import warnings

from mock import patch
import numpy as np
import pandas as pd
from pandas.io.common import PerformanceWarning

from zipline import TradingAlgorithm
from zipline.finance.trading import SimulationParameters
from zipline.protocol import BarData
from zipline.testing import (
    MockDailyBarReader,
    create_daily_df_for_asset,
    create_minute_df_for_asset,
    str_to_seconds,
)
from zipline.testing.fixtures import (
    WithDataPortal,
    WithSimParams,
    ZiplineTestCase,
)
from zipline.zipline_warnings import ZiplineDeprecationWarning

simple_algo = """
from zipline.api import sid, order
def initialize(context):
    pass

def handle_data(context, data):
    assert sid(1) in data
    assert sid(2) in data
    assert len(data) == 3
    for asset in data:
        pass
"""

history_algo = """
from zipline.api import sid, history

def initialize(context):
    context.sid1 = sid(1)

def handle_data(context, data):
    context.history_window = history(5, "1m", "volume")
"""

history_bts_algo = """
from zipline.api import sid, history, record

def initialize(context):
    context.sid3 = sid(3)
    context.num_bts = 0

def before_trading_start(context, data):
    context.num_bts += 1

    # Get history at the second BTS (beginning of second day)
    if context.num_bts == 2:
        record(history=history(5, "1m", "volume"))

def handle_data(context, data):
    pass
"""

simple_transforms_algo = """
from zipline.api import sid
def initialize(context):
    context.count = 0

def handle_data(context, data):
    if context.count == 2:
        context.mavg = data[sid(1)].mavg(5)
        context.vwap = data[sid(1)].vwap(5)
        context.stddev = data[sid(1)].stddev(5)
        context.returns = data[sid(1)].returns()

    context.count += 1
"""

manipulation_algo = """
def initialize(context):
    context.asset1 = sid(1)
    context.asset2 = sid(2)

def handle_data(context, data):
    assert len(data) == 2
    assert len(data.keys()) == 2
    assert context.asset1 in data.keys()
    assert context.asset2 in data.keys()
"""

sid_accessor_algo = """
from zipline.api import sid

def initialize(context):
    context.asset1 = sid(1)

def handle_data(context,data):
    assert data[sid(1)].sid == context.asset1
    assert data[sid(1)]["sid"] == context.asset1
"""

data_items_algo = """
from zipline.api import sid

def initialize(context):
    context.asset1 = sid(1)
    context.asset2 = sid(2)

def handle_data(context, data):
    iter_list = list(data.iteritems())
    items_list = data.items()
    assert iter_list == items_list
"""


class TestAPIShim(WithDataPortal, WithSimParams, ZiplineTestCase):
    START_DATE = pd.Timestamp("2016-01-05", tz='UTC')
    END_DATE = pd.Timestamp("2016-01-28", tz='UTC')
    SIM_PARAMS_DATA_FREQUENCY = 'minute'

    sids = ASSET_FINDER_EQUITY_SIDS = 1, 2, 3

    @classmethod
    def make_equity_minute_bar_data(cls):
        for sid in cls.sids:
            yield sid, create_minute_df_for_asset(
                cls.trading_calendar,
                cls.SIM_PARAMS_START,
                cls.SIM_PARAMS_END,
            )

    @classmethod
    def make_equity_daily_bar_data(cls):
        for sid in cls.sids:
            yield sid, create_daily_df_for_asset(
                cls.trading_calendar,
                cls.SIM_PARAMS_START,
                cls.SIM_PARAMS_END,
            )

    @classmethod
    def make_splits_data(cls):
        return pd.DataFrame([
            {
                'effective_date': str_to_seconds('2016-01-06'),
                'ratio': 0.5,
                'sid': 3,
            }
        ])

    @classmethod
    def make_adjustment_writer_equity_daily_bar_reader(cls):
        return MockDailyBarReader()

    @classmethod
    def init_class_fixtures(cls):
        super(TestAPIShim, cls).init_class_fixtures()

        cls.asset1 = cls.env.asset_finder.retrieve_asset(1)
        cls.asset2 = cls.env.asset_finder.retrieve_asset(2)
        cls.asset3 = cls.env.asset_finder.retrieve_asset(3)

    def create_algo(self, code, filename=None, sim_params=None):
        if sim_params is None:
            sim_params = self.sim_params

        return TradingAlgorithm(
            script=code,
            sim_params=sim_params,
            env=self.env,
            algo_filename=filename
        )

    def test_old_new_data_api_paths(self):
        """
        Test that the new and old data APIs hit the same code paths.

