"""Image listing for the images router."""
from __future__ import annotations

from docker_client import DockerError, get_client, safe_call
from services import update_service

COMPOSE_PROJECT_LABEL = "com.docker.compose.project"


def list_images() -> list[dict]:
    """Return one row per image tag, annotated with using-stacks + update status."""
    try:
        client = get_client()
        images = safe_call(client.images.list)
        containers = safe_call(client.containers.list, all=True)
    except DockerError:
        return []

    # Map image ref -> stacks using it.
    usage: dict[str, set[str]] = {}
    for c in containers:
        ref = c.attrs.get("Config", {}).get("Image")
        stack = c.labels.get(COMPOSE_PROJECT_LABEL)
        if ref:
            usage.setdefault(ref, set())
            if stack:
                usage[ref].add(stack)

    cache = update_service.get_cache()
    result = []
    for img in images:
        tags = img.tags or []
        if not tags:
            continue
        for tag in tags:
            result.append(
                {
                    "id": img.short_id,
                    "tag": tag,
                    "size": img.attrs.get("Size", 0),
                    "created": img.attrs.get("Created"),
                    "stacks": sorted(usage.get(tag, set())),
                    "update": cache.get(tag),
                }
            )
    result.sort(key=lambda r: r["tag"])
    return result


def prune_images(all_unused: bool = False) -> dict:
    """Remove unused images. By default only dangling (untagged) images are
    removed; ``all_unused=True`` removes every image not referenced by a
    container (``docker image prune -a``)."""
    client = get_client()
    # dangling=false tells the engine to also consider tagged-but-unused images.
    filters = {"dangling": False} if all_unused else {"dangling": True}
    result = safe_call(client.images.prune, filters=filters)
    return {
        "ImagesDeleted": result.get("ImagesDeleted") or [],
        "SpaceReclaimed": result.get("SpaceReclaimed", 0),
    }