#!/usr/bin/env python
#
# Copyright 2013 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 unittest import TestCase
from nose.tools import (
    timed,
    nottest
)

from datetime import datetime

import pytz
from zipline.finance import trading
from zipline.algorithm import TradingAlgorithm
from zipline.finance import slippage
from zipline.utils import factory
from zipline.utils.test_utils import (
    setup_logger,
    teardown_logger
)

DEFAULT_TIMEOUT = 15  # seconds
EXTENDED_TIMEOUT = 90


class RecordDateSlippage(slippage.FixedSlippage):
    def __init__(self, spread):
        super(RecordDateSlippage, self).__init__(spread=spread)
        self.latest_date = None

    def simulate(self, event, open_orders):
        self.latest_date = event['datetime']
        result = super(RecordDateSlippage, self).simulate(event, open_orders)
        return result


class TestAlgo(TradingAlgorithm):

    def __init__(self, asserter, *args, **kwargs):
        super(TestAlgo, self).__init__(*args, **kwargs)
        self.asserter = asserter

    def initialize(self, window_length=100):
        self.latest_date = None

        self.set_slippage(RecordDateSlippage(spread=0.05))
        self.stocks = [8229]
        self.ordered = False

    def handle_data(self, data):
        self.latest_date = self.get_datetime()

        if not self.ordered:
            for stock in self.stocks:
                self.order(stock, 100)

            self.ordered = True

        else:

            self.asserter.assertGreaterEqual(
                self.latest_date,
                self.slippage.latest_date
            )


class AlgorithmGeneratorTestCase(TestCase):
    def setUp(self):
        setup_logger(self)

    def tearDown(self):
        teardown_logger(self)

    @nottest
    def test_lse_algorithm(self):

        lse = trading.TradingEnvironment(
            bm_symbol='^FTSE',
            exchange_tz='Europe/London'
        )

        with lse:

            sim_params = factory.create_simulation_parameters(
                start=datetime(2012, 5, 1, tzinfo=pytz.utc),
                end=datetime(2012, 6, 30, tzinfo=pytz.utc)
            )
            algo = TestAlgo(self, sim_params=sim_params)
            trade_source = factory.create_daily_trade_source(
                [8229],
                200,
                sim_params
            )
            algo.set_sources([trade_source])

            gen = algo.get_generator()
            results = list(gen)
            self.assertEqual(len(results), 42)
            # May 7, 2012 was an LSE holiday, confirm the 4th trading
            # day was May 8.
            self.assertEqual(results[4]['daily_perf']['period_open'],
                             datetime(2012, 5, 8, 8, 31, tzinfo=pytz.utc))

    @timed(DEFAULT_TIMEOUT)
    def test_generator_dates(self):
        """
        Ensure the pipeline of generators are in sync, at least as far as
        their current dates.
        """
        sim_params = factory.create_simulation_parameters(
            start=datetime(2011, 7, 30, tzinfo=pytz.utc),
            end=datetime(2012, 7, 30, tzinfo=pytz.utc)
        )
        algo = TestAlgo(self, sim_params=sim_params)
        trade_source = factory.create_daily_trade_source(
            [8229],
            200,
            sim_params
        )
        algo.set_sources([trade_source])

        gen = algo.get_generator()
        self.assertTrue(list(gen))

        self.assertTrue(algo.slippage.latest_date)
        self.assertTrue(algo.latest_date)

    @timed(DEFAULT_TIMEOUT)
    def test_progress(self):
        """
        Ensure the pipeline of generators are in sync, at least as far as
        their current dates.
        """
        sim_params = factory.create_simulation_parameters(
            start=datetime(2008, 1, 1, tzinfo=pytz.utc),
            end=datetime(2008, 1, 5, tzinfo=pytz.utc)
        )
        algo = TestAlgo(self, sim_params=sim_params)
        trade_source = factory.create_daily_trade_source(
            [8229],
            3,
            sim_params
        )
        algo.set_sources([trade_source])

        gen = algo.get_generator()
        results = list(gen)
        self.assertEqual(results[-2]['progress'], 1.0)