# coding: utf-8

""" Test cases for .hist method """

import pytest

from pandas import Series, DataFrame
import pandas.util.testing as tm
import pandas.util._test_decorators as td

import numpy as np
from numpy.random import randn

from pandas.plotting._core import grouped_hist
from pandas.plotting._compat import _mpl_ge_2_2_0
from pandas.tests.plotting.common import (TestPlotBase, _check_plot_works)


@td.skip_if_no_mpl
class TestSeriesPlots(TestPlotBase):

    def setup_method(self, method):
        TestPlotBase.setup_method(self, method)
        import matplotlib as mpl
        mpl.rcdefaults()

        self.ts = tm.makeTimeSeries()
        self.ts.name = 'ts'

    @pytest.mark.slow
    def test_hist_legacy(self):
        _check_plot_works(self.ts.hist)
        _check_plot_works(self.ts.hist, grid=False)
        _check_plot_works(self.ts.hist, figsize=(8, 10))
        # _check_plot_works adds an ax so catch warning. see GH #13188
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(self.ts.hist, by=self.ts.index.month)
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(self.ts.hist, by=self.ts.index.month, bins=5)

        fig, ax = self.plt.subplots(1, 1)
        _check_plot_works(self.ts.hist, ax=ax)
        _check_plot_works(self.ts.hist, ax=ax, figure=fig)
        _check_plot_works(self.ts.hist, figure=fig)
        tm.close()

        fig, (ax1, ax2) = self.plt.subplots(1, 2)
        _check_plot_works(self.ts.hist, figure=fig, ax=ax1)
        _check_plot_works(self.ts.hist, figure=fig, ax=ax2)

        with pytest.raises(ValueError):
            self.ts.hist(by=self.ts.index, figure=fig)

    @pytest.mark.slow
    def test_hist_bins_legacy(self):
        df = DataFrame(np.random.randn(10, 2))
        ax = df.hist(bins=2)[0][0]
        assert len(ax.patches) == 2

    @pytest.mark.slow
    def test_hist_layout(self):
        df = self.hist_df
        with pytest.raises(ValueError):
            df.height.hist(layout=(1, 1))

        with pytest.raises(ValueError):
            df.height.hist(layout=[1, 1])

    @pytest.mark.slow
    def test_hist_layout_with_by(self):
        df = self.hist_df

        # _check_plot_works adds an `ax` kwarg to the method call
        # so we get a warning about an axis being cleared, even
        # though we don't explicing pass one, see GH #13188
        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.height.hist, by=df.gender,
                                     layout=(2, 1))
        self._check_axes_shape(axes, axes_num=2, layout=(2, 1))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.height.hist, by=df.gender,
                                     layout=(3, -1))
        self._check_axes_shape(axes, axes_num=2, layout=(3, 1))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.height.hist, by=df.category,
                                     layout=(4, 1))
        self._check_axes_shape(axes, axes_num=4, layout=(4, 1))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(
                df.height.hist, by=df.category, layout=(2, -1))
        self._check_axes_shape(axes, axes_num=4, layout=(2, 2))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(
                df.height.hist, by=df.category, layout=(3, -1))
        self._check_axes_shape(axes, axes_num=4, layout=(3, 2))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(
                df.height.hist, by=df.category, layout=(-1, 4))
        self._check_axes_shape(axes, axes_num=4, layout=(1, 4))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(
                df.height.hist, by=df.classroom, layout=(2, 2))
        self._check_axes_shape(axes, axes_num=3, layout=(2, 2))

        axes = df.height.hist(by=df.category, layout=(4, 2), figsize=(12, 7))
        self._check_axes_shape(
            axes, axes_num=4, layout=(4, 2), figsize=(12, 7))

    @pytest.mark.slow
    def test_hist_no_overlap(self):
        from matplotlib.pyplot import subplot, gcf
        x = Series(randn(2))
        y = Series(randn(2))
        subplot(121)
        x.hist()
        subplot(122)
        y.hist()
        fig = gcf()
        axes = fig.axes
        assert len(axes) == 2

