# coding=utf-8
# Copyright 2024 The HuggingFace Inc. team.
#
# 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
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# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
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# See the License for the specific language governing permissions and
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"""
Processor class for Pixtral.
"""

from typing import List, Union

from ...feature_extraction_utils import BatchFeature
from ...image_utils import ImageInput, is_valid_image, load_image
from ...processing_utils import ProcessingKwargs, ProcessorMixin, Unpack, _validate_images_text_input_order
from ...tokenization_utils_base import PreTokenizedInput, TextInput
from ...utils import is_torch_device, is_torch_dtype, is_torch_tensor, logging, requires_backends


logger = logging.get_logger(__name__)


class PixtralProcessorKwargs(ProcessingKwargs, total=False):
    _defaults = {
        "text_kwargs": {
            "padding": False,
        },
        "images_kwargs": {},
        "common_kwargs": {
            "return_tensors": "pt",
        },
    }


# Copied from transformers.models.idefics2.processing_idefics2.is_url
def is_url(val) -> bool:
    return isinstance(val, str) and val.startswith("http")


# Copied from transformers.models.idefics2.processing_idefics2.is_image_or_image_url
def is_image_or_image_url(elem):
    return is_url(elem) or is_valid_image(elem)


# Copied from transformers.models.pixtral.image_processing_pixtral.BatchMixFeature
class BatchMixFeature(BatchFeature):
    def to(self, *args, **kwargs) -> "BatchMixFeature":
        """
        Send all values to device by calling `v.to(*args, **kwargs)` (PyTorch only). This should support casting in
        different `dtypes` and sending the `BatchFeature` to a different `device`.

        Args:
            args (`Tuple`):
                Will be passed to the `to(...)` function of the tensors.
            kwargs (`Dict`, *optional*):
                Will be passed to the `to(...)` function of the tensors.

        Returns:
            [`BatchFeature`]: The same instance after modification.
        """
        requires_backends(self, ["torch"])
        import torch  # noqa

        new_data = {}
        device = kwargs.get("device")
        # Check if the args are a device or a dtype
        if device is None and len(args) > 0:
            # device should be always the first argument
            arg = args[0]
            if is_torch_dtype(arg):
                # The first argument is a dtype
                pass
            elif isinstance(arg, str) or is_torch_device(arg) or isinstance(arg, int):
                device = arg
            else:
                # it's something else
                raise ValueError(f"Attempting to cast a BatchFeature to type {str(arg)}. This is not supported.")
        # We cast only floating point tensors to avoid issues with tokenizers casting `LongTensor` to `FloatTensor`
        for k, v in self.items():
            # check if v is a floating point
            if isinstance(v, list):
                new_data[k] = [
                    element.to(*args, **kwargs) for sample in v for element in sample if is_torch_tensor(element)
                ]
            elif isinstance(v, torch.Tensor) and torch.is_floating_point(v):
                # cast and send to device
                new_data[k] = v.to(*args, **kwargs)
            elif isinstance(v, torch.Tensor) and device is not None:
                new_data[k] = v.to(device=device)
            else:
                new_data[k] = v
        self.data = new_data
        return self


class PixtralProcessor(ProcessorMixin):
    r"""
    Constructs a Pixtral processor which wraps a Pixtral image processor and a Pixtral tokenizer into a single processor.

    [`PixtralProcessor`] offers all the functionalities of [`CLIPImageProcessor`] and [`LlamaTokenizerFast`]. See the
    [`~PixtralProcessor.__call__`] and [`~PixtralProcessor.decode`] for more information.

    Args:
        image_processor ([`PixtralImageProcessor`], *optional*):
            The image processor is a required input.
        tokenizer ([`LlamaTokenizerFast`], *optional*):
            The tokenizer is a required input.
        patch_size (`int`, *optional*, defaults to 16):
            Patch size from the vision tower.
        chat_template (`str`, *optional*): A Jinja template which will be used to convert lists of messages
            in a chat into a tokenizable string.
        image_token (`str`, *optional*, defaults to `"[IMG]"`):
            Special token used to denote image location.
        image_break_token (`str`, *optional*, defaults to `"[IMG_BREAK]"`):
            Special token used to denote the end of a line of pixels in an image.
        image_end_token (`str`, *optional*, defaults to `"[IMG_END]"`):
            Special token used to denote the end of an image input.
    """

    attributes = ["image_processor", "tokenizer"]
    valid_kwargs = [
        "chat_template",
        "patch_size",
        "image_token",
        "image_break_token",
        "image_end_token",
    ]
    image_processor_class = "AutoImageProcessor"
    tokenizer_class = "AutoTokenizer"

    def __init__(
        self,
        image_processor=None,
        tokenizer=None,
        patch_size: int = 16,
        chat_template=None,
        image_token="[IMG]",  # set the default and let users change if they have peculiar special tokens in rare cases
        image_break_token="[IMG_BREAK]",
        image_end_token="[IMG_END]",
        **kwargs,
    ):
        self.patch_size = patch_size
        self.image_token = image_token
        self.image_break_token = image_break_token
        self.image_end_token = image_end_token
        super().__init__(image_processor, tokenizer, chat_template=chat_template)

    def __call__(
        self,
        images: ImageInput = None,
        text: Union[TextInput, PreTokenizedInput, List[TextInput], List[PreTokenizedInput]] = None,
        audio=None,
        videos=None,
        **kwargs: Unpack[PixtralProcessorKwargs],
    ) -> BatchMixFeature:
        """
        Main method to prepare for the model one or several sequences(s) and image(s). This method forwards the `text`
        and `kwargs` arguments to LlamaTokenizerFast's [`~LlamaTokenizerFast.__call__`] if `text` is not `None` to encode
        the text. To prepare the image(s), this method forwards the `images` and `kwrags` arguments to
        CLIPImageProcessor's [`~CLIPImageProcessor.__call__`] if `images` is not `None`. Please refer to the doctsring
        of the above two methods for more information.

