from unittest.mock import MagicMock

import pytest
from pydantic import ValidationError
from src.config import get_settings, presigned_url_ttl_seconds


@pytest.fixture(autouse=True)
def _clear_settings_cache() -> None:
    get_settings.cache_clear()


def _set_required_env(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setenv("ENVIRONMENT", "dev")
    monkeypatch.setenv("SQS_QUEUE_URL", "https://sqs.us-east-1.amazonaws.com/123/queue")
    monkeypatch.setenv("MESSAGE_PROCESSING_TIMEOUT_MINUTES", "30")
    monkeypatch.setenv("HEARTBEAT_INTERVAL_SECONDS", "60")


class TestGetSettings:
    def test_loads_settings(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)
        monkeypatch.delenv("SENTRY_DSN", raising=False)

        settings = get_settings()

        assert settings.ENVIRONMENT == "dev"
        assert settings.LOG_LEVEL == "INFO"
        assert settings.SENTRY_DSN is None
        assert settings.SQS_QUEUE_URL == "https://sqs.us-east-1.amazonaws.com/123/queue"

    def test_presigned_url_ttl_seconds_is_minutes_times_60(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)  # MESSAGE_PROCESSING_TIMEOUT_MINUTES = 30

        assert presigned_url_ttl_seconds() == 1800

    @pytest.mark.parametrize(
        "missing_var",
        ["ENVIRONMENT", "SQS_QUEUE_URL", "MESSAGE_PROCESSING_TIMEOUT_MINUTES", "HEARTBEAT_INTERVAL_SECONDS"],
    )
    def test_requires_env_var(self, monkeypatch: pytest.MonkeyPatch, missing_var: str) -> None:
        _set_required_env(monkeypatch)
        monkeypatch.delenv(missing_var, raising=False)

        with pytest.raises(ValidationError):
            get_settings()

    def test_rejects_invalid_environment(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)
        monkeypatch.setenv("ENVIRONMENT", "staging")

        with pytest.raises(ValidationError):
            get_settings()

    def test_non_dev_requires_sentry_dsn(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)
        monkeypatch.setenv("ENVIRONMENT", "prod")
        monkeypatch.delenv("SENTRY_DSN", raising=False)

        with pytest.raises(ValidationError, match="SENTRY_DSN is required in prod"):
            get_settings()

    def test_initializes_sentry_when_dsn_set(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)
        mock_init = MagicMock()
        monkeypatch.setattr("src.config.sentry_sdk.init", mock_init)
        monkeypatch.setenv("ENVIRONMENT", "prod")
        monkeypatch.setenv("SENTRY_DSN", "https://key@sentry.io/123")

        settings = get_settings()

        assert settings.ENVIRONMENT == "prod"
        mock_init.assert_called_once_with(
            dsn="https://key@sentry.io/123",
            environment="prod",
        )

    def test_dev_skips_sentry_when_dsn_not_set(self, monkeypatch: pytest.MonkeyPatch) -> None:
        _set_required_env(monkeypatch)
        mock_init = MagicMock()
        monkeypatch.setattr("src.config.sentry_sdk.init", mock_init)
        monkeypatch.delenv("SENTRY_DSN", raising=False)

        get_settings()

        mock_init.assert_not_called()


class TestNonEmptyStringValidation:
    @pytest.mark.parametrize(
        "value",
        [
            pytest.param("", id="empty"),
            pytest.param("   ", id="whitespace_only"),
        ],
    )
    def test_rejects_blank_queue_url(self, monkeypatch: pytest.MonkeyPatch, value: str) -> None:
        _set_required_env(monkeypatch)
        monkeypatch.setenv("SQS_QUEUE_URL", value)

        with pytest.raises(ValidationError):
            get_settings()