"""
Unit tests for the ConfigManager module.
"""

import pytest
import tempfile
import os
import yaml
from pathlib import Path
from unittest.mock import patch, mock_open

from src.config_manager import ConfigManager


class TestConfigManager:
    """Test cases for ConfigManager class."""
    
    def test_init_with_default_path(self):
        """Test ConfigManager initialization with default path."""
        config_manager = ConfigManager()
        assert config_manager.config_path == Path("config/config.yaml")
        assert isinstance(config_manager.config, dict)
        assert isinstance(config_manager.default_config, dict)
    
    def test_init_with_custom_path(self):
        """Test ConfigManager initialization with custom path."""
        custom_path = "custom/config.yaml"
        config_manager = ConfigManager(custom_path)
        assert config_manager.config_path == Path(custom_path)
    
    def test_get_default_config(self):
        """Test default configuration structure."""
        config_manager = ConfigManager()
        default_config = config_manager._get_default_config()
        
        # Check required sections
        assert "scraper" in default_config
        assert "sources" in default_config
        assert "output" in default_config
        assert "database" in default_config
        assert "analysis" in default_config
        
        # Check some default values
        assert default_config["scraper"]["delay_between_requests"] == 1.0
        assert default_config["scraper"]["timeout"] == 30
        assert default_config["scraper"]["headless"] is True
        assert isinstance(default_config["sources"], list)
        assert len(default_config["sources"]) > 0
    
    @patch('builtins.open', new_callable=mock_open, read_data="scraper:\n  timeout: 60")
    @patch('pathlib.Path.exists')
    def test_load_config_existing_file(self, mock_exists, mock_file):
        """Test loading configuration from existing file."""
        mock_exists.return_value = True
        
        config_manager = ConfigManager()
        config = config_manager.load_config()
        
        mock_file.assert_called_once()
        assert config["scraper"]["timeout"] == 60
    
    @patch('builtins.open', new_callable=mock_open)
    @patch('pathlib.Path.exists')
    def test_load_config_create_default(self, mock_exists, mock_file):
        """Test creating default configuration when file doesn't exist."""
        mock_exists.return_value = False
        
        config_manager = ConfigManager()
        config = config_manager.load_config()
        
        # Verify file was created
        mock_file.assert_called_once()
        # Verify config is default
        assert config == config_manager.default_config
    
    @patch('builtins.open', new_callable=mock_open)
    def test_save_config(self, mock_file):
        """Test saving configuration to file."""
        config_manager = ConfigManager()
        config_manager.config = {"test": "value"}
        
        config_manager.save_config()
        
        mock_file.assert_called_once()
        # Verify yaml.dump was called with correct arguments
        with patch('yaml.dump') as mock_dump:
            config_manager.save_config()
            mock_dump.assert_called_once()
    
    def test_validate_and_merge_config(self):
        """Test configuration validation and merging."""
        config_manager = ConfigManager()
        
        # Test with partial config
        partial_config = {
            "scraper": {
                "timeout": 60
            }
        }
        config_manager.config = partial_config
        
        merged = config_manager._validate_and_merge_config()
        
        # Should have all sections
        assert "sources" in merged
        assert "output" in merged
        # Should have updated value
        assert merged["scraper"]["timeout"] == 60
        # Should have default values for missing keys
        assert merged["scraper"]["delay_between_requests"] == 1.0
    
    def test_validate_and_merge_config_missing_required(self):
        """Test validation fails when required sections are missing."""
        config_manager = ConfigManager()
        config_manager.config = {"invalid": "config"}
        
        with pytest.raises(ValueError, match="Missing required configuration section"):
            config_manager._validate_and_merge_config()
    
    def test_validate_and_merge_config_no_sources(self):
        """Test validation fails when no sources are configured."""
        config_manager = ConfigManager()
        config_manager.config = {
            "scraper": {},
            "sources": [],
            "output": {}
        }
        
        with pytest.raises(ValueError, match="At least one data source must be configured"):
            config_manager._validate_and_merge_config()
    
    def test_get_with_dot_notation(self):
        """Test getting configuration values with dot notation."""
        config_manager = ConfigManager()
        config_manager.config = {
            "scraper": {
                "timeout": 60,
                "nested": {
                    "value": "test"
                }
            }
        }
        
        assert config_manager.get("scraper.timeout") == 60
        assert config_manager.get("scraper.nested.value") == "test"
        assert config_manager.get("nonexistent", "default") == "default"
    
    def test_set_with_dot_notation(self):
        """Test setting configuration values with dot notation."""
        config_manager = ConfigManager()
        config_manager.config = {"scraper": {}}
        
        config_manager.set("scraper.timeout", 60)
        config_manager.set("new.nested.value", "test")
        
        assert config_manager.config["scraper"]["timeout"] == 60
        assert config_manager.config["new"]["nested"]["value"] == "test"
    
    @patch.object(ConfigManager, 'load_config')
    def test_reload(self, mock_load):
        """Test reloading configuration."""
        config_manager = ConfigManager()
        config_manager.reload()
        
        mock_load.assert_called_once()