"""
Unit tests for configuration module.

Tests environment variable loading, validation, and error handling.
"""

import os
import pytest

from gondulf.config import Config, ConfigurationError


class TestConfigLoad:
    """Tests for Config.load() method."""

    def test_load_with_valid_secret_key(self, monkeypatch):
        """Test configuration loads successfully with valid SECRET_KEY."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        assert Config.SECRET_KEY == "a" * 32

    def test_load_missing_secret_key_raises_error(self, monkeypatch):
        """Test that missing SECRET_KEY raises ConfigurationError."""
        monkeypatch.delenv("GONDULF_SECRET_KEY", raising=False)
        with pytest.raises(ConfigurationError, match="GONDULF_SECRET_KEY is required"):
            Config.load()

    def test_load_short_secret_key_raises_error(self, monkeypatch):
        """Test that SECRET_KEY shorter than 32 chars raises error."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "short")
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        with pytest.raises(ConfigurationError, match="at least 32 characters"):
            Config.load()

    def test_load_database_url_default(self, monkeypatch):
        """Test DATABASE_URL defaults to sqlite:///./data/gondulf.db."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.delenv("GONDULF_DATABASE_URL", raising=False)
        Config.load()
        assert Config.DATABASE_URL == "sqlite:///./data/gondulf.db"

    def test_load_database_url_custom(self, monkeypatch):
        """Test DATABASE_URL can be customized."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.setenv("GONDULF_DATABASE_URL", "sqlite:////tmp/test.db")
        Config.load()
        assert Config.DATABASE_URL == "sqlite:////tmp/test.db"

    def test_load_smtp_configuration_defaults(self, monkeypatch):
        """Test SMTP configuration uses sensible defaults."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        for key in [
            "GONDULF_SMTP_HOST",
            "GONDULF_SMTP_PORT",
            "GONDULF_SMTP_USERNAME",
            "GONDULF_SMTP_PASSWORD",
            "GONDULF_SMTP_FROM",
            "GONDULF_SMTP_USE_TLS",
        ]:
            monkeypatch.delenv(key, raising=False)

        Config.load()

        assert Config.SMTP_HOST == "localhost"
        assert Config.SMTP_PORT == 587
        assert Config.SMTP_USERNAME is None
        assert Config.SMTP_PASSWORD is None
        assert Config.SMTP_FROM == "noreply@example.com"
        assert Config.SMTP_USE_TLS is True

    def test_load_smtp_configuration_custom(self, monkeypatch):
        """Test SMTP configuration can be customized."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.setenv("GONDULF_SMTP_HOST", "smtp.gmail.com")
        monkeypatch.setenv("GONDULF_SMTP_PORT", "465")
        monkeypatch.setenv("GONDULF_SMTP_USERNAME", "user@gmail.com")
        monkeypatch.setenv("GONDULF_SMTP_PASSWORD", "password123")
        monkeypatch.setenv("GONDULF_SMTP_FROM", "sender@example.com")
        monkeypatch.setenv("GONDULF_SMTP_USE_TLS", "false")

        Config.load()

        assert Config.SMTP_HOST == "smtp.gmail.com"
        assert Config.SMTP_PORT == 465
        assert Config.SMTP_USERNAME == "user@gmail.com"
        assert Config.SMTP_PASSWORD == "password123"
        assert Config.SMTP_FROM == "sender@example.com"
        assert Config.SMTP_USE_TLS is False

    def test_load_token_expiry_default(self, monkeypatch):
        """Test TOKEN_EXPIRY defaults to 3600 seconds."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.delenv("GONDULF_TOKEN_EXPIRY", raising=False)
        Config.load()
        assert Config.TOKEN_EXPIRY == 3600

    def test_load_code_expiry_default(self, monkeypatch):
        """Test CODE_EXPIRY defaults to 600 seconds."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.delenv("GONDULF_CODE_EXPIRY", raising=False)
        Config.load()
        assert Config.CODE_EXPIRY == 600

    def test_load_token_expiry_custom(self, monkeypatch):
        """Test TOKEN_EXPIRY can be customized."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.setenv("GONDULF_TOKEN_EXPIRY", "7200")
        Config.load()
        assert Config.TOKEN_EXPIRY == 7200

    def test_load_log_level_default_production(self, monkeypatch):
        """Test LOG_LEVEL defaults to INFO in production mode."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.delenv("GONDULF_LOG_LEVEL", raising=False)
        monkeypatch.delenv("GONDULF_DEBUG", raising=False)
        Config.load()
        assert Config.LOG_LEVEL == "INFO"
        assert Config.DEBUG is False

    def test_load_log_level_default_debug(self, monkeypatch):
        """Test LOG_LEVEL defaults to DEBUG when DEBUG=true."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.delenv("GONDULF_LOG_LEVEL", raising=False)
        monkeypatch.setenv("GONDULF_DEBUG", "true")
        Config.load()
        assert Config.LOG_LEVEL == "DEBUG"
        assert Config.DEBUG is True

    def test_load_log_level_custom(self, monkeypatch):
        """Test LOG_LEVEL can be customized."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.setenv("GONDULF_LOG_LEVEL", "WARNING")
        Config.load()
        assert Config.LOG_LEVEL == "WARNING"

    def test_load_invalid_log_level_raises_error(self, monkeypatch):
        """Test invalid LOG_LEVEL raises ConfigurationError."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        monkeypatch.setenv("GONDULF_LOG_LEVEL", "INVALID")
        with pytest.raises(ConfigurationError, match="must be one of"):
            Config.load()


class TestConfigValidate:
    """Tests for Config.validate() method."""

    def test_validate_valid_configuration(self, monkeypatch):
        """Test validation passes with valid configuration."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        Config.validate()  # Should not raise

    def test_validate_smtp_port_too_low(self, monkeypatch):
        """Test validation fails when SMTP_PORT < 1."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        Config.SMTP_PORT = 0
        with pytest.raises(ConfigurationError, match="must be between 1 and 65535"):
            Config.validate()

    def test_validate_smtp_port_too_high(self, monkeypatch):
        """Test validation fails when SMTP_PORT > 65535."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        Config.SMTP_PORT = 70000
        with pytest.raises(ConfigurationError, match="must be between 1 and 65535"):
            Config.validate()

    def test_validate_token_expiry_negative(self, monkeypatch):
        """Test validation fails when TOKEN_EXPIRY < 300."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        Config.TOKEN_EXPIRY = -1
        with pytest.raises(ConfigurationError, match="must be at least 300 seconds"):
            Config.validate()

    def test_validate_code_expiry_zero(self, monkeypatch):
        """Test validation fails when CODE_EXPIRY <= 0."""
        monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
        monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
        Config.load()
        Config.CODE_EXPIRY = 0
        with pytest.raises(ConfigurationError, match="must be positive"):
            Config.validate()