사진 갤러리와 전후 비교의 공개 목록을 나누는 모듈

"""Pure synthetic metadata projection, not visual review or media authorization."""
from dataclasses import dataclass


@dataclass(frozen=True)
class Photo:
    id: str
    case_id: str
    space_id: str
    room: str
    phase: str
    display_width: int
    display_height: int
    reviewed: bool = False
    held: bool = False


@dataclass(frozen=True)
class Pair:
    id: str
    before: str
    after: str
    room: str
    same_view_reviewed: bool = False
    priority: int = 10


def _ids(values):
    if any(not isinstance(v, str) or not v.strip() for v in values):
        raise ValueError('Identifiers must be nonempty strings')
    if len(set(values)) != len(values):
        raise ValueError('Duplicate identifier')


def _orientation(photo):
    return (photo.display_width > photo.display_height) - (photo.display_width < photo.display_height)


def project(*, case_id, photos, pairs, gallery_order, preferred_cover=None):
    """Project already-reviewed metadata. Never infer scene identity from pixels.

    Gallery order is an explicit editorial input. A comparison-only after image
    does not become a gallery image merely because it is used in a valid pair.
    Width/height must describe the upright displayed frame, not raw EXIF data.
    """
    if not isinstance(case_id, str) or not case_id.strip():
        raise ValueError('A target case is required')
    photos, pairs, gallery_order = tuple(photos), tuple(pairs), tuple(gallery_order)
    if not all(isinstance(p, Photo) for p in photos) or not all(isinstance(p, Pair) for p in pairs):
        raise ValueError('Expected Photo and Pair records')
    _ids([p.id for p in photos]); _ids([p.id for p in pairs]); _ids(gallery_order)
    lookup = {p.id: p for p in photos}
    if any(k not in lookup for k in gallery_order):
        raise ValueError('Gallery references a missing photo')
    for p in photos:
        if p.phase not in ('before', 'after'):
            raise ValueError('Unknown construction phase')
        if type(p.reviewed) is not bool or type(p.held) is not bool:
            raise ValueError('Review and hold flags must be booleans')
        if any(type(v) is not int or v <= 0 for v in (p.display_width, p.display_height)):
            raise ValueError('Displayed dimensions must be positive integers')
        if any(not isinstance(v, str) for v in (p.case_id, p.space_id, p.room)):
            raise ValueError('Photo context must use string identifiers')
    for p in pairs:
        if type(p.same_view_reviewed) is not bool or type(p.priority) is not int:
            raise ValueError('Invalid pair review or priority')
        if not all(isinstance(v, str) for v in (p.before, p.after, p.room)):
            raise ValueError('Invalid pair references')
    def usable(p):
        return p.reviewed and not p.held and p.case_id == case_id
    gallery = [k for k in gallery_order if usable(lookup[k]) and lookup[k].phase == 'after']
    accepted = []
    for pair in sorted(pairs, key=lambda p: (p.priority, p.id)):
        before, after = lookup.get(pair.before), lookup.get(pair.after)
        if not pair.same_view_reviewed or before is None or after is None:
            continue
        if not usable(before) or not usable(after):
            continue
        if (before.phase, after.phase) != ('before', 'after'):
            continue
        if not before.space_id or before.space_id != after.space_id:
            continue
        if not pair.room or not before.room or not (pair.room == before.room == after.room):
            continue
        if _orientation(before) != _orientation(after):
            continue
        if any(p.room == pair.room for p in accepted):
            continue
        accepted.append(pair)
    compare = list(dict.fromkeys(k for p in accepted for k in (p.before, p.after)))
    public = list(dict.fromkeys(gallery + compare))
    cover = preferred_cover if preferred_cover in gallery else next(iter(gallery), None)
    return {'case_id': case_id, 'gallery_ids': gallery, 'pair_ids': [p.id for p in accepted],
            'comparison_ids': compare, 'public_photo_ids': public, 'cover_id': cover,
            'empty_state': 'after_photos_pending' if not public else None}