Constants Reference

This document provides comprehensive documentation for all constants used throughout the GenHub application. Constants are defined in static classes within the GenHub.Core.Constants namespace and follow StyleCop conventions.

Overview

GenHub uses a centralized constants system to ensure consistency across the application. Constants are organized into logical groups for better maintainability and consistency.

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ApiConstants Class

API and network related constants.

User Agents

• DefaultUserAgent: Default user agent string for HTTP requests (constructed as "GenHub/1.0" from AppConstants.ApplicationName and AppConstants.Version)

GitHub

• GitHubDomain: GitHub domain name ("github.com")
• GitHubUrlRegexPattern: Regex pattern for parsing repository URLs
  (@"^https://github\.com/(?<owner>[^/]+)/(?<repo>[^/]+)(?:/releases/tag/(?<tag>[^/]+))?")

UriConstants

URI scheme constants for handling different types of URIs and paths.

• AvarUriScheme: URI scheme for Avalonia embedded resources ("avares://")
• HttpUriScheme: HTTP URI scheme ("http://")
• HttpsUriScheme: HTTPS URI scheme ("https://")
• GeneralsIconUri: Icon URI for Generals game type ("avares://GenHub/Assets/Icons/generals-icon.png")
• ZeroHourIconUri: Icon URI for Zero Hour game type ("avares://GenHub/Assets/Icons/zerohour-icon.png")
• DefaultIconUri: Default icon URI for unknown game types ("avares://GenHub/Assets/Icons/generalshub-icon.png")

AppConstants

Application-wide constants for GenHub.

Constant	Value	Description
ApplicationName	"GenHub"	Application name
Version	"1.0"	Current version of GenHub
DefaultTheme	Theme.Dark	Default UI theme
DefaultThemeName	"Dark"	Default theme name as string
DefaultUserAgent	"GenHub/1.0"	Default user agent string

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CasDefaults Class

Default values and limits for Content-Addressable Storage (CAS).

Constant	Value	Description
MaxCacheSizeBytes	53687091200 (50GB)	Default maximum cache size
DefaultMaxCacheSizeGB	50	Default maximum cache size in gigabytes
MaxConcurrentOperations	4	Default maximum concurrent CAS operations
GcGracePeriodDays	7	Default garbage collection grace period in days

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ConfigurationKeys Class

Configuration key constants for appsettings.json and environment variables.

Workspace Configuration

• WorkspaceDefaultPath: "GenHub:Workspace:DefaultPath"
• WorkspaceDefaultStrategy: "GenHub:Workspace:DefaultStrategy"

Cache Configuration

• CacheDefaultPath: "GenHub:Cache:DefaultPath"

UI Configuration

• UiDefaultTheme: "GenHub:UI:DefaultTheme"
• UiDefaultWindowWidth: "GenHub:UI:DefaultWindowWidth"
• UiDefaultWindowHeight: "GenHub:UI:DefaultWindowHeight"

Downloads Configuration

• DownloadsDefaultTimeoutSeconds: "GenHub:Downloads:DefaultTimeoutSeconds"
• DownloadsDefaultUserAgent: "GenHub:Downloads:DefaultUserAgent"
• DownloadsDefaultMaxConcurrent: "GenHub:Downloads:DefaultMaxConcurrent"
• DownloadsDefaultBufferSize: "GenHub:Downloads:DefaultBufferSize"

Downloads Policy Configuration

• DownloadsPolicyMinConcurrent: "GenHub:Downloads:Policy:MinConcurrent"
• DownloadsPolicyMaxConcurrent: "GenHub:Downloads:Policy:MaxConcurrent"
• DownloadsPolicyMinTimeoutSeconds: "GenHub:Downloads:Policy:MinTimeoutSeconds"
• DownloadsPolicyMaxTimeoutSeconds: "GenHub:Downloads:Policy:MaxTimeoutSeconds"
• DownloadsPolicyMinBufferSizeBytes: "GenHub:Downloads:Policy:MinBufferSizeBytes"
• DownloadsPolicyMaxBufferSizeBytes: "GenHub:Downloads:Policy:MaxBufferSizeBytes"

App Data Configuration

• AppDataPath: "GenHub:AppDataPath"

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ConversionConstants Class

Constants for unit conversions used throughout the application.

