app.py

import json
from functools import lru_cache
import re
import traceback
from typing import Optional

import gradio as gr
from huggingface_hub import HfApi, hf_hub_download, hf_hub_url
from huggingface_hub.utils import HfHubHTTPError


DEFAULT_REPO_ID = "mlfoundations-cua-dev/human_eval"
IMAGE_EXTENSIONS = (
    ".jpg",
    ".jpeg",
    ".png",
    ".bmp",
    ".gif",
    ".webp",
    ".tif",
    ".tiff",
)
INIT_SCREENSHOT_NAMES = {"intial_screenshot", "initial_screenshot"}
STEP_FILENAME_PATTERN = re.compile(r"^step_(\d+)(?:\.[^.]+)?$", re.IGNORECASE)
TRAJECTORY_FILENAME = "traj.jsonl"


api = HfApi()


@lru_cache(maxsize=16)
def _list_repo_files(repo_id: str) -> list[str]:
    """Return all file paths contained in a Hugging Face dataset repository."""
    return api.list_repo_files(repo_id=repo_id, repo_type="dataset")


def _extract_top_level(repo_id: str) -> tuple[list[str], list[str]]:
    """Split top-level folders and files for the given repository."""
    files = _list_repo_files(repo_id)
    top_level_dirs = sorted({path.split("/", 1)[0] for path in files if "/" in path})
    top_level_files = sorted(path for path in files if "/" not in path)
    return top_level_dirs, top_level_files


def _get_subdirectories(repo_id: str, directory: str) -> list[str]:
    """Return the direct subdirectories of the given directory."""
    if not directory:
        return []

    files = [path for path in _list_repo_files(repo_id) if path.startswith(f"{directory}/")]
    relative_paths = [path[len(directory) + 1 :] for path in files]
    
    # Get immediate subdirectories (first level only)
    child_dirs = sorted({rel.split("/", 1)[0] for rel in relative_paths if "/" in rel})
    
    return child_dirs


def _build_path(*parts) -> str:
    """Join path parts while skipping empty values."""
    return "/".join(part for part in parts if part)


def _image_sort_key(path: str):
    filename = path.rsplit("/", 1)[-1]
    lower_name = filename.lower()

    if any(lower_name.startswith(name) for name in INIT_SCREENSHOT_NAMES):
        return (0, 0)

    match = STEP_FILENAME_PATTERN.match(lower_name)
    if match:
        return (1, int(match.group(1)))

    return (2, lower_name)


def _load_traj_entries(repo_id: str, directory: str) -> list:
    """Load trajectory annotations from traj.jsonl within the given directory."""
    if not directory:
        return []

    traj_path = _build_path(directory, TRAJECTORY_FILENAME)
    repo_files = _list_repo_files(repo_id)

    if traj_path not in repo_files:
        return []

    local_path = hf_hub_download(
        repo_id=repo_id,
        filename=traj_path,
        repo_type="dataset",
    )

    entries: list = []
    with open(local_path, "r", encoding="utf-8") as file:
        for raw_line in file:
            stripped = raw_line.strip()
            if not stripped:
                continue

            parsed = json.loads(stripped)
            if isinstance(parsed, list):
                entries.extend(parsed)
            else:
                entries.append(parsed)

    return entries


def _load_instruction_file(repo_id: str, filepath: str) -> Optional[str]:
    """Download a metadata JSON file and extract its instruction field."""
    local_path = hf_hub_download(
        repo_id=repo_id,
        filename=filepath,
        repo_type="dataset",
    )

    with open(local_path, "r", encoding="utf-8") as file:
        data = json.load(file)

    instruction: Optional[str] = None
    if isinstance(data, dict):
        instruction = data.get("instruction")
    elif isinstance(data, list):
        for entry in data:
            if isinstance(entry, dict) and "instruction" in entry:
                instruction = entry["instruction"]
                break

    if instruction is None:
        return None

    if isinstance(instruction, str):
        return instruction.strip()

    return str(instruction)


def _format_annotation(index: int, annotation) -> str:
    prefix = f"Step {index + 1}"
    if isinstance(annotation, str):
        content = annotation.strip()
    else:
        try:
            content = json.dumps(annotation, ensure_ascii=False)
        except TypeError:
            content = str(annotation)
    return f"{prefix}: {content}" if content else prefix


