#   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.
"""
FGSM tutorial on mnist using advbox tool.
FGSM method is non-targeted attack while FGSMT is targeted attack.
"""
import sys
sys.path.append("..")

import matplotlib.pyplot as plt
import numpy as np
import paddle.fluid as fluid
import paddle

from advbox.adversary import Adversary
from advbox.attacks.gradient_method import FGSM
from advbox.attacks.gradient_method import FGSMT
from advbox.models.paddle import PaddleModel
from tutorials.mnist_model import mnist_cnn_model


def main():
    """
    Advbox demo which demonstrate how to use advbox.
    """
    TOTAL_NUM = 500
    IMG_NAME = 'img'
    LABEL_NAME = 'label'

    img = fluid.layers.data(name=IMG_NAME, shape=[1, 28, 28], dtype='float32')
    # gradient should flow
    img.stop_gradient = False
    label = fluid.layers.data(name=LABEL_NAME, shape=[1], dtype='int64')
    logits = mnist_cnn_model(img)
    cost = fluid.layers.cross_entropy(input=logits, label=label)
    avg_cost = fluid.layers.mean(x=cost)

    # use CPU
    place = fluid.CPUPlace()
    # use GPU
    # place = fluid.CUDAPlace(0)
    exe = fluid.Executor(place)

    BATCH_SIZE = 1
    train_reader = paddle.batch(
        paddle.reader.shuffle(
            paddle.dataset.mnist.train(), buf_size=128 * 10),
        batch_size=BATCH_SIZE)

    test_reader = paddle.batch(
        paddle.reader.shuffle(
            paddle.dataset.mnist.test(), buf_size=128 * 10),
        batch_size=BATCH_SIZE)

    fluid.io.load_params(
        exe, "./mnist/", main_program=fluid.default_main_program())

    # advbox demo
    m = PaddleModel(
        fluid.default_main_program(),
        IMG_NAME,
        LABEL_NAME,
        logits.name,
        avg_cost.name, (-1, 1),
        channel_axis=1)
    attack = FGSM(m)
    # attack = FGSMT(m)
    attack_config = {"epsilons": 0.3}

    # use train data to generate adversarial examples
    total_count = 0
    fooling_count = 0
    for data in train_reader():
        total_count += 1
        adversary = Adversary(data[0][0], data[0][1])

        # FGSM non-targeted attack
        adversary = attack(adversary, **attack_config)

        # FGSMT targeted attack
        # tlabel = 0
        # adversary.set_target(is_targeted_attack=True, target_label=tlabel)
        # adversary = attack(adversary, **attack_config)

        if adversary.is_successful():
            fooling_count += 1
            print(
                'attack success, original_label=%d, adversarial_label=%d, count=%d'
                % (data[0][1], adversary.adversarial_label, total_count))
            # plt.imshow(adversary.target, cmap='Greys_r')
            # plt.show()
            # np.save('adv_img', adversary.target)
        else:
            print('attack failed, original_label=%d, count=%d' %
                  (data[0][1], total_count))

        if total_count >= TOTAL_NUM:
            print(
                "[TRAIN_DATASET]: fooling_count=%d, total_count=%d, fooling_rate=%f"
                % (fooling_count, total_count,
                   float(fooling_count) / total_count))
            break

    # use test data to generate adversarial examples
    total_count = 0
    fooling_count = 0
    for data in test_reader():
        total_count += 1
        adversary = Adversary(data[0][0], data[0][1])

        # FGSM non-targeted attack
        adversary = attack(adversary, **attack_config)

        # FGSMT targeted attack
        # tlabel = 0
        # adversary.set_target(is_targeted_attack=True, target_label=tlabel)
        # adversary = attack(adversary, **attack_config)

        if adversary.is_successful():
            fooling_count += 1
            print(
                'attack success, original_label=%d, adversarial_label=%d, count=%d'
                % (data[0][1], adversary.adversarial_label, total_count))
            # plt.imshow(adversary.target, cmap='Greys_r')
            # plt.show()
            # np.save('adv_img', adversary.target)
        else:
            print('attack failed, original_label=%d, count=%d' %
                  (data[0][1], total_count))

        if total_count >= TOTAL_NUM:
            print(
                "[TEST_DATASET]: fooling_count=%d, total_count=%d, fooling_rate=%f"
                % (fooling_count, total_count,
                   float(fooling_count) / total_count))
            break
    print("fgsm attack done")


if __name__ == '__main__':
    import paddle
    paddle.enable_static()
    main()