# Copyright (c) OpenMMLab. All rights reserved.
from os.path import dirname, exists, join
from unittest.mock import Mock

import pytest

from mmdet.core import BitmapMasks, PolygonMasks
from mmdet.datasets.builder import DATASETS
from mmdet.datasets.utils import NumClassCheckHook


def _get_config_directory():
    """Find the predefined detector config directory."""
    try:
        # Assume we are running in the source mmdetection repo
        repo_dpath = dirname(dirname(__file__))
        repo_dpath = join(repo_dpath, '..')
    except NameError:
        # For IPython development when this __file__ is not defined
        import mmdet
        repo_dpath = dirname(dirname(mmdet.__file__))
    config_dpath = join(repo_dpath, 'configs')
    if not exists(config_dpath):
        raise Exception('Cannot find config path')
    return config_dpath


def _check_numclasscheckhook(detector, config_mod):
    dummy_runner = Mock()
    dummy_runner.model = detector

    def get_dataset_name_classes(dataset):
        # deal with `RepeatDataset`,`ConcatDataset`,`ClassBalancedDataset`..
        if isinstance(dataset, (list, tuple)):
            dataset = dataset[0]
        while ('dataset' in dataset):
            dataset = dataset['dataset']
            # ConcatDataset
            if isinstance(dataset, (list, tuple)):
                dataset = dataset[0]
        return dataset['type'], dataset.get('classes', None)

    compatible_check = NumClassCheckHook()
    dataset_name, CLASSES = get_dataset_name_classes(
        config_mod['data']['train'])
    if CLASSES is None:
        CLASSES = DATASETS.get(dataset_name).CLASSES
    dummy_runner.data_loader.dataset.CLASSES = CLASSES
    compatible_check.before_train_epoch(dummy_runner)

    dummy_runner.data_loader.dataset.CLASSES = None
    compatible_check.before_train_epoch(dummy_runner)

    dataset_name, CLASSES = get_dataset_name_classes(config_mod['data']['val'])
    if CLASSES is None:
        CLASSES = DATASETS.get(dataset_name).CLASSES
    dummy_runner.data_loader.dataset.CLASSES = CLASSES
    compatible_check.before_val_epoch(dummy_runner)
    dummy_runner.data_loader.dataset.CLASSES = None
    compatible_check.before_val_epoch(dummy_runner)


def _check_roi_head(config, head):
    # check consistency between head_config and roi_head
    assert config['type'] == head.__class__.__name__

    # check roi_align
    bbox_roi_cfg = config.bbox_roi_extractor
    bbox_roi_extractor = head.bbox_roi_extractor
    _check_roi_extractor(bbox_roi_cfg, bbox_roi_extractor)

    # check bbox head infos
    bbox_cfg = config.bbox_head
    bbox_head = head.bbox_head
    _check_bbox_head(bbox_cfg, bbox_head)

    if head.with_mask:
        # check roi_align
        if config.mask_roi_extractor:
            mask_roi_cfg = config.mask_roi_extractor
            mask_roi_extractor = head.mask_roi_extractor
            _check_roi_extractor(mask_roi_cfg, mask_roi_extractor,
                                 bbox_roi_extractor)

        # check mask head infos
        mask_head = head.mask_head
        mask_cfg = config.mask_head
        _check_mask_head(mask_cfg, mask_head)

    # check arch specific settings, e.g., cascade/htc
    if config['type'] in ['CascadeRoIHead', 'HybridTaskCascadeRoIHead']:
        assert config.num_stages == len(head.bbox_head)
        assert config.num_stages == len(head.bbox_roi_extractor)

        if head.with_mask:
            assert config.num_stages == len(head.mask_head)
            assert config.num_stages == len(head.mask_roi_extractor)

    elif config['type'] in ['MaskScoringRoIHead']:
        assert (hasattr(head, 'mask_iou_head')
                and head.mask_iou_head is not None)
        mask_iou_cfg = config.mask_iou_head
        mask_iou_head = head.mask_iou_head
        assert (mask_iou_cfg.fc_out_channels ==
                mask_iou_head.fc_mask_iou.in_features)