def _prepare_gallery_items(
    repo_id: str, directory: Optional[str]
) -> tuple[list[tuple[str, str]], list[str], str]:
    """Prepare gallery items, status messages, and instruction text for a directory."""
    if not directory:
        return (
            [],
            ["Select a fifth-level folder to view screenshots."],
            "ℹ️ Instruction will appear once a fifth-level folder is selected.",
        )

    prefix = f"{directory}/"
    files = [path for path in _list_repo_files(repo_id) if path.startswith(prefix)]

    image_files = [
        path
        for path in files
        if "/" not in path[len(prefix) :]
        and path.lower().endswith(IMAGE_EXTENSIONS)
    ]

    sorted_files = sorted(image_files, key=_image_sort_key)
    image_urls = [
        hf_hub_url(repo_id=repo_id, filename=path, repo_type="dataset")
        for path in sorted_files
    ]

    status_lines: list[str] = [
        f"🖼️ Images: {len(image_urls)}",
    ]

    annotations: list = []
    try:
        annotations = _load_traj_entries(repo_id, directory)
    except json.JSONDecodeError as error:
        status_lines.append(f"⚠️ Failed to parse `{TRAJECTORY_FILENAME}`: {error}")
    except Exception as error:  # pragma: no cover - unexpected IO errors
        status_lines.append(f"⚠️ Error loading `{TRAJECTORY_FILENAME}`: {error}")

    status_lines.append(f"📝 Annotations: {len(annotations)}")

    if not image_urls:
        status_lines.append("⚠️ No images found in this folder.")

    if image_urls and not annotations:
        status_lines.append(
            f"⚠️ `{TRAJECTORY_FILENAME}` missing or empty; no annotations to display."
        )

    if annotations and len(annotations) != len(image_urls):
        status_lines.append(
            "⚠️ Mismatch between images and annotations; displaying available pairs."
        )

    folder_name = directory.rsplit("/", 1)[-1]
    metadata_files = [
        path
        for path in files
        if "/" not in path[len(prefix) :]
        and path.lower().endswith(".json")
        and not path.lower().endswith(".jsonl")
    ]

    instruction_markdown = ""
    if metadata_files:
        metadata_files.sort(
            key=lambda path: (
                0
                if path.rsplit("/", 1)[-1].rsplit(".", 1)[0] == folder_name
                else 1,
                path.rsplit("/", 1)[-1].lower(),
            )
        )
        metadata_path = metadata_files[0]
        metadata_filename = metadata_path.rsplit("/", 1)[-1]
        try:
            instruction_value = _load_instruction_file(repo_id, metadata_path)
            if instruction_value:
                instruction_markdown = f"**Instruction:** {instruction_value}"
                status_lines.append("📋 Instruction: loaded")
            else:
                instruction_markdown = (
                    f"⚠️ Instruction missing in `{metadata_filename}`."
                )
                status_lines.append("⚠️ Instruction: missing in metadata.")
        except json.JSONDecodeError as error:
            status_lines.append(
                f"⚠️ Failed to parse `{metadata_filename}`: {error}"
            )
            instruction_markdown = (
                f"⚠️ Unable to parse instruction from `{metadata_filename}`."
            )
        except Exception as error:  # pragma: no cover - unexpected IO errors
            status_lines.append(
                f"⚠️ Error loading `{metadata_filename}`: {error}"
            )
            instruction_markdown = (
                f"⚠️ Unable to load instruction from `{metadata_filename}`."
            )
    else:
        instruction_markdown = "⚠️ Instruction file not found in this folder."
        status_lines.append("⚠️ Instruction: file not found.")

    gallery_items: list[tuple[str, str]] = []
    for idx, url in enumerate(image_urls):
        caption = "No annotation available"
        if idx < len(annotations):
            caption = _format_annotation(idx, annotations[idx])
        gallery_items.append((url, caption))

    return gallery_items, status_lines, instruction_markdown


def _dropdown_update(
    *,
    choices: list[str],
    value: Optional[str],
    label: str,
    filled_info: str,
    empty_info: str,
):
    has_choices = bool(choices)
    return gr.update(
        choices=choices,
        value=value if has_choices else None,
        interactive=has_choices,
        label=label,
        info=filled_info if has_choices else empty_info,
    )


