# encoding: utf-8
"""
@author:  sherlock
@contact: sherlockliao01@gmail.com
"""

import logging
import sys

sys.path.append('.')

from fastreid.config import get_cfg

from fastreid.engine import default_argument_parser, default_setup, launch
from fastreid.utils.checkpoint import Checkpointer
from fastreid.engine import DefaultTrainer
from fastreid.data import build_reid_train_loader

from naic import *


class Trainer(DefaultTrainer):
    @classmethod
    def build_train_loader(cls, cfg):
        logger = logging.getLogger("fastreid.naic20")
        logger.info("Prepare NAIC20 competition trainset")
        return build_reid_train_loader(cfg, rm_lt=cfg.DATASETS.RM_LT)


class Committer(DefaultTrainer):
    @classmethod
    def build_evaluator(cls, cfg, dataset_name, output_dir=None):
        data_loader, num_query = cls.build_test_loader(cfg, dataset_name)
        return data_loader, NaicEvaluator(cfg, num_query, output_dir)


def setup(args):
    """
    Create configs and perform basic setups.
    """
    cfg = get_cfg()
    add_naic_config(cfg)
    cfg.merge_from_file(args.config_file)
    cfg.merge_from_list(args.opts)
    cfg.freeze()
    default_setup(cfg, args)
    return cfg


def main(args):
    cfg = setup(args)

    if args.eval_only:
        cfg.defrost()
        cfg.MODEL.BACKBONE.PRETRAIN = False
        model = Trainer.build_model(cfg)

        Checkpointer(model, save_dir=cfg.OUTPUT_DIR).load(cfg.MODEL.WEIGHTS)  # load trained model

        if args.commit:
            res = Committer.test(cfg, model)
        else:
            res = Trainer.test(cfg, model)

        return res

    trainer = Trainer(cfg)

    trainer.resume_or_load(resume=args.resume)
    return trainer.train()


if __name__ == "__main__":
    parser = default_argument_parser()
    parser.add_argument("--commit", action="store_true", help="submission testing results")
    args = parser.parse_args()

    print("Command Line Args:", args)
    launch(
        main,
        args.num_gpus,
        num_machines=args.num_machines,
        machine_rank=args.machine_rank,
        dist_url=args.dist_url,
        args=(args,),
    )