"""Tests for ci_orchestrator.ip_pool — IpSlotPool acquire/release."""

from __future__ import annotations

import json
from pathlib import Path

import pytest

from ci_orchestrator.ip_pool import IpSlotPool


def make_pool(tmp_path: Path, addresses: list[str] | None = None) -> IpSlotPool:
    return IpSlotPool(
        addresses=addresses or ["10.0.0.1", "10.0.0.2"],
        netmask="255.255.255.0",
        gateway="10.0.0.254",
        lease_file=tmp_path / "ip-pool.json",
    )


# ── construction ────────────────────────────────────────────────────────────


def test_empty_addresses_raises(tmp_path: Path) -> None:
    with pytest.raises(ValueError, match="at least one"):
        IpSlotPool([], "255.255.255.0", "", tmp_path / "pool.json")


# ── acquire ─────────────────────────────────────────────────────────────────


def test_acquire_returns_first_free_ip(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    ip = pool.acquire("owner-1")
    assert ip == "10.0.0.1"


def test_acquire_second_slot(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    pool.acquire("owner-1")
    ip2 = pool.acquire("owner-2")
    assert ip2 == "10.0.0.2"


def test_acquire_writes_lease_file(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    pool.acquire("owner-1")
    leases = json.loads((tmp_path / "ip-pool.json").read_text())
    assert leases["10.0.0.1"] == "owner-1"
    assert leases["10.0.0.2"] is None


def test_acquire_exhausted_raises(tmp_path: Path) -> None:
    pool = make_pool(tmp_path, addresses=["10.0.0.1"])
    pool.acquire("owner-1")
    with pytest.raises(RuntimeError, match="exhausted"):
        pool.acquire("owner-2", timeout=0)


# ── release ──────────────────────────────────────────────────────────────────


def test_release_frees_slot(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    ip = pool.acquire("owner-1")
    pool.release(ip)
    leases = json.loads((tmp_path / "ip-pool.json").read_text())
    assert leases[ip] is None


def test_release_unknown_ip_is_noop(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    pool.release("99.99.99.99")  # should not raise


def test_release_and_reacquire(tmp_path: Path) -> None:
    pool = make_pool(tmp_path, addresses=["10.0.0.1"])
    ip = pool.acquire("owner-1")
    pool.release(ip)
    ip2 = pool.acquire("owner-2")
    assert ip2 == "10.0.0.1"


# ── persistence ──────────────────────────────────────────────────────────────


def test_second_pool_instance_sees_leases(tmp_path: Path) -> None:
    lease = tmp_path / "ip-pool.json"
    p1 = IpSlotPool(["10.0.0.1", "10.0.0.2"], "255.255.255.0", "", lease)
    p1.acquire("owner-1")

    p2 = IpSlotPool(["10.0.0.1", "10.0.0.2"], "255.255.255.0", "", lease)
    ip = p2.acquire("owner-2")
    assert ip == "10.0.0.2"


def test_corrupt_lease_file_treated_as_empty(tmp_path: Path) -> None:
    lease = tmp_path / "ip-pool.json"
    lease.write_text("NOT JSON", encoding="utf-8")
    pool = make_pool(tmp_path)
    ip = pool.acquire("owner-1")
    assert ip == "10.0.0.1"


def test_missing_lease_file_treated_as_empty(tmp_path: Path) -> None:
    pool = make_pool(tmp_path)
    ip = pool.acquire("owner-1")
    assert ip == "10.0.0.1"


def test_non_dict_lease_json_treated_as_empty(tmp_path: Path) -> None:
    lease = tmp_path / "ip-pool.json"
    lease.write_text("[1, 2, 3]", encoding="utf-8")  # valid JSON but not a dict
    pool = make_pool(tmp_path)
    ip = pool.acquire("owner-1")
    assert ip == "10.0.0.1"