def refresh_repo(repo_id: str):
    try:
        top_dirs, top_files = _extract_top_level(repo_id)
    except HfHubHTTPError as error:
        print(f"[refresh_repo] Hub HTTP error for {repo_id}: {error}", flush=True)
        print(traceback.format_exc(), flush=True)
        return (
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(value=""),
            gr.update(value=[]),
            gr.update(value=""),
            gr.update(value=f"❌ Unable to load repo `{repo_id}`: {error}"),
        )
    except Exception as error:  # pragma: no cover - network and auth edge cases
        print(f"[refresh_repo] Unexpected error for {repo_id}: {error}", flush=True)
        print(traceback.format_exc(), flush=True)
        return (
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(choices=[], value=None, interactive=False),
            gr.update(value=""),
            gr.update(value=[]),
            gr.update(value=""),
            gr.update(value=f"❌ Unexpected error loading `{repo_id}`: {error}"),
        )

    status_lines = [
        f"✅ Loaded `{repo_id}`",
        f"• Top-level folders: {len(top_dirs)}",
    ]

    if top_files:
        status_lines.append(f"• Loose files at root: {len(top_files)}")
    if not top_dirs:
        status_lines.append("• No sub-folders found at root.")

    top_value = top_dirs[0] if top_dirs else None

    second_dirs = _get_subdirectories(repo_id, top_value) if top_value else []
    second_value = second_dirs[0] if second_dirs else None

    third_dirs = (
        _get_subdirectories(repo_id, _build_path(top_value, second_value))
        if second_value
        else []
    )
    third_value = third_dirs[0] if third_dirs else None

    fourth_dirs = (
        _get_subdirectories(repo_id, _build_path(top_value, second_value, third_value))
        if third_value
        else []
    )
    fourth_value = fourth_dirs[0] if fourth_dirs else None

    fifth_dirs = (
        _get_subdirectories(
            repo_id, _build_path(top_value, second_value, third_value, fourth_value)
        )
        if fourth_value
        else []
    )
    fifth_value = fifth_dirs[0] if fifth_dirs else None

    target_directory = (
        _build_path(
            top_value,
            second_value,
            third_value,
            fourth_value,
            fifth_value,
        )
        if fifth_value
        else None
    )
    gallery_items, gallery_status, instruction_markdown = _prepare_gallery_items(
        repo_id, target_directory
    )

    first_dropdown_update = _dropdown_update(
        choices=top_dirs,
        value=top_value,
        label="Top-level folders",
        filled_info="Choose a folder to explore",
        empty_info="No folders found at the repository root",
    )

    second_dropdown_update = _dropdown_update(
        choices=second_dirs,
        value=second_value,
        label="Second-level folders",
        filled_info="Choose a second-level folder",
        empty_info="No subdirectories under the selected folder",
    )

    third_dropdown_update = _dropdown_update(
        choices=third_dirs,
        value=third_value,
        label="Third-level folders",
        filled_info="Choose a third-level folder",
        empty_info="No third-level folders under the selection",
    )

    fourth_dropdown_update = _dropdown_update(
        choices=fourth_dirs,
        value=fourth_value,
        label="Fourth-level folders",
        filled_info="Choose a fourth-level folder",
        empty_info="No fourth-level folders under the selection",
    )

    fifth_dropdown_update = _dropdown_update(
        choices=fifth_dirs,
        value=fifth_value,
        label="Fifth-level folders",
        filled_info="Choose a fifth-level folder",
        empty_info="No fifth-level folders under the selection",
    )

    instruction_update = gr.update(value=instruction_markdown)
    gallery_update = gr.update(value=gallery_items)
    annotation_update = gr.update(value="\n".join(gallery_status))
    status_update = gr.update(value="\n".join(status_lines))

    return (
        first_dropdown_update,
        second_dropdown_update,
        third_dropdown_update,
        fourth_dropdown_update,
        fifth_dropdown_update,
        instruction_update,
        gallery_update,
        annotation_update,
        status_update,
    )


