# 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.

import unittest

# import torch
import numpy as np
from op_test import get_places

import paddle

np.random.seed(10)


def numpy_polar(abs, angle):
    real = np.multiply(abs, np.cos(angle))
    imag = np.multiply(abs, np.sin(angle))
    return real + imag * 1j


class TestPolarAPI(unittest.TestCase):
    def setUp(self):
        self.abs = np.array([1, 2]).astype("float64")
        self.angle = np.array([np.pi / 2, 5 * np.pi / 4]).astype("float64")
        self.place = get_places()

    def test_api_static(self):
        paddle.enable_static()

        def run(place):
            with paddle.static.program_guard(paddle.static.Program()):
                abs = paddle.static.data(
                    'abs',
                    shape=self.abs.shape,
                    dtype="float64",
                )
                angle = paddle.static.data(
                    'angle', shape=self.angle.shape, dtype="float64"
                )
                out1 = paddle.polar(abs, angle)
                exe = paddle.static.Executor(place)
                res = exe.run(
                    feed={'abs': self.abs, 'angle': self.angle},
                    fetch_list=[out1],
                )
            out_ref = numpy_polar(self.abs, self.angle)
            np.testing.assert_allclose(out_ref, res[0], rtol=1e-05)

        for place in self.place:
            run(place)

    def test_api_dygraph(self):
        def run(place):
            paddle.disable_static(place)
            abs = paddle.to_tensor(self.abs)
            angle = paddle.to_tensor(self.angle)
            out1 = paddle.polar(abs, angle)

            out_ref1 = numpy_polar(self.abs, self.angle)
            np.testing.assert_allclose(out_ref1, out1.numpy(), rtol=1e-05)
            paddle.enable_static()

        for place in self.place:
            run(place)

    def test_out_complex64(self):
        paddle.disable_static()
        abs = paddle.to_tensor(self.abs, dtype=paddle.float32)
        angle = paddle.to_tensor(self.angle, dtype=paddle.float32)
        out = paddle.polar(abs, angle)
        self.assertTrue(out.type, 'complex64')

    def test_out_complex128(self):
        paddle.disable_static()
        abs = paddle.to_tensor(self.abs, dtype=paddle.float64)
        angle = paddle.to_tensor(self.angle, dtype=paddle.float64)
        out = paddle.polar(abs, angle)
        self.assertTrue(out.type, 'complex128')

    def test_empty_input_error(self):
        for place in self.place:
            paddle.disable_static(place)
            abs = paddle.to_tensor(self.abs)
            angle = paddle.to_tensor(self.angle)
            self.assertRaises(AttributeError, paddle.polar, None, angle)
            self.assertRaises(AttributeError, paddle.polar, abs, None)


class TestPolarAPI_ZeroSize(unittest.TestCase):
    def init_input(self):
        self.abs = np.random.random([0, 2])
        self.angle = np.array([np.pi / 2, 5 * np.pi / 4]).astype("float64")

    def setUp(self):
        self.init_input()
        self.place = get_places()

    def test_api_dygraph(self):
        def run(place):
            paddle.disable_static(place)
            abs = paddle.to_tensor(self.abs)
            abs.stop_gradient = False
            angle = paddle.to_tensor(self.angle)
            out1 = paddle.polar(abs, angle)

            out_ref1 = numpy_polar(self.abs, self.angle)
            np.testing.assert_allclose(out_ref1, out1.numpy(), rtol=1e-05)
            loss = paddle.sum(out1)
            loss.backward()
            np.testing.assert_allclose(abs.grad.shape, abs.shape)
            paddle.enable_static()

        for place in self.place:
            run(place)


class TestPolarAPI_ZeroSize2(TestPolarAPI_ZeroSize):
    def init_input(self):
        self.abs = np.random.random([0, 0])
        self.angle = np.random.random([0, 1])


class TestPolarOut(unittest.TestCase):
    def setUp(self):
        paddle.disable_static()
        self.shape = [3, 4]
        self.abs_np = np.random.rand(*self.shape).astype(np.float32)
        self.angle_np = np.random.rand(*self.shape).astype(np.float32)
        self.test_types = ["out"]

    def do_test(self, test_type):
        abs_t = paddle.to_tensor(self.abs_np, stop_gradient=False)
        angle_t = paddle.to_tensor(self.angle_np, stop_gradient=False)

        if test_type == 'raw':
            result = paddle.polar(abs_t, angle_t)
            result.real().mean().backward()
            return result, abs_t.grad, angle_t.grad
        elif test_type == 'out':
            out = paddle.empty(self.shape, dtype='complex64')
            out.stop_gradient = False
            paddle.polar(abs_t, angle_t, out=out)
            out.real().mean().backward()
            return out, abs_t.grad, angle_t.grad
        else:
            raise ValueError(f"Unknown test type: {test_type}")

    def test_out(self):
        out_std, abs_grad_std, angle_grad_std = self.do_test('raw')
        for test_type in self.test_types:
            out, abs_grad, angle_grad = self.do_test(test_type)
            np.testing.assert_allclose(out.numpy(), out_std.numpy(), rtol=1e-6)
            np.testing.assert_allclose(
                abs_grad.numpy(), abs_grad_std.numpy(), rtol=1e-6
            )
            np.testing.assert_allclose(
                angle_grad.numpy(), angle_grad_std.numpy(), rtol=1e-6
            )


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