"""
Train a diffusion model on images.
"""
import json
import sys
import os

sys.path.append('.')

# from dnnlib import EasyDict
import traceback

import torch as th
import torch.multiprocessing as mp
import torch.distributed as dist
import numpy as np

import argparse
import dnnlib
from guided_diffusion import dist_util, logger
from guided_diffusion.resample import create_named_schedule_sampler
from guided_diffusion.script_util import (
    args_to_dict,
    add_dict_to_argparser,
    continuous_diffusion_defaults,
    model_and_diffusion_defaults,
    create_model_and_diffusion,
)
from guided_diffusion.continuous_diffusion import make_diffusion as make_sde_diffusion
import nsr
import nsr.lsgm
# from nsr.train_util_diffusion import TrainLoop3DDiffusion as TrainLoop

from nsr.script_util import create_3DAE_model, encoder_and_nsr_defaults, loss_defaults, rendering_options_defaults, eg3d_options_default
from datasets.shapenet import load_data, load_eval_data, load_memory_data
from nsr.losses.builder import E3DGELossClass

from torch_utils import legacy, misc
from torch.utils.data import Subset
from pdb import set_trace as st

from dnnlib.util import EasyDict, InfiniteSampler
# from .vit_triplane_train_FFHQ import init_dataset_kwargs
from datasets.eg3d_dataset import init_dataset_kwargs

# from torch.utils.tensorboard import SummaryWriter

SEED = 0


def training_loop(args):
    # def training_loop(args):
    logger.log("dist setup...")

    th.cuda.set_device(
        args.local_rank)  # set this line to avoid extra memory on rank 0
    th.cuda.empty_cache()

    th.cuda.manual_seed_all(SEED)
    np.random.seed(SEED)

    dist_util.setup_dist(args)

    # st() # mark

    # logger.configure(dir=args.logdir, format_strs=["tensorboard", "csv"])
    logger.configure(dir=args.logdir)

    logger.log("creating ViT encoder and NSR decoder...")
    # st() # mark
    device = dist_util.dev()

    args.img_size = [args.image_size_encoder]

    logger.log("creating model and diffusion...")
    # * set denoise model args

    if args.denoise_in_channels == -1:
        args.diffusion_input_size = args.image_size_encoder
        args.denoise_in_channels = args.out_chans
        args.denoise_out_channels = args.out_chans
    else:
        assert args.denoise_out_channels != -1

    # args.image_size = args.image_size_encoder  # 224, follow the triplane size

    # if args.diffusion_input_size == -1:
    # else:
    # args.image_size = args.diffusion_input_size

    denoise_model, diffusion = create_model_and_diffusion(
        **args_to_dict(args,
                       model_and_diffusion_defaults().keys()))
    denoise_model.to(dist_util.dev())
    denoise_model.train()

    opts = eg3d_options_default()
    if args.sr_training:
        args.sr_kwargs = dnnlib.EasyDict(
            channel_base=opts.cbase,
            channel_max=opts.cmax,
            fused_modconv_default='inference_only',
            use_noise=True
        )  # ! close noise injection? since noise_mode='none' in eg3d

    logger.log("creating encoder and NSR decoder...")
    auto_encoder = create_3DAE_model(
        **args_to_dict(args,
                       encoder_and_nsr_defaults().keys()))

    auto_encoder.to(device)
    auto_encoder.eval()

    # * load G_ema modules into autoencoder
    # * clone G_ema.decoder to auto_encoder triplane
    # logger.log("AE triplane decoder reuses G_ema decoder...")
    # auto_encoder.decoder.register_buffer('w_avg', G_ema.backbone.mapping.w_avg)

    # auto_encoder.decoder.triplane_decoder.decoder.load_state_dict(  # type: ignore
    #     G_ema.decoder.state_dict())  # type: ignore

    # set grad=False in this manner suppresses the DDP forward no grad error.
    logger.log("freeze triplane decoder...")
    for param in auto_encoder.decoder.triplane_decoder.parameters(
    ):  # type: ignore
        # for param in auto_encoder.decoder.triplane_decoder.decoder.parameters(): # type: ignore
        param.requires_grad_(False)

    # if args.sr_training:

    #     logger.log("AE triplane decoder reuses G_ema SR module...")
    #     # auto_encoder.decoder.triplane_decoder.superresolution.load_state_dict(  # type: ignore
    #     #     G_ema.superresolution.state_dict())  # type: ignore

