import re
from datetime import timedelta
from multiprocessing import context
from typing import List, Optional, Sequence, Tuple, Union

import numpy as np
import torch
import torchvision.transforms as transforms
from accelerate import Accelerator, DistributedType, InitProcessGroupKwargs
from accelerate.state import AcceleratorState
from PIL import Image
from tqdm import tqdm
from transformers import AutoModel, AutoTokenizer

from lmms_eval import utils
from lmms_eval.api.instance import Instance
from lmms_eval.api.model import lmms
from lmms_eval.api.registry import register_model
from lmms_eval.utils import stop_sequences_criteria

pattern = re.compile(r"[A-Z]")

from loguru import logger as eval_logger

meta_instruction = """You are an AI assistant whose name is InternLM-XComposer (浦语·灵笔).
- InternLM-XComposer (浦语·灵笔) is a multi-modality conversational language model that is developed\
 by Shanghai AI Laboratory (上海人工智能实验室). It is designed to be helpful, honest, and harmless.
- InternLM-XComposer (浦语·灵笔) can understand and communicate fluently in the language chosen by\
 the user such as English and 中文.
- InternLM-XComposer (浦语·灵笔) is capable of comprehending and articulating responses\
 effectively based on the provided image."""


@register_model("xcomposer2_4khd")
class XComposer2_4KHD(lmms):
    def __init__(
        self,
        pretrained: str = "internlm/internlm-xcomposer2-4khd-7b",
        device: Optional[str] = "cuda:0",
        batch_size: Optional[Union[int, str]] = 1,
        device_map="cuda:0",
        need_bos: bool = True,
        padding: bool = False,
        half: bool = False,
        **kwargs,
    ) -> None:
        super().__init__()

        accelerator_kwargs = InitProcessGroupKwargs(timeout=timedelta(weeks=52))
        accelerator = Accelerator(kwargs_handlers=[accelerator_kwargs])
        if accelerator.num_processes > 1:
            self._device = torch.device(f"cuda:{accelerator.local_process_index}")
            self.device_map = f"cuda:{accelerator.local_process_index}"
        elif accelerator.num_processes == 1 and device_map == "auto":
            self._device = torch.device(device)
            self.device_map = device_map
        else:
            self._device = torch.device(f"cuda:{accelerator.local_process_index}")
            self.device_map = f"cuda:{accelerator.local_process_index}"

        self.pretrained = pretrained
        self.need_bos = need_bos
        self.padding = padding
        self._model = AutoModel.from_pretrained(self.pretrained, device_map=self.device_map, trust_remote_code=True)
        self._tokenizer = AutoTokenizer.from_pretrained(self.pretrained, trust_remote_code=True)
        self.model.tokenizer = self.tokenizer
        self.batch_size_per_gpu = batch_size

        if accelerator.num_processes > 1:
            assert accelerator.distributed_type in [DistributedType.FSDP, DistributedType.MULTI_GPU, DistributedType.DEEPSPEED], "Unsupported distributed type provided. Only DDP and FSDP are supported."
            # If you want to use DistributedType.DEEPSPEED, you have to run accelerate config before using the model
            # Also, you have to select zero stage 0 (equivalent to DDP) in order to make the prepare model works
            # I tried to set different parameters in the kwargs to let default zero 2 stage works, but it didn't work.
            if accelerator.distributed_type == DistributedType.DEEPSPEED:
                kwargs = {
                    "train_micro_batch_size_per_gpu": self.batch_size_per_gpu,
                    "train_batch_size": self.batch_size_per_gpu * accelerator.num_processes,
                }
                AcceleratorState().deepspeed_plugin.deepspeed_config_process(must_match=True, **kwargs)
                eval_logger.info("Detected that you are using DistributedType.DEEPSPEED. Make sure you run `accelerate config` and set zero stage to 0")
            if accelerator.distributed_type == DistributedType.FSDP or accelerator.distributed_type == DistributedType.DEEPSPEED:
                self._model = accelerator.prepare(self.model)
            else:
                self._model = accelerator.prepare_model(self.model, evaluation_mode=True)
            self.accelerator = accelerator
            if self.accelerator.is_local_main_process:
                eval_logger.info(f"Using {accelerator.num_processes} devices with data parallelism")
            self._rank = self.accelerator.local_process_index
            self._world_size = self.accelerator.num_processes
        elif accelerator.num_processes == 1 and device_map == "auto":
            eval_logger.info(f"Using {accelerator.num_processes} devices with tensor parallelism")
            self._rank = 0
            self._word_size = 1
        else:
            eval_logger.info(f"Using single device: {self._device}")
            self.model.to(self._device)
            self._rank = 0
            self._world_size = 1

    @property
    def config(self):
        # return the associated transformers.AutoConfig for the given pretrained model.
        return self._config

    @property
    def tokenizer(self):
        return self._tokenizer

    @property
    def model(self):
        # returns the model, unwrapping it if using Accelerate
        if hasattr(self, "accelerator"):
            return self.accelerator.unwrap_model(self._model)
        else:
            return self._model

