# Copyright (c) 2023 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 semi_auto_parallel_util import SemiAutoParallelTestBase

import paddle
import paddle.distributed as dist

"""
test for concat、slice 、split
"""


class TestSplitAndConcatSemiAutoParallel(SemiAutoParallelTestBase):
    def __init__(self):
        super().__init__()

    def check_placements(self, output, expected_placements):
        assert output.placements == expected_placements, (
            f"{output.placements}  vs {expected_placements}"
        )

    def test_concat_forward(self):
        shapes = [[16, 4, 4], [64, 4, 4]]
        specs = [[None, None, 'x'], [None, None, 'x']]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.concat,
            with_backward=True,
            axis=0,
        )
        self.check_placements(outputs, [dist.Shard(2)])

    def test_concat_forward_reshard(self):
        shapes = [[16, 4, 4], [64, 4, 4]]
        specs = [['x', None, None], [None, None, 'x']]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.concat,
            with_backward=True,
            axis=0,
        )
        self.check_placements(outputs, [dist.Shard(2)])

    def test_stack_forward(self):
        shapes = [[16, 4, 4], [16, 4, 4]]
        specs = [[None, None, 'x'], [None, None, 'x']]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.stack,
            with_backward=True,
            axis=0,
        )
        self.check_placements(outputs, [dist.Shard(3)])

    def test_stack_neg_axis_forward(self):
        shapes = [[16, 4, 4], [16, 4, 4]]
        specs = [[None, None, 'x'], [None, None, 'x']]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.stack,
            with_backward=True,
            axis=-1,
        )
        self.check_placements(outputs, [dist.Shard(2)])

    def test_stack_forward_0d(self):
        shapes = []
        specs = []
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.stack,
            with_backward=True,
            axis=0,
        )
        self.check_placements(outputs, [dist.Replicate()])

    def test_stack_forward_reshard(self):
        shapes = [[16, 4, 4], [16, 4, 4]]
        specs = [['x', None, None], [None, None, 'x']]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.stack,
            with_backward=True,
            axis=0,
        )
        self.check_placements(outputs, [dist.Shard(1)])

    def test_slice(self):
        shapes = [64, 4, 4]
        specs = [None, None, 'x']
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.slice,
            with_backward=True,
            axes=[0, 1],
            starts=[1, 1],
            ends=[3, 3],
        )

    def test_decrease_axes_slice_shard(self):
        def decrease_axes_slice(x):
            return x[0]

        shapes = [64, 4, 4]
        specs = ["x", None, None]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=decrease_axes_slice,
            with_backward=True,
        )
        self.check_placements(outputs, [dist.Replicate()])

    def test_decrease_axes_slice(self):
        def decrease_axes_slice(x):
            return x[0]

        shapes = [64, 4, 4]
        specs = [None, None, 'x']
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=decrease_axes_slice,
            with_backward=True,
        )
        self.check_placements(outputs, [dist.Shard(1)])

    def test_slice_reshard(self):
        shapes = [64, 4, 4]
        specs = [None, 'x', None]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.slice,
            with_backward=True,
            axes=[0, 1],
            starts=[1, 1],
            ends=[3, 3],
        )

    def test_stride_slice(self):
        shapes = [64, 4, 4]
        specs = [None, None, 'x']
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.strided_slice,
            with_backward=True,
            axes=[0, 1],
            starts=[1, 3],
            ends=[3, 1],
            strides=[1, -1],
        )

    def test_stride_slice_reshard(self):
        shapes = [64, 4, 4]
        specs = [None, 'x', None]
        inputs, outputs = self.runfunc_and_check(
            inputs_shape=shapes,
            inputs_specs=specs,
            op_func=paddle.strided_slice,
            with_backward=True,
            axes=[0, 1],
            starts=[1, 3],
            ends=[3, 1],
            strides=[1, -1],
        )

    def run_test_case(self):
        if self._backend == "cpu":
            paddle.set_device("cpu")
        elif self._backend == "gpu":
            paddle.set_device("gpu:" + str(dist.get_rank()))
        else:
            raise ValueError("Only support cpu or gpu backend.")

        self.test_concat_forward()
        self.test_stack_forward()
        self.test_slice()
        self.test_stride_slice()
        self.test_decrease_axes_slice()
        # all to all is not supported yet for cpu
        if self._backend == "gpu":
            self.test_concat_forward_reshard()
            self.test_slice_reshard()
            self.test_stride_slice_reshard()
            self.test_stack_forward_reshard()
            self.test_stack_neg_axis_forward()
            self.test_decrease_axes_slice_shard()


if __name__ == '__main__':
    TestSplitAndConcatSemiAutoParallel().run_test_case()