from pathlib import Path
from subprocess import CalledProcessError
from types import SimpleNamespace

import pytest

from hermes_cli import main as hermes_main


def test_stash_local_changes_if_needed_returns_none_when_tree_clean(monkeypatch, tmp_path):
    calls = []

    def fake_run(cmd, **kwargs):
        calls.append((cmd, kwargs))
        if cmd[-2:] == ["status", "--porcelain"]:
            return SimpleNamespace(stdout="", returncode=0)
        raise AssertionError(f"unexpected command: {cmd}")

    monkeypatch.setattr(hermes_main.subprocess, "run", fake_run)

    stash_ref = hermes_main._stash_local_changes_if_needed(["git"], tmp_path)

    assert stash_ref is None
    assert [cmd[-2:] for cmd, _ in calls] == [["status", "--porcelain"]]


def test_stash_local_changes_if_needed_returns_specific_stash_commit(monkeypatch, tmp_path):
    calls = []

    def fake_run(cmd, **kwargs):
        calls.append((cmd, kwargs))
        if cmd[-2:] == ["status", "--porcelain"]:
            return SimpleNamespace(stdout=" M hermes_cli/main.py\n?? notes.txt\n", returncode=0)
        if cmd[1:4] == ["stash", "push", "--include-untracked"]:
            return SimpleNamespace(stdout="Saved working directory\n", returncode=0)
        if cmd[-3:] == ["rev-parse", "--verify", "refs/stash"]:
            return SimpleNamespace(stdout="abc123\n", returncode=0)
        raise AssertionError(f"unexpected command: {cmd}")

    monkeypatch.setattr(hermes_main.subprocess, "run", fake_run)

    stash_ref = hermes_main._stash_local_changes_if_needed(["git"], tmp_path)

    assert stash_ref == "abc123"
    assert calls[1][0][1:4] == ["stash", "push", "--include-untracked"]
    assert calls[2][0][-3:] == ["rev-parse", "--verify", "refs/stash"]


def test_restore_stashed_changes_applies_specific_stash_and_drops_it(monkeypatch, tmp_path, capsys):
    calls = []

    def fake_run(cmd, **kwargs):
        calls.append((cmd, kwargs))
        if cmd[1:3] == ["stash", "apply"]:
            return SimpleNamespace(stdout="applied\n", stderr="", returncode=0)
        if cmd[1:3] == ["stash", "drop"]:
            return SimpleNamespace(stdout="dropped\n", stderr="", returncode=0)
        raise AssertionError(f"unexpected command: {cmd}")

    monkeypatch.setattr(hermes_main.subprocess, "run", fake_run)

    hermes_main._restore_stashed_changes(["git"], tmp_path, "abc123")

    assert calls[0][0] == ["git", "stash", "apply", "abc123"]
    assert calls[1][0] == ["git", "stash", "drop", "abc123"]
    assert "Restoring local changes" in capsys.readouterr().out


def test_restore_stashed_changes_exits_cleanly_when_apply_fails(monkeypatch, tmp_path, capsys):
    calls = []

    def fake_run(cmd, **kwargs):
        calls.append((cmd, kwargs))
        if cmd[1:3] == ["stash", "apply"]:
            return SimpleNamespace(stdout="conflict output\n", stderr="conflict stderr\n", returncode=1)
        raise AssertionError(f"unexpected command: {cmd}")

    monkeypatch.setattr(hermes_main.subprocess, "run", fake_run)

    with pytest.raises(SystemExit, match="1"):
        hermes_main._restore_stashed_changes(["git"], tmp_path, "abc123")

    out = capsys.readouterr().out
    assert "Your changes are still preserved in git stash." in out
    assert "git stash apply abc123" in out
    assert calls == [(["git", "stash", "apply", "abc123"], {"cwd": tmp_path, "capture_output": True, "text": True})]


def test_stash_local_changes_if_needed_raises_when_stash_ref_missing(monkeypatch, tmp_path):
    def fake_run(cmd, **kwargs):
        if cmd[-2:] == ["status", "--porcelain"]:
            return SimpleNamespace(stdout=" M hermes_cli/main.py\n", returncode=0)
        if cmd[1:4] == ["stash", "push", "--include-untracked"]:
            return SimpleNamespace(stdout="Saved working directory\n", returncode=0)
        if cmd[-3:] == ["rev-parse", "--verify", "refs/stash"]:
            raise CalledProcessError(returncode=128, cmd=cmd)
        raise AssertionError(f"unexpected command: {cmd}")

    monkeypatch.setattr(hermes_main.subprocess, "run", fake_run)

    with pytest.raises(CalledProcessError):
        hermes_main._stash_local_changes_if_needed(["git"], Path(tmp_path))