    elif config['type'] in ['GridRoIHead']:
        grid_roi_cfg = config.grid_roi_extractor
        grid_roi_extractor = head.grid_roi_extractor
        _check_roi_extractor(grid_roi_cfg, grid_roi_extractor,
                             bbox_roi_extractor)

        config.grid_head.grid_points = head.grid_head.grid_points


def _check_roi_extractor(config, roi_extractor, prev_roi_extractor=None):
    import torch.nn as nn
    # Separate roi_extractor and prev_roi_extractor checks for flexibility
    if isinstance(roi_extractor, nn.ModuleList):
        roi_extractor = roi_extractor[0]
    if prev_roi_extractor and isinstance(prev_roi_extractor, nn.ModuleList):
        prev_roi_extractor = prev_roi_extractor[0]

    assert (len(config.featmap_strides) == len(roi_extractor.roi_layers))
    assert (config.out_channels == roi_extractor.out_channels)
    from torch.nn.modules.utils import _pair
    assert (_pair(config.roi_layer.output_size) ==
            roi_extractor.roi_layers[0].output_size)

    if 'use_torchvision' in config.roi_layer:
        assert (config.roi_layer.use_torchvision ==
                roi_extractor.roi_layers[0].use_torchvision)
    elif 'aligned' in config.roi_layer:
        assert (
            config.roi_layer.aligned == roi_extractor.roi_layers[0].aligned)

    if prev_roi_extractor:
        assert (roi_extractor.roi_layers[0].aligned ==
                prev_roi_extractor.roi_layers[0].aligned)
        assert (roi_extractor.roi_layers[0].use_torchvision ==
                prev_roi_extractor.roi_layers[0].use_torchvision)


def _check_mask_head(mask_cfg, mask_head):
    import torch.nn as nn
    if isinstance(mask_cfg, list):
        for single_mask_cfg, single_mask_head in zip(mask_cfg, mask_head):
            _check_mask_head(single_mask_cfg, single_mask_head)
    elif isinstance(mask_head, nn.ModuleList):
        for single_mask_head in mask_head:
            _check_mask_head(mask_cfg, single_mask_head)
    else:
        assert mask_cfg['type'] == mask_head.__class__.__name__
        assert mask_cfg.in_channels == mask_head.in_channels
        class_agnostic = mask_cfg.get('class_agnostic', False)
        out_dim = (1 if class_agnostic else mask_cfg.num_classes)
        if hasattr(mask_head, 'conv_logits'):
            assert (mask_cfg.conv_out_channels ==
                    mask_head.conv_logits.in_channels)
            assert mask_head.conv_logits.out_channels == out_dim
        else:
            assert mask_cfg.fc_out_channels == mask_head.fc_logits.in_features
            assert (mask_head.fc_logits.out_features == out_dim *
                    mask_head.output_area)


def _check_bbox_head(bbox_cfg, bbox_head):
    import torch.nn as nn
    if isinstance(bbox_cfg, list):
        for single_bbox_cfg, single_bbox_head in zip(bbox_cfg, bbox_head):
            _check_bbox_head(single_bbox_cfg, single_bbox_head)
    elif isinstance(bbox_head, nn.ModuleList):
        for single_bbox_head in bbox_head:
            _check_bbox_head(bbox_cfg, single_bbox_head)
    else:
        assert bbox_cfg['type'] == bbox_head.__class__.__name__
        if bbox_cfg['type'] == 'SABLHead':
            assert bbox_cfg.cls_in_channels == bbox_head.cls_in_channels
            assert bbox_cfg.reg_in_channels == bbox_head.reg_in_channels

            cls_out_channels = bbox_cfg.get('cls_out_channels', 1024)
            assert (cls_out_channels == bbox_head.fc_cls.in_features)
            assert (bbox_cfg.num_classes + 1 == bbox_head.fc_cls.out_features)