def update_second_dropdown(repo_id: str, top_level_dir: str):
    """Update downstream dropdowns when the top-level selection changes."""
    try:
        if not top_level_dir:
            empty_second = _dropdown_update(
                choices=[],
                value=None,
                label="Second-level folders",
                filled_info="Choose a second-level folder",
                empty_info="Select a top-level folder first",
            )
            empty_third = _dropdown_update(
                choices=[],
                value=None,
                label="Third-level folders",
                filled_info="Choose a third-level folder",
                empty_info="Select a higher-level folder first",
            )
            empty_fourth = _dropdown_update(
                choices=[],
                value=None,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="Select a higher-level folder first",
            )
            empty_fifth = _dropdown_update(
                choices=[],
                value=None,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="Select a higher-level folder first",
            )
            instruction_update = gr.update(
                value="ℹ️ Select a top-level folder to display its instruction."
            )
            gallery_update = gr.update(value=[])
            annotation_update = gr.update(
                value="Select a top-level folder to load screenshots and annotations."
            )
            return (
                empty_second,
                empty_third,
                empty_fourth,
                empty_fifth,
                instruction_update,
                gallery_update,
                annotation_update,
            )

        second_dirs = _get_subdirectories(repo_id, top_level_dir)
        second_value = second_dirs[0] if second_dirs else None

        third_dirs = (
            _get_subdirectories(repo_id, _build_path(top_level_dir, second_value))
            if second_value
            else []
        )
        third_value = third_dirs[0] if third_dirs else None

        fourth_dirs = (
            _get_subdirectories(
                repo_id, _build_path(top_level_dir, second_value, third_value)
            )
            if third_value
            else []
        )
        fourth_value = fourth_dirs[0] if fourth_dirs else None

        fifth_dirs = (
            _get_subdirectories(
                repo_id,
                _build_path(top_level_dir, second_value, third_value, fourth_value),
            )
            if fourth_value
            else []
        )
        fifth_value = fifth_dirs[0] if fifth_dirs else None

        target_directory = (
            _build_path(
                top_level_dir,
                second_value,
                third_value,
                fourth_value,
                fifth_value,
            )
            if fifth_value
            else None
        )
        (
            gallery_items,
            gallery_status,
            instruction_markdown,
        ) = _prepare_gallery_items(repo_id, target_directory)

        return (
            _dropdown_update(
                choices=second_dirs,
                value=second_value,
                label="Second-level folders",
                filled_info="Choose a second-level folder",
                empty_info="No subdirectories under the selected folder",
            ),
            _dropdown_update(
                choices=third_dirs,
                value=third_value,
                label="Third-level folders",
                filled_info="Choose a third-level folder",
                empty_info="No third-level folders under the selection",
            ),
            _dropdown_update(
                choices=fourth_dirs,
                value=fourth_value,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="No fourth-level folders under the selection",
            ),
            _dropdown_update(
                choices=fifth_dirs,
                value=fifth_value,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="No fifth-level folders under the selection",
            ),
            gr.update(value=instruction_markdown),
            gr.update(value=gallery_items),
            gr.update(value="\n".join(gallery_status)),
        )
    except Exception as error:
        print(f"[update_second_dropdown] Error for {repo_id}/{top_level_dir}: {error}", flush=True)
        print(traceback.format_exc(), flush=True)
        empty_second = _dropdown_update(
            choices=[],
            value=None,
            label="Second-level folders",
            filled_info="Choose a second-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_third = _dropdown_update(
            choices=[],
            value=None,
            label="Third-level folders",
            filled_info="Choose a third-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_fourth = _dropdown_update(
            choices=[],
            value=None,
            label="Fourth-level folders",
            filled_info="Choose a fourth-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_fifth = _dropdown_update(
            choices=[],
            value=None,
            label="Fifth-level folders",
            filled_info="Choose a fifth-level folder",
            empty_info="Unable to load subdirectories",
        )
        return (
            empty_second,
            empty_third,
            empty_fourth,
            empty_fifth,
            gr.update(value="Unable to load instruction."),
            gr.update(value=[]),
            gr.update(value="Unable to load screenshots or annotations."),
        )


def update_third_dropdown(repo_id: str, top_level_dir: str, second_level_dir: str):
    """Update the third and fourth dropdowns when the second-level changes."""
    try:
        if not top_level_dir or not second_level_dir:
            empty_third = _dropdown_update(
                choices=[],
                value=None,
                label="Third-level folders",
                filled_info="Choose a third-level folder",
                empty_info="Select higher-level folders first",
            )
            empty_fourth = _dropdown_update(
                choices=[],
                value=None,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="Select higher-level folders first",
            )
            empty_fifth = _dropdown_update(
                choices=[],
                value=None,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="Select higher-level folders first",
            )
            instruction_update = gr.update(
                value="ℹ️ Select higher-level folders to display the instruction."
            )
            gallery_update = gr.update(value=[])
            annotation_update = gr.update(
                value="Select higher-level folders to load screenshots and annotations."
            )
            return (
                empty_third,
                empty_fourth,
                empty_fifth,
                instruction_update,
                gallery_update,
                annotation_update,
            )

