#   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
#
# 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 print_function

import unittest
import numpy as np
import paddle.fluid.core as core
from op_test import OpTest
import paddle.fluid as fluid
import paddle.fluid.layers as layers
import paddle


# Situation 1: starts(list, no tensor), ends(list, no tensor)
# 1.1 without attr(decrease)
class TestSliceOp(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {'Input': self.input}
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts,
            'ends': self.ends,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [3, 3, 4]
        self.axes = [0, 1, 2]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[1:3, 0:3, 2:4, :]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


class TestCase1(TestSliceOp):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [-3, 0, 2]
        self.ends = [3, 100, -1]
        self.axes = [0, 1, 2]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[-3:3, 0:100, 2:-1, :]


class TestCase2(TestSliceOp):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [-3, 0, 2]
        self.ends = [3, 100, -1]
        self.axes = [0, 1, 3]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[-3:3, 0:100, :, 2:-1]


# 1.2 with attr(decrease)
class TestSliceOp_decs_dim(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {'Input': self.input}
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts,
            'ends': self.ends,
            'infer_flags': self.infer_flags,
            'decrease_axis': self.decrease_axis,
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [2, 3, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[1, 0:3, 2:4, :]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


class TestSliceOp_decs_dim_2(TestSliceOp_decs_dim):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [2, 1, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0, 1]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[1, 0, 2:4, :]


class TestSliceOp_decs_dim_3(TestSliceOp_decs_dim):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [-1, 0, 2]
        self.ends = [1000000, 1, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0, 1]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[-1, 0, 2:4, :]


class TestSliceOp_decs_dim_4(TestSliceOp_decs_dim):
    def config(self):
        self.input = np.random.random([3, 4, 5, 7]).astype("float64")
        self.starts = [0, 1, 2, 3]
        self.ends = [1, 2, 3, 4]
        self.axes = [0, 1, 2, 3]
        self.decrease_axis = [0, 1, 2, 3]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[0, 1, 2, 3:4]


class TestSliceOp_decs_dim_5(TestSliceOp_decs_dim):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [-1]
        self.ends = [1000000]
        self.axes = [3]
        self.decrease_axis = [3]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[:, :, :, -1]


class TestSliceOp_decs_dim_6(TestSliceOp_decs_dim):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [0, 1, 2, 3]
        self.ends = [1, 2, 3, 4]
        self.axes = [0, 1, 2, 3]
        self.decrease_axis = [0, 1, 2, 3]
        self.infer_flags = [1, 1, 1]
        self.out = self.input[0, 1, 2, 3:4]


# Situation 2: starts(list, have tensor), ends(list, no tensor)
# without attr(decrease)
class TestSliceOp_starts_ListTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()

        starts_tensor = []
        for index, ele in enumerate(self.starts):
            starts_tensor.append(("x" + str(index), np.ones(
                (1)).astype('int64') * ele))

        self.inputs = {'Input': self.input, 'StartsTensorList': starts_tensor}
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts_infer,
            'ends': self.ends,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [3, 3, 4]
        self.axes = [0, 1, 2]
        self.infer_flags = [-1, 1, -1]
        self.out = self.input[1:3, 0:3, 2:4, :]

        self.starts_infer = [-1, 0, -1]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


# Situation 2: starts(list, have tensor), ends(list, no tensor)
#  with attr(decrease)
class TestSliceOp_decs_dim_starts_ListTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()

        starts_tensor = []
        for index, ele in enumerate(self.starts):
            starts_tensor.append(("x" + str(index), np.ones(
                (1)).astype('int32') * ele))

        self.inputs = {'Input': self.input, 'StartsTensorList': starts_tensor}

        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts_infer,
            'ends': self.ends,
            'infer_flags': self.infer_flags,
            'decrease_axis': self.decrease_axis,
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [2, 3, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0]
        self.infer_flags = [1, -1, 1]
        self.out = self.input[1, 0:3, 2:4, :]

        self.starts_infer = [1, -1, 2]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


class TestSliceOp_decs_dim_5_starts_ListTensor(
        TestSliceOp_decs_dim_starts_ListTensor):
    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [-1]
        self.ends = [1000000]
        self.axes = [3]
        self.decrease_axis = [3]
        self.infer_flags = [-1]
        self.out = self.input[:, :, :, -1]

        self.starts_infer = [-1]


# Situation 3: starts(tensor), ends(list, no tensor)
# with attr(decrease)
class TestSliceOp_decs_dim_starts_OneTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {
            'Input': self.input,
            "StartsTensor": np.array(
                self.starts, dtype="int32")
        }
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            #'starts': self.starts,
            'ends': self.ends,
            'infer_flags': self.infer_flags,
            'decrease_axis': self.decrease_axis,
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [2, 3, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0]
        self.infer_flags = [-1, -1, -1]
        self.out = self.input[1, 0:3, 2:4, :]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


