import os
import math
import torch
import logging
import random
import subprocess
import numpy as np
import torch.distributed as dist

# from torch._six import inf
from torch import inf
from PIL import Image
from typing import Union, Iterable
from collections import OrderedDict
from torch.utils.tensorboard import SummaryWriter   

from diffusers.utils import is_bs4_available, is_ftfy_available

import html
import re
import urllib.parse as ul

if is_bs4_available():
    from bs4 import BeautifulSoup

if is_ftfy_available():
    import ftfy

_tensor_or_tensors = Union[torch.Tensor, Iterable[torch.Tensor]]


#################################################################################
#                             Training Clip Gradients                           #
#################################################################################

def get_grad_norm(
        parameters: _tensor_or_tensors, norm_type: float = 2.0) -> torch.Tensor:
    r"""
    Copy from torch.nn.utils.clip_grad_norm_

    Clips gradient norm of an iterable of parameters.

    The norm is computed over all gradients together, as if they were
    concatenated into a single vector. Gradients are modified in-place.

    Args:
        parameters (Iterable[Tensor] or Tensor): an iterable of Tensors or a
            single Tensor that will have gradients normalized
        max_norm (float or int): max norm of the gradients
        norm_type (float or int): type of the used p-norm. Can be ``'inf'`` for
            infinity norm.
        error_if_nonfinite (bool): if True, an error is thrown if the total
            norm of the gradients from :attr:`parameters` is ``nan``,
            ``inf``, or ``-inf``. Default: False (will switch to True in the future)

    Returns:
        Total norm of the parameter gradients (viewed as a single vector).
    """
    if isinstance(parameters, torch.Tensor):
        parameters = [parameters]
    grads = [p.grad for p in parameters if p.grad is not None]
    norm_type = float(norm_type)
    if len(grads) == 0:
        return torch.tensor(0.)
    device = grads[0].device
    if norm_type == inf:
        norms = [g.detach().abs().max().to(device) for g in grads]
        total_norm = norms[0] if len(norms) == 1 else torch.max(torch.stack(norms))
    else:
        total_norm = torch.norm(torch.stack([torch.norm(g.detach(), norm_type).to(device) for g in grads]), norm_type)
    return total_norm

def clip_grad_norm_(
        parameters: _tensor_or_tensors, max_norm: float, norm_type: float = 2.0,
        error_if_nonfinite: bool = False, clip_grad = True) -> torch.Tensor:
    r"""
    Copy from torch.nn.utils.clip_grad_norm_

    Clips gradient norm of an iterable of parameters.

    The norm is computed over all gradients together, as if they were
    concatenated into a single vector. Gradients are modified in-place.

    Args:
        parameters (Iterable[Tensor] or Tensor): an iterable of Tensors or a
            single Tensor that will have gradients normalized
        max_norm (float or int): max norm of the gradients
        norm_type (float or int): type of the used p-norm. Can be ``'inf'`` for
            infinity norm.
        error_if_nonfinite (bool): if True, an error is thrown if the total
            norm of the gradients from :attr:`parameters` is ``nan``,
            ``inf``, or ``-inf``. Default: False (will switch to True in the future)

    Returns:
        Total norm of the parameter gradients (viewed as a single vector).
    """
    if isinstance(parameters, torch.Tensor):
        parameters = [parameters]
    grads = [p.grad for p in parameters if p.grad is not None]
    max_norm = float(max_norm)
    norm_type = float(norm_type)
    if len(grads) == 0:
        return torch.tensor(0.)
    device = grads[0].device
    if norm_type == inf:
        norms = [g.detach().abs().max().to(device) for g in grads]
        total_norm = norms[0] if len(norms) == 1 else torch.max(torch.stack(norms))
    else:
        total_norm = torch.norm(torch.stack([torch.norm(g.detach(), norm_type).to(device) for g in grads]), norm_type)
    # print(total_norm)