        Args:
            images (`PIL.Image.Image`, `np.ndarray`, `torch.Tensor`, `List[PIL.Image.Image]`, `List[np.ndarray]`, `List[torch.Tensor]`):
                The image or batch of images to be prepared. Each image can be a PIL image, NumPy array or PyTorch
                tensor. Both channels-first and channels-last formats are supported.
            text (`str`, `List[str]`, `List[List[str]]`):
                The sequence or batch of sequences to be encoded. Each sequence can be a string or a list of strings
                (pretokenized string). If the sequences are provided as list of strings (pretokenized), you must set
                `is_split_into_words=True` (to lift the ambiguity with a batch of sequences).
            return_tensors (`str` or [`~utils.TensorType`], *optional*):
                If set, will return tensors of a particular framework. Acceptable values are:

                - `'tf'`: Return TensorFlow `tf.constant` objects.
                - `'pt'`: Return PyTorch `torch.Tensor` objects.
                - `'np'`: Return NumPy `np.ndarray` objects.
                - `'jax'`: Return JAX `jnp.ndarray` objects.

        Returns:
            [`BatchFeature`]: A [`BatchFeature`] with the following fields:

            - **input_ids** -- List of token ids to be fed to a model. Returned when `text` is not `None`.
            - **attention_mask** -- List of indices specifying which tokens should be attended to by the model (when
              `return_attention_mask=True` or if *"attention_mask"* is in `self.model_input_names` and if `text` is not
            `None`).
            - **pixel_values** -- Pixel values to be fed to a model. Returned when `images` is not `None`.
        """
        # check if images and text inputs are reversed for BC
        images, text = _validate_images_text_input_order(images, text)

        output_kwargs = self._merge_kwargs(
            PixtralProcessorKwargs,
            tokenizer_init_kwargs=self.tokenizer.init_kwargs,
            **kwargs,
        )

        if images is not None:
            if is_image_or_image_url(images):
                images = [[images]]
            elif isinstance(images, list) and is_image_or_image_url(images[0]):
                if isinstance(text, list):
                    images = [[im] for im in images]
                else:
                    images = [images]
            elif isinstance(images, list) and isinstance(images[0], list) and is_image_or_image_url(images[0][0]):
                pass
            else:
                raise ValueError(
                    "Invalid input images. Please provide a single image, a list of images, or a list of lists of images."
                )
            images = [[load_image(im) for im in sample] for sample in images]
            image_inputs = self.image_processor(images, patch_size=self.patch_size, **output_kwargs["images_kwargs"])
        else:
            image_inputs = {}

        if isinstance(text, str):
            text = [text]
        elif not isinstance(text, list) and not isinstance(text[0], str):
            raise ValueError("Invalid input text. Please provide a string, or a list of strings")

        # try to expand inputs in processing if we have the necessary parts
        prompt_strings = text
        if image_inputs.get("pixel_values") is not None:
            # Replace the image token with the expanded image token sequence
            images = image_inputs["pixel_values"]
            image_sizes = image_inputs.pop("image_sizes")
            prompt_strings = []

            for sample_images, sample_image_sizes, sample in zip(images, image_sizes, text):
                replace_strings = []
                # First calculate the number of tokens needed for each image and put in a placeholder
                for image, image_size in zip(sample_images, sample_image_sizes):
                    height, width = image_size
                    num_height_tokens = height // self.patch_size
                    num_width_tokens = width // self.patch_size
                    replace_tokens = [
                        [self.image_token] * num_width_tokens + [self.image_break_token]
                    ] * num_height_tokens
                    # Flatten list
                    replace_tokens = [item for sublist in replace_tokens for item in sublist]
                    replace_tokens[-1] = self.image_end_token
                    replace_str = "".join(replace_tokens)
                    replace_strings.append(replace_str)
                    sample = sample.replace(self.image_token, "<placeholder>", 1)

                while "<placeholder>" in sample:
                    replace_str = replace_strings.pop(0)
                    sample = sample.replace("<placeholder>", replace_str, 1)
                prompt_strings.append(sample)

        text_inputs = self.tokenizer(prompt_strings, **output_kwargs["text_kwargs"])
        return BatchMixFeature(data={**text_inputs, **image_inputs})

    # Copied from transformers.models.clip.processing_clip.CLIPProcessor.batch_decode with CLIP->Llama
    def batch_decode(self, *args, **kwargs):
        """
        This method forwards all its arguments to LlamaTokenizerFast's [`~PreTrainedTokenizer.batch_decode`]. Please
        refer to the docstring of this method for more information.
        """
        return self.tokenizer.batch_decode(*args, **kwargs)

    # Copied from transformers.models.clip.processing_clip.CLIPProcessor.decode with CLIP->Llama
    def decode(self, *args, **kwargs):
        """
        This method forwards all its arguments to LlamaTokenizerFast's [`~PreTrainedTokenizer.decode`]. Please refer to
        the docstring of this method for more information.
        """
        return self.tokenizer.decode(*args, **kwargs)

    @property
    # Copied from transformers.models.clip.processing_clip.CLIPProcessor.model_input_names
    def model_input_names(self):
        tokenizer_input_names = self.tokenizer.model_input_names
        image_processor_input_names = self.image_processor.model_input_names
        return list(dict.fromkeys(tokenizer_input_names + image_processor_input_names))
