from __future__ import annotations

import os
import shutil
import subprocess
from pathlib import Path

from repo_manager.provenance import assistant_report, install_hook

SOURCE_HOOK = Path(__file__).parents[1] / ".githooks" / "prepare-commit-msg"
ASSISTANT_ENV_PREFIXES = ("ASSISTANT_", "CLAUDE", "CODEX_", "GROK", "XAI_")


def _human_env() -> dict[str, str]:
    return {
        key: value
        for key, value in os.environ.items()
        if not any(key.startswith(prefix) for prefix in ASSISTANT_ENV_PREFIXES)
    }


def _git(repo: Path, *args: str, env: dict[str, str] | None = None) -> None:
    subprocess.run(["git", *args], cwd=repo, env=env, check=True, capture_output=True)


def _fixture(tmp_path: Path) -> Path:
    repo = tmp_path / "pilot"
    repo.mkdir()
    _git(repo, "init")
    _git(repo, "config", "user.email", "test@example.com")
    _git(repo, "config", "user.name", "Test")
    hooks = repo / ".githooks"
    hooks.mkdir()
    shutil.copy2(SOURCE_HOOK, hooks / "prepare-commit-msg")
    (hooks / "prepare-commit-msg").chmod(0o755)
    _git(repo, "config", "core.hooksPath", str(hooks))
    return repo


def _commit(repo: Path, name: str, *, session: str | None = None) -> None:
    (repo / name).write_text(name, encoding="utf-8")
    _git(repo, "add", name)
    env = _human_env()
    if session:
        env.update(
            ASSISTANT_NAME="codex",
            ASSISTANT_MODEL="gpt-test",
            ASSISTANT_PROCESS="42@test-host",
            ASSISTANT_SESSION=session,
        )
    _git(repo, "commit", "-m", name, env=env)


def test_hook_is_silent_for_humans_and_idempotent_for_assistants(tmp_path: Path) -> None:
    message = tmp_path / "message"
    message.write_text("Change records\n", encoding="utf-8")
    subprocess.run([str(SOURCE_HOOK), str(message)], env=_human_env(), check=True)
    assert message.read_text(encoding="utf-8") == "Change records\n"

    env = _human_env()
    env.update(
        ASSISTANT_NAME="codex",
        ASSISTANT_MODEL="gpt-test",
        ASSISTANT_PROCESS="42@test-host",
        ASSISTANT_SESSION="session-a",
    )
    subprocess.run([str(SOURCE_HOOK), str(message)], env=env, check=True)
    subprocess.run([str(SOURCE_HOOK), str(message)], env=env, check=True)
    text = message.read_text(encoding="utf-8")
    assert text.count("Assistant: codex") == 1
    assert text.count("Assistant-Model: gpt-test") == 1
    assert text.count("Assistant-Session: session-a") == 1


def test_report_detects_interleaved_sessions_and_unknown_human(tmp_path: Path) -> None:
    repo = _fixture(tmp_path)
    _commit(repo, "human")
    _commit(repo, "a1", session="session-a")
    _commit(repo, "b1", session="session-b")
    _commit(repo, "a2", session="session-a")

    report = assistant_report(repo)
    assert report["assistants"]["codex"]["commit_count"] == 3
    assert report["assistants"]["codex"]["models"] == ["gpt-test"]
    assert report["interleaved_sessions"] == [["session-a", "session-b"]]
    assert report["unattributed"]["before_cutover"] == 1


def test_install_sets_only_global_hooks_path(tmp_path: Path, monkeypatch) -> None:
    hooks = tmp_path / "hooks"
    hooks.mkdir()
    shutil.copy2(SOURCE_HOOK, hooks / "prepare-commit-msg")
    (hooks / "prepare-commit-msg").chmod(0o755)
    global_config = tmp_path / "gitconfig"
    monkeypatch.setenv("GIT_CONFIG_GLOBAL", str(global_config))
    result = install_hook(hooks)
    assert result["ok"] is True
    configured = subprocess.run(
        ["git", "config", "--global", "--get", "core.hooksPath"],
        check=True,
        capture_output=True,
        text=True,
        env={**os.environ, "GIT_CONFIG_GLOBAL": str(global_config)},
    ).stdout.strip()
    assert configured == str(hooks.resolve())