# Copyright (c) 2021 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 random
import unittest

import numpy as np
from hybrid_parallel_mp_model import (
    SimpleDPNet,
    SimpleMPNet,
    TestDistMPTraining,
    parallel_matmul,
    set_random_seed,
)

import paddle
import paddle.distributed as dist
from paddle.distributed import fleet

vocab_size = 20
hidden_size = 10
inner_size = 8
output_size = 10
seq_length = 2
batch_size = 4


class SimpleMPMultimodalNet(SimpleMPNet):
    def forward(self, x, **kwargs):
        x = paddle.to_tensor(x)
        x = self.embedding(x)
        x = self.linear1(x)
        x = self.linear2(x)
        x = self.linear3(x)
        x = parallel_matmul(x, self.embedding.weight, False)
        return x


class SimpleDPMultimodalNet(SimpleDPNet):
    def forward(self, x, **kwargs):
        x = paddle.to_tensor(x)
        x = self.embedding(x)
        x = self.linear1(x)
        x = self.linear2(x)
        x = self.linear3(x)
        x = paddle.matmul(x, self.embedding.weight, transpose_y=True)
        return x


class TestMPBroadcastObj(TestDistMPTraining):
    def build_model_optimizer(self):
        hcg = fleet.get_hybrid_communicate_group()
        word_size = hcg.get_model_parallel_world_size()
        mp_id = hcg.get_model_parallel_rank()
        dp_id = hcg.get_data_parallel_rank()
        rank_id = dist.get_rank()
        set_random_seed(1024, dp_id, rank_id)

        np_fc1 = np.random.random_sample((hidden_size, inner_size))
        np_fc2 = np.random.random_sample((inner_size, hidden_size))

        model_a = SimpleMPMultimodalNet(
            vocab_size,
            hidden_size,
            inner_size,
            output_size,
            np_fc1,
            np_fc2,
            mp_id,
        )
        optimizer_a = self.build_optimizer(model_a)
        model_a = fleet.distributed_model(model_a)
        optimizer_a = fleet.distributed_optimizer(optimizer_a)

        model_b = SimpleDPMultimodalNet(
            vocab_size, hidden_size, inner_size, output_size, np_fc1, np_fc2
        )
        optimizer_b = self.build_optimizer(model_b)

        return model_a, optimizer_a, model_b, optimizer_b

    def train_batch(self, batch, model, optimizer, is_mp):
        img, text = batch
        output = model(img, text=text)
        loss = output.mean()
        loss.backward()  # do backward
        optimizer.step()  # update parameters
        optimizer.clear_grad()
        return loss

    def test_mp_model(self):
        (
            model_a,
            optimizer_a,
            model_b,
            optimizer_b,
        ) = self.build_model_optimizer()

        for _ in range(5):
            img = np.random.randint(
                0,
                vocab_size,
                (
                    batch_size,
                    seq_length,
                ),
            )
            text = [
                random.sample('zyxwvutsrqponmlkjihgfedcba', 5)
                for i in range(batch_size)
            ]
            batch = (img, text)

            loss_a = self.train_batch(batch, model_a, optimizer_a, True)
            loss_b = self.train_batch(batch, model_b, optimizer_b, False)

            np.testing.assert_allclose(
                loss_a.numpy(), loss_b.numpy(), rtol=1e-6
            )


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