    #     # set grad=False in this manner suppresses the DDP forward no grad error.
    # logger.log("freeze SR module...")
    # for param in auto_encoder.decoder.superresolution.parameters(): # type: ignore
    #     param.requires_grad_(False)

    #     # del G_ema
    #     th.cuda.empty_cache()

    if args.cfg in ('afhq', 'ffhq'):

        if args.sr_training:

            logger.log("AE triplane decoder reuses G_ema SR module...")
            auto_encoder.decoder.triplane_decoder.superresolution.load_state_dict(  # type: ignore
                G_ema.superresolution.state_dict())  # type: ignore

            # set grad=False in this manner suppresses the DDP forward no grad error.
            for param in auto_encoder.decoder.triplane_decoder.superresolution.parameters(
            ):  # type: ignore
                param.requires_grad_(False)

        # ! load data
        logger.log("creating eg3d data loader...")
        training_set_kwargs, dataset_name = init_dataset_kwargs(
            data=args.data_dir,
            class_name='datasets.eg3d_dataset.ImageFolderDataset'
        )  # only load pose here
        # if args.cond and not training_set_kwargs.use_labels:
        # raise Exception('check here')

        # training_set_kwargs.use_labels = args.cond
        training_set_kwargs.use_labels = True
        training_set_kwargs.xflip = True
        training_set_kwargs.random_seed = SEED
        # desc = f'{args.cfg:s}-{dataset_name:s}-gpus{c.num_gpus:d}-batch{c.batch_size:d}-gamma{c.loss_kwargs.r1_gamma:g}'

        # * construct ffhq/afhq dataset
        training_set = dnnlib.util.construct_class_by_name(
            **training_set_kwargs)  # subclass of training.dataset.Dataset

        training_set = dnnlib.util.construct_class_by_name(
            **training_set_kwargs)  # subclass of training.dataset.Dataset

        training_set_sampler = InfiniteSampler(
            dataset=training_set,
            rank=dist_util.get_rank(),
            num_replicas=dist_util.get_world_size(),
            seed=SEED)

        data = iter(
            th.utils.data.DataLoader(
                dataset=training_set,
                sampler=training_set_sampler,
                batch_size=args.batch_size,
                pin_memory=True,
                num_workers=args.num_workers,
            ))
        #  prefetch_factor=2))

        eval_data = th.utils.data.DataLoader(dataset=Subset(
            training_set, np.arange(10)),
                                             batch_size=args.eval_batch_size,
                                             num_workers=1)

    else:

        logger.log("creating data loader...")
        # TODO, load shapenet data
        # data = load_data(
        # st() mark
        if args.overfitting:
            logger.log("create overfitting memory dataset")
            data = load_memory_data(
                file_path=args.eval_data_dir,
                batch_size=args.batch_size,
                reso=args.image_size,
                reso_encoder=args.image_size_encoder,  # 224 -> 128
                num_workers=args.num_workers,
                load_depth=True  # for evaluation
            )
        else:
            logger.log("create all instances dataset")
            # st() mark
            data = load_data(
                file_path=args.data_dir,
                batch_size=args.batch_size,
                reso=args.image_size,
                reso_encoder=args.image_size_encoder,  # 224 -> 128
                num_workers=args.num_workers,
                load_depth=True,
                preprocess=auto_encoder.preprocess,  # clip
                dataset_size=args.dataset_size,
                # load_depth=True # for evaluation
            )
            # st() mark
        eval_data = load_eval_data(
            file_path=args.eval_data_dir,
            batch_size=args.eval_batch_size,
            reso=args.image_size,
            reso_encoder=args.image_size_encoder,  # 224 -> 128
            num_workers=args.num_workers,
            load_depth=True  # for evaluation
        )

    # let all processes sync up before starting with a new epoch of training

    if dist_util.get_rank() == 0:
        with open(os.path.join(args.logdir, 'args.json'), 'w') as f:
            json.dump(vars(args), f, indent=2)

    args.schedule_sampler = create_named_schedule_sampler(
        args.schedule_sampler, diffusion)

    opt = dnnlib.EasyDict(args_to_dict(args, loss_defaults().keys()))
    loss_class = E3DGELossClass(device, opt).to(device)

    logger.log("training...")

