import pytest

import config
from config import ConfigError, get_settings


@pytest.fixture(autouse=True)
def clear_settings_cache():
    get_settings.cache_clear()
    yield
    get_settings.cache_clear()


@pytest.fixture
def base_env(monkeypatch):
    monkeypatch.setenv("OPENROUTER_API_KEY", "test-key")
    for name in ("OPENROUTER_MODEL", "LLM_TEMPERATURE", "LLM_MAX_TOKENS", "SKILL_MAX_TOKENS", "ATS_MAX_TOKENS", "MAX_HISTORY_TURNS",
                 "CANDIDATE_NAME", "DATA_DIR", "LANGFUSE_HOST", "LANGFUSE_BASE_URL",
                 "LANGFUSE_PUBLIC_KEY", "LANGFUSE_SECRET_KEY"):
        monkeypatch.delenv(name, raising=False)


def test_missing_api_key_is_rejected(base_env, monkeypatch):
    monkeypatch.setenv("OPENROUTER_API_KEY", "   ")
    with pytest.raises(ConfigError, match="OPENROUTER_API_KEY"):
        get_settings()


def test_api_key_can_be_supplied_later_by_the_ui(base_env, monkeypatch):
    monkeypatch.delenv("OPENROUTER_API_KEY")

    settings = get_settings(require_api_key=False)

    assert settings.openrouter_api_key == ""


@pytest.mark.parametrize("var", ["LLM_TEMPERATURE", "LLM_MAX_TOKENS", "SKILL_MAX_TOKENS", "ATS_MAX_TOKENS", "MAX_HISTORY_TURNS"])
def test_non_numeric_values_are_rejected(base_env, monkeypatch, var):
    monkeypatch.setenv(var, "hot")
    with pytest.raises(ConfigError, match=var):
        get_settings()


def test_defaults_apply_when_optional_vars_are_unset(base_env):
    settings = get_settings()
    assert settings.openrouter_api_key == "test-key"
    assert settings.model == config.DEFAULT_MODEL
    assert settings.temperature == config.DEFAULT_TEMPERATURE
    assert settings.max_tokens == config.DEFAULT_MAX_TOKENS
    assert settings.max_history_turns == config.DEFAULT_MAX_HISTORY_TURNS
    assert settings.skill_max_tokens == config.DEFAULT_SKILL_MAX_TOKENS == 6500
    assert settings.ats_max_tokens == config.DEFAULT_ATS_MAX_TOKENS == 12000
    assert settings.candidate_name == "the candidate"


def test_overrides_are_read_from_the_environment(base_env, monkeypatch):
    monkeypatch.setenv("OPENROUTER_MODEL", "some/other-model")
    monkeypatch.setenv("LLM_TEMPERATURE", "0.7")
    monkeypatch.setenv("ATS_MAX_TOKENS", "9000")
    monkeypatch.setenv("MAX_HISTORY_TURNS", "3")
    settings = get_settings()
    assert settings.model == "some/other-model"
    assert settings.temperature == 0.7
    assert settings.ats_max_tokens == 9000
    assert settings.max_history_turns == 3


def test_ats_llm_uses_its_separate_response_cap(base_env):
    from graph import build_llm

    settings = get_settings()

    assert build_llm(max_tokens=settings.ats_max_tokens).max_tokens == 12000


def test_settings_do_not_require_a_data_directory(base_env, monkeypatch, tmp_path):
    monkeypatch.setenv("DATA_DIR", str(tmp_path / "missing"))

    settings = get_settings()

    assert not hasattr(settings, "data_dir")


class TestLangfuseHost:
    """LANGFUSE_BASE_URL is an alias; getting this wrong silently traced to the wrong region."""

    def test_defaults_when_neither_is_set(self, base_env):
        assert get_settings().langfuse_host == config.DEFAULT_LANGFUSE_HOST

    def test_base_url_alias_is_honoured(self, base_env, monkeypatch):
        monkeypatch.setenv("LANGFUSE_BASE_URL", "https://us.cloud.langfuse.com")
        assert get_settings().langfuse_host == "https://us.cloud.langfuse.com"

    def test_host_wins_over_the_alias(self, base_env, monkeypatch):
        monkeypatch.setenv("LANGFUSE_HOST", "https://host.example")
        monkeypatch.setenv("LANGFUSE_BASE_URL", "https://alias.example")
        assert get_settings().langfuse_host == "https://host.example"


class TestTracingEnabled:
    def test_off_without_keys(self, base_env):
        assert get_settings().tracing_enabled is False

    def test_off_with_only_one_key(self, base_env, monkeypatch):
        monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk")
        assert get_settings().tracing_enabled is False

    def test_on_with_both_keys(self, base_env, monkeypatch):
        monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk")
        monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk")
        assert get_settings().tracing_enabled is True