# Situation 4: starts(tensor), ends(tensor)
#  without attr(decrease)
class TestSliceOp_starts_OneTensor_ends_OneTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()

        self.inputs = {
            'Input': self.input,
            "StartsTensor": np.array(
                self.starts, dtype="int64"),
            "EndsTensor": np.array(
                self.ends, dtype="int32")
        }
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            #'starts': self.starts,
            #'ends': self.ends_infer,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [3, 3, 4]
        self.axes = [0, 1, 2]
        self.infer_flags = [-1, -1, -1]
        self.out = self.input[1:3, 0:3, 2:4, :]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


# Situation 5: starts(tensor), ends(tensor)
#  with attr(decrease)
class TestSliceOp_decs_dim_starts_and_ends_OneTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {
            'Input': self.input,
            "StartsTensor": np.array(
                self.starts, dtype="int32"),
            "EndsTensor": np.array(
                self.ends, dtype="int32")
        }
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            #'starts': self.starts,
            #'ends': self.ends,
            'infer_flags': self.infer_flags,
            'decrease_axis': self.decrease_axis,
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [2, 1, 4]
        self.axes = [0, 1, 2]
        self.decrease_axis = [0, 1]
        self.infer_flags = [-1, -1, -1]
        self.out = self.input[1, 0, 2:4, :]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


# Situation 6: starts(tensor), ends(list, have tensor)
# without attr(decrease)
class TestSliceOp_starts_OneTensor_ends_ListTensor(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()

        ends_tensor = []
        for index, ele in enumerate(self.ends):
            ends_tensor.append(("y" + str(index), np.ones(
                (1)).astype('int32') * ele))

        self.inputs = {
            'Input': self.input,
            "StartsTensor": np.array(
                self.starts, dtype="int32"),
            'EndsTensorList': ends_tensor
        }
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            #'starts': self.starts,
            'ends': self.ends_infer,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.input = np.random.random([3, 4, 5, 6]).astype("float64")
        self.starts = [1, 0, 2]
        self.ends = [3, 3, 4]
        self.axes = [0, 1, 2]
        self.infer_flags = [-1, -1, -1]
        self.out = self.input[1:3, 0:3, 2:4, :]

        self.ends_infer = [-1, 3, 4]

    def test_check_output(self):
        self.check_output()

    def test_check_grad_normal(self):
        self.check_grad(['Input'], 'Out', max_relative_error=0.006)


# Test CUDA float16
@unittest.skipIf(not core.is_compiled_with_cuda(),
                 "core is not compiled with CUDA")
class TestFP16(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {'Input': self.input}
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts,
            'ends': self.ends,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.dtype = "float16"
        self.input = np.random.random([3, 4, 5, 6]).astype(self.dtype)
        self.starts = [-3, 0, 2]
        self.ends = [3, 100, -1]
        self.axes = [0, 1, 3]
        self.out = self.input[-3:3, 0:100, :, 2:-1]
        self.infer_flags = [1, 1, 1]

    def test_check_output(self):
        place = core.CUDAPlace(0)
        if core.is_float16_supported(place):
            self.check_output_with_place(place, atol=1e-5)

    def test_check_grad_normal(self):
        place = core.CUDAPlace(0)
        if core.is_float16_supported(place):
            self.check_grad_with_place(
                place, ['Input'], 'Out', max_relative_error=0.006)


@unittest.skipIf(not core.is_compiled_with_cuda(),
                 "core is not compiled with CUDA")
class TestFP16_2(OpTest):
    def setUp(self):
        self.op_type = "slice"
        self.config()
        self.inputs = {'Input': self.input}
        self.outputs = {'Out': self.out}
        self.attrs = {
            'axes': self.axes,
            'starts': self.starts,
            'ends': self.ends,
            'infer_flags': self.infer_flags
        }

    def config(self):
        self.dtype = "float16"
        self.input = np.random.random([3, 4, 10]).astype(self.dtype)
        self.starts = [0]
        self.ends = [1]
        self.axes = [1]
        self.out = self.input[:, 0:1, :]
        self.infer_flags = [1]

    def test_check_output(self):
        place = core.CUDAPlace(0)
        if core.is_float16_supported(place):
            self.check_output_with_place(place, atol=1e-5)

    def test_check_grad_normal(self):
        place = core.CUDAPlace(0)
        if core.is_float16_supported(place):
            self.check_grad_with_place(
                place, ['Input'],
                'Out',
                max_relative_error=0.006,
                numeric_grad_delta=0.5)


