"""Tests for tagsync.detect: platform detection + Dropbox folder probing."""
from __future__ import annotations

import importlib
import json

import pytest


@pytest.fixture
def detect_module():
    from tagsync import detect
    return importlib.reload(detect)


def test_detect_platform_returns_known_value(detect_module):
    assert detect_module.detect_platform() in {"macos", "windows", "linux"}


def test_platform_label_nonempty(detect_module):
    assert detect_module.platform_label()


def test_python_label_nonempty(detect_module):
    label = detect_module.python_label()
    assert label.startswith("Python ")


def test_has_module_true_for_stdlib(detect_module):
    assert detect_module.has_module("json")
    assert detect_module.has_module("pathlib")


def test_has_module_false_for_garbage(detect_module):
    assert not detect_module.has_module("definitely_not_a_real_module_xyz")


def test_detect_dropbox_folder_from_info_json(detect_module, tmp_path, monkeypatch):
    """When Dropbox's info.json exists, we should parse its path field."""
    dropbox_dir = tmp_path / "Dropbox"
    dropbox_dir.mkdir()
    info_dir = tmp_path / ".dropbox"
    info_dir.mkdir()
    info = info_dir / "info.json"
    info.write_text(json.dumps({
        "personal": {"path": str(dropbox_dir), "host": 12345},
    }))

    monkeypatch.setattr(
        detect_module,
        "_dropbox_info_candidates",
        lambda: [info],
    )
    result = detect_module.detect_dropbox_folder()
    assert result == dropbox_dir


def test_detect_dropbox_folder_handles_malformed_json(detect_module, tmp_path, monkeypatch):
    info = tmp_path / "info.json"
    info.write_text("not valid json {{{")

    monkeypatch.setattr(
        detect_module,
        "_dropbox_info_candidates",
        lambda: [info],
    )
    # Should fall back silently, not raise.
    result = detect_module.detect_dropbox_folder()
    # No fallback path in tmp, so None is acceptable.
    assert result is None or result.is_dir()


def test_detect_dropbox_folder_returns_none_if_missing(detect_module, monkeypatch):
    from pathlib import Path
    monkeypatch.setattr(detect_module, "_dropbox_info_candidates", lambda: [])
    monkeypatch.setattr(Path, "home", staticmethod(lambda: Path("/definitely/does/not/exist")))
    assert detect_module.detect_dropbox_folder() is None


def test_detect_dropbox_folder_prefers_personal_over_business(detect_module, tmp_path, monkeypatch):
    personal = tmp_path / "Dropbox-Personal"
    business = tmp_path / "Dropbox-Business"
    personal.mkdir()
    business.mkdir()
    info = tmp_path / "info.json"
    info.write_text(json.dumps({
        "personal": {"path": str(personal)},
        "business": {"path": str(business)},
    }))
    monkeypatch.setattr(
        detect_module,
        "_dropbox_info_candidates",
        lambda: [info],
    )
    assert detect_module.detect_dropbox_folder() == personal


def test_find_exiftool_uses_shutil_which(detect_module, monkeypatch):
    import shutil
    monkeypatch.setattr(shutil, "which", lambda name: "/usr/bin/exiftool" if name == "exiftool" else None)
    result = detect_module.find_exiftool()
    assert result is not None
    assert result.name == "exiftool"


def test_find_exiftool_returns_none_when_absent(detect_module, monkeypatch):
    import shutil
    monkeypatch.setattr(shutil, "which", lambda _name: None)
    assert detect_module.find_exiftool() is None