import numpy as np
import cv2
import os
import math
import requests
from torch.hub import download_url_to_file, get_dir
from tqdm import tqdm
from urllib.parse import urlparse
import torch
import random
from PIL import Image


annotator_ckpts_path = os.path.join(os.path.dirname(__file__), "ckpts")

def tensor2pil(image):
    return Image.fromarray(np.clip(255. * image.cpu().numpy().squeeze(), 0, 255).astype(np.uint8))

# PIL to Tensor
def pil2tensor(image):
    return torch.from_numpy(np.array(image).astype(np.float32) / 255.0)

def HWC3(x):
    assert x.dtype == np.uint8
    if x.ndim == 2:
        x = x[:, :, None]
    assert x.ndim == 3
    H, W, C = x.shape
    assert C == 1 or C == 3 or C == 4
    if C == 3:
        return x
    if C == 1:
        return np.concatenate([x, x, x], axis=2)
    if C == 4:
        color = x[:, :, 0:3].astype(np.float32)
        alpha = x[:, :, 3:4].astype(np.float32) / 255.0
        y = color * alpha + 255.0 * (1.0 - alpha)
        y = y.clip(0, 255).astype(np.uint8)
        return y


def resize_image(input_image, resolution=None):
    H, W, C = input_image.shape
    H = float(H)
    W = float(W)
    k = 0
    if resolution is not None:
        k = float(resolution) / min(H, W)
        H *= k
        W *= k
    H = int(np.round(H / 64.0)) * 64
    W = int(np.round(W / 64.0)) * 64
    img = cv2.resize(input_image, (W, H), interpolation=cv2.INTER_LANCZOS4 if k > 1 else cv2.INTER_AREA)
    return img


#####COPIED FROM BASICSR####
def sizeof_fmt(size, suffix='B'):
    """Get human readable file size.

    Args:
        size (int): File size.
        suffix (str): Suffix. Default: 'B'.

    Return:
        str: Formatted file size.
    """
    for unit in ['', 'K', 'M', 'G', 'T', 'P', 'E', 'Z']:
        if abs(size) < 1024.0:
            return f'{size:3.1f} {unit}{suffix}'
        size /= 1024.0
    return f'{size:3.1f} Y{suffix}'


def download_file_from_google_drive(file_id, save_path):
    """Download files from google drive.

    Ref:
    https://stackoverflow.com/questions/25010369/wget-curl-large-file-from-google-drive  # noqa E501

    Args:
        file_id (str): File id.
        save_path (str): Save path.
    """

    session = requests.Session()
    URL = 'https://docs.google.com/uc?export=download'
    params = {'id': file_id}

    response = session.get(URL, params=params, stream=True)
    token = get_confirm_token(response)
    if token:
        params['confirm'] = token
        response = session.get(URL, params=params, stream=True)

    # get file size
    response_file_size = session.get(URL, params=params, stream=True, headers={'Range': 'bytes=0-2'})
    if 'Content-Range' in response_file_size.headers:
        file_size = int(response_file_size.headers['Content-Range'].split('/')[1])
    else:
        file_size = None

    save_response_content(response, save_path, file_size)


def get_confirm_token(response):
    for key, value in response.cookies.items():
        if key.startswith('download_warning'):
            return value
    return None


def save_response_content(response, destination, file_size=None, chunk_size=32768):
    if file_size is not None:
        pbar = tqdm(total=math.ceil(file_size / chunk_size), unit='chunk')

        readable_file_size = sizeof_fmt(file_size)
    else:
        pbar = None

    with open(destination, 'wb') as f:
        downloaded_size = 0
        for chunk in response.iter_content(chunk_size):
            downloaded_size += chunk_size
            if pbar is not None:
                pbar.update(1)
                pbar.set_description(f'Download {sizeof_fmt(downloaded_size)} / {readable_file_size}')
            if chunk:  # filter out keep-alive new chunks
                f.write(chunk)
        if pbar is not None:
            pbar.close()


def load_file_from_url(url, model_dir=None, progress=True, file_name=None):
    """Load file form http url, will download models if necessary.

    Ref:https://github.com/1adrianb/face-alignment/blob/master/face_alignment/utils.py

    Args:
        url (str): URL to be downloaded.
        model_dir (str): The path to save the downloaded model. Should be a full path. If None, use pytorch hub_dir.
            Default: None.
        progress (bool): Whether to show the download progress. Default: True.
        file_name (str): The downloaded file name. If None, use the file name in the url. Default: None.

    Returns:
        str: The path to the downloaded file.
    """
    if model_dir is None:  # use the pytorch hub_dir
        hub_dir = get_dir()
        model_dir = os.path.join(hub_dir, 'checkpoints')

    os.makedirs(model_dir, exist_ok=True)

    parts = urlparse(url)
    filename = os.path.basename(parts.path)
    if file_name is not None:
        filename = file_name
    cached_file = os.path.abspath(os.path.join(model_dir, filename))
    if not os.path.exists(cached_file):
        print(f'Downloading: "{url}" to {cached_file}\n')
        download_url_to_file(url, cached_file, hash_prefix=None, progress=progress)
    return cached_file


def load_state_dict(modelpath):
    wrapper = torch.load(modelpath)
    return wrapper["state_dict"] if "state_dict" in wrapper else wrapper

def nms(x, t, s):
    x = cv2.GaussianBlur(x.astype(np.float32), (0, 0), s)

    f1 = np.array([[0, 0, 0], [1, 1, 1], [0, 0, 0]], dtype=np.uint8)
    f2 = np.array([[0, 1, 0], [0, 1, 0], [0, 1, 0]], dtype=np.uint8)
    f3 = np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]], dtype=np.uint8)
    f4 = np.array([[0, 0, 1], [0, 1, 0], [1, 0, 0]], dtype=np.uint8)

    y = np.zeros_like(x)

    for f in [f1, f2, f3, f4]:
        np.putmask(y, cv2.dilate(x, kernel=f) == x, x)

    z = np.zeros_like(y, dtype=np.uint8)
    z[y > t] = 255
    return z


def make_noise_disk(H, W, C, F):
    noise = np.random.uniform(low=0, high=1, size=((H // F) + 2, (W // F) + 2, C))
    noise = cv2.resize(noise, (W + 2 * F, H + 2 * F), interpolation=cv2.INTER_CUBIC)
    noise = noise[F: F + H, F: F + W]
    noise -= np.min(noise)
    noise /= np.max(noise)
    if C == 1:
        noise = noise[:, :, None]
    return noise


def min_max_norm(x):
    x -= np.min(x)
    x /= np.maximum(np.max(x), 1e-5)
    return x


def safe_step(x, step=2):
    y = x.astype(np.float32) * float(step + 1)
    y = y.astype(np.int32).astype(np.float32) / float(step)
    return y


def img2mask(img, H, W, low=10, high=90):
    assert img.ndim == 3 or img.ndim == 2
    assert img.dtype == np.uint8

    if img.ndim == 3:
        y = img[:, :, random.randrange(0, img.shape[2])]
    else:
        y = img

    y = cv2.resize(y, (W, H), interpolation=cv2.INTER_CUBIC)

    if random.uniform(0, 1) < 0.5:
        y = 255 - y

    return y < np.percentile(y, random.randrange(low, high))