# SPDX-License-Identifier: Apache-2.0

# yapf: disable
# ruff: noqa: E501
# coding=utf-8
# adapted from https://github.com/deepseek-ai/DeepSeek-VL2/blob/ff23960c5cf9e6874b44be38af930cfb0ccbb620/deepseek_vl2/models/processing_deepseek_vl_v2.py
# Copyright (c) 2023-2024 DeepSeek.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
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# the Software, and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
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#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

import math
from typing import List, Tuple

import torch
import torchvision.transforms as T
from PIL import Image, ImageOps
from transformers import AutoProcessor, BatchFeature, LlamaTokenizerFast
from transformers.processing_utils import ProcessorMixin


class ImageTransform:

    def __init__(self,
                 mean: Tuple[float, float, float] = (0.5, 0.5, 0.5),
                 std: Tuple[float, float, float] = (0.5, 0.5, 0.5),
                 normalize: bool = True):
        self.mean = mean
        self.std = std
        self.normalize = normalize

        transform_pipelines = [T.ToTensor()]

        if normalize:
            transform_pipelines.append(T.Normalize(mean, std))

        self.transform = T.Compose(transform_pipelines)

    def __call__(self, pil_img: Image.Image):
        x = self.transform(pil_img)
        return x


class DeepseekVLV2Processor(ProcessorMixin):
    tokenizer_class = ("LlamaTokenizer", "LlamaTokenizerFast")
    attributes = ["tokenizer"]

    def __init__(
        self,
        tokenizer: LlamaTokenizerFast,
        candidate_resolutions: Tuple[Tuple[int, int]],
        patch_size: int,
        downsample_ratio: int,
        image_mean: Tuple[float, float, float] = (0.5, 0.5, 0.5),
        image_std: Tuple[float, float, float] = (0.5, 0.5, 0.5),
        normalize: bool = True,
        image_token: str = "<image>",
        pad_token: str = "<｜▁pad▁｜>",
        add_special_token: bool = False,
        sft_format: str = "deepseek",
        mask_prompt: bool = True,
        ignore_id: int = -100,
        **kwargs,
    ):

        self.candidate_resolutions = candidate_resolutions
        self.image_size = candidate_resolutions[0][0]
        self.patch_size = patch_size
        self.image_mean = image_mean
        self.image_std = image_std
        self.normalize = normalize
        self.downsample_ratio = downsample_ratio

        self.image_transform = ImageTransform(mean=image_mean, std=image_std, normalize=normalize)
        self.tokenizer = tokenizer
        self.tokenizer.padding_side = 'left'  # must set this，padding side with make a difference in batch inference

        # add the pad_token as special token to use 'tokenizer.pad_token' and 'tokenizer.pad_token_id'
        if tokenizer.pad_token is None:
            self.tokenizer.add_special_tokens({'pad_token': pad_token})

        # add image token
        image_token_id = self.tokenizer.vocab.get(image_token)
        if image_token_id is None:
            special_tokens = [image_token]
            special_tokens_dict = {"additional_special_tokens": special_tokens}
            self.tokenizer.add_special_tokens(special_tokens_dict)
        self.image_token_id = self.tokenizer.vocab.get(image_token)

        # add five special tokens for grounding-related tasks
        # <|ref|>, <|/ref|>, <|det|>, <|/det|>, <|grounding|>
        special_tokens = ['<|ref|>', '<|/ref|>', '<|det|>', '<|/det|>', '<|grounding|>']
        special_tokens_dict = {"additional_special_tokens": special_tokens}
        self.tokenizer.add_special_tokens(special_tokens_dict)