    @pytest.mark.slow
    def test_hist_by_no_extra_plots(self):
        df = self.hist_df
        axes = df.height.hist(by=df.gender)  # noqa
        assert len(self.plt.get_fignums()) == 1

    @pytest.mark.slow
    def test_plot_fails_when_ax_differs_from_figure(self):
        from pylab import figure
        fig1 = figure()
        fig2 = figure()
        ax1 = fig1.add_subplot(111)
        with pytest.raises(AssertionError):
            self.ts.hist(ax=ax1, figure=fig2)


@td.skip_if_no_mpl
class TestDataFramePlots(TestPlotBase):

    @pytest.mark.slow
    def test_hist_df_legacy(self):
        from matplotlib.patches import Rectangle
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(self.hist_df.hist)

        # make sure layout is handled
        df = DataFrame(randn(100, 3))
        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.hist, grid=False)
        self._check_axes_shape(axes, axes_num=3, layout=(2, 2))
        assert not axes[1, 1].get_visible()

        df = DataFrame(randn(100, 1))
        _check_plot_works(df.hist)

        # make sure layout is handled
        df = DataFrame(randn(100, 6))
        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.hist, layout=(4, 2))
        self._check_axes_shape(axes, axes_num=6, layout=(4, 2))

        # make sure sharex, sharey is handled
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(df.hist, sharex=True, sharey=True)

        # handle figsize arg
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(df.hist, figsize=(8, 10))

        # check bins argument
        with tm.assert_produces_warning(UserWarning):
            _check_plot_works(df.hist, bins=5)

        # make sure xlabelsize and xrot are handled
        ser = df[0]
        xf, yf = 20, 18
        xrot, yrot = 30, 40
        axes = ser.hist(xlabelsize=xf, xrot=xrot, ylabelsize=yf, yrot=yrot)
        self._check_ticks_props(axes, xlabelsize=xf, xrot=xrot,
                                ylabelsize=yf, yrot=yrot)

        xf, yf = 20, 18
        xrot, yrot = 30, 40
        axes = df.hist(xlabelsize=xf, xrot=xrot, ylabelsize=yf, yrot=yrot)
        self._check_ticks_props(axes, xlabelsize=xf, xrot=xrot,
                                ylabelsize=yf, yrot=yrot)

        tm.close()
        # make sure kwargs to hist are handled
        if _mpl_ge_2_2_0():
            kwargs = {"density": True}
        else:
            kwargs = {"normed": True}
        ax = ser.hist(cumulative=True, bins=4, **kwargs)
        # height of last bin (index 5) must be 1.0
        rects = [x for x in ax.get_children() if isinstance(x, Rectangle)]
        tm.assert_almost_equal(rects[-1].get_height(), 1.0)

        tm.close()
        ax = ser.hist(log=True)
        # scale of y must be 'log'
        self._check_ax_scales(ax, yaxis='log')

        tm.close()

        # propagate attr exception from matplotlib.Axes.hist
        with pytest.raises(AttributeError):
            ser.hist(foo='bar')

    @pytest.mark.slow
    def test_hist_layout(self):
        df = DataFrame(randn(100, 3))

        layout_to_expected_size = (
            {'layout': None, 'expected_size': (2, 2)},  # default is 2x2
            {'layout': (2, 2), 'expected_size': (2, 2)},
            {'layout': (4, 1), 'expected_size': (4, 1)},
            {'layout': (1, 4), 'expected_size': (1, 4)},
            {'layout': (3, 3), 'expected_size': (3, 3)},
            {'layout': (-1, 4), 'expected_size': (1, 4)},
            {'layout': (4, -1), 'expected_size': (4, 1)},
            {'layout': (-1, 2), 'expected_size': (2, 2)},
            {'layout': (2, -1), 'expected_size': (2, 2)}
        )

        for layout_test in layout_to_expected_size:
            axes = df.hist(layout=layout_test['layout'])
            expected = layout_test['expected_size']
            self._check_axes_shape(axes, axes_num=3, layout=expected)

