#
# Copyright 2015 Quantopian, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import division

from copy import copy

from zipline.protocol import DATASOURCE_TYPE
from zipline.utils.serialization_utils import (
    VERSION_LABEL
)


class Transaction(object):

    def __init__(self, sid, amount, dt, price, order_id, commission=None):
        self.sid = sid
        self.amount = amount
        self.dt = dt
        self.price = price
        self.order_id = order_id
        self.commission = commission
        self.type = DATASOURCE_TYPE.TRANSACTION

    def __getitem__(self, name):
        return self.__dict__[name]

    def to_dict(self):
        py = copy(self.__dict__)
        del py['type']
        return py

    def __getstate__(self):

        state_dict = copy(self.__dict__)

        STATE_VERSION = 1
        state_dict[VERSION_LABEL] = STATE_VERSION

        return state_dict

    def __setstate__(self, state):

        OLDEST_SUPPORTED_STATE = 1
        version = state.pop(VERSION_LABEL)

        if version < OLDEST_SUPPORTED_STATE:
            raise BaseException("Transaction saved state is too old.")

        self.__dict__.update(state)


def create_transaction(event, order, price, amount):

    # floor the amount to protect against non-whole number orders
    # TODO: Investigate whether we can add a robust check in blotter
    # and/or tradesimulation, as well.
    amount_magnitude = int(abs(amount))

    if amount_magnitude < 1:
        raise Exception("Transaction magnitude must be at least 1.")

    transaction = Transaction(
        sid=event.sid,
        amount=int(amount),
        dt=event.dt,
        price=price,
        order_id=order.id
    )

    return transaction