        We want to ensure that the old data API(data[sid(N)].field and
        similar)  and the new data API(data.current(sid(N), field) and
        similar) hit the same code paths on the DataPortal.
        """
        test_start_minute = self.trading_calendar.minutes_for_session(
            self.sim_params.sessions[0]
        )[1]
        test_end_minute = self.trading_calendar.minutes_for_session(
            self.sim_params.sessions[0]
        )[-1]
        bar_data = BarData(
            self.data_portal,
            lambda: test_end_minute, "minute"
        )
        ohlcvp_fields = [
            "open",
            "high",
            "low"
            "close",
            "volume",
            "price",
        ]
        spot_value_meth = 'zipline.data.data_portal.DataPortal.get_spot_value'

        def assert_get_spot_value_called(fun, field):
            """
            Assert that get_spot_value was called during the execution of fun.

            Takes in a function fun and a string field.
            """
            with patch(spot_value_meth) as gsv:
                fun()
                gsv.assert_called_with(
                    self.asset1,
                    field,
                    test_end_minute,
                    'minute'
                )
        # Ensure that data.current(sid(n), field) has the same behaviour as
        # data[sid(n)].field.
        for field in ohlcvp_fields:
            assert_get_spot_value_called(
                lambda: getattr(bar_data[self.asset1], field),
                field,
            )
            assert_get_spot_value_called(
                lambda: bar_data.current(self.asset1, field),
                field,
            )

        history_meth = 'zipline.data.data_portal.DataPortal.get_history_window'

        def assert_get_history_window_called(fun, is_legacy):
            """
            Assert that get_history_window was called during fun().

            Takes in a function fun and a boolean is_legacy.
            """
            with patch(history_meth) as ghw:
                fun()
                # Slightly hacky, but done to get around the fact that
                # history( explicitly passes an ffill param as the last arg,
                # while data.history doesn't.
                if is_legacy:
                    ghw.assert_called_with(
                        [self.asset1, self.asset2, self.asset3],
                        test_end_minute,
                        5,
                        "1m",
                        "volume",
                        True
                    )
                else:
                    ghw.assert_called_with(
                        [self.asset1, self.asset2, self.asset3],
                        test_end_minute,
                        5,
                        "1m",
                        "volume",
                    )

        test_sim_params = SimulationParameters(
            start_session=test_start_minute,
            end_session=test_end_minute,
            data_frequency="minute",
            trading_calendar=self.trading_calendar,
        )

        history_algorithm = self.create_algo(
            history_algo,
            sim_params=test_sim_params
        )
        assert_get_history_window_called(
            lambda: history_algorithm.run(self.data_portal),
            is_legacy=True
        )
        assert_get_history_window_called(
            lambda: bar_data.history(
                [self.asset1, self.asset2, self.asset3],
                "volume",
                5,
                "1m"
            ),
            is_legacy=False
        )

    def test_sid_accessor(self):
        """
        Test that we maintain backwards compat for sid access on a data object.

        We want to support both data[sid(24)].sid, as well as
        data[sid(24)]["sid"]. Since these are deprecated and will eventually
        cease to be supported, we also want to assert that we're seeing a
        deprecation warning.
        """
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)
            algo = self.create_algo(sid_accessor_algo)
            algo.run(self.data_portal)

            # Since we're already raising a warning on doing data[sid(x)],
            # we don't want to raise an extra warning on data[sid(x)].sid.
            self.assertEqual(2, len(w))

            # Check that both the warnings raised were in fact
            # ZiplineDeprecationWarnings
            for warning in w:
                self.assertEqual(
                    ZiplineDeprecationWarning,
                    warning.category
                )
                self.assertEqual(
                    "`data[sid(N)]` is deprecated. Use `data.current`.",
                    str(warning.message)
                )

    def test_data_items(self):
        """
        Test that we maintain backwards compat for data.[items | iteritems].

        We also want to assert that we warn that iterating over the assets
        in `data` is deprecated.
        """
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)
            algo = self.create_algo(data_items_algo)
            algo.run(self.data_portal)

            self.assertEqual(4, len(w))

            for idx, warning in enumerate(w):
                self.assertEqual(
                    ZiplineDeprecationWarning,
                    warning.category
                )
                if idx % 2 == 0:
                    self.assertEqual(
                        "Iterating over the assets in `data` is deprecated.",
                        str(warning.message)
                    )
                else:
                    self.assertEqual(
                        "`data[sid(N)]` is deprecated. Use `data.current`.",
                        str(warning.message)
                    )

    def test_iterate_data(self):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)

            algo = self.create_algo(simple_algo)
            algo.run(self.data_portal)

            self.assertEqual(4, len(w))

            line_nos = [warning.lineno for warning in w]
            self.assertEqual(4, len(set(line_nos)))

            for idx, warning in enumerate(w):
                self.assertEqual(ZiplineDeprecationWarning,
                                 warning.category)

                self.assertEqual("<string>", warning.filename)
                self.assertEqual(line_nos[idx], warning.lineno)

                if idx < 2:
                    self.assertEqual(
                        "Checking whether an asset is in data is deprecated.",
                        str(warning.message)
                    )
                else:
                    self.assertEqual(
                        "Iterating over the assets in `data` is deprecated.",
                        str(warning.message)
                    )

