import os
from unittest.mock import patch
import pytest
from scouter.utils.connectors_config import (
    build_postgres_config,
    build_kafka_config,
    build_redis_config
)


@pytest.fixture
def mock_env_vars():
    with patch.dict(os.environ, {}, clear=True):
        yield


@pytest.mark.usefixtures("mock_env_vars")
def test_build_postgres_config_defaults():
    """Test that build_postgres_config returns default values when no env vars are set"""
    config = build_postgres_config()

    assert config == {
        'host': 'localhost',
        'port': 5432,
        'user': 'sientia',
        'password': 'sientia',
        'dbname': 'sientia',
        'min_connections': 5,
        'max_connections': 20
    }


@pytest.mark.usefixtures("mock_env_vars")
def test_build_postgres_config_with_env_vars():
    """Test that build_postgres_config uses env vars when set"""
    with patch.dict(os.environ, {
        'POSTGRES_HOST': 'db.example.com',
        'POSTGRES_PORT': '5433',
        'POSTGRES_USER': 'admin',
        'POSTGRES_PASSWORD': 'secret',
        'POSTGRES_DBNAME': 'test_db',
        'POSTGRES_MIN_CONNECTIONS': '3',
        'POSTGRES_MAX_CONNECTIONS': '15'
    }):
        config = build_postgres_config()

        assert config == {
            'host': 'db.example.com',
            'port': 5433,
            'user': 'admin',
            'password': 'secret',
            'dbname': 'test_db',
            'min_connections': 3,
            'max_connections': 15
        }


@pytest.mark.usefixtures("mock_env_vars")
def test_build_kafka_config_defaults():
    """Test that build_kafka_config returns default values when no env vars are set"""
    config = build_kafka_config()

    assert config == {
        'bootstrap_servers': 'localhost:9092',
        'polling_time': 1000,
        'group_id': 'scouter-group'
    }


@pytest.mark.usefixtures("mock_env_vars")
def test_build_kafka_config_with_env_vars():
    """Test that build_kafka_config uses env vars when set"""
    with patch.dict(os.environ, {
        'KAFKA_BOOTSTRAP_SERVERS': 'kafka.example.com:9092',
        'KAFKA_POLLING_TIME': '5000'
    }):
        config = build_kafka_config()

        assert config == {
            'bootstrap_servers': 'kafka.example.com:9092',
            'polling_time': 5000,
            'group_id': 'scouter-group'
        }


@pytest.mark.usefixtures("mock_env_vars")
def test_build_redis_config_defaults():
    """Test that build_redis_config returns default values when no env vars are set"""
    config = build_redis_config()

    assert config == {
        'host': 'localhost',
        'port': 6379
    }


@pytest.mark.usefixtures("mock_env_vars")
def test_build_redis_config_with_env_vars():
    """Test that build_redis_config uses env vars when set"""
    with patch.dict(os.environ, {
        'REDIS_HOST': 'redis.example.com',
        'REDIS_PORT': '6380'
    }):
        config = build_redis_config()

        assert config == {
            'host': 'redis.example.com',
            'port': 6380
        }