"""Tests for myagents.launcher.ensure_backend / guided auto-install."""

from __future__ import annotations

import os
from pathlib import Path
from unittest.mock import patch

from myagents import launcher as launcher_mod


class TestEnsureBackend:
    def test_already_available_skips_install(self) -> None:
        with (
            patch.object(
                launcher_mod,
                "_resolve_backend_binary",
                return_value="/usr/bin/claude",
            ),
            patch.object(launcher_mod, "_offer_install") as offer,
        ):
            assert launcher_mod.ensure_backend("claude") is True
            offer.assert_not_called()

    def test_noninteractive_auto_installs(self) -> None:
        with (
            patch.object(
                launcher_mod, "_resolve_backend_binary", return_value=None
            ),
            patch.object(launcher_mod, "_is_interactive", return_value=False),
            patch.object(
                launcher_mod, "_run_install", return_value="/opt/bin/claude"
            ) as run_install,
            patch.object(launcher_mod, "click") as click_mod,
        ):
            assert launcher_mod.ensure_backend("claude") is True
            run_install.assert_called_once()
            click_mod.prompt.assert_not_called()

    def test_yes_true_skips_prompt(self) -> None:
        with (
            patch.object(
                launcher_mod, "_resolve_backend_binary", return_value=None
            ),
            patch.object(
                launcher_mod, "_run_install", return_value="/opt/bin/claude"
            ) as run_install,
            patch.object(launcher_mod, "click") as click_mod,
        ):
            assert launcher_mod.ensure_backend("claude", yes=True) is True
            run_install.assert_called_once()
            click_mod.prompt.assert_not_called()

    def test_unknown_backend_false(self) -> None:
        assert launcher_mod.ensure_backend("nope") is False

    def test_hermes_cannot_auto_install(self) -> None:
        with (
            patch.object(
                launcher_mod, "_resolve_backend_binary", return_value=None
            ),
            patch.object(launcher_mod, "_is_interactive", return_value=False),
        ):
            assert launcher_mod.ensure_backend("hermes") is False


class TestResolveBackendBinary:
    def test_falls_back_to_npm_global_bin(self, tmp_path: Path, monkeypatch) -> None:
        bin_dir = tmp_path / "bin"
        bin_dir.mkdir()
        claude = bin_dir / "claude"
        claude.write_text("#!/bin/sh\n")
        claude.chmod(0o755)
        monkeypatch.delenv("CLAUDE_BIN", raising=False)
        with (
            patch.object(launcher_mod.shutil, "which", return_value=None),
            patch.object(launcher_mod, "_npm_global_bin", return_value=bin_dir),
        ):
            assert launcher_mod.resolve_backend_binary("claude") == str(claude)

    def test_ensure_npm_bin_prepends_path(
        self, tmp_path: Path, monkeypatch
    ) -> None:
        bin_dir = tmp_path / "npm-bin"
        bin_dir.mkdir()
        monkeypatch.setenv("PATH", "/usr/bin")
        with patch.object(launcher_mod, "_npm_global_bin", return_value=bin_dir):
            got = launcher_mod.ensure_npm_bin_on_path(persist=False)
        assert got == bin_dir
        assert str(bin_dir) in os.environ["PATH"].split(os.pathsep)
        assert os.environ["PATH"].split(os.pathsep)[0] == str(bin_dir)


class TestOfferInstallGuided:
    def test_interactive_default_yes_when_npm_present(self) -> None:
        cfg = launcher_mod._BACKENDS["claude"]
        with (
            patch.object(launcher_mod, "_is_interactive", return_value=True),
            patch.object(
                launcher_mod.shutil, "which", return_value="/usr/bin/npm"
            ),
            patch.object(
                launcher_mod, "_run_install", return_value="/opt/bin/claude"
            ) as run_install,
            patch.object(
                launcher_mod.click,
                "prompt",
                return_value="y",
            ) as prompt,
        ):
            assert (
                launcher_mod._offer_install(cfg, yes=None) == "/opt/bin/claude"
            )
            prompt.assert_called_once()
            assert prompt.call_args.kwargs.get("default") == "y"
            run_install.assert_called_once()