        # add special tokens for SFT data
        special_tokens = ["<|User|>", "<|Assistant|>"]
        special_tokens_dict = {"additional_special_tokens": special_tokens}
        self.tokenizer.add_special_tokens(special_tokens_dict)

        self.image_token = image_token
        self.pad_token = pad_token
        self.add_special_token = add_special_token
        self.sft_format = sft_format
        self.mask_prompt = mask_prompt
        self.ignore_id = ignore_id

        super().__init__(
            tokenizer,
            **kwargs,
        )

    def select_best_resolution(self, image_size):
        # used for cropping
        original_width, original_height = image_size
        best_fit = None
        max_effective_resolution = 0
        min_wasted_resolution = float("inf")

        for width, height in self.candidate_resolutions:
            scale = min(width / original_width, height / original_height)
            downscaled_width, downscaled_height = int(
                original_width * scale), int(original_height * scale)
            effective_resolution = min(downscaled_width * downscaled_height,
                                       original_width * original_height)
            wasted_resolution = (width * height) - effective_resolution

            if effective_resolution > max_effective_resolution or (
                    effective_resolution == max_effective_resolution
                    and wasted_resolution < min_wasted_resolution):
                max_effective_resolution = effective_resolution
                min_wasted_resolution = wasted_resolution
                best_fit = (width, height)

        return best_fit

    @property
    def bos_id(self):
        return self.tokenizer.bos_token_id

    @property
    def eos_id(self):
        return self.tokenizer.eos_token_id

    @property
    def pad_id(self):
        return self.tokenizer.pad_token_id

    def encode(self, text: str, bos: bool = True, eos: bool = False):
        t = self.tokenizer.encode(text, add_special_tokens=False)

        if bos:
            t = [self.bos_id] + t
        if eos:
            t = t + [self.eos_id]

        return t

    def decode(self, t: List[int], **kwargs) -> str:
        return self.tokenizer.decode(t, **kwargs)

    def process_one(
        self,
        prompt: str,
        images: List[Image.Image],
        inference_mode: bool = True,
        **kwargs,
    ):
        """

        Args:
            prompt (str): the formatted prompt;
            conversations (List[Dict]): conversations with a list of messages;
            images (List[ImageType]): the list of images;
            inference_mode (bool): if True, then remove the last eos token;
            system_prompt (str): the system prompt;
            **kwargs:

        Returns:
            outputs (BaseProcessorOutput): the output of the processor,
                - input_ids (torch.LongTensor): [N + image tokens]
                - target_ids (torch.LongTensor): [N + image tokens]
                - pixel_values (torch.FloatTensor): [n_patches, 3, H, W]
                - image_id (int): the id of the image token
                - num_image_tokens (List[int]): the number of image tokens
        """

        assert (prompt is not None and images is not None
                ), "prompt and images must be used at the same time."

        sft_format = prompt
        tokenized_str, images_list, images_seq_mask, images_spatial_crop, num_image_tokens = self.tokenize_with_images(
            sft_format, images, bos=True, eos=True, cropping=len(images) <= 2)
        masked_tokenized_str = []
        for token_index in tokenized_str:
            if token_index != self.image_token_id:
                masked_tokenized_str.append(token_index)
            else:
                masked_tokenized_str.append(self.ignore_id)

        assert len(tokenized_str) == len(images_seq_mask) == len(masked_tokenized_str), \
            (f"tokenized_str's length {len(tokenized_str)}, input_ids' length {len(masked_tokenized_str)}, "
             f"imags_seq_mask's length {len(images_seq_mask)}, are not equal")

        input_ids = torch.LongTensor(tokenized_str)
        target_ids = torch.LongTensor(masked_tokenized_str)
        images_seq_mask = torch.tensor(images_seq_mask, dtype=torch.bool)

        # set input_ids < 0 | input_ids == self.image_token_id as ignore_id
        target_ids[(input_ids < 0) |
                   (input_ids == self.image_token_id)] = self.ignore_id
        input_ids[input_ids < 0] = self.pad_id

        if inference_mode:
            # 去掉结尾的eos token
            assert input_ids[-1] == self.eos_id
            input_ids = input_ids[:-1]
            target_ids = target_ids[:-1]
            images_seq_mask = images_seq_mask[:-1]

        if len(images_list) == 0:
            pixel_values = torch.zeros((1, 3, self.image_size, self.image_size))
            images_spatial_crop = torch.zeros((1, 2), dtype=torch.long)
        else:
            pixel_values = torch.stack(images_list, dim=0)
            images_spatial_crop = torch.tensor(images_spatial_crop, dtype=torch.long)

        input_ids = input_ids.unsqueeze(0)

        prepare = BatchFeature(
            data=dict(
                input_ids=input_ids,
                pixel_values=pixel_values,
                images_seq_mask=images_seq_mask,
                images_spatial_crop=images_spatial_crop,
                num_image_tokens=num_image_tokens,
            ),
            tensor_type="pt",
        )
        return prepare

    def __call__(
        self,
        *,
        prompt: str,
        images: List[Image.Image],
        inference_mode: bool = True,
        **kwargs,
    ):
        """