    def test_history(self):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)

            sim_params = self.sim_params.create_new(
                self.sim_params.sessions[1],
                self.sim_params.end_session
            )

            algo = self.create_algo(history_algo,
                                    sim_params=sim_params)
            algo.run(self.data_portal)

            self.assertEqual(1, len(w))
            self.assertEqual(ZiplineDeprecationWarning, w[0].category)
            self.assertEqual("<string>", w[0].filename)
            self.assertEqual(8, w[0].lineno)
            self.assertEqual("The `history` method is deprecated.  Use "
                             "`data.history` instead.", str(w[0].message))

    def test_old_new_history_bts_paths(self):
        """
        Tests that calling history in before_trading_start gets us the correct
        values, which involves 1) calling data_portal.get_history_window as of
        the previous market minute, 2) getting adjustments between the previous
        market minute and the current time, and 3) applying those adjustments
        """
        algo = self.create_algo(history_bts_algo)
        algo.run(self.data_portal)

        expected_vol_without_split = np.arange(386, 391) * 100
        expected_vol_with_split = np.arange(386, 391) * 200

        window = algo.recorded_vars['history']
        np.testing.assert_array_equal(window[self.asset1].values,
                                      expected_vol_without_split)
        np.testing.assert_array_equal(window[self.asset2].values,
                                      expected_vol_without_split)
        np.testing.assert_array_equal(window[self.asset3].values,
                                      expected_vol_with_split)

    def test_simple_transforms(self):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)

            sim_params = SimulationParameters(
                start_session=self.sim_params.sessions[8],
                end_session=self.sim_params.sessions[-1],
                data_frequency="minute",
                trading_calendar=self.trading_calendar,
            )

            algo = self.create_algo(simple_transforms_algo,
                                    sim_params=sim_params)
            algo.run(self.data_portal)

            self.assertEqual(8, len(w))
            transforms = ["mavg", "vwap", "stddev", "returns"]

            for idx, line_no in enumerate(range(8, 12)):
                warning1 = w[idx * 2]
                warning2 = w[(idx * 2) + 1]

                self.assertEqual("<string>", warning1.filename)
                self.assertEqual("<string>", warning2.filename)

                self.assertEqual(line_no, warning1.lineno)
                self.assertEqual(line_no, warning2.lineno)

                self.assertEqual("`data[sid(N)]` is deprecated. Use "
                                 "`data.current`.",
                                 str(warning1.message))
                self.assertEqual("The `{0}` method is "
                                 "deprecated.".format(transforms[idx]),
                                 str(warning2.message))

            # now verify the transform values
            # minute price
            # 2016-01-11 14:31:00+00:00    1561
            # ...
            # 2016-01-14 20:59:00+00:00    3119
            # 2016-01-14 21:00:00+00:00    3120
            # 2016-01-15 14:31:00+00:00    3121
            # 2016-01-15 14:32:00+00:00    3122
            # 2016-01-15 14:33:00+00:00    3123

            # volume
            # 2016-01-11 14:31:00+00:00    156100
            # ...
            # 2016-01-14 20:59:00+00:00    311900
            # 2016-01-14 21:00:00+00:00    312000
            # 2016-01-15 14:31:00+00:00    312100
            # 2016-01-15 14:32:00+00:00    312200
            # 2016-01-15 14:33:00+00:00    312300

            # daily price (last day built with minute data)
            # 2016-01-14 00:00:00+00:00       9
            # 2016-01-15 00:00:00+00:00    3123

            # mavg = average of all the prices = (1561 + 3123) / 2 = 2342
            # vwap = sum(price * volume) / sum(volumes)
            #      = 889119531400.0 / 366054600.0
            #      = 2428.9259891830343
            # stddev = stddev(price, ddof=1) = 451.3435498597493
            # returns = (todayprice - yesterdayprice) / yesterdayprice
            #         = (3123 - 9) / 9 = 346
            self.assertEqual(2342, algo.mavg)
            self.assertAlmostEqual(2428.92599, algo.vwap, places=5)
            self.assertAlmostEqual(451.34355, algo.stddev, places=5)
            self.assertAlmostEqual(346, algo.returns)

    def test_manipulation(self):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("ignore", PerformanceWarning)
            warnings.simplefilter("default", ZiplineDeprecationWarning)

            algo = self.create_algo(simple_algo)
            algo.run(self.data_portal)

            self.assertEqual(4, len(w))

            for idx, warning in enumerate(w):
                self.assertEqual("<string>", warning.filename)
                self.assertEqual(7 + idx, warning.lineno)

                if idx < 2:
                    self.assertEqual("Checking whether an asset is in data is "
                                     "deprecated.",
                                     str(warning.message))
                else:
                    self.assertEqual("Iterating over the assets in `data` is "
                                     "deprecated.",
                                     str(warning.message))