Settings Manager

This document explains the technical implementation of the Settings Manager component in the Punch Card Project.

Overview

The Settings Manager provides a centralized system for accessing, validating, and persisting application settings. It replaces the previous approach of scattered settings access throughout the codebase with a single, type-safe interface.

Key Features

• Centralized Configuration: Single point of access for all application settings
• Type Safety: Settings are accessed with proper type validation
• Automatic Persistence: Settings changes are automatically tracked and saved
• Organized Categories: Settings are grouped by functionality for better organization
• Default Values: Sensible defaults are provided for all settings
• Error Handling: Robust error handling for configuration loading and saving

Implementation

Core Components

The Settings Manager is built around these key components:

1. SettingsManager Class: Central class that manages all settings access
2. Settings Categories: Organization of settings into logical groups
3. Settings Dialog: UI component for modifying settings
4. Settings Storage: Persistence layer for saving settings

SettingsManager Class

The SettingsManager class provides a simple interface for accessing settings:

class SettingsManager:
    def __init__(self):
        self.settings = {}
        self.load_settings()
        
    def get(self, key, default=None, type_hint=None):
        """Get a setting with optional type validation"""
        value = self.settings.get(key, default)
        
        # Apply type conversion if needed
        if type_hint and value is not None:
            try:
                value = type_hint(value)
            except (ValueError, TypeError):
                return default
                
        return value
        
    def set(self, key, value):
        """Set a setting and trigger persistence"""
        self.settings[key] = value
        self.save_settings()
        
    def load_settings(self):
        """Load settings from storage"""
        try:
            # Load from file
            # ...
        except Exception as e:
            # Error handling
            # ...
            
    def save_settings(self):
        """Save settings to storage"""
        try:
            # Save to file
            # ...
        except Exception as e:
            # Error handling
            # ...

Settings Categories

Settings are organized into logical categories:

• General: Application-wide settings
• Display: Visual appearance and behavior settings
• Animation: Animation timing and behavior
• API: External API configuration
• Hardware: Hardware connectivity settings
• Debug: Debugging and development settings

Using the Settings Manager

To access settings from anywhere in the code:

# Get the singleton instance
settings = SettingsManager.instance()

# Get settings with type safety
delay = settings.get('animation.delay', 100, int)
api_key = settings.get('api.key', '')
show_debug = settings.get('debug.enabled', False, bool)

# Update settings
settings.set('animation.delay', 150)

Settings Dialog

The Settings Dialog provides a user interface for modifying settings:

• Tabbed Interface: Settings are organized into tabs by category
• Type-Appropriate Controls: Different control types for different setting types
• Validation: Input validation prevents invalid settings
• Apply/Cancel: Changes can be previewed before saving

Security Considerations

The Settings Manager integrates with the keychain system for secure storage of sensitive settings:

• API keys are stored in the system keychain rather than in settings files
• Sensitive settings are never saved to disk in plaintext
• Access to secure settings requires proper authorization

Known Issues

• Some settings aren't properly preserved between sessions
• Large configuration files can cause loading delays
• Settings dialog may not immediately reflect changes made programmatically

Future Improvements

Planned enhancements to the Settings Manager:

1. Schema Validation: Formal schema definition for settings structure
2. Change Notifications: Event system for settings changes
3. Profile Support: Multiple configuration profiles for different uses
4. Import/Export: Configuration import and export functionality
5. User Permissions: Different access levels for settings

Integration with Other Components

The Settings Manager works closely with other system components:

• Animation Manager: Provides animation settings
• Hardware Controller: Provides hardware configuration
• API Client: Manages API connection details
• UI Components: Controls appearance and behavior