import pytest
from pydantic import ValidationError

from app.config import AlertsConfig, Settings


def _clear_alert_env(monkeypatch: pytest.MonkeyPatch) -> None:
    for name in (
        "G2S_ALERTS__TELEGRAM_ENABLED",
        "G2S_ALERTS__TELEGRAM_BOT_TOKEN",
        "G2S_ALERTS__TELEGRAM_CHAT_ID",
    ):
        monkeypatch.delenv(name, raising=False)


def test_alerts_settings_are_loaded_from_yaml(tmp_path, monkeypatch) -> None:
    _clear_alert_env(monkeypatch)
    config_file = tmp_path / "config.yaml"
    config_file.write_text(
        """
alerts:
  telegram_enabled: true
  telegram_bot_token: "bot-token"
  telegram_chat_id: "-100777"
  provider_5xx:
    error_count: 7
    window_minutes: 6
  provider_p99_latency:
    threshold_ms: 5200
    window_minutes: 11
  provider_unavailable:
    duration_minutes: 8
""".strip(),
        encoding="utf-8",
    )
    monkeypatch.setenv("G2S_CONFIG_FILE", str(config_file))

    settings = Settings()

    assert settings.alerts.telegram_enabled is True
    assert settings.alerts.telegram_bot_token == "bot-token"
    assert settings.alerts.telegram_chat_id == "-100777"
    assert settings.alerts.provider_5xx.error_count == 7
    assert settings.alerts.provider_5xx.window_minutes == 6
    assert settings.alerts.provider_p99_latency.threshold_ms == 5200
    assert settings.alerts.provider_p99_latency.window_minutes == 11
    assert settings.alerts.provider_unavailable.duration_minutes == 8


@pytest.mark.parametrize(
    ("yaml_body", "error_message"),
    [
        (
            """
alerts:
  telegram_enabled: true
  telegram_chat_id: "-100777"
""".strip(),
            "alerts.telegram_bot_token is required when alerts.telegram_enabled=true",
        ),
        (
            """
alerts:
  telegram_enabled: true
  telegram_bot_token: "bot-token"
""".strip(),
            "alerts.telegram_chat_id is required when alerts.telegram_enabled=true",
        ),
    ],
)
def test_enabled_telegram_requires_credentials(
    tmp_path,
    monkeypatch,
    yaml_body: str,
    error_message: str,
) -> None:
    _clear_alert_env(monkeypatch)
    config_file = tmp_path / "config.yaml"
    config_file.write_text(yaml_body, encoding="utf-8")
    monkeypatch.setenv("G2S_CONFIG_FILE", str(config_file))

    with pytest.raises(ValidationError, match=error_message):
        Settings()


def test_alert_condition_defaults_match_required_thresholds() -> None:
    alerts = AlertsConfig()

    assert alerts.provider_5xx.error_count == 5
    assert alerts.provider_5xx.window_minutes == 5
    assert alerts.provider_p99_latency.threshold_ms == 5000
    assert alerts.provider_p99_latency.window_minutes == 10
    assert alerts.provider_unavailable.duration_minutes == 5