        third_dirs = _get_subdirectories(
            repo_id, _build_path(top_level_dir, second_level_dir)
        )
        third_value = third_dirs[0] if third_dirs else None

        fourth_dirs = (
            _get_subdirectories(
                repo_id, _build_path(top_level_dir, second_level_dir, third_value)
            )
            if third_value
            else []
        )
        fourth_value = fourth_dirs[0] if fourth_dirs else None

        fifth_dirs = (
            _get_subdirectories(
                repo_id,
                _build_path(top_level_dir, second_level_dir, third_value, fourth_value),
            )
            if fourth_value
            else []
        )
        fifth_value = fifth_dirs[0] if fifth_dirs else None

        target_directory = (
            _build_path(
                top_level_dir,
                second_level_dir,
                third_value,
                fourth_value,
                fifth_value,
            )
            if fifth_value
            else None
        )
        (
            gallery_items,
            gallery_status,
            instruction_markdown,
        ) = _prepare_gallery_items(repo_id, target_directory)

        return (
            _dropdown_update(
                choices=third_dirs,
                value=third_value,
                label="Third-level folders",
                filled_info="Choose a third-level folder",
                empty_info="No third-level folders under the selection",
            ),
            _dropdown_update(
                choices=fourth_dirs,
                value=fourth_value,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="No fourth-level folders under the selection",
            ),
            _dropdown_update(
                choices=fifth_dirs,
                value=fifth_value,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="No fifth-level folders under the selection",
            ),
            gr.update(value=instruction_markdown),
            gr.update(value=gallery_items),
            gr.update(value="\n".join(gallery_status)),
        )
    except Exception as error:
        print(
            f"[update_third_dropdown] Error for {repo_id}/{top_level_dir}/{second_level_dir}: {error}",
            flush=True,
        )
        print(traceback.format_exc(), flush=True)
        empty_third = _dropdown_update(
            choices=[],
            value=None,
            label="Third-level folders",
            filled_info="Choose a third-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_fourth = _dropdown_update(
            choices=[],
            value=None,
            label="Fourth-level folders",
            filled_info="Choose a fourth-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_fifth = _dropdown_update(
            choices=[],
            value=None,
            label="Fifth-level folders",
            filled_info="Choose a fifth-level folder",
            empty_info="Unable to load subdirectories",
        )
        return (
            empty_third,
            empty_fourth,
            empty_fifth,
            gr.update(value="Unable to load instruction."),
            gr.update(value=[]),
            gr.update(value="Unable to load screenshots or annotations."),
        )


def update_fourth_dropdown(
    repo_id: str,
    top_level_dir: str,
    second_level_dir: str,
    third_level_dir: str,
):
    """Update the fourth and fifth dropdowns when the third-level changes."""
    try:
        if not top_level_dir or not second_level_dir or not third_level_dir:
            empty_fourth = _dropdown_update(
                choices=[],
                value=None,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="Select higher-level folders first",
            )
            empty_fifth = _dropdown_update(
                choices=[],
                value=None,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="Select higher-level folders first",
            )
            instruction_update = gr.update(
                value="ℹ️ Select higher-level folders to display the instruction."
            )
            gallery_update = gr.update(value=[])
            annotation_update = gr.update(
                value="Select higher-level folders to load screenshots and annotations."
            )
            return (
                empty_fourth,
                empty_fifth,
                instruction_update,
                gallery_update,
                annotation_update,
            )

        fourth_dirs = _get_subdirectories(
            repo_id,
            _build_path(top_level_dir, second_level_dir, third_level_dir),
        )
        fourth_value = fourth_dirs[0] if fourth_dirs else None

        fifth_dirs = (
            _get_subdirectories(
                repo_id,
                _build_path(
                    top_level_dir, second_level_dir, third_level_dir, fourth_value
                ),
            )
            if fourth_value
            else []
        )
        fifth_value = fifth_dirs[0] if fifth_dirs else None