        # layout too small for all 4 plots
        with pytest.raises(ValueError):
            df.hist(layout=(1, 1))

        # invalid format for layout
        with pytest.raises(ValueError):
            df.hist(layout=(1,))
        with pytest.raises(ValueError):
            df.hist(layout=(-1, -1))

    @pytest.mark.slow
    # GH 9351
    def test_tight_layout(self):
        if self.mpl_ge_2_0_1:
            df = DataFrame(randn(100, 3))
            _check_plot_works(df.hist)
            self.plt.tight_layout()

            tm.close()


@td.skip_if_no_mpl
class TestDataFrameGroupByPlots(TestPlotBase):

    @pytest.mark.slow
    def test_grouped_hist_legacy(self):
        from matplotlib.patches import Rectangle

        df = DataFrame(randn(500, 2), columns=['A', 'B'])
        df['C'] = np.random.randint(0, 4, 500)
        df['D'] = ['X'] * 500

        axes = grouped_hist(df.A, by=df.C)
        self._check_axes_shape(axes, axes_num=4, layout=(2, 2))

        tm.close()
        axes = df.hist(by=df.C)
        self._check_axes_shape(axes, axes_num=4, layout=(2, 2))

        tm.close()
        # group by a key with single value
        axes = df.hist(by='D', rot=30)
        self._check_axes_shape(axes, axes_num=1, layout=(1, 1))
        self._check_ticks_props(axes, xrot=30)

        tm.close()
        # make sure kwargs to hist are handled
        xf, yf = 20, 18
        xrot, yrot = 30, 40

        if _mpl_ge_2_2_0():
            kwargs = {"density": True}
        else:
            kwargs = {"normed": True}

        axes = grouped_hist(df.A, by=df.C, cumulative=True,
                            bins=4, xlabelsize=xf, xrot=xrot,
                            ylabelsize=yf, yrot=yrot, **kwargs)
        # height of last bin (index 5) must be 1.0
        for ax in axes.ravel():
            rects = [x for x in ax.get_children() if isinstance(x, Rectangle)]
            height = rects[-1].get_height()
            tm.assert_almost_equal(height, 1.0)
        self._check_ticks_props(axes, xlabelsize=xf, xrot=xrot,
                                ylabelsize=yf, yrot=yrot)

        tm.close()
        axes = grouped_hist(df.A, by=df.C, log=True)
        # scale of y must be 'log'
        self._check_ax_scales(axes, yaxis='log')

        tm.close()
        # propagate attr exception from matplotlib.Axes.hist
        with pytest.raises(AttributeError):
            grouped_hist(df.A, by=df.C, foo='bar')

        with tm.assert_produces_warning(FutureWarning):
            df.hist(by='C', figsize='default')

    @pytest.mark.slow
    def test_grouped_hist_legacy2(self):
        n = 10
        weight = Series(np.random.normal(166, 20, size=n))
        height = Series(np.random.normal(60, 10, size=n))
        with tm.RNGContext(42):
            gender_int = np.random.choice([0, 1], size=n)
        df_int = DataFrame({'height': height, 'weight': weight,
                            'gender': gender_int})
        gb = df_int.groupby('gender')
        axes = gb.hist()
        assert len(axes) == 2
        assert len(self.plt.get_fignums()) == 2
        tm.close()

    @pytest.mark.slow
    def test_grouped_hist_layout(self):
        df = self.hist_df
        pytest.raises(ValueError, df.hist, column='weight', by=df.gender,
                      layout=(1, 1))
        pytest.raises(ValueError, df.hist, column='height', by=df.category,
                      layout=(1, 3))
        pytest.raises(ValueError, df.hist, column='height', by=df.category,
                      layout=(-1, -1))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.hist, column='height', by=df.gender,
                                     layout=(2, 1))
        self._check_axes_shape(axes, axes_num=2, layout=(2, 1))