        elif bbox_cfg['type'] == 'DIIHead':
            assert bbox_cfg['num_ffn_fcs'] == bbox_head.ffn.num_fcs
            # 3 means FC and LN and Relu
            assert bbox_cfg['num_cls_fcs'] == len(bbox_head.cls_fcs) // 3
            assert bbox_cfg['num_reg_fcs'] == len(bbox_head.reg_fcs) // 3
            assert bbox_cfg['in_channels'] == bbox_head.in_channels
            assert bbox_cfg['in_channels'] == bbox_head.fc_cls.in_features
            assert bbox_cfg['in_channels'] == bbox_head.fc_reg.in_features
            assert bbox_cfg['in_channels'] == bbox_head.attention.embed_dims
            assert bbox_cfg[
                'feedforward_channels'] == bbox_head.ffn.feedforward_channels

        else:
            assert bbox_cfg.in_channels == bbox_head.in_channels
            with_cls = bbox_cfg.get('with_cls', True)

            if with_cls:
                fc_out_channels = bbox_cfg.get('fc_out_channels', 2048)
                assert (fc_out_channels == bbox_head.fc_cls.in_features)
                if bbox_head.custom_cls_channels:
                    assert (bbox_head.loss_cls.get_cls_channels(
                        bbox_head.num_classes) == bbox_head.fc_cls.out_features
                            )
                else:
                    assert (bbox_cfg.num_classes +
                            1 == bbox_head.fc_cls.out_features)
            with_reg = bbox_cfg.get('with_reg', True)
            if with_reg:
                out_dim = (4 if bbox_cfg.reg_class_agnostic else 4 *
                           bbox_cfg.num_classes)
                assert bbox_head.fc_reg.out_features == out_dim


def _check_anchorhead(config, head):
    # check consistency between head_config and roi_head
    assert config['type'] == head.__class__.__name__
    assert config.in_channels == head.in_channels

    num_classes = (
        config.num_classes -
        1 if config.loss_cls.get('use_sigmoid', False) else config.num_classes)
    if config['type'] == 'ATSSHead':
        assert (config.feat_channels == head.atss_cls.in_channels)
        assert (config.feat_channels == head.atss_reg.in_channels)
        assert (config.feat_channels == head.atss_centerness.in_channels)
    elif config['type'] == 'SABLRetinaHead':
        assert (config.feat_channels == head.retina_cls.in_channels)
        assert (config.feat_channels == head.retina_bbox_reg.in_channels)
        assert (config.feat_channels == head.retina_bbox_cls.in_channels)
    else:
        assert (config.in_channels == head.conv_cls.in_channels)
        assert (config.in_channels == head.conv_reg.in_channels)
        assert (head.conv_cls.out_channels == num_classes * head.num_anchors)
        assert head.fc_reg.out_channels == 4 * head.num_anchors


# Only tests a representative subset of configurations
# TODO: test pipelines using Albu, current Albu throw None given empty GT
@pytest.mark.parametrize(
    'config_rpath',
    [
        'wider_face/ssd300_wider_face.py',
        'pascal_voc/ssd300_voc0712.py',
        'pascal_voc/ssd512_voc0712.py',
        # 'albu_example/mask_rcnn_r50_fpn_1x.py',
        'foveabox/fovea_align_r50_fpn_gn-head_mstrain_640-800_4x4_2x_coco.py',
        'mask_rcnn/mask_rcnn_r50_caffe_fpn_mstrain-poly_1x_coco.py',
        'mask_rcnn/mask_rcnn_r50_caffe_fpn_mstrain_1x_coco.py',
        'fp16/mask_rcnn_r50_fpn_fp16_1x_coco.py'
    ])
def test_config_data_pipeline(config_rpath):
    """Test whether the data pipeline is valid and can process corner cases.