        target_directory = (
            _build_path(
                top_level_dir,
                second_level_dir,
                third_level_dir,
                fourth_value,
                fifth_value,
            )
            if fifth_value
            else None
        )
        (
            gallery_items,
            gallery_status,
            instruction_markdown,
        ) = _prepare_gallery_items(repo_id, target_directory)

        return (
            _dropdown_update(
                choices=fourth_dirs,
                value=fourth_value,
                label="Fourth-level folders",
                filled_info="Choose a fourth-level folder",
                empty_info="No fourth-level folders under the selection",
            ),
            _dropdown_update(
                choices=fifth_dirs,
                value=fifth_value,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="No fifth-level folders under the selection",
            ),
            gr.update(value=instruction_markdown),
            gr.update(value=gallery_items),
            gr.update(value="\n".join(gallery_status)),
        )
    except Exception as error:
        print(
            "[update_fourth_dropdown] Error for "
            f"{repo_id}/{top_level_dir}/{second_level_dir}/{third_level_dir}: {error}",
            flush=True,
        )
        print(traceback.format_exc(), flush=True)
        empty_fourth = _dropdown_update(
            choices=[],
            value=None,
            label="Fourth-level folders",
            filled_info="Choose a fourth-level folder",
            empty_info="Unable to load subdirectories",
        )
        empty_fifth = _dropdown_update(
            choices=[],
            value=None,
            label="Fifth-level folders",
            filled_info="Choose a fifth-level folder",
            empty_info="Unable to load subdirectories",
        )
        return (
            empty_fourth,
            empty_fifth,
            gr.update(value="Unable to load instruction."),
            gr.update(value=[]),
            gr.update(value="Unable to load screenshots or annotations."),
        )


def update_fifth_dropdown(
    repo_id: str,
    top_level_dir: str,
    second_level_dir: str,
    third_level_dir: str,
    fourth_level_dir: str,
):
    """Update the fifth dropdown and gallery when the fourth-level changes."""
    try:
        if not all(
            [top_level_dir, second_level_dir, third_level_dir, fourth_level_dir]
        ):
            empty_fifth = _dropdown_update(
                choices=[],
                value=None,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="Select higher-level folders first",
            )
            instruction_update = gr.update(
                value="ℹ️ Select higher-level folders to display the instruction."
            )
            gallery_update = gr.update(value=[])
            annotation_update = gr.update(
                value="Select higher-level folders to load screenshots and annotations."
            )
            return empty_fifth, instruction_update, gallery_update, annotation_update

        fifth_dirs = _get_subdirectories(
            repo_id,
            _build_path(
                top_level_dir,
                second_level_dir,
                third_level_dir,
                fourth_level_dir,
            ),
        )
        fifth_value = fifth_dirs[0] if fifth_dirs else None

        target_directory = (
            _build_path(
                top_level_dir,
                second_level_dir,
                third_level_dir,
                fourth_level_dir,
                fifth_value,
            )
            if fifth_value
            else None
        )
        (
            gallery_items,
            gallery_status,
            instruction_markdown,
        ) = _prepare_gallery_items(repo_id, target_directory)

        return (
            _dropdown_update(
                choices=fifth_dirs,
                value=fifth_value,
                label="Fifth-level folders",
                filled_info="Choose a fifth-level folder",
                empty_info="No fifth-level folders under the selection",
            ),
            gr.update(value=instruction_markdown),
            gr.update(value=gallery_items),
            gr.update(value="\n".join(gallery_status)),
        )
    except Exception as error:
        print(
            "[update_fifth_dropdown] Error for "
            f"{repo_id}/{top_level_dir}/{second_level_dir}/{third_level_dir}/{fourth_level_dir}: {error}",
            flush=True,
        )
        print(traceback.format_exc(), flush=True)
        empty_fifth = _dropdown_update(
            choices=[],
            value=None,
            label="Fifth-level folders",
            filled_info="Choose a fifth-level folder",
            empty_info="Unable to load subdirectories",
        )
        return (
            empty_fifth,
            gr.update(value="Unable to load instruction."),
            gr.update(value=[]),
            gr.update(value="Unable to load screenshots or annotations."),
        )


