python'.format(table['table_name']), session_id, ip)
 flag = False

 for column in table['columns'].values():
 # 检查表字段是否为python关键字
 if keyword.iskeyword(column['name']):
 loggings.warning(1, 'column "{0}.{1}" is a keyword of python'.format(table['table_name'],
 column['name']), session_id, ip)
 flag = False

 if flag:
 available_table.append(table['table_name'])
 else:
 invalid_table.append(table['table_name'])

 return available_table, invalid_table

 # 入口函数定义
 @classmethod
 def main(cls, metadata, reflection_views, session_id, ip):
 """
 建立数据库连接时对表进行检查,筛去没有唯一自增主键、表名/字段名与Python关键字有冲突的表
 :param metadata: 数据库元数据
 :param reflection_views: 需要反射的视图名称列表
 """

 table_dict = TableMetadata.get_tables_metadata(metadata, reflection_views)
 invalid_tables = {}

 # check table primary key
 available_table, invalid_table = cls.check_primary_key(table_dict, session_id, ip)
 invalid_tables['primary_key'] = invalid_table
 for invalid in invalid_table:
 table_dict.pop(invalid)

 # check the keyword
 available_table, invalid_table = cls.check_keyword_conflict(table_dict, session_id, ip)
 available_tables = available_table
 invalid_tables['keyword'] = invalid_table
 for invalid in invalid_table:
 table_dict.pop(invalid)

 if len(invalid_tables) > 0:
 loggings.warning(
 1,
 "A total of {0} tables check passed."
 "The following {1} tables do not meet the specifications and cannot be generated: {2}."
 .format(
 len(available_tables),
 len(invalid_tables['primary_key'] + invalid_tables['keyword']),
 ",".join(invalid_tables['primary_key'] + invalid_tables['keyword'])
 ),
 session_id,
 ip
 )

 return table_dict, invalid_tables

 loggings.info(1, "All table checks passed, a total of {0} tables.".format(len(available_tables)), session_id, ip)

 return table_dict, invalid_tables