# Copyright (c) OpenMMLab. All rights reserved.
import argparse
import os
import os.path as osp

from mmengine.config import Config, DictAction
from mmengine.registry import RUNNERS
from mmengine.runner import Runner


def parse_args():
    parser = argparse.ArgumentParser(description='Test (and eval) a model')
    parser.add_argument('config', help='Test config file path')
    parser.add_argument('checkpoint', help='Checkpoint file')
    parser.add_argument(
        '--work-dir',
        help='The directory to save the file containing evaluation metrics')
    parser.add_argument(
        '--save-preds',
        action='store_true',
        help='Dump predictions to a pickle file for offline evaluation')
    parser.add_argument(
        '--show', action='store_true', help='Show prediction results')
    parser.add_argument(
        '--show-dir',
        help='Directory where painted images will be saved. '
        'If specified, it will be automatically saved '
        'to the work_dir/timestamp/show_dir')
    parser.add_argument(
        '--wait-time', type=float, default=2, help='The interval of show (s)')
    parser.add_argument(
        '--cfg-options',
        nargs='+',
        action=DictAction,
        help='Override some settings in the used config, the key-value pair '
        'in xxx=yyy format will be merged into config file. If the value to '
        'be overwritten is a list, it should be like key="[a,b]" or key=a,b '
        'It also allows nested list/tuple values, e.g. key="[(a,b),(c,d)]" '
        'Note that the quotation marks are necessary and that no white space '
        'is allowed.')
    parser.add_argument(
        '--launcher',
        choices=['none', 'pytorch', 'slurm', 'mpi'],
        default='none',
        help='Job launcher')
    parser.add_argument(
        '--tta', action='store_true', help='Test time augmentation')
    # When using PyTorch version >= 2.0.0, the `torch.distributed.launch`
    # will pass the `--local-rank` parameter to `tools/test.py` instead
    # of `--local_rank`.
    parser.add_argument('--local_rank', '--local-rank', type=int, default=0)
    args = parser.parse_args()
    if 'LOCAL_RANK' not in os.environ:
        os.environ['LOCAL_RANK'] = str(args.local_rank)
    return args


def trigger_visualization_hook(cfg, args):
    default_hooks = cfg.default_hooks
    if 'visualization' in default_hooks:
        visualization_hook = default_hooks['visualization']
        # Turn on visualization
        visualization_hook['enable'] = True
        visualization_hook['draw_gt'] = True
        visualization_hook['draw_pred'] = True
        if args.show:
            visualization_hook['show'] = True
            visualization_hook['wait_time'] = args.wait_time
        if args.show_dir:
            cfg.visualizer['save_dir'] = args.show_dir
            cfg.visualizer['vis_backends'] = [dict(type='LocalVisBackend')]
    else:
        raise RuntimeError(
            'VisualizationHook must be included in default_hooks.'
            'refer to usage '
            '"visualization=dict(type=\'VisualizationHook\')"')

    return cfg


def main():
    args = parse_args()

    # load config
    cfg = Config.fromfile(args.config)
    cfg.launcher = args.launcher
    if args.cfg_options is not None:
        cfg.merge_from_dict(args.cfg_options)

    # work_dir is determined in this priority: CLI > segment in file > filename
    if args.work_dir is not None:
        # update configs according to CLI args if args.work_dir is not None
        cfg.work_dir = args.work_dir
    elif cfg.get('work_dir', None) is None:
        # use config filename as default work_dir if cfg.work_dir is None
        cfg.work_dir = osp.join('./work_dirs',
                                osp.splitext(osp.basename(args.config))[0])

    cfg.load_from = args.checkpoint

    # TODO: It will be supported after refactoring the visualizer
    if args.show and args.show_dir:
        raise NotImplementedError('--show and --show-dir cannot be set '
                                  'at the same time')

    if args.show or args.show_dir:
        cfg = trigger_visualization_hook(cfg, args)

    if args.tta:
        cfg.test_dataloader.dataset.pipeline = cfg.tta_pipeline
        cfg.tta_model.module = cfg.model
        cfg.model = cfg.tta_model

    # save predictions
    if args.save_preds:
        dump_metric = dict(
            type='DumpResults',
            out_file_path=osp.join(
                cfg.work_dir,
                f'{osp.basename(args.checkpoint)}_predictions.pkl'))
        if isinstance(cfg.test_evaluator, (list, tuple)):
            cfg.test_evaluator = list(cfg.test_evaluator)
            cfg.test_evaluator.append(dump_metric)
        else:
            cfg.test_evaluator = [cfg.test_evaluator, dump_metric]

    # build the runner from config
    if 'runner_type' not in cfg:
        # build the default runner
        runner = Runner.from_cfg(cfg)
    else:
        # build customized runner from the registry
        # if 'runner_type' is set in the cfg
        runner = RUNNERS.build(cfg)

    # start testing
    runner.test()


if __name__ == '__main__':
    main()