    TrainLoop = {
        'adm': nsr.TrainLoop3DDiffusion,
        'dit': nsr.TrainLoop3DDiffusionDiT,
        'ssd': nsr.TrainLoop3DDiffusionSingleStage,
        # 'ssd_cvD': nsr.TrainLoop3DDiffusionSingleStagecvD,
        'ssd_cvD_sds': nsr.TrainLoop3DDiffusionSingleStagecvDSDS,
        'ssd_cvd_sds_no_separate_sds_step':
        nsr.TrainLoop3DDiffusionSingleStagecvDSDS_sdswithrec,
        'vpsde_lsgm_noD': nsr.lsgm.TrainLoop3DDiffusionLSGM_noD,  # use vpsde
        # 'vpsde_lsgm': nsr.TrainLoop3DDiffusionLSGM, # use vpsde
        # 'vpsde': nsr.TrainLoop3DDiffusion_vpsde,
    }[args.trainer_name]

    if 'vpsde' in args.trainer_name:
        sde_diffusion = make_sde_diffusion(
            dnnlib.EasyDict(
                args_to_dict(args,
                             continuous_diffusion_defaults().keys())))
        assert args.mixed_prediction, 'enable mixed_prediction by default'
        logger.log('create VPSDE diffusion.')
    else:
        sde_diffusion = None

    dist_util.synchronize()

    TrainLoop(rec_model=auto_encoder,
              denoise_model=denoise_model,
              diffusion=diffusion,
              sde_diffusion=sde_diffusion,
              loss_class=loss_class,
              data=data,
              eval_data=eval_data,
              **vars(args)).run_loop()


def create_argparser(**kwargs):
    # defaults.update(model_and_diffusion_defaults())

    defaults = dict(
        dataset_size=-1,
        diffusion_input_size=-1,
        trainer_name='adm',
        use_amp=False,
        triplane_scaling_divider=1.0,  # divide by this value
        overfitting=False,
        num_workers=4,
        image_size=128,
        image_size_encoder=224,
        iterations=150000,
        schedule_sampler="uniform",
        anneal_lr=False,
        lr=5e-5,
        weight_decay=0.0,
        lr_anneal_steps=0,
        batch_size=1,
        eval_batch_size=12,
        microbatch=-1,  # -1 disables microbatches
        ema_rate="0.9999",  # comma-separated list of EMA values
        log_interval=50,
        eval_interval=2500,
        save_interval=10000,
        resume_checkpoint="",
        resume_checkpoint_EG3D="",
        use_fp16=False,
        fp16_scale_growth=1e-3,
        data_dir="",
        eval_data_dir="",
        # load_depth=False, # TODO
        logdir="/mnt/lustre/yslan/logs/nips23/",
        load_submodule_name='',  # for loading pretrained auto_encoder model
        ignore_resume_opt=False,
        # freeze_ae=False,
        denoised_ae=True,
    )

    defaults.update(model_and_diffusion_defaults())
    defaults.update(continuous_diffusion_defaults())
    defaults.update(encoder_and_nsr_defaults())  # type: ignore
    defaults.update(loss_defaults())

    parser = argparse.ArgumentParser()
    add_dict_to_argparser(parser, defaults)

    return parser


if __name__ == "__main__":
    # os.environ["TORCH_CPP_LOG_LEVEL"] = "INFO"
    # os.environ["NCCL_DEBUG"] = "INFO"

    os.environ[
        "TORCH_DISTRIBUTED_DEBUG"] = "DETAIL"  # set to DETAIL for runtime logging.

    args = create_argparser().parse_args()
    args.local_rank = int(os.environ["LOCAL_RANK"])
    args.gpus = th.cuda.device_count()

    # opts = dnnlib.EasyDict(vars(args))  # compatiable with triplane original settings
    # opts = args
    args.rendering_kwargs = rendering_options_defaults(args)

    # Launch processes.
    logger.log('Launching processes...')

    logger.log('Available devices ', th.cuda.device_count())
    logger.log('Current cuda device ', th.cuda.current_device())
    # logger.log('GPU Device name:', th.cuda.get_device_name(th.cuda.current_device()))

    try:
        training_loop(args)
    # except KeyboardInterrupt as e:
    except Exception as e:
        # print(e)
        traceback.print_exc()
        dist_util.cleanup()  # clean port and socket when ctrl+c