# Copyright 2022 HuggingFace Inc.
#
# 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

from transformers.image_utils import SizeDict
from transformers.testing_utils import require_torch, require_vision
from transformers.utils import is_torch_available

from ...test_image_processing_common import ImageProcessingTester, ImageProcessingTestMixin


if is_torch_available():
    import torch


class GotOcr2ImageProcessingTester(ImageProcessingTester):
    def __init__(self, **kwargs):
        # Image processor init kwargs
        kwargs.setdefault("size", {"height": 20, "width": 20})

        super().__init__(**kwargs)


@require_torch
@require_vision
class GotOcr2ProcessingTest(ImageProcessingTestMixin, unittest.TestCase):
    image_processor_tester_class = GotOcr2ImageProcessingTester

    def test_backends_equivalence_crop_to_patches(self):
        if len(self.image_processing_classes) < 2:
            self.skipTest(reason="Skipping backends equivalence test as there are less than 2 backends")

        dummy_image = self.image_processor_tester.prepare_image_inputs(equal_resolution=False, torchify=True)[0]

        encodings = {}
        for backend_name, image_processing_class in self.image_processing_classes.items():
            image_processor = image_processing_class(**self.image_processor_dict, crop_to_patches=True)
            encodings[backend_name] = image_processor(dummy_image, return_tensors="pt")

        backend_names = list(encodings.keys())
        reference_backend = backend_names[0]
        reference_num_patches = encodings[reference_backend].num_patches
        reference_pixel_values = encodings[reference_backend].pixel_values

        for backend_name in backend_names[1:]:
            torch.testing.assert_close(reference_num_patches, encodings[backend_name].num_patches)
            self._assert_tensors_equivalence(reference_pixel_values, encodings[backend_name].pixel_values)

    def test_backends_equivalence_batched_crop_to_patches(self):
        if len(self.image_processing_classes) < 2:
            self.skipTest(reason="Skipping backends equivalence test as there are less than 2 backends")

        # Prepare image inputs so that we have two groups of images with equal resolution with a group of images with
        # different resolutions in between
        dummy_images = self.image_processor_tester.prepare_image_inputs(equal_resolution=True, torchify=True)
        dummy_images += self.image_processor_tester.prepare_image_inputs(equal_resolution=False, torchify=True)
        dummy_images += self.image_processor_tester.prepare_image_inputs(equal_resolution=True, torchify=True)

        encodings = {}
        for backend_name, image_processing_class in self.image_processing_classes.items():
            image_processor = image_processing_class(**self.image_processor_dict, crop_to_patches=True)
            encodings[backend_name] = image_processor(dummy_images, return_tensors="pt")

        backend_names = list(encodings.keys())
        reference_backend = backend_names[0]
        reference_num_patches = encodings[reference_backend].num_patches
        reference_pixel_values = encodings[reference_backend].pixel_values

        for backend_name in backend_names[1:]:
            torch.testing.assert_close(reference_num_patches, encodings[backend_name].num_patches)
            self._assert_tensors_equivalence(reference_pixel_values, encodings[backend_name].pixel_values)

    def test_crop_to_patches(self):
        for backend_name, image_processing_class in self.image_processing_classes.items():
            image_processor = image_processing_class(**self.image_processor_dict)
            if backend_name == "pil":
                # PIL backend processes single images
                image = self.image_processor_tester.prepare_image_inputs(equal_resolution=True, numpify=True)[0]
                processed_images = image_processor.crop_image_to_patches(
                    image,
                    min_patches=1,
                    max_patches=6,
                    use_thumbnail=True,
                    patch_size=SizeDict(height=20, width=20),
                )
                self.assertEqual(len(processed_images), 5)
                self.assertEqual(processed_images[0].shape[:2], (20, 20))
            else:
                # Torchvision backend processes batches
                image = self.image_processor_tester.prepare_image_inputs(equal_resolution=True, torchify=True)[0]
                processed_images = image_processor.crop_image_to_patches(
                    image.unsqueeze(0),
                    min_patches=1,
                    max_patches=6,
                    use_thumbnail=True,
                    patch_size=SizeDict(height=20, width=20),
                )
                self.assertEqual(len(processed_images[0]), 5)
                self.assertEqual(processed_images.shape[-2:], (20, 20))

    def test_get_num_patches_without_images(self):
        for image_processing_class in self.image_processing_classes.values():
            image_processing = image_processing_class(**self.image_processor_dict)
            num_patches = image_processing.get_number_of_image_patches(height=100, width=100, images_kwargs={})
            self.assertEqual(num_patches, 1)

            num_patches = image_processing.get_number_of_image_patches(
                height=300, width=500, images_kwargs={"crop_to_patches": False}
            )
            self.assertEqual(num_patches, 1)

            num_patches = image_processing.get_number_of_image_patches(
                height=20, width=20, images_kwargs={"crop_to_patches": True}
            )
            self.assertEqual(num_patches, 1)

            num_patches = image_processing.get_number_of_image_patches(
                height=60, width=60, images_kwargs={"crop_to_patches": True}
            )
            self.assertEqual(num_patches, 10)

            num_patches = image_processing.get_number_of_image_patches(
                height=100, width=100, images_kwargs={"crop_to_patches": True}
            )
            self.assertEqual(num_patches, 10)

            num_patches = image_processing.get_number_of_image_patches(
                height=100, width=100, images_kwargs={"crop_to_patches": True, "max_patches": 200}
            )
            self.assertEqual(num_patches, 50)