# Test python API
class TestSliceAPI(unittest.TestCase):
    def test_1(self):
        input = np.random.random([3, 4, 5, 6]).astype("float64")
        minus_1 = fluid.layers.fill_constant([1], "int32", -1)
        minus_3 = fluid.layers.fill_constant([1], "int64", -3)
        starts = fluid.layers.data(
            name='starts', shape=[1, 3], append_batch_size=False)
        ends = fluid.layers.data(
            name='ends', shape=[3], append_batch_size=False)

        x = fluid.layers.data(
            name="x",
            shape=[3, 4, 5, 6],
            append_batch_size=False,
            dtype="float64")

        # value_int64 is greater than 2147483647 which is the max of int32
        value_int64 = fluid.layers.fill_constant([1], "int64", 2147483648)

        out_1 = fluid.layers.slice(
            x, axes=[0, 1, 2], starts=[-3, 0, 2], ends=[value_int64, 100, -1])
        out_2 = fluid.layers.slice(
            x, axes=[0, 1, 3], starts=[minus_3, 0, 2], ends=[3, 100, -1])
        out_3 = fluid.layers.slice(
            x, axes=[0, 1, 3], starts=[minus_3, 0, 2], ends=[3, 100, minus_1])
        out_4 = fluid.layers.slice(x, axes=[0, 1, 2], starts=starts, ends=ends)

        out_5 = x[-3:3, 0:100, 2:-1]
        out_6 = x[minus_3:3, 0:100, :, 2:-1]
        out_7 = x[minus_1, 0:100, :, 2:minus_1]

        exe = fluid.Executor(place=fluid.CPUPlace())
        res_1, res_2, res_3, res_4, res_5, res_6, res_7 = exe.run(
            fluid.default_main_program(),
            feed={
                "x": input,
                'starts': np.array([-3, 0, 2]).astype("int32"),
                'ends': np.array([3, 100, -1]).astype("int32")
            },
            fetch_list=[out_1, out_2, out_3, out_4, out_5, out_6, out_7])

        assert np.array_equal(res_1, input[-3:3, 0:100, 2:-1, :])
        assert np.array_equal(res_2, input[-3:3, 0:100, :, 2:-1])
        assert np.array_equal(res_3, input[-3:3, 0:100, :, 2:-1])
        assert np.array_equal(res_4, input[-3:3, 0:100, 2:-1, :])
        assert np.array_equal(res_5, input[-3:3, 0:100, 2:-1, :])
        assert np.array_equal(res_6, input[-3:3, 0:100, :, 2:-1])
        assert np.array_equal(res_7, input[-1, 0:100, :, 2:-1])


class TestSliceApiWithTensor(unittest.TestCase):
    def test_starts_ends_is_tensor(self):
        with paddle.fluid.dygraph.guard():
            a = paddle.rand(shape=[4, 5, 6], dtype='float32')
            axes = [0, 1, 2]
            starts = [-3, 0, 2]
            ends = [3, 2, 4]
            a_1 = paddle.slice(
                a,
                axes=axes,
                starts=paddle.to_tensor(
                    starts, dtype='int32'),
                ends=paddle.to_tensor(
                    ends, dtype='int32'))
            a_2 = paddle.slice(a, axes=axes, starts=starts, ends=ends)

            self.assertTrue(np.array_equal(a_1.numpy(), a_2.numpy()))


class TestSliceApiWithLoDTensorArray(unittest.TestCase):
    def setUp(self):
        self.shape = (3, 4)
        self.data = np.random.random(size=self.shape).astype('float32')
        self.idx = 0
        self.start = 0
        self.end = 2
        self.axis = 1

        self.place = fluid.CUDAPlace(0) if fluid.is_compiled_with_cuda(
        ) else fluid.CPUPlace()
        self.exe = fluid.Executor(self.place)

    def set_program_and_run(self, main_program, case_num):
        with fluid.program_guard(main_program):
            x = [
                fluid.data(
                    name='x0', shape=self.shape, dtype="float32"), fluid.data(
                        name='x1', shape=self.shape, dtype="float32"),
                fluid.data(
                    name='x2', shape=self.shape, dtype="float32")
            ]

            for each_x in x:
                each_x.stop_gradient = False

            arr = layers.create_array(dtype="float32")
            for i in range(3):
                idx = layers.array_length(arr)
                arr = layers.array_write(x=x[i], i=idx, array=arr)

            if case_num == 1:
                self.sliced_arr = output = arr[0]

