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
from config import IMAGE_SIZE, BASE_SIZE, CROP_MODE, MIN_CROPS, MAX_CROPS, PROMPT, TOKENIZER

def find_closest_aspect_ratio(aspect_ratio, target_ratios, width, height, image_size):
    best_ratio_diff = float('inf')
    best_ratio = (1, 1)
    area = width * height
    for ratio in target_ratios:
        target_aspect_ratio = ratio[0] / ratio[1]
        ratio_diff = abs(aspect_ratio - target_aspect_ratio)
        if ratio_diff < best_ratio_diff:
            best_ratio_diff = ratio_diff
            best_ratio = ratio
        elif ratio_diff == best_ratio_diff:
            if area > 0.5 * image_size * image_size * ratio[0] * ratio[1]:
                best_ratio = ratio
    # print(f'width: {width}, height: {height}, best_ratio: {best_ratio}')
    return best_ratio


def count_tiles(orig_width, orig_height, min_num=MIN_CROPS, max_num=MAX_CROPS, image_size=640, use_thumbnail=False):
    aspect_ratio = orig_width / orig_height

    # calculate the existing image aspect ratio
    target_ratios = set(
        (i, j) for n in range(min_num, max_num + 1) for i in range(1, n + 1) for j in range(1, n + 1) if
        i * j <= max_num and i * j >= min_num)
    # print(target_ratios)
    target_ratios = sorted(target_ratios, key=lambda x: x[0] * x[1])

    # find the closest aspect ratio to the target
    target_aspect_ratio = find_closest_aspect_ratio(
        aspect_ratio, target_ratios, orig_width, orig_height, image_size)

    return target_aspect_ratio


def dynamic_preprocess(image, min_num=MIN_CROPS, max_num=MAX_CROPS, image_size=640, use_thumbnail=False):
    orig_width, orig_height = image.size
    aspect_ratio = orig_width / orig_height

    # calculate the existing image aspect ratio
    target_ratios = set(
        (i, j) for n in range(min_num, max_num + 1) for i in range(1, n + 1) for j in range(1, n + 1) if
        i * j <= max_num and i * j >= min_num)
    # print(target_ratios)
    target_ratios = sorted(target_ratios, key=lambda x: x[0] * x[1])

    # find the closest aspect ratio to the target
    target_aspect_ratio = find_closest_aspect_ratio(
        aspect_ratio, target_ratios, orig_width, orig_height, image_size)

    # print(target_aspect_ratio)
    # calculate the target width and height
    target_width = image_size * target_aspect_ratio[0]
    target_height = image_size * target_aspect_ratio[1]
    blocks = target_aspect_ratio[0] * target_aspect_ratio[1]

    # resize the image
    resized_img = image.resize((target_width, target_height))
    processed_images = []
    for i in range(blocks):
        box = (
            (i % (target_width // image_size)) * image_size,
            (i // (target_width // image_size)) * image_size,
            ((i % (target_width // image_size)) + 1) * image_size,
            ((i // (target_width // image_size)) + 1) * image_size
        )
        # split the image
        split_img = resized_img.crop(box)
        processed_images.append(split_img)
    assert len(processed_images) == blocks
    if use_thumbnail and len(processed_images) != 1:
        thumbnail_img = image.resize((image_size, image_size))
        processed_images.append(thumbnail_img)
    return processed_images, target_aspect_ratio





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

    def __init__(
        self,
        tokenizer: LlamaTokenizerFast = TOKENIZER,
        candidate_resolutions: Tuple[Tuple[int, int]] = [[1024, 1024]],
        patch_size: int = 16,
        downsample_ratio: int = 4,
        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 # placeholder no use
        self.image_size = IMAGE_SIZE
        self.base_size = BASE_SIZE
        # self.patch_size = patch_size
        self.patch_size = 16 
        self.image_mean = image_mean
        self.image_std = image_std
        self.normalize = normalize
        # self.downsample_ratio = downsample_ratio
        self.downsample_ratio = 4

        self.image_transform = ImageTransform(mean=image_mean, std=image_std, normalize=normalize)


        self.tokenizer = tokenizer
        # self.tokenizer = add_special_token(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 self.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}

