File size: 3,833 Bytes
aef1f5a
3c4c67b
 
 
aef1f5a
262b3cb
 
80cbb1a
3c4c67b
a544a50
 
3c4c67b
 
 
aef1f5a
3c4c67b
a544a50
 
3c4c67b
aef1f5a
 
363ba14
 
262b3cb
363ba14
 
 
 
 
 
3c4c67b
aef1f5a
 
3c4c67b
 
aef1f5a
3c4c67b
 
aef1f5a
3c4c67b
363ba14
 
 
 
 
 
 
3c4c67b
aef1f5a
 
3c4c67b
 
aef1f5a
 
 
 
3c4c67b
363ba14
 
 
 
3c4c67b
aef1f5a
 
3c4c67b
aef1f5a
 
 
 
 
 
 
 
 
 
 
 
a544a50
26f14be
 
 
aef1f5a
 
 
 
 
26f14be
 
 
aef1f5a
a544a50
 
aef1f5a
 
 
 
 
a544a50
aef1f5a
 
 
 
 
 
 
a544a50
 
aef1f5a
 
 
 
 
 
 
 
 
 
a544a50
 
 
 
 
 
 
 
 
 
 
 
 
 
aef1f5a
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
"""Provide typed access to ISLES24 cases."""

from __future__ import annotations

import re
from dataclasses import dataclass
from pathlib import Path  # noqa: TC003
from typing import TYPE_CHECKING, Self

from stroke_deepisles_demo.core.logging import get_logger

if TYPE_CHECKING:
    from collections.abc import Iterator

    from stroke_deepisles_demo.core.types import CaseFiles

logger = get_logger(__name__)


@dataclass
class LocalDataset:
    """File-based dataset for local ISLES24 data.

    Can be used as a context manager for consistency with HuggingFaceDatasetWrapper,
    though no cleanup is needed for local files.

    Example:
        with build_local_dataset(path) as ds:
            case = ds.get_case(0)
    """

    data_dir: Path
    cases: dict[str, CaseFiles]  # subject_id -> files

    def __len__(self) -> int:
        return len(self.cases)

    def __iter__(self) -> Iterator[str]:
        return iter(self.cases.keys())

    def __enter__(self) -> Self:
        return self

    def __exit__(self, *args: object) -> None:
        # No cleanup needed for local files
        pass

    def list_case_ids(self) -> list[str]:
        """Return sorted list of subject IDs."""
        return sorted(self.cases.keys())

    def get_case(self, case_id: str | int) -> CaseFiles:
        """Get files for a case by ID or index."""
        if isinstance(case_id, int):
            case_id = self.list_case_ids()[case_id]
        return self.cases[case_id]

    def cleanup(self) -> None:
        """No-op for local dataset (files are not temporary)."""
        pass


# Subject ID extraction
SUBJECT_PATTERN = re.compile(r"sub-(stroke\d{4})_ses-\d+_.*\.nii\.gz")


def parse_subject_id(filename: str) -> str | None:
    """Extract subject ID from BIDS filename."""
    match = SUBJECT_PATTERN.match(filename)
    return f"sub-{match.group(1)}" if match else None


def build_local_dataset(data_dir: Path) -> LocalDataset:
    """
    Scan directory and build case mapping.

    Matches DWI + ADC + Mask files by subject ID.
    Logs warnings for incomplete cases that are skipped.

    Raises:
        FileNotFoundError: If DWI subdirectory (Images-DWI) is missing
    """
    dwi_dir = data_dir / "Images-DWI"
    adc_dir = data_dir / "Images-ADC"
    mask_dir = data_dir / "Masks"

    if not dwi_dir.exists():
        raise FileNotFoundError(f"Data directory not found or invalid: {dwi_dir}")

    cases: dict[str, CaseFiles] = {}
    skipped_no_subject_id = 0
    skipped_no_adc: list[str] = []

    # Scan DWI files to get subject IDs
    for dwi_file in dwi_dir.glob("*.nii.gz"):
        subject_id = parse_subject_id(dwi_file.name)
        if not subject_id:
            skipped_no_subject_id += 1
            continue

        # Find matching ADC and Mask
        adc_file = adc_dir / dwi_file.name.replace("_dwi.", "_adc.")
        mask_file = mask_dir / dwi_file.name.replace("_dwi.", "_lesion-msk.")

        if not adc_file.exists():
            skipped_no_adc.append(subject_id)
            continue

        case_files: CaseFiles = {
            "dwi": dwi_file,
            "adc": adc_file,
        }
        if mask_file.exists():
            case_files["ground_truth"] = mask_file

        cases[subject_id] = case_files

    # Log skipped cases for debugging
    if skipped_no_subject_id > 0:
        logger.warning(
            "Skipped %d DWI files: could not parse subject ID from filename",
            skipped_no_subject_id,
        )
    if skipped_no_adc:
        logger.warning(
            "Skipped %d cases missing ADC file: %s",
            len(skipped_no_adc),
            ", ".join(skipped_no_adc[:5]) + ("..." if len(skipped_no_adc) > 5 else ""),
        )

    logger.info("Loaded %d cases from %s", len(cases), data_dir)
    return LocalDataset(data_dir=data_dir, cases=cases)