            elif case_num == 2:
                end = fluid.layers.array_length(
                    arr) - 1  # dtype of end is int64
                self.sliced_arr = slice_arr = arr[self.start:end]
                output, _ = fluid.layers.tensor_array_to_tensor(
                    slice_arr, axis=self.axis, use_stack=True)
            elif case_num == 3:
                value_int64 = fluid.layers.fill_constant([1], "int64",
                                                         2147483648)
                self.sliced_arr = slice_arr = arr[self.start:value_int64]
                output, _ = fluid.layers.tensor_array_to_tensor(
                    slice_arr, axis=self.axis, use_stack=True)

            loss = fluid.layers.reduce_sum(output)
            fluid.backward.append_backward(loss)
            g_vars = list(
                map(main_program.global_block().var,
                    [each_x.name + "@GRAD" for each_x in x]))
            self.out, self.g_x0, self.g_x1, self.g_x2 = \
                self.exe.run(main_program,
                             feed = {'x0': self.data,
                                     'x1': self.data,
                                     'x2': self.data},
                             fetch_list=[output] + g_vars)

    def test_case_1(self):
        main_program = fluid.Program()
        self.set_program_and_run(main_program, 1)

        self.assertTrue(self.sliced_arr.type == core.VarDesc.VarType.LOD_TENSOR)
        self.assertEqual(self.sliced_arr.shape, self.shape)
        self.assertTrue(np.array_equal(self.out, self.data))
        self.assertTrue(np.array_equal(self.g_x0, np.ones_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x1, np.zeros_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x2, np.zeros_like(self.data)))

    def test_case_2(self):
        main_program = fluid.Program()
        self.set_program_and_run(main_program, 2)

        self.assertTrue(
            self.sliced_arr.type == core.VarDesc.VarType.LOD_TENSOR_ARRAY)
        self.assertEqual(self.sliced_arr.shape, self.shape)
        self.assertTrue(
            np.array_equal(
                self.out, np.stack(
                    [self.data, self.data], axis=self.axis)))
        self.assertTrue(np.array_equal(self.g_x0, np.ones_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x1, np.ones_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x2, np.zeros_like(self.data)))

    def test_case_3(self):
        main_program = fluid.Program()
        self.set_program_and_run(main_program, 3)

        self.assertTrue(
            self.sliced_arr.type == core.VarDesc.VarType.LOD_TENSOR_ARRAY)
        self.assertEqual(self.sliced_arr.shape, self.shape)
        self.assertTrue(
            np.array_equal(
                self.out,
                np.stack(
                    [self.data, self.data, self.data], axis=self.axis)))
        self.assertTrue(np.array_equal(self.g_x0, np.ones_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x1, np.ones_like(self.data)))
        self.assertTrue(np.array_equal(self.g_x2, np.ones_like(self.data)))


class TestImperativeVarBaseGetItem(unittest.TestCase):
    def test_getitem_with_long(self):
        with fluid.dygraph.guard():
            data = np.random.random((2, 80, 16128)).astype('float32')
            var = fluid.dygraph.to_variable(data)
            sliced = var[:, 10:, :var.shape[1]]  # var.shape[1] is 80L here
            self.assertEqual(sliced.shape, [2, 70, 80])

            sliced = var[:, var.shape[0]:, var.shape[0]:var.shape[1]]
            self.assertEqual(sliced.shape, [2, 78, 78])

    def test_getitem_with_float(self):
        def test_float_in_slice_item():
            with fluid.dygraph.guard():
                data = np.random.random((2, 80, 16128)).astype('float32')
                var = fluid.dygraph.to_variable(data)
                sliced = var[:, 1.1:, :var.shape[1]]

        self.assertRaises(Exception, test_float_in_slice_item)

        def test_float_in_index():
            with fluid.dygraph.guard():
                data = np.random.random((2, 80, 16128)).astype('float32')
                var = fluid.dygraph.to_variable(data)
                sliced = var[1.1]

        self.assertRaises(Exception, test_float_in_index)


@unittest.skipIf(not core.is_compiled_with_cuda(),
                 "core is not compiled with CUDA")
class TestImperativeCUDAPinnedInput(unittest.TestCase):
    def test_input_cuda_pinned_var(self):
        with fluid.dygraph.guard():
            data = np.random.random((2, 80, 16128)).astype('float32')
            var = core.VarBase(
                value=data,
                name='',
                persistable=False,
                place=fluid.CUDAPinnedPlace(),
                zero_copy=False)
            sliced = var[:, 10:, :var.shape[1]]
            self.assertEqual(sliced.shape, [2, 70, 80])


if __name__ == '__main__':
    unittest.main()