import random
from unittest import TestCase
from unittest.mock import Mock

import numpy as np

from Orange.preprocess import discretize, Discretize
from Orange import data
from Orange.data import Table, Instance, Domain, ContinuousVariable, DiscreteVariable


# noinspection PyPep8Naming
class TestEqualFreq(TestCase):
    def test_equifreq_with_too_few_values(self):
        s = [0] * 50 + [1] * 50
        random.shuffle(s)
        X = np.array(s).reshape((100, 1))
        table = data.Table(X)
        disc = discretize.EqualFreq(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 2)
        self.assertEqual(dvar.compute_value.points, [0.5])

    def test_equifreq_100_to_4(self):
        X = np.arange(100).reshape((100, 1))
        table = data.Table(X)
        disc = discretize.EqualFreq(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 4)
        self.assertEqual(dvar.compute_value.points, [24.5, 49.5, 74.5])

    def test_equifreq_with_k_instances(self):
        X = np.array([[1], [2], [3], [4]])
        table = data.Table(X)
        disc = discretize.EqualFreq(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 4)
        self.assertEqual(dvar.compute_value.points, [1.5, 2.5, 3.5])


# noinspection PyPep8Naming
class TestEqualWidth(TestCase):
    def test_equalwidth_on_two_values(self):
        s = [0] * 50 + [1] * 50
        random.shuffle(s)
        X = np.array(s).reshape((100, 1))
        table = data.Table(X)
        disc = discretize.EqualWidth(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 4)
        self.assertEqual(dvar.compute_value.points, [0.25, 0.5, 0.75])

    def test_equalwidth_100_to_4(self):
        X = np.arange(101).reshape((101, 1))
        table = data.Table(X)
        disc = discretize.EqualWidth(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 4)
        self.assertEqual(dvar.compute_value.points, [25, 50, 75])

    def test_equalwidth_const_value(self):
        X = np.ones((100, 1))
        table = data.Table(X)
        disc = discretize.EqualFreq(n=4)
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 1)
        self.assertEqual(dvar.compute_value.points, [])


# noinspection PyPep8Naming
class TestEntropyMDL(TestCase):
    def test_entropy_with_two_values(self):
        s = [0] * 50 + [1] * 50
        random.shuffle(s)
        X = np.array(s).reshape((100, 1))
        table = data.Table(X, X)
        disc = discretize.EntropyMDL()
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 2)
        self.assertEqual(dvar.compute_value.points, [0.5])

    def test_entropy_with_two_values_useless(self):
        X = np.array([0] * 50 + [1] * 50).reshape((100, 1))
        Y = np.array([0] * 25 + [1] * 50 + [0] * 25)
        table = data.Table(X, Y)
        disc = discretize.EntropyMDL()
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 1)
        self.assertEqual(dvar.compute_value.points, [])

    def test_entropy_constant(self):
        X = np.zeros((100, 1))
        domain = Domain([ContinuousVariable('v1')],
                        [DiscreteVariable('c1', values=[1])])
        table = data.Table(domain, X, X)
        disc = discretize.EntropyMDL()
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 1)
        self.assertEqual(dvar.compute_value.points, [])

    def test_entropy(self):
        X = np.array([0] * 25 + [1] * 25 + [2] * 25 + [3] * 25
                     ).reshape((100, 1))
        Y = np.array([0] * 25 + [1] * 75)
        table = data.Table(X, Y)
        disc = discretize.EntropyMDL()
        dvar = disc(table, table.domain.variables[0])
        self.assertEqual(len(dvar.values), 2)
        self.assertEqual(dvar.compute_value.points, [0.5])


# noinspection PyPep8Naming
class TestDiscretizer(TestCase):
    def setUp(self):
        self.var = Mock(data.ContinuousVariable, number_of_decimals=1)
        self.var.name = "x"

    def test_create_discretized_var(self):
        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [1, 2, 3])
        self.assertIsInstance(dvar.compute_value,
                              discretize.Discretizer)
        self.assertEqual(dvar.compute_value.points, [1, 2, 3])


    def test_create_discretized_var_formatting(self):
        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [1, 2, 3])
        self.assertEqual(dvar.values, ["< 1", "1 - 2", "2 - 3", "≥ 3"])

        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [10])
        self.assertEqual(dvar.values, ["< 10", "≥ 10"])

