"""End-to-end v2 rebuild: crop new sessions, rebuild parquets, regenerate
previews, refresh the README v2 gallery from previews/v2/*.png.

Replaces the manual crop -> build -> preview -> hand-edit-README loop with one
command. The README block between <!-- v2-gallery-start --> and
<!-- v2-gallery-end --> is rewritten in alphabetical session order from the
on-disk previews, so adding a session is purely a matter of cropping +
rebuilding -- the gallery follows automatically.

Usage:
    uv run python scripts/v2/compile.py
"""

from __future__ import annotations

import importlib.util
from pathlib import Path

SCRIPT_DIR = Path(__file__).resolve().parent
REPO_ROOT = SCRIPT_DIR.parents[1]
PREVIEWS_DIR = REPO_ROOT / "previews" / "v2"
README = REPO_ROOT / "README.md"
GALLERY_START = "<!-- v2-gallery-start -->"
GALLERY_END = "<!-- v2-gallery-end -->"


def _load_module(stem: str):
    """Load a sibling script whose filename starts with a digit."""
    path = SCRIPT_DIR / f"{stem}.py"
    spec = importlib.util.spec_from_file_location(stem.replace("/", "_"), path)
    mod = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(mod)
    return mod


def _refresh_readme_gallery() -> None:
    text = README.read_text()
    if GALLERY_START not in text or GALLERY_END not in text:
        raise RuntimeError(
            f"sentinel comments not found in {README}: expected "
            f"{GALLERY_START!r} and {GALLERY_END!r}"
        )
    previews = sorted(PREVIEWS_DIR.glob("*.png"))
    body = "\n\n".join(
        f"#### `{p.stem}`\n![](previews/v2/{p.name})" for p in previews
    )
    head, _, rest = text.partition(GALLERY_START)
    _, _, tail = rest.partition(GALLERY_END)
    README.write_text(f"{head}{GALLERY_START}\n\n{body}\n\n{GALLERY_END}{tail}")
    print(f"refreshed README gallery: {len(previews)} sessions")


def main() -> None:
    print("== 01 crop ==")
    _load_module("01_crop_d555").main()
    print("\n== 02 build ==")
    _load_module("02_build_dataset").main()
    print("\n== 03 previews ==")
    _load_module("03_make_previews").main()
    print("\n== readme ==")
    _refresh_readme_gallery()


if __name__ == "__main__":
    main()