    CommandLine:
        xdoctest -m tests/test_runtime/
            test_config.py test_config_build_data_pipeline
    """
    from mmcv import Config
    from mmdet.datasets.pipelines import Compose
    import numpy as np

    config_dpath = _get_config_directory()
    print(f'Found config_dpath = {config_dpath}')

    def dummy_masks(h, w, num_obj=3, mode='bitmap'):
        assert mode in ('polygon', 'bitmap')
        if mode == 'bitmap':
            masks = np.random.randint(0, 2, (num_obj, h, w), dtype=np.uint8)
            masks = BitmapMasks(masks, h, w)
        else:
            masks = []
            for i in range(num_obj):
                masks.append([])
                masks[-1].append(
                    np.random.uniform(0, min(h - 1, w - 1), (8 + 4 * i, )))
                masks[-1].append(
                    np.random.uniform(0, min(h - 1, w - 1), (10 + 4 * i, )))
            masks = PolygonMasks(masks, h, w)
        return masks

    config_fpath = join(config_dpath, config_rpath)
    cfg = Config.fromfile(config_fpath)

    # remove loading pipeline
    loading_pipeline = cfg.train_pipeline.pop(0)
    loading_ann_pipeline = cfg.train_pipeline.pop(0)
    cfg.test_pipeline.pop(0)

    train_pipeline = Compose(cfg.train_pipeline)
    test_pipeline = Compose(cfg.test_pipeline)

    print(f'Building data pipeline, config_fpath = {config_fpath}')

    print(f'Test training data pipeline: \n{train_pipeline!r}')
    img = np.random.randint(0, 255, size=(888, 666, 3), dtype=np.uint8)
    if loading_pipeline.get('to_float32', False):
        img = img.astype(np.float32)
    mode = 'bitmap' if loading_ann_pipeline.get('poly2mask',
                                                True) else 'polygon'
    results = dict(
        filename='test_img.png',
        ori_filename='test_img.png',
        img=img,
        img_shape=img.shape,
        ori_shape=img.shape,
        gt_bboxes=np.array([[35.2, 11.7, 39.7, 15.7]], dtype=np.float32),
        gt_labels=np.array([1], dtype=np.int64),
        gt_masks=dummy_masks(img.shape[0], img.shape[1], mode=mode),
    )
    results['img_fields'] = ['img']
    results['bbox_fields'] = ['gt_bboxes']
    results['mask_fields'] = ['gt_masks']
    output_results = train_pipeline(results)
    assert output_results is not None

    print(f'Test testing data pipeline: \n{test_pipeline!r}')
    results = dict(
        filename='test_img.png',
        ori_filename='test_img.png',
        img=img,
        img_shape=img.shape,
        ori_shape=img.shape,
        gt_bboxes=np.array([[35.2, 11.7, 39.7, 15.7]], dtype=np.float32),
        gt_labels=np.array([1], dtype=np.int64),
        gt_masks=dummy_masks(img.shape[0], img.shape[1], mode=mode),
    )
    results['img_fields'] = ['img']
    results['bbox_fields'] = ['gt_bboxes']
    results['mask_fields'] = ['gt_masks']
    output_results = test_pipeline(results)
    assert output_results is not None

    # test empty GT
    print('Test empty GT with training data pipeline: '
          f'\n{train_pipeline!r}')
    results = dict(
        filename='test_img.png',
        ori_filename='test_img.png',
        img=img,
        img_shape=img.shape,
        ori_shape=img.shape,
        gt_bboxes=np.zeros((0, 4), dtype=np.float32),
        gt_labels=np.array([], dtype=np.int64),
        gt_masks=dummy_masks(img.shape[0], img.shape[1], num_obj=0, mode=mode),
    )
    results['img_fields'] = ['img']
    results['bbox_fields'] = ['gt_bboxes']
    results['mask_fields'] = ['gt_masks']
    output_results = train_pipeline(results)
    assert output_results is not None

    print(f'Test empty GT with testing data pipeline: \n{test_pipeline!r}')
    results = dict(
        filename='test_img.png',
        ori_filename='test_img.png',
        img=img,
        img_shape=img.shape,
        ori_shape=img.shape,
        gt_bboxes=np.zeros((0, 4), dtype=np.float32),
        gt_labels=np.array([], dtype=np.int64),
        gt_masks=dummy_masks(img.shape[0], img.shape[1], num_obj=0, mode=mode),
    )
    results['img_fields'] = ['img']
    results['bbox_fields'] = ['gt_bboxes']
    results['mask_fields'] = ['gt_masks']
    output_results = test_pipeline(results)
    assert output_results is not None