        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [10.1234])
        self.assertEqual(dvar.values, ["< 10.1", "≥ 10.1"])

        self.var.number_of_decimals=3

        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [5, 10.1234])
        self.assertEqual(dvar.values, ["< 5", "5 - 10.123", "≥ 10.123"])

    def test_discretizer_computation(self):
        dvar = discretize.Discretizer.create_discretized_var(
            self.var, [1, 2, 3])
        X = np.array([0, 0.9, 1, 1.1, 1.9, 2, 2.5, 3, 3.5])
        np.testing.assert_equal(dvar.compute_value.transform(X), np.floor(X))

    def test_transform(self):
        table = data.Table('iris')
        table2 = Discretize(table)
        ins = data.Instance(table2.domain, table[0])
        table3 = data.Table(table2.domain, table[:10])
        self.assertEqual(ins, table3[0])

    def test_remove_constant(self):
        table = data.Table('iris')
        table[:, 0] = 1
        discretize = Discretize(remove_const=True)
        new_table = discretize(table)
        self.assertNotEqual(len(table.domain.attributes),
                            len(new_table.domain.attributes))

    def test_keep_constant(self):
        table = data.Table('iris')
        table[:, 0] = 1
        discretize = Discretize(remove_const=False)
        new_table = discretize(table)
        self.assertEqual(len(table.domain.attributes),
                         len(new_table.domain.attributes))


# noinspection PyPep8Naming
class TestDiscretizeTable(TestCase):
    def setUp(self):
        s = [0] * 50 + [1] * 50
        X1 = np.array(s).reshape((100, 1))
        X2 = np.arange(100).reshape((100, 1))
        X3 = np.ones((100, 1))
        X = np.hstack([X1, X2, X3])
        self.table_no_class = data.Table(X)
        self.table_class = data.Table(X, X1)

    def test_discretize_exclude_constant(self):
        dom = discretize.DomainDiscretizer(self.table_no_class)
        self.assertEqual(len(dom.attributes), 2)
        self.assertEqual(dom[0].compute_value.points, [0.5])
        self.assertEqual(dom[1].compute_value.points, [24.5, 49.5, 74.5])

        dom = discretize.DomainDiscretizer(self.table_no_class, clean=False)
        self.assertEqual(len(dom.attributes), 3)
        self.assertEqual(dom[0].compute_value.points, [0.5])
        self.assertEqual(dom[1].compute_value.points, [24.5, 49.5, 74.5])
        self.assertEqual(dom[2].compute_value.points, [])

        dom = discretize.DomainDiscretizer(self.table_class)
        self.assertEqual(len(dom.attributes), 2)
        self.assertEqual(dom[0].compute_value.points, [0.5])
        self.assertEqual(dom[1].compute_value.points, [24.5, 49.5, 74.5])

    def test_discretize_class(self):
        dom = discretize.DomainDiscretizer(self.table_class)
        self.assertIs(dom.class_var, self.table_class.domain.class_var)

        dom = discretize.DomainDiscretizer(self.table_class,
                                           discretize_class=True)
        self.assertIs(dom.class_var, self.table_class.domain.class_var)

    def test_method(self):
        dom = discretize.DomainDiscretizer(self.table_class)
        self.assertEqual(len(dom[1].values), 4)

        dom = discretize.DomainDiscretizer(self.table_class,
                                           method=discretize.EqualWidth(n=2))
        self.assertEqual(len(dom[1].values), 2)

    def test_fixed(self):
        dom = discretize.DomainDiscretizer(self.table_no_class,
                                           method=discretize.EqualWidth(n=2),
                                           fixed={"Feature 2": [1, 11]})
        self.assertEqual(len(dom.attributes), 2)
        self.assertEqual(dom[0].compute_value.points, [0.5])
        self.assertEqual(dom[1].compute_value.points, [6])

    def test_leave_discrete(self):
        s = [0] * 50 + [1] * 50
        X1 = np.array(s).reshape((100, 1))
        X2 = np.arange(100).reshape((100, 1))
        X3 = np.ones((100, 1))
        X = np.hstack([X1, X2, X3])
        domain = data.Domain([data.DiscreteVariable("a", values="MF"),
                              data.ContinuousVariable("b"),
                              data.DiscreteVariable("c", values="AB")],
                             data.ContinuousVariable("d"))
        table = data.Table(domain, X, X1)
        dom = discretize.DomainDiscretizer(table)
        self.assertIs(dom[0], table.domain[0])
        self.assertEqual(dom[1].compute_value.points, [24.5, 49.5, 74.5])
        self.assertIs(dom[2], table.domain[2])
        self.assertIs(dom.class_var, table.domain.class_var)

        domain = data.Domain([data.DiscreteVariable("a", values="MF"),
                              data.ContinuousVariable("b"),
                              data.DiscreteVariable("c", values="AB")],
                             data.DiscreteVariable("d"))
        table = data.Table(domain, X, X1)
        dom = discretize.DomainDiscretizer(table)
        self.assertIs(dom[0], table.domain[0])
        self.assertEqual(dom[1].compute_value.points, [24.5, 49.5, 74.5])
        self.assertIs(dom[2], table.domain[2])
        self.assertIs(dom.class_var, table.domain.class_var)


class TestInstanceConversion(TestCase):
    def test_single_instance(self):
        iris = Table("iris")
        inst = Instance(iris.domain, [5.2, 3.8, 1.4, 0.5, "Iris-virginica"])
        d_iris = Discretize(iris)
        Instance(d_iris.domain, inst)
