import argparse
import logging
import os
import os.path as osp
import random
import time
from collections import OrderedDict

import numpy
import numpy as np
import torch
from PIL import Image
from torchvision.transforms import ToTensor
from tqdm import tqdm

import dlas.utils
import dlas.utils.options as option
import dlas.utils.util as util
from dlas.data import create_dataloader, create_dataset
from dlas.trainer.ExtensibleTrainer import ExtensibleTrainer

# A rough copy of test.py that repeatedly performs SR, then downsamples the result and does it again.


def forward_pass(model, data, output_dir, it):
    with torch.no_grad():
        model.feed_data(data, 0)
        model.test()

    visuals = model.get_current_visuals()['rlt'].cpu()
    img_path = data['GT_path'][0]
    img_name = osp.splitext(osp.basename(img_path))[0]
    sr_img = util.tensor2img(visuals[0])  # uint8

    # save images
    suffixes = [f'_it_{it}']
    for suffix in suffixes:
        save_img_path = osp.join(output_dir, img_name + suffix + '.png')
        util.save_img(sr_img, save_img_path)
    return visuals


if __name__ == "__main__":
    # Set seeds
    torch.manual_seed(5555)
    random.seed(5555)
    np.random.seed(5555)

    # options
    torch.backends.cudnn.benchmark = True
    want_metrics = False
    parser = argparse.ArgumentParser()
    parser.add_argument('-opt', type=str, help='Path to options YAML file.',
                        default='../options/test_diffusion_unet.yml')
    opt = option.parse(parser.parse_args().opt, is_train=False)
    opt = option.dict_to_nonedict(opt)
    utils.util.loaded_options = opt

    util.mkdirs(
        (path for key, path in opt['path'].items()
         if not key == 'experiments_root' and 'pretrain_model' not in key and 'resume' not in key))
    util.setup_logger('base', opt['path']['log'], 'test_' + opt['name'], level=logging.INFO,
                      screen=True, tofile=True)
    logger = logging.getLogger('base')
    logger.info(option.dict2str(opt))

    # Load test image
    im = ToTensor()(Image.open(opt['image'])) * 2 - 1
    _, h, w = im.shape
    if h % 2 == 1:
        im = im[:, 1:, :]
        h = h-1
    if w % 2 == 1:
        im = im[:, :, 1:]
        w = w-1
    dh, dw = (h - 32 * (h // 32)) // 2, (w - 32 * (w // 32)) // 2
    if dh > 0:
        im = im[:, dh:-dh]
    if dw > 0:
        im = im[:, :, dw:-dw]
    im = im[:3].unsqueeze(0)

    model = ExtensibleTrainer(opt)
    results_dir = osp.join(opt['path']['results_root'],
                           os.path.basename(opt['image']))
    util.mkdir(results_dir)
    for i in range(100):
        data = {
            'hq': im.to('cuda'),
            'lq': im.to('cuda'),
            'corruption_entropy': torch.tensor([[.3, .3]], device='cuda',
                                               dtype=torch.float),
            'GT_path': opt['image']
        }
        im = torch.nn.functional.interpolate(forward_pass(
            model, data, results_dir, i), scale_factor=.5, mode="area")
        im = im * 2 - 1