from __future__ import annotations

from pathlib import Path

from relay.dispatch import DispatchManager


def test_writes_input_when_session_dir_empty(tmp_path: Path) -> None:
    mgr = DispatchManager(tmp_path / "dispatch")
    delivered = mgr.queue_or_write("session-1", "hello")
    assert delivered is True
    assert (tmp_path / "dispatch" / "session-1" / "input.txt").read_text() == "hello"


def test_does_not_overwrite_pending_input(tmp_path: Path) -> None:
    mgr = DispatchManager(tmp_path / "dispatch")
    mgr.queue_or_write("session-1", "first")
    delivered = mgr.queue_or_write("session-1", "second")
    assert delivered is False
    # First file unchanged
    assert (tmp_path / "dispatch" / "session-1" / "input.txt").read_text() == "first"
    assert mgr.has_pending("session-1")


def test_flush_all_delivers_after_consumer_deletes(tmp_path: Path) -> None:
    mgr = DispatchManager(tmp_path / "dispatch")
    mgr.queue_or_write("session-1", "first")
    mgr.queue_or_write("session-1", "second")
    # Consumer "consumes" first
    (tmp_path / "dispatch" / "session-1" / "input.txt").unlink()
    delivered = mgr.flush_all()
    assert delivered == 1
    assert (tmp_path / "dispatch" / "session-1" / "input.txt").read_text() == "second"
    assert not mgr.has_pending("session-1")


def test_independent_sessions_do_not_block_each_other(tmp_path: Path) -> None:
    mgr = DispatchManager(tmp_path / "dispatch")
    mgr.queue_or_write("session-1", "a")  # blocks on session-1
    delivered = mgr.queue_or_write("session-2", "b")  # session-2 unaffected
    assert delivered is True
    assert (tmp_path / "dispatch" / "session-2" / "input.txt").read_text() == "b"


def test_input_path_resolution(tmp_path: Path) -> None:
    mgr = DispatchManager(tmp_path / "dispatch")
    p = mgr.input_path("session-1")
    assert p == tmp_path / "dispatch" / "session-1" / "input.txt"