    if clip_grad:
        if error_if_nonfinite and torch.logical_or(total_norm.isnan(), total_norm.isinf()):
            raise RuntimeError(
                f'The total norm of order {norm_type} for gradients from '
                '`parameters` is non-finite, so it cannot be clipped. To disable '
                'this error and scale the gradients by the non-finite norm anyway, '
                'set `error_if_nonfinite=False`')
        clip_coef = max_norm / (total_norm + 1e-6)
        # Note: multiplying by the clamped coef is redundant when the coef is clamped to 1, but doing so
        # avoids a `if clip_coef < 1:` conditional which can require a CPU <=> device synchronization
        # when the gradients do not reside in CPU memory.
        clip_coef_clamped = torch.clamp(clip_coef, max=1.0)
        for g in grads:
            g.detach().mul_(clip_coef_clamped.to(g.device))
        # gradient_cliped = torch.norm(torch.stack([torch.norm(g.detach(), norm_type).to(device) for g in grads]), norm_type)
        # print(gradient_cliped)
    return total_norm

def get_experiment_dir(root_dir, args):
    # if args.pretrained is not None and 'Latte-XL-2-256x256.pt' not in args.pretrained:
    #     root_dir += '-WOPRE'
    if args.use_compile:
        root_dir += '-Compile' # speedup by torch compile
    if args.fixed_spatial:
        root_dir += '-FixedSpa'
    if args.enable_xformers_memory_efficient_attention:
        root_dir += '-Xfor'
    if args.gradient_checkpointing:
        root_dir += '-Gc'
    if args.mixed_precision:
        root_dir += '-Amp'
    if args.image_size == 512:
        root_dir += '-512'
    return root_dir

#################################################################################
#                             Training Logger                                   #
#################################################################################

def create_logger(logging_dir):
    """
    Create a logger that writes to a log file and stdout.
    """
    if dist.get_rank() == 0:  # real logger
        logging.basicConfig(
            level=logging.INFO,
            # format='[\033[34m%(asctime)s\033[0m] %(message)s',
            format='[%(asctime)s] %(message)s',
            datefmt='%Y-%m-%d %H:%M:%S',
            handlers=[logging.StreamHandler(), logging.FileHandler(f"{logging_dir}/log.txt")]
        )
        logger = logging.getLogger(__name__)
        
    else:  # dummy logger (does nothing)
        logger = logging.getLogger(__name__)
        logger.addHandler(logging.NullHandler())
    return logger


def create_tensorboard(tensorboard_dir):
    """
    Create a tensorboard that saves losses.
    """
    if dist.get_rank() == 0:  # real tensorboard 
        # tensorboard 
        writer = SummaryWriter(tensorboard_dir)

    return writer

def write_tensorboard(writer, *args):
    '''
    write the loss information to a tensorboard file.
    Only for pytorch DDP mode.
    '''
    if dist.get_rank() == 0:  # real tensorboard
        writer.add_scalar(args[0], args[1], args[2])

#################################################################################
#                      EMA Update/ DDP Training Utils                           #
#################################################################################

@torch.no_grad()
def update_ema(ema_model, model, decay=0.9999):
    """
    Step the EMA model towards the current model.
    """
    ema_params = OrderedDict(ema_model.named_parameters())
    model_params = OrderedDict(model.named_parameters())

    for name, param in model_params.items():
        # TODO: Consider applying only to params that require_grad to avoid small numerical changes of pos_embed
        ema_params[name].mul_(decay).add_(param.data, alpha=1 - decay)

def requires_grad(model, flag=True):
    """
    Set requires_grad flag for all parameters in a model.
    """
    for p in model.parameters():
        p.requires_grad = flag

def cleanup():
    """
    End DDP training.
    """
    dist.destroy_process_group()
    

def setup_distributed(backend="nccl", port=None):
    """Initialize distributed training environment.
    support both slurm and torch.distributed.launch
    see torch.distributed.init_process_group() for more details
    """
    num_gpus = torch.cuda.device_count()

    if "SLURM_JOB_ID" in os.environ:
        rank = int(os.environ["SLURM_PROCID"])
        world_size = int(os.environ["SLURM_NTASKS"])
        node_list = os.environ["SLURM_NODELIST"]
        addr = subprocess.getoutput(f"scontrol show hostname {node_list} | head -n1")
        # specify master port
        if port is not None:
            os.environ["MASTER_PORT"] = str(port)
        elif "MASTER_PORT" not in os.environ:
            # os.environ["MASTER_PORT"] = "29566"
            os.environ["MASTER_PORT"] = str(29567 + num_gpus)
        if "MASTER_ADDR" not in os.environ:
            os.environ["MASTER_ADDR"] = addr
        os.environ["WORLD_SIZE"] = str(world_size)
        os.environ["LOCAL_RANK"] = str(rank % num_gpus)
        os.environ["RANK"] = str(rank)
    else:
        rank = int(os.environ["RANK"])
        world_size = int(os.environ["WORLD_SIZE"])