        # special_tokens = ['<image>','<|ref|>', '<|/ref|>', '<|det|>', '<|/det|>', '<|grounding|>', '<td>', '</td>', '<tr>', '</tr>']
        # 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,
        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

        input_ids, pixel_values, images_crop, images_seq_mask, images_spatial_crop, num_image_tokens, _ = images[0]


        return {
            "input_ids": input_ids,
            "pixel_values": pixel_values,
            "images_crop": images_crop,
            "images_seq_mask": images_seq_mask,
            "images_spatial_crop": images_spatial_crop,
            "num_image_tokens": num_image_tokens,
        }


        # prepare = BatchFeature(
        #     data=dict(
        #         input_ids=input_ids,
        #         pixel_values=pixel_values,
        #         images_crop = images_crop,
        #         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,
        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."""

        # print(conversation)
        conversation = PROMPT
        assert conversation.count(self.image_token) == len(images)
        text_splits = conversation.split(self.image_token)
        images_list, images_crop_list, images_seq_mask, images_spatial_crop = [], [], [], []
        image_shapes = []
        num_image_tokens = []
        tokenized_str = []
        # print('image: ', len(images))
        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

            image_shapes.append(image.size)

            if image.size[0] <= 640 and image.size[1] <= 640:
                crop_ratio = [1, 1]
            else:
                if cropping:
                    # print('image-size: ', image.size)
                    # best_width, best_height = select_best_resolution(image.size, self.candidate_resolutions)
                    # print('image ', image.size)
                    # print('open_size:', image.size)
                    images_crop_raw, crop_ratio = dynamic_preprocess(image, image_size=IMAGE_SIZE)
                    # print('crop_ratio: ', crop_ratio)
                else:
                    # best_width, best_height = self.image_size, self.image_size
                    crop_ratio = [1, 1]
            # print(image.size, (best_width, best_height)) # check the select_best_resolutions func

            # print(crop_ratio)
            """process the global view"""

            # if cropping
            if self.image_size <= 640 and not cropping:
                # print('directly resize')
                image = image.resize((self.image_size, self.image_size))

            global_view = ImageOps.pad(image, (self.base_size, self.base_size),
                                    color=tuple(int(x * 255) for x in self.image_transform.mean))
            images_list.append(self.image_transform(global_view))

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




            if num_width_tiles > 1 or num_height_tiles > 1:
                """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_crop_list.append(
                #             self.image_transform(local_view.crop((j, i, j + self.image_size, i + self.image_size))))
                for i in range(len(images_crop_raw)):
                    images_crop_list.append(self.image_transform(images_crop_raw[i]))

            # """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))))

            # """add image tokens"""
            """add image tokens"""
            num_queries = math.ceil((self.image_size // self.patch_size) / self.downsample_ratio)
            num_queries_base = math.ceil((self.base_size // self.patch_size) / self.downsample_ratio)


            tokenized_image = ([self.image_token_id] * num_queries_base + [self.image_token_id]) * num_queries_base
            tokenized_image += [self.image_token_id]
            if num_width_tiles > 1 or num_height_tiles > 1:
                tokenized_image += ([self.image_token_id] * (num_queries * num_width_tiles) + [self.image_token_id]) * (
                            num_queries * num_height_tiles)
            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)}"
        


        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

        inference_mode = True

        if inference_mode:
            # Remove the ending 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.base_size, self.base_size))
            images_spatial_crop = torch.zeros((1, 1), dtype=torch.long)
            images_crop = torch.zeros((1, 3, self.image_size, self.image_size)).unsqueeze(0)
        else:
            pixel_values = torch.stack(images_list, dim=0)
            images_spatial_crop = torch.tensor(images_spatial_crop, dtype=torch.long)
            if images_crop_list:
                images_crop = torch.stack(images_crop_list, dim=0).unsqueeze(0)
            else:
                images_crop = torch.zeros((1, 3, self.image_size, self.image_size)).unsqueeze(0)

        input_ids = input_ids.unsqueeze(0)

        
        return [[input_ids, pixel_values, images_crop, images_seq_mask, images_spatial_crop, num_image_tokens, image_shapes]]


AutoProcessor.register("DeepseekVLV2Processor", DeepseekOCRProcessor)