def update_gallery(
    repo_id: str,
    top_level_dir: str,
    second_level_dir: str,
    third_level_dir: str,
    fourth_level_dir: str,
    fifth_level_dir: str,
):
    """Update the image gallery when the fifth-level selection changes."""
    try:
        directory = (
            _build_path(
                top_level_dir,
                second_level_dir,
                third_level_dir,
                fourth_level_dir,
                fifth_level_dir,
            )
            if all(
                [
                    top_level_dir,
                    second_level_dir,
                    third_level_dir,
                    fourth_level_dir,
                    fifth_level_dir,
                ]
            )
            else None
        )
        (
            gallery_items,
            gallery_status,
            instruction_markdown,
        ) = _prepare_gallery_items(repo_id, directory)
        return (
            gr.update(value=instruction_markdown),
            gr.update(value=gallery_items),
            gr.update(value="\n".join(gallery_status)),
        )
    except Exception as error:
        print(
            "[update_gallery] Error for "
            f"{repo_id}/{top_level_dir}/{second_level_dir}/{third_level_dir}/{fourth_level_dir}/{fifth_level_dir}: {error}",
            flush=True,
        )
        print(traceback.format_exc(), flush=True)
        return (
            gr.update(value="Unable to load instruction."),
            gr.update(value=[]),
            gr.update(value="Unable to load screenshots or annotations."),
        )


with gr.Blocks(title="HF Dataset Explorer") as demo:
    gr.Markdown(
        """# Hugging Face Dataset Explorer

Provide a dataset repository ID (e.g. `org/dataset`) to list its top-level folders."""
    )

    with gr.Row():
        repo_id_input = gr.Textbox(
            value=DEFAULT_REPO_ID,
            label="Dataset repo ID",
            placeholder="owner/dataset",
            info="Any public dataset on the Hugging Face Hub"
        )
        reload_button = gr.Button("Load repo", variant="primary")

    status_display = gr.Markdown()
    folder_dropdown = gr.Dropdown(label="Top-level folders", interactive=False)
    second_level_dropdown = gr.Dropdown(label="Second-level folders", interactive=False)
    third_level_dropdown = gr.Dropdown(label="Third-level folders", interactive=False)
    fourth_level_dropdown = gr.Dropdown(label="Fourth-level folders", interactive=False)
    fifth_level_dropdown = gr.Dropdown(label="Fifth-level folders", interactive=False)
    instruction_display = gr.Markdown()
    image_gallery = gr.Gallery(label="Images", columns=4)
    annotation_status = gr.Markdown()

    reload_button.click(
        refresh_repo,
        inputs=repo_id_input,
        outputs=[
            folder_dropdown,
            second_level_dropdown,
            third_level_dropdown,
            fourth_level_dropdown,
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
            status_display,
        ],
    )

    folder_dropdown.change(
        update_second_dropdown,
        inputs=[repo_id_input, folder_dropdown],
        outputs=[
            second_level_dropdown,
            third_level_dropdown,
            fourth_level_dropdown,
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
        ],
    )

    second_level_dropdown.change(
        update_third_dropdown,
        inputs=[repo_id_input, folder_dropdown, second_level_dropdown],
        outputs=[
            third_level_dropdown,
            fourth_level_dropdown,
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
        ],
    )

    third_level_dropdown.change(
        update_fourth_dropdown,
        inputs=[
            repo_id_input,
            folder_dropdown,
            second_level_dropdown,
            third_level_dropdown,
        ],
        outputs=[
            fourth_level_dropdown,
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
        ],
    )

    fourth_level_dropdown.change(
        update_fifth_dropdown,
        inputs=[
            repo_id_input,
            folder_dropdown,
            second_level_dropdown,
            third_level_dropdown,
            fourth_level_dropdown,
        ],
        outputs=[
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
        ],
    )

    fifth_level_dropdown.change(
        update_gallery,
        inputs=[
            repo_id_input,
            folder_dropdown,
            second_level_dropdown,
            third_level_dropdown,
            fourth_level_dropdown,
            fifth_level_dropdown,
        ],
        outputs=[instruction_display, image_gallery, annotation_status],
    )

    demo.load(
        refresh_repo,
        inputs=repo_id_input,
        outputs=[
            folder_dropdown,
            second_level_dropdown,
            third_level_dropdown,
            fourth_level_dropdown,
            fifth_level_dropdown,
            instruction_display,
            image_gallery,
            annotation_status,
            status_display,
        ],
    )

if __name__ == "__main__":
    demo.launch()