"""Round 19: version display + git self-update (updater, version button)."""

import subprocess

import pytest
from PyQt6.QtCore import QObject, pyqtSignal

from lintunes import __version__
from lintunes.updater import Updater


class FakeCompleted:
    def __init__(self, returncode=0, stdout="", stderr=""):
        self.returncode = returncode
        self.stdout = stdout
        self.stderr = stderr


def make_updater(monkeypatch, git_responses):
    """An Updater whose git calls are served from `git_responses`:
    {subcommand: FakeCompleted or Exception}. Unlisted subcommands succeed
    with empty output."""

    def fake_run(cmd, **kwargs):
        assert cmd[0] == "git" and cmd[1] == "-C"
        sub = cmd[3]
        response = git_responses.get(sub, FakeCompleted())
        if isinstance(response, Exception):
            raise response
        return response

    monkeypatch.setattr(subprocess, "run", fake_run)
    return Updater()


def collect(signal):
    got = []
    signal.connect(lambda *args: got.append(args[0] if args else None))
    return got


def test_updater_disabled_outside_git_checkout(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {
        "rev-parse": FakeCompleted(returncode=128, stderr="not a git repo")})
    assert not updater.enabled
    # disabled updater never spawns work
    updater.check_async()
    updater.update_async()


def test_check_emits_update_available(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {
        "rev-parse": FakeCompleted(stdout="/repo\n"),
        "rev-list": FakeCompleted(stdout="3\n"),
    })
    assert updater.enabled
    got = collect(updater.update_available)
    updater._check()  # run synchronously; check_async just threads this
    assert got == [3]


def test_check_quiet_when_up_to_date(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {
        "rev-list": FakeCompleted(stdout="0\n")})
    got = collect(updater.update_available)
    updater._check()
    assert got == []


def test_check_quiet_when_fetch_fails(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {
        "fetch": FakeCompleted(returncode=128, stderr="ssh: no route to host"),
        "rev-list": FakeCompleted(stdout="3\n"),
    })
    got = collect(updater.update_available)
    updater._check()
    assert got == []  # offline is normal — no signal, no error


def test_update_applied_on_clean_pull(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {"pull": FakeCompleted(returncode=0)})
    applied = collect(updater.update_applied)
    failed = collect(updater.update_failed)
    updater._update()
    assert len(applied) == 1
    assert failed == []


def test_update_failed_surfaces_git_error(qapp, monkeypatch):
    # The message is the error:/fatal: line, not git's trailing "Aborting"
    updater = make_updater(monkeypatch, {
        "pull": FakeCompleted(returncode=1,
                              stderr="error: Your local changes to the "
                                     "following files would be overwritten "
                                     "by merge:\n\ttasks-done.md\n"
                                     "Aborting")})
    applied = collect(updater.update_applied)
    failed = collect(updater.update_failed)
    updater._update()
    assert applied == []
    assert failed == ["error: Your local changes to the following files "
                      "would be overwritten by merge:"]


def test_short_hash(qapp, monkeypatch):
    updater = make_updater(monkeypatch, {
        "rev-parse": FakeCompleted(stdout="abc1234\n")})
    assert updater.short_hash() == "abc1234"


# ---- version button ----

class FakeUpdater(QObject):  # QObject with the Updater's signal surface
    update_available = pyqtSignal(int)
    update_applied = pyqtSignal()
    update_failed = pyqtSignal(str)

    def __init__(self):
        super().__init__()
        self.enabled = True
        self.update_calls = 0

    def short_hash(self):
        return "abc1234"

    def update_async(self):
        self.update_calls += 1


@pytest.fixture
def button(qapp):
    from lintunes.gui.version_button import VersionButton
    fake = FakeUpdater()
    return VersionButton(fake), fake


def test_button_shows_version_and_hash(button):
    btn, fake = button
    assert btn.text() == f"v{__version__}"
    assert "abc1234" in btn.toolTip()


def test_button_star_on_update_available(button):
    btn, fake = button
    fake.update_available.emit(2)
    assert btn.text() == f"v{__version__}*"
    assert "click to update" in btn.toolTip()


def test_click_without_update_does_nothing(button):
    btn, fake = button
    btn._on_clicked()
    assert fake.update_calls == 0


def test_click_with_update_confirms_then_pulls(button, monkeypatch):
    btn, fake = button
    fake.update_available.emit(1)
    monkeypatch.setattr(btn, "_confirm", lambda: True)
    btn._on_clicked()
    assert fake.update_calls == 1
    assert btn.text() == "updating…"
    assert not btn.isEnabled()


def test_click_with_update_declined(button, monkeypatch):
    btn, fake = button
    fake.update_available.emit(1)
    monkeypatch.setattr(btn, "_confirm", lambda: False)
    btn._on_clicked()
    assert fake.update_calls == 0
    assert btn.isEnabled()


def test_failed_update_reenables_button(button, monkeypatch):
    btn, fake = button
    fake.update_available.emit(1)
    monkeypatch.setattr(btn, "_confirm", lambda: True)
    btn._on_clicked()
    messages = collect(btn.status_message)
    fake.update_failed.emit("fatal: no route to host")
    assert btn.isEnabled()
    assert btn.text() == f"v{__version__}*"
    assert messages == ["Update failed: fatal: no route to host"]


def test_version_matches_setup_py():
    import re
    from pathlib import Path
    setup_py = Path(__file__).parents[1] / "setup.py"
    # setup.py reads the version from lintunes/__init__.py textually
    assert "__init__.py" in setup_py.read_text()
    init = Path(__file__).parents[1] / "lintunes" / "__init__.py"
    found = re.search(r'^__version__ = "([^"]+)"', init.read_text(), re.M)
    assert found and found[1] == __version__