import os
import time
import uuid

import pytest
from PySide6.QtCore import QCoreApplication

from mtga_assistant.background import (
    LaunchWatcher,
    SingleInstance,
    autostart_enabled,
    desktop_exec,
    launch_command,
    set_autostart,
)


@pytest.fixture(scope="module")
def app():
    return QCoreApplication.instance() or QCoreApplication([])


def wait_for(app, cond, timeout=3.0):
    end = time.monotonic() + timeout
    while time.monotonic() < end:
        app.processEvents()
        if cond():
            return True
        time.sleep(0.01)
    app.processEvents()
    return cond()


def test_second_launch_messages_the_running_instance(app):
    name = f"mtga-assistant-test-{uuid.uuid4().hex[:8]}"
    first = SingleInstance(name)
    assert not first.send("show")  # nobody running yet
    assert first.listen()
    got = []
    first.message.connect(got.append)

    second = SingleInstance(name)
    try:
        assert second.send("show")
        assert wait_for(app, lambda: got == ["show"])
    finally:
        # Let queued socket events run before the objects go away.
        first.close()
        wait_for(app, lambda: False, timeout=0.2)


def test_launch_watcher_reports_new_log_not_appends(app, tmp_path):
    log = tmp_path / "Player.log"
    log.write_text("old session\n")
    watcher = LaunchWatcher(log)
    assert watcher.active
    launches = []
    watcher.launched.connect(lambda: launches.append(1))

    # Normal logging: no launch.
    with open(log, "a") as f:
        f.write("more\n")
    wait_for(app, lambda: False, timeout=0.3)
    assert launches == []

    # MTGA starts: old log becomes Player-prev.log, a new Player.log appears.
    os.replace(log, tmp_path / "Player-prev.log")
    log.write_text("new session\n")
    assert wait_for(app, lambda: len(launches) >= 1)

    # Still watching the new file: a truncate-in-place restart is reported too.
    count = len(launches)
    with open(log, "a") as f:
        f.write("lots of lines\n" * 50)
    wait_for(app, lambda: False, timeout=0.3)
    assert len(launches) == count
    log.write_text("")
    assert wait_for(app, lambda: len(launches) > count)


def test_launch_watcher_without_folder_is_inactive(app, tmp_path):
    assert not LaunchWatcher(tmp_path / "missing" / "Player.log").active


def test_linux_autostart_entry(monkeypatch, tmp_path):
    monkeypatch.setenv("XDG_CONFIG_HOME", str(tmp_path))
    assert not autostart_enabled("linux")
    set_autostart(True, "linux")
    entry = tmp_path / "autostart" / "mtga-assistant.desktop"
    text = entry.read_text()
    assert autostart_enabled("linux")
    assert "--background" in text and "Exec=" in text
    set_autostart(False, "linux")
    assert not entry.exists() and not autostart_enabled("linux")


def test_launch_command_starts_hidden():
    cmd = launch_command()
    assert cmd[-1] == "--background"


def test_desktop_exec_quoting():
    assert desktop_exec(["/usr/bin/python", "-m", "x"]) == "/usr/bin/python -m x"
    assert desktop_exec(["/a b/c"]) == '"/a b/c"'
    assert desktop_exec(['/a"b']) == '"/a\\"b"'