"""Docker network management."""
from __future__ import annotations

from typing import Optional

from docker.errors import APIError
from docker.types import IPAMConfig, IPAMPool

from docker_client import DockerError, get_client, safe_call

COMPOSE_PROJECT_LABEL = "com.docker.compose.project"
DEFAULT_NETWORKS = {"bridge", "host", "none"}


def _summary(net) -> dict:
    attrs = net.attrs
    ipam = (attrs.get("IPAM") or {}).get("Config") or []
    subnet = ipam[0].get("Subnet") if ipam else None
    gateway = ipam[0].get("Gateway") if ipam else None
    containers = attrs.get("Containers") or {}
    names = [c.get("Name", cid[:12]) for cid, c in containers.items()]
    labels = attrs.get("Labels") or {}
    name = attrs.get("Name", net.name)
    return {
        "id": net.id[:12],
        "name": name,
        "driver": attrs.get("Driver"),
        "scope": attrs.get("Scope"),
        "internal": attrs.get("Internal", False),
        "attachable": attrs.get("Attachable", False),
        "subnet": subnet,
        "gateway": gateway,
        "containers": names,
        "in_use": bool(names),
        "stack": labels.get(COMPOSE_PROJECT_LABEL),
        "labels": labels,
        "created": attrs.get("Created"),
        "is_default": name in DEFAULT_NETWORKS,
    }


def list_networks() -> list[dict]:
    client = get_client()
    nets = safe_call(client.networks.list)
    # list() entries are lightweight; reload for Containers/IPAM detail.
    out = []
    for n in nets:
        try:
            n.reload()
        except APIError:
            pass
        out.append(_summary(n))
    return sorted(out, key=lambda x: (x["is_default"] is False, x["name"]))


def inspect_network(network_id: str) -> dict:
    client = get_client()
    net = safe_call(client.networks.get, network_id)
    return _summary(net)


def create_network(spec: dict) -> dict:
    name = (spec.get("name") or "").strip()
    if not name:
        raise DockerError("invalid_request", "Network name is required")
    driver = spec.get("driver") or "bridge"
    ipam = None
    subnet = (spec.get("subnet") or "").strip()
    gateway = (spec.get("gateway") or "").strip()
    if subnet:
        pool = IPAMPool(subnet=subnet, gateway=gateway or None)
        ipam = IPAMConfig(pool_configs=[pool])

    client = get_client()
    net = safe_call(
        client.networks.create,
        name=name,
        driver=driver,
        internal=bool(spec.get("internal")),
        attachable=bool(spec.get("attachable", True)),
        ipam=ipam,
        options=spec.get("options") or None,
        labels=spec.get("labels") or None,
    )
    net.reload()
    return _summary(net)


def delete_network(network_id: str) -> None:
    client = get_client()
    net = safe_call(client.networks.get, network_id)
    name = (net.attrs or {}).get("Name", net.name)
    if name in DEFAULT_NETWORKS:
        raise DockerError("forbidden", f"Cannot delete the default '{name}' network")
    safe_call(net.remove)


def prune_networks() -> dict:
    client = get_client()
    return safe_call(client.networks.prune)