"""Recover the pinned Tomie build's media and ResourceManager actor bindings."""
import hashlib
from pathlib import Path

from app.blobs import put_file
from app.converter import assets
from app.converter.compatibility import CompatibilityError, Issue


def recover_object(obj, data: Path, out: Path, stem: str):
    """Decode a single owned temporary file; never rename or edit a source file."""
    asset = obj.read()
    kind, size = obj.type.name, None
    if kind == "Texture2D":
        if asset.m_Width == 0 or asset.m_Height == 0:
            return None  # empty runtime font atlas
        path = out / (stem + ".png")
        asset.image.save(path, compress_level=1)
        size = [asset.m_Width, asset.m_Height]
    elif kind == "AudioClip":
        samples = asset.samples
        if len(samples) != 1:
            raise ValueError("Не найден единственный аудиоклип")
        filename, raw = next(iter(samples.items()))
        extension = Path(filename).suffix.lower() or ".wav"
        if extension not in assets.AUDIO_EXTS:
            raise ValueError("Не поддерживается контейнер аудиоклипа " + extension)
        path = out / (stem + extension)
        path.write_bytes(raw)
    elif kind == "Font":
        raw = bytes(asset.m_FontData or b"")
        if not raw:
            return None
        path = out / (stem + (".otf" if raw[:4] == b"OTTO" else ".ttf"))
        path.write_bytes(raw)
    elif kind == "VideoClip":
        tree = obj.read_typetree()
        reference = tree["m_ExternalResources"]
        source_name = reference["m_Source"].replace("\\", "/").rsplit("/", 1)[-1]
        resource = data / source_name
        offset, length = int(reference["m_Offset"]), int(reference["m_Size"])
        if not resource.is_file() or offset < 0 or length <= 0 or offset + length > resource.stat().st_size:
            raise ValueError("Некорректный диапазон исходного видео")
        extension = Path(tree["m_OriginalPath"]).suffix.lower()
        if extension not in assets.VIDEO_EXTS:
            raise ValueError("Не поддерживается исходный видеоконтейнер " + extension)
        path = out / (stem + extension)
        with resource.open("rb") as incoming, path.open("wb") as outgoing:
            incoming.seek(offset)
            remaining = length
            while remaining:
                chunk = incoming.read(min(1 << 20, remaining))
                if not chunk:
                    raise EOFError("Оборванный видеопоток")
                outgoing.write(chunk)
                remaining -= len(chunk)
    else:
        raise ValueError("Не поддерживается тип медиа " + kind)
    return {"path": path, "name": asset.m_Name.lower(), "size": size,
            "kind": {"Texture2D": "image", "AudioClip": "audio", "Font": "font", "VideoClip": "video"}[kind]}


def export_media(package, root: Path, work: Path, progress):
    if package.issues:
        raise CompatibilityError("naninovel", package.issues)
    data = root / "TomieWGM_Data"
    out = work / "media"
    out.mkdir(parents=True, exist_ok=True)
    files, counts = {}, {"image": 0, "audio": 0, "video": 0, "font": 0}
    index = {"backgrounds": {}, "characters": {}, "audio": {}, "videos": {}, "textures": {}, "fonts": {}}
    exported = {}

    def store(path: Path, kind: str):
        converted, extension = assets.convert(path, out)
        digest, size = put_file(converted, extension, move=True)
        logical = "media/" + digest
        files[logical] = {"hash": digest, "size": size}
        counts[kind] += 1
        return logical

    for number, source in enumerate(sorted((data / "Resources/Backgrounds/MainBackground").rglob("*"))):
        if not source.is_file():
            continue
        if assets.kind_of(source) != "image":
            raise CompatibilityError("naninovel", [Issue("unsupported_background", "Не поддерживается формат фона Tomie", source.name)])
        if number % 100 == 0:
            progress(f"Фоны Tomie: {number}")
        name = source.stem.lower()
        if name in index["backgrounds"]:
            raise CompatibilityError("naninovel", [Issue("ambiguous_background", "Неоднозначный фон Tomie", name)])
        index["backgrounds"][name] = store(source, "image")

    objects = {}
    for source, obj in package.resources:
        identity = f"{source.relative_to(root).as_posix()}:{obj.assets_file.name}:{obj.path_id}"
        objects.setdefault(identity, (source, obj))
    for number, (identity, (source, obj)) in enumerate(objects.items()):
        if number % 100 == 0:
            progress(f"Ресурсы Tomie: {number}/{len(objects)}")
        try:
            stem = hashlib.sha256(identity.encode()).hexdigest()[:24]
            recovered = recover_object(obj, data, out, stem)
            if recovered is None:
                continue
            path, name = recovered["path"], recovered["name"]
            try:
                logical = store(path, recovered["kind"])
            finally:
                path.unlink(missing_ok=True)
            if obj.type.name == "Texture2D":
                exported[identity] = {"file": logical, "size": recovered["size"]}
                # Main resources take precedence over the UI bundle, as in the port.
                index["textures"].setdefault(name, logical)
            elif obj.type.name == "AudioClip":
                index["audio"].setdefault(name, logical)
            elif obj.type.name == "Font":
                index["fonts"].setdefault(name, logical)
            elif obj.type.name == "VideoClip":
                index["videos"][name] = logical
        except Exception as exc:
            raise CompatibilityError("naninovel", [Issue("tomie_media", f"Не удалось восстановить медиа: {exc}", identity)]) from exc
    for name, identity in package.actor_resources.items():
        if identity not in exported:
            raise CompatibilityError("naninovel", [Issue("missing_actor", "Не найдено исходное изображение персонажа", name)])
        index["characters"][name] = exported[identity]
    if not index["backgrounds"] or not index["characters"] or not index["videos"]:
        raise CompatibilityError("naninovel", [Issue("missing_media", "Не восстановлены все категории медиа Tomie")])
    return files, index, counts