# -*- coding: utf-8 -*-
"""
    utils.List2Json
    ~~~~~~~~~~~~~~

    Sql_alchemy的实体转json.

    :copyright: 云南新八达科技有限公司.
    :author: 李进才.
"""
import decimal
import types
from datetime import datetime

from flask import json
from sqlalchemy.ext.declarative import DeclarativeMeta


class AlchemyEncoder(json.JSONEncoder):

    def default(self, obj):
        if isinstance(obj.__class__, DeclarativeMeta):
            # an SQLAlchemy class
            fields = {}
            for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']:
                data = obj.__getattribute__(field)
                if field == 'query' or field == 'query_class':
                    continue
                try:
                    # json.dumps(data, ensure_ascii=False)   this will fail on non-encodable values, like other classes
                    if str(data) == 'None':
                        data = ''
                    if isinstance(data, types.GeneratorType):
                        data
                    fields[field] = str(data)
                    if isinstance(data, bool) or isinstance(data, int):
                        fields[field] = data
                    if isinstance(data, decimal.Decimal):
                        return (str(data) for data in [data])
                except TypeError:
                    fields[field] = None
            # a json-encodable dict
            return fields

        return json.JSONEncoder.default(self, obj)


class DecimalEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, decimal.Decimal):
            return float(obj)
        if isinstance(obj, datetime):
            return str(obj)
        return super(DecimalEncoder, self).default(obj)