import os
import subprocess
from pathlib import Path

import pytest

from python_git import GitCommandError, InvalidGitRepositoryError, Repo


def _init_repo(path: Path) -> Repo:
    subprocess.run(["git", "init", "-q", str(path)], check=True)
    subprocess.run(["git", "-C", str(path), "config", "user.email", "test@example.com"], check=True)
    subprocess.run(["git", "-C", str(path), "config", "user.name", "Test User"], check=True)
    return Repo(path)


def test_invalid_repository_raises(tmp_path):
    with pytest.raises(InvalidGitRepositoryError):
        Repo(tmp_path)


def test_missing_path_raises(tmp_path):
    with pytest.raises(InvalidGitRepositoryError):
        Repo(tmp_path / "does-not-exist")


def test_status_reports_untracked_and_spaced_filenames(tmp_path):
    repo = _init_repo(tmp_path)
    (tmp_path / "a file.txt").write_text("hello\n")

    statuses = repo.status()

    assert len(statuses) == 1
    assert statuses[0].path == "a file.txt"
    assert statuses[0].index_status == "?"


def test_add_commit_log_roundtrip(tmp_path):
    repo = _init_repo(tmp_path)
    (tmp_path / "file.txt").write_text("hello\n")
    repo.add("file.txt")
    repo.commit("initial commit")

    commits = repo.log()

    assert len(commits) == 1
    assert commits[0].message == "initial commit"
    assert commits[0].author_email == "test@example.com"
    assert not repo.is_dirty()


def test_log_on_empty_repo_returns_empty_list(tmp_path):
    repo = _init_repo(tmp_path)
    assert repo.log() == []


def test_diff_shows_modification(tmp_path):
    repo = _init_repo(tmp_path)
    (tmp_path / "file.txt").write_text("hello\n")
    repo.add("file.txt")
    repo.commit("initial")
    (tmp_path / "file.txt").write_text("goodbye\n")

    assert "goodbye" in repo.diff()


def test_rename_is_tracked(tmp_path):
    repo = _init_repo(tmp_path)
    content = "hello world this is long enough to be detected as a rename\n"
    (tmp_path / "old.txt").write_text(content)
    repo.add("old.txt")
    repo.commit("add old")
    (tmp_path / "old.txt").rename(tmp_path / "new.txt")
    repo.add("new.txt", "old.txt")

    renamed = [s for s in repo.status() if s.orig_path]

    assert len(renamed) == 1
    assert renamed[0].path == "new.txt"
    assert renamed[0].orig_path == "old.txt"


def test_branch_create_and_checkout(tmp_path):
    repo = _init_repo(tmp_path)
    (tmp_path / "file.txt").write_text("hello\n")
    repo.add("file.txt")
    repo.commit("initial")

    repo.create_branch("feature")
    repo.checkout("feature")

    assert repo.current_branch() == "feature"
    branches = {b.name: b.is_current for b in repo.list_branches()}
    assert branches["feature"] is True


def test_git_command_error_on_nonexistent_branch(tmp_path):
    repo = _init_repo(tmp_path)
    with pytest.raises(GitCommandError):
        repo.checkout("does-not-exist")


def test_no_fd_leak_across_many_calls(tmp_path):
    repo = _init_repo(tmp_path)
    (tmp_path / "file.txt").write_text("hello\n")
    repo.add("file.txt")
    repo.commit("initial")

    fd_dir = Path("/proc/self/fd")
    if not fd_dir.exists():
        pytest.skip("requires /proc/self/fd (Linux)")

    before = len(os.listdir(fd_dir))
    for _ in range(200):
        repo.status()
        repo.log()
    after = len(os.listdir(fd_dir))

    assert after <= before