        Args:
            prompt (str): the formatted prompt;
            images (List[ImageType]): the list of images;
            inference_mode (bool): if True, then remove the last eos token;
            **kwargs:

        Returns:
            outputs (BaseProcessorOutput): the output of the processor,
                - input_ids (torch.LongTensor): [N + image tokens]
                - images (torch.FloatTensor): [n_images, 3, H, W]
                - image_id (int): the id of the image token
                - num_image_tokens (List[int]): the number of image tokens
        """

        prepare = self.process_one(
            prompt=prompt,
            images=images,
            inference_mode=inference_mode,
        )

        return prepare

    def tokenize_with_images(
        self,
        conversation: str,
        images: List[Image.Image],
        bos: bool = True,
        eos: bool = True,
        cropping: bool = True,
    ):
        """Tokenize text with <image> tags."""
        assert conversation.count(self.image_token) == len(images)
        text_splits = conversation.split(self.image_token)
        images_list, images_seq_mask, images_spatial_crop = [], [], []
        num_image_tokens = []
        tokenized_str = []
        for text_sep, image in zip(text_splits, images):
            """encode text_sep"""
            tokenized_sep = self.encode(text_sep, bos=False, eos=False)
            tokenized_str += tokenized_sep
            images_seq_mask += [False] * len(tokenized_sep)

            """select best resolution for anyres"""
            if cropping:
                best_width, best_height = self.select_best_resolution(image.size)
            else:
                best_width, best_height = self.image_size, self.image_size

            """process the global view"""
            global_view = ImageOps.pad(image, (self.image_size, self.image_size),
                                       color=tuple(int(x * 255) for x in self.image_transform.mean))
            images_list.append(self.image_transform(global_view))

            """process the local views"""
            local_view = ImageOps.pad(image, (best_width, best_height),
                                      color=tuple(int(x * 255) for x in self.image_transform.mean))
            for i in range(0, best_height, self.image_size):
                for j in range(0, best_width, self.image_size):
                    images_list.append(
                        self.image_transform(local_view.crop((j, i, j + self.image_size, i + self.image_size))))

            """record height / width crop num"""
            num_width_tiles, num_height_tiles = best_width // self.image_size, best_height // self.image_size
            images_spatial_crop.append([num_width_tiles, num_height_tiles])

            """add image tokens"""
            h = w = math.ceil((self.image_size // self.patch_size) / self.downsample_ratio)
            # global views tokens h * (w + 1), 1 is for line separator
            tokenized_image = [self.image_token_id] * h * (w + 1)
            # add a separator between global and local views
            tokenized_image += [self.image_token_id]
            # local views tokens, (num_height_tiles * h) * (num_width_tiles * w + 1)
            tokenized_image += [self.image_token_id] * (num_height_tiles * h) * (num_width_tiles * w + 1)

            tokenized_str += tokenized_image
            images_seq_mask += [True] * len(tokenized_image)
            num_image_tokens.append(len(tokenized_image))

        """process the last text split"""
        tokenized_sep = self.encode(text_splits[-1], bos=False, eos=False)
        tokenized_str += tokenized_sep
        images_seq_mask += [False] * len(tokenized_sep)

        """add the bos and eos tokens"""
        if bos:
            tokenized_str = [self.bos_id] + tokenized_str
            images_seq_mask = [False] + images_seq_mask
        if eos:
            tokenized_str = tokenized_str + [self.eos_id]
            images_seq_mask = images_seq_mask + [False]

        assert len(tokenized_str) == len(
            images_seq_mask), f"tokenize_with_images func: tokenized_str's length {len(tokenized_str)} is not equal to imags_seq_mask's length {len(images_seq_mask)}"

        return tokenized_str, images_list, images_seq_mask, images_spatial_crop, num_image_tokens


AutoProcessor.register("DeepseekVLV2Processor", DeepseekVLV2Processor)
