import os
import time
from pathlib import Path

from leann.embedding_server_manager import EmbeddingServerManager


def _configure_fake_module_env(monkeypatch):
    root = Path(__file__).resolve().parents[1]
    support_path = str(root / "tests" / "support")
    existing = os.environ.get("PYTHONPATH", "")
    joined = support_path if not existing else f"{support_path}{os.pathsep}{existing}"
    monkeypatch.setenv("PYTHONPATH", joined)


def _wait_until(predicate, timeout=5.0, interval=0.05):
    deadline = time.time() + timeout
    while time.time() < deadline:
        if predicate():
            return True
        time.sleep(interval)
    return False


def test_daemon_reuse_with_real_subprocess(tmp_path, monkeypatch):
    _configure_fake_module_env(monkeypatch)
    monkeypatch.setattr(
        EmbeddingServerManager, "_registry_dir", staticmethod(lambda: tmp_path / "servers")
    )

    manager1 = EmbeddingServerManager("fake_embedding_server_module")
    ok1, port1 = manager1.start_server(
        port=6151,
        model_name="fake-model",
        use_daemon=True,
        daemon_ttl_seconds=60,
        enable_warmup=True,
    )
    assert ok1 and port1 == 6151
    assert manager1.server_process is not None
    pid1 = manager1.server_process.pid

    manager2 = EmbeddingServerManager("fake_embedding_server_module")
    ok2, port2 = manager2.start_server(
        port=6151,
        model_name="fake-model",
        use_daemon=True,
        daemon_ttl_seconds=60,
    )
    assert ok2 and port2 == 6151
    # Adoption path: no newly spawned process object attached.
    assert manager2.server_process is None

    records = EmbeddingServerManager.list_daemons()
    assert len(records) == 1
    assert int(records[0]["pid"]) == pid1

    stopped = EmbeddingServerManager.stop_daemons(
        backend_module_name="fake_embedding_server_module"
    )
    assert stopped == 1


def test_daemon_ttl_expiry_with_real_subprocess(tmp_path, monkeypatch):
    _configure_fake_module_env(monkeypatch)
    monkeypatch.setattr(
        EmbeddingServerManager, "_registry_dir", staticmethod(lambda: tmp_path / "servers")
    )

    manager = EmbeddingServerManager("fake_embedding_server_module")
    ok, port = manager.start_server(
        port=6152,
        model_name="fake-model",
        use_daemon=True,
        daemon_ttl_seconds=1,
        enable_warmup=False,
    )
    assert ok and port == 6152

    # Fake daemon should self-exit after idle TTL.
    expired = _wait_until(lambda: len(EmbeddingServerManager.list_daemons()) == 0, timeout=4.0)
    assert expired