    @property
    def batch_size(self):
        return self.batch_size_per_gpu

    @property
    def device(self):
        return self._device

    @property
    def rank(self):
        return self._rank

    @property
    def world_size(self):
        return self._world_size

    def flatten(self, input):
        new_list = []
        for i in input:
            for j in i:
                new_list.append(j)
        return new_list

    def generate_until(self, requests) -> List[str]:
        res = []
        pbar = tqdm(total=len(requests), disable=(self.rank != 0), desc="Model Responding")

        for contexts, gen_kwargs, doc_to_visual, doc_id, task, split in [reg.args for reg in requests]:
            # encode, pad, and truncate contexts for this batch
            if "[UNUSED_TOKEN_146]" not in contexts:
                contexts = f"[UNUSED_TOKEN_146]user\n{contexts}[UNUSED_TOKEN_145]\n[UNUSED_TOKEN_146]assistant\n"
            visuals = [doc_to_visual(self.task_dict[task][split][doc_id])]
            visuals = self.flatten(visuals)

            if "hd_num" not in gen_kwargs:
                if listinstr(["docvqa_test", "infovqa_test"], task.lower()):
                    self.model.hd_num = 65
                elif listinstr(["docvqa_val", "infovqa_val", "OCRBench"], task.lower()):
                    self.model.hd_num = 55
                elif listinstr(["mmmu", "mmbench", "mmvet"], task.lower()):
                    self.model.hd_num = 16
                else:
                    self.model.hd_num = 25
            else:
                self.model.hd_num = gen_kwargs.pop("hd_num")

            pt1 = 0
            embeds = []
            im_mask = []
            images_loc = [0]
            need_bos = self.need_bos
            padding = self.padding
            for i, pts in enumerate(images_loc + [len(contexts)]):
                subtext = contexts[pt1:pts]
                if need_bos or len(subtext) > 0:
                    text_embeds = self.model.encode_text(subtext, add_special_tokens=need_bos).to(self.device)
                    embeds.append(text_embeds)
                    im_mask.append(torch.zeros(text_embeds.shape[:2]).to(self.device))
                    need_bos = False
                if i < len(visuals):
                    image = visuals[i]

                    image = HD_transform(image, im_num=self.model.hd_num)
                    image = self.model.vis_processor(image).unsqueeze(0).to(self.device)
                    image_embeds = self.model.encode_img(image)
                    embeds.append(image_embeds)
                    im_mask.append(torch.ones(image_embeds.shape[:2]).to(self.device))
                pt1 = pts
            embeds = torch.cat(embeds, dim=1)
            im_mask = torch.cat(im_mask, dim=1)
            im_mask = im_mask.bool()

            if "max_new_tokens" not in gen_kwargs:
                gen_kwargs["max_new_tokens"] = 1024
            if "temperature" not in gen_kwargs:
                gen_kwargs["temperature"] = 0
            if "top_p" not in gen_kwargs:
                gen_kwargs["top_p"] = None
            if "num_beams" not in gen_kwargs:
                gen_kwargs["num_beams"] = 1
            if "do_sample" not in gen_kwargs:
                gen_kwargs["do_sample"] = False
            if "repetition_penalty" not in gen_kwargs:
                gen_kwargs["repetition_penalty"] = 1.0

            outputs = self.model.generate(
                inputs_embeds=embeds,
                im_mask=im_mask,
                temperature=gen_kwargs["temperature"],
                max_new_tokens=gen_kwargs["max_new_tokens"],
                num_beams=gen_kwargs["num_beams"],
                do_sample=gen_kwargs["do_sample"],
                repetition_penalty=gen_kwargs["repetition_penalty"],
            )
            output_token = outputs[0]
            if output_token[0] == 0 or output_token[0] == 1:
                output_token = output_token[1:]
            output_text = self.model.tokenizer.decode(output_token, add_special_tokens=False)
            output_text = output_text.split("[UNUSED_TOKEN_145]")[0].strip()
            output_text = output_text.split("<|im_end|>")[0].strip()
            # if DATASET_TYPE(task) == "multi-choice":
            #     output_text = pattern.findall(output_text)
            #     if len(output_text) == 0:
            #         print("Error:", output_text)
            #         output_text = "Z"
            #     if type(output_text) == list:
            #         output_text = output_text[0]
            res.append(output_text)
            pbar.update(1)
        pbar.close()
        return res

    def loglikelihood(self, requests: List[Instance]) -> List[Tuple[float, bool]]:
        return super().loglikelihood(requests)

    def generate_until_multi_round(self, requests) -> List[str]:
        raise NotImplementedError("TODO: Implement multi-round generation")


def padding_336(b):
    width, height = b.size
    tar = int(np.ceil(height / 336) * 336)
    top_padding = int((tar - height) / 2)
    bottom_padding = tar - height - top_padding
    left_padding = 0
    right_padding = 0
    b = transforms.functional.pad(b, [left_padding, top_padding, right_padding, bottom_padding], fill=[255, 255, 255])

    return b


def HD_transform(img, im_num=16):
    width, height = img.size
    trans = False
    if width < height:
        img = img.transpose(Image.TRANSPOSE)
        trans = True
        width, height = img.size
    ratio = width / height
    scale = 1
    while scale * np.ceil(scale / ratio) <= im_num:
        scale += 1
    scale -= 1
    new_w = int(scale * 336)
    new_h = int(new_w / ratio)

    img = transforms.functional.resize(
        img,
        [new_h, new_w],
    )
    img = padding_336(img)
    width, height = img.size
    assert width * height <= im_num * 336 * 336
    if trans:
        img = img.transpose(Image.TRANSPOSE)

    return img


def listinstr(lst, s):
    assert isinstance(lst, list)
    for item in lst:
        if item in s:
            return True
    return False


def DATASET_TYPE(dataset):
    # Dealing with Custom Dataset
    dataset = dataset.lower()
    if listinstr(["mmbench", "seedbench", "ccbench", "mmmu", "scienceqa", "ai2d", "mmstar"], dataset):
        return "multi-choice"
    elif listinstr(["mme", "hallusion"], dataset):
        return "Y/N"
    elif "coco" in dataset:
        return "Caption"
    elif listinstr(["ocrvqa", "textvqa", "chartqa", "mathvista", "docvqa", "infovqa", "llavabench", "mmvet", "ocrbench"], dataset):
        return "VQA"
    else:
        return "QA"