    # torch.cuda.set_device(rank % num_gpus)

    dist.init_process_group(
        backend=backend,
        world_size=world_size,
        rank=rank,
    )

#################################################################################
#                             Testing  Utils                                    #
#################################################################################

def save_video_grid(video, nrow=None):
    b, t, h, w, c = video.shape
    
    if nrow is None:
        nrow = math.ceil(math.sqrt(b))
    ncol = math.ceil(b / nrow)
    padding = 1
    video_grid = torch.zeros((t, (padding + h) * nrow + padding,
                           (padding + w) * ncol + padding, c), dtype=torch.uint8)
    
    print(video_grid.shape)
    for i in range(b):
        r = i // ncol
        c = i % ncol
        start_r = (padding + h) * r
        start_c = (padding + w) * c
        video_grid[:, start_r:start_r + h, start_c:start_c + w] = video[i]
    
    return video_grid


#################################################################################
#                             MMCV  Utils                                    #
#################################################################################


def collect_env():
    # Copyright (c) OpenMMLab. All rights reserved.
    from mmcv.utils import collect_env as collect_base_env
    from mmcv.utils import get_git_hash
    """Collect the information of the running environments."""
    
    env_info = collect_base_env()
    env_info['MMClassification'] = get_git_hash()[:7]

    for name, val in env_info.items():
        print(f'{name}: {val}')
    
    print(torch.cuda.get_arch_list())
    print(torch.version.cuda)


#################################################################################
#                          Pixart-alpha  Utils                                  #
#################################################################################

bad_punct_regex = re.compile(
        r"[" + "#®•©™&@·º½¾¿¡§~" + "\)" + "\(" + "\]" + "\[" + "\}" + "\{" + "\|" + "\\" + "\/" + "\*" + r"]{1,}"
)  

def text_preprocessing(text, clean_caption=False):
    if clean_caption and not is_bs4_available():
        clean_caption = False

    if clean_caption and not is_ftfy_available():
        clean_caption = False

    if not isinstance(text, (tuple, list)):
        text = [text]

    def process(text: str):
        if clean_caption:
            text = clean_caption(text)
            text = clean_caption(text)
        else:
            text = text.lower().strip()
        return text

    return [process(t) for t in text]

# Copied from diffusers.pipelines.deepfloyd_if.pipeline_if.IFPipeline._clean_caption
def clean_caption(caption):
    caption = str(caption)
    caption = ul.unquote_plus(caption)
    caption = caption.strip().lower()
    caption = re.sub("<person>", "person", caption)
    # urls:
    caption = re.sub(
        r"\b((?:https?:(?:\/{1,3}|[a-zA-Z0-9%])|[a-zA-Z0-9.\-]+[.](?:com|co|ru|net|org|edu|gov|it)[\w/-]*\b\/?(?!@)))",  # noqa
        "",
        caption,
    )  # regex for urls
    caption = re.sub(
        r"\b((?:www:(?:\/{1,3}|[a-zA-Z0-9%])|[a-zA-Z0-9.\-]+[.](?:com|co|ru|net|org|edu|gov|it)[\w/-]*\b\/?(?!@)))",  # noqa
        "",
        caption,
    )  # regex for urls
    # html:
    caption = BeautifulSoup(caption, features="html.parser").text

    # @<nickname>
    caption = re.sub(r"@[\w\d]+\b", "", caption)

    # 31C0—31EF CJK Strokes
    # 31F0—31FF Katakana Phonetic Extensions
    # 3200—32FF Enclosed CJK Letters and Months
    # 3300—33FF CJK Compatibility
    # 3400—4DBF CJK Unified Ideographs Extension A
    # 4DC0—4DFF Yijing Hexagram Symbols
    # 4E00—9FFF CJK Unified Ideographs
    caption = re.sub(r"[\u31c0-\u31ef]+", "", caption)
    caption = re.sub(r"[\u31f0-\u31ff]+", "", caption)
    caption = re.sub(r"[\u3200-\u32ff]+", "", caption)
    caption = re.sub(r"[\u3300-\u33ff]+", "", caption)
    caption = re.sub(r"[\u3400-\u4dbf]+", "", caption)
    caption = re.sub(r"[\u4dc0-\u4dff]+", "", caption)
    caption = re.sub(r"[\u4e00-\u9fff]+", "", caption)
    #######################################################