        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.hist, column='height', by=df.gender,
                                     layout=(2, -1))
        self._check_axes_shape(axes, axes_num=2, layout=(2, 1))

        axes = df.hist(column='height', by=df.category, layout=(4, 1))
        self._check_axes_shape(axes, axes_num=4, layout=(4, 1))

        axes = df.hist(column='height', by=df.category, layout=(-1, 1))
        self._check_axes_shape(axes, axes_num=4, layout=(4, 1))

        axes = df.hist(column='height', by=df.category,
                       layout=(4, 2), figsize=(12, 8))
        self._check_axes_shape(
            axes, axes_num=4, layout=(4, 2), figsize=(12, 8))
        tm.close()

        # GH 6769
        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(
                df.hist, column='height', by='classroom', layout=(2, 2))
        self._check_axes_shape(axes, axes_num=3, layout=(2, 2))

        # without column
        with tm.assert_produces_warning(UserWarning):
            axes = _check_plot_works(df.hist, by='classroom')
        self._check_axes_shape(axes, axes_num=3, layout=(2, 2))

        axes = df.hist(by='gender', layout=(3, 5))
        self._check_axes_shape(axes, axes_num=2, layout=(3, 5))

        axes = df.hist(column=['height', 'weight', 'category'])
        self._check_axes_shape(axes, axes_num=3, layout=(2, 2))

    @pytest.mark.slow
    def test_grouped_hist_multiple_axes(self):
        # GH 6970, GH 7069
        df = self.hist_df

        fig, axes = self.plt.subplots(2, 3)
        returned = df.hist(column=['height', 'weight', 'category'], ax=axes[0])
        self._check_axes_shape(returned, axes_num=3, layout=(1, 3))
        tm.assert_numpy_array_equal(returned, axes[0])
        assert returned[0].figure is fig
        returned = df.hist(by='classroom', ax=axes[1])
        self._check_axes_shape(returned, axes_num=3, layout=(1, 3))
        tm.assert_numpy_array_equal(returned, axes[1])
        assert returned[0].figure is fig

        with pytest.raises(ValueError):
            fig, axes = self.plt.subplots(2, 3)
            # pass different number of axes from required
            axes = df.hist(column='height', ax=axes)

    @pytest.mark.slow
    def test_axis_share_x(self):
        df = self.hist_df
        # GH4089
        ax1, ax2 = df.hist(column='height', by=df.gender, sharex=True)

        # share x
        assert ax1._shared_x_axes.joined(ax1, ax2)
        assert ax2._shared_x_axes.joined(ax1, ax2)

        # don't share y
        assert not ax1._shared_y_axes.joined(ax1, ax2)
        assert not ax2._shared_y_axes.joined(ax1, ax2)

    @pytest.mark.slow
    def test_axis_share_y(self):
        df = self.hist_df
        ax1, ax2 = df.hist(column='height', by=df.gender, sharey=True)

        # share y
        assert ax1._shared_y_axes.joined(ax1, ax2)
        assert ax2._shared_y_axes.joined(ax1, ax2)

        # don't share x
        assert not ax1._shared_x_axes.joined(ax1, ax2)
        assert not ax2._shared_x_axes.joined(ax1, ax2)

    @pytest.mark.slow
    def test_axis_share_xy(self):
        df = self.hist_df
        ax1, ax2 = df.hist(column='height', by=df.gender, sharex=True,
                           sharey=True)

        # share both x and y
        assert ax1._shared_x_axes.joined(ax1, ax2)
        assert ax2._shared_x_axes.joined(ax1, ax2)

        assert ax1._shared_y_axes.joined(ax1, ax2)
        assert ax2._shared_y_axes.joined(ax1, ax2)
