"""Tests for llm_backend.parse_backend + state machine."""

import os
import importlib
import sys


def test_parse_backend_groq_aliases():
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')
    for alias in ('groq', 'GROQ', 'cloud', 'облако', 'клауд', '  Groq  '):
        assert m.parse_backend(alias) == 'groq', f"failed: {alias!r}"


def test_parse_backend_ollama_aliases():
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')
    for alias in ('ollama', 'OLLAMA', 'local', 'локальный', 'локал', 'локальн'):
        assert m.parse_backend(alias) == 'ollama', f"failed: {alias!r}"


def test_parse_backend_unknown_returns_none():
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')
    assert m.parse_backend('openai') is None
    assert m.parse_backend('claude') is None
    assert m.parse_backend('') is None
    assert m.parse_backend(None) is None


def test_persist_round_trip(tmp_path, monkeypatch):
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')
    monkeypatch.setattr(m, '_CHOICE_FILE', str(tmp_path / 'llm_backend.txt'))
    m._persist('ollama')
    assert m._read_persisted() == 'ollama'
    m._persist('groq')
    assert m._read_persisted() == 'groq'


def test_auto_detect_fallback_to_ollama(tmp_path, monkeypatch):
    """When no GROQ_TOKEN in config, auto-detect should pick ollama."""
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')

    # Mock config module with no GROQ_TOKEN
    class FakeConfig:
        GROQ_TOKEN = ''
    monkeypatch.setitem(sys.modules, 'config', FakeConfig())

    assert m._auto_detect_backend() == 'ollama'


def test_auto_detect_picks_groq_when_token_present(tmp_path, monkeypatch):
    if 'llm_backend' in sys.modules:
        del sys.modules['llm_backend']
    m = importlib.import_module('llm_backend')

    class FakeConfig:
        GROQ_TOKEN = 'gsk_fake_test_token'
    monkeypatch.setitem(sys.modules, 'config', FakeConfig())

    assert m._auto_detect_backend() == 'groq'