    # все виды тире / all types of dash --> "-"
    caption = re.sub(
        r"[\u002D\u058A\u05BE\u1400\u1806\u2010-\u2015\u2E17\u2E1A\u2E3A\u2E3B\u2E40\u301C\u3030\u30A0\uFE31\uFE32\uFE58\uFE63\uFF0D]+",  # noqa
        "-",
        caption,
    )

    # кавычки к одному стандарту
    caption = re.sub(r"[`´«»“”¨]", '"', caption)
    caption = re.sub(r"[‘’]", "'", caption)

    # &quot;
    caption = re.sub(r"&quot;?", "", caption)
    # &amp
    caption = re.sub(r"&amp", "", caption)

    # ip adresses:
    caption = re.sub(r"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}", " ", caption)

    # article ids:
    caption = re.sub(r"\d:\d\d\s+$", "", caption)

    # \n
    caption = re.sub(r"\\n", " ", caption)

    # "#123"
    caption = re.sub(r"#\d{1,3}\b", "", caption)
    # "#12345.."
    caption = re.sub(r"#\d{5,}\b", "", caption)
    # "123456.."
    caption = re.sub(r"\b\d{6,}\b", "", caption)
    # filenames:
    caption = re.sub(r"[\S]+\.(?:png|jpg|jpeg|bmp|webp|eps|pdf|apk|mp4)", "", caption)

    #
    caption = re.sub(r"[\"\']{2,}", r'"', caption)  # """AUSVERKAUFT"""
    caption = re.sub(r"[\.]{2,}", r" ", caption)  # """AUSVERKAUFT"""

    caption = re.sub(bad_punct_regex, r" ", caption)  # ***AUSVERKAUFT***, #AUSVERKAUFT
    caption = re.sub(r"\s+\.\s+", r" ", caption)  # " . "

    # this-is-my-cute-cat / this_is_my_cute_cat
    regex2 = re.compile(r"(?:\-|\_)")
    if len(re.findall(regex2, caption)) > 3:
        caption = re.sub(regex2, " ", caption)

    caption = ftfy.fix_text(caption)
    caption = html.unescape(html.unescape(caption))

    caption = re.sub(r"\b[a-zA-Z]{1,3}\d{3,15}\b", "", caption)  # jc6640
    caption = re.sub(r"\b[a-zA-Z]+\d+[a-zA-Z]+\b", "", caption)  # jc6640vc
    caption = re.sub(r"\b\d+[a-zA-Z]+\d+\b", "", caption)  # 6640vc231

    caption = re.sub(r"(worldwide\s+)?(free\s+)?shipping", "", caption)
    caption = re.sub(r"(free\s)?download(\sfree)?", "", caption)
    caption = re.sub(r"\bclick\b\s(?:for|on)\s\w+", "", caption)
    caption = re.sub(r"\b(?:png|jpg|jpeg|bmp|webp|eps|pdf|apk|mp4)(\simage[s]?)?", "", caption)
    caption = re.sub(r"\bpage\s+\d+\b", "", caption)

    caption = re.sub(r"\b\d*[a-zA-Z]+\d+[a-zA-Z]+\d+[a-zA-Z\d]*\b", r" ", caption)  # j2d1a2a...

    caption = re.sub(r"\b\d+\.?\d*[xх×]\d+\.?\d*\b", "", caption)

    caption = re.sub(r"\b\s+\:\s+", r": ", caption)
    caption = re.sub(r"(\D[,\./])\b", r"\1 ", caption)
    caption = re.sub(r"\s+", " ", caption)

    caption.strip()

    caption = re.sub(r"^[\"\']([\w\W]+)[\"\']$", r"\1", caption)
    caption = re.sub(r"^[\'\_,\-\:;]", r"", caption)
    caption = re.sub(r"[\'\_,\-\:\-\+]$", r"", caption)
    caption = re.sub(r"^\.\S+$", "", caption)

    return caption.strip()