• BytesPerKilobyte: 1024
• BytesPerMegabyte: 1048576
• BytesPerGigabyte: 1073741824

Color Conversion Constants

• LuminanceRedCoefficient: Coefficient for red channel in luminance calculation (0.299)
• LuminanceGreenCoefficient: Coefficient for green channel in luminance calculation (0.587)
• LuminanceBlueCoefficient: Coefficient for blue channel in luminance calculation (0.114)
• BrightnessThreshold: Threshold value for determining if a color is light or dark (0.5)

DirectoryNames

Directory names used for organizing content storage.

Constant	Value	Description
Data	"Data"	Directory for content data
Cache	"Cache"	Directory for cache files
CasPool	"cas-pool"	Directory for CAS pool
Temp	"Temp"	Directory for temporary files
Logs	"Logs"	Directory for log files
Backups	"Backups"	Directory for backup files

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DownloadDefaults Class

Default values and limits for download operations.

• BufferSizeBytes: 81920
• BufferSizeKB: 80.0
• MinBufferSizeKB: 4.0
• MaxBufferSizeKB: 1024.0
• MaxConcurrentDownloads: 3
• MaxRetryAttempts: 3
• TimeoutSeconds: 600

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FileTypes Class

File and directory name constants to prevent typos and ensure consistency.

Manifest Files

Constant	Value	Description
ManifestsDirectory	"Manifests"	Directory for manifest files
ManifestFilePattern	"*.manifest.json"	File pattern for manifest files
ManifestFileExtension	".manifest.json"	File extension for manifest files

JSON Files

Constant	Value	Description
JsonFileExtension	".json"	File extension for JSON files
JsonFilePattern	"*.json"	File pattern for JSON files
SettingsFileName	"settings.json"	Default settings file name

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ManifestConstants Class

Constants related to manifest ID generation, validation, and file operations.

Manifest ID Generation

Constant	Value	Description
DefaultManifestSchemaVersion	1	Default manifest schema version
PublisherContentIdPrefix	"publisher"	Prefix for publisher content IDs
BaseGameIdPrefix	"basegame"	Prefix for base game IDs
SimpleIdPrefix	"simple"	Prefix for simple test IDs

Manifest Validation

Constant	Value	Description
MaxManifestIdLength	256	Maximum length for manifest IDs
MinManifestIdLength	3	Minimum length for manifest IDs
MaxManifestSegments	5	Maximum number of segments in manifest ID
MinManifestSegments	1	Minimum number of segments in manifest ID

Manifest ID Regex Patterns

Constant	Description
PublisherIdRegexPattern	Regex for publisher content IDs
GameInstallationIdRegexPattern	Regex for base game IDs
SimpleIdRegexPattern	Regex for simple IDs

Publisher Content ID Pattern:

^(?:[a-zA-Z0-9\-]+\.)+[a-zA-Z0-9\-]+$

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IoConstants Class

• DefaultFileBufferSize: 4096

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ProcessConstants Class

Process and system constants.

Exit Codes

• ExitCodeSuccess: 0

Windows API Constants

• SW_RESTORE: 9
• SW_SHOW: 5
• SW_MINIMIZE: 6
• SW_MAXIMIZE: 3

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StorageConstants Class

Storage and CAS (Content-Addressable Storage) related constants.

CAS Retry Constants

Constant	Value	Description
MaxRetries	10	Maximum retry attempts for CAS operations
RetryDelayMs	100	Delay between retry attempts (ms)
MaxRetryDelayMs	5000	Maximum delay for exponential backoff (ms)

CAS Directory Structure

Constant	Value	Description
ObjectsDirectory	"objects"	Directory for CAS objects
LocksDirectory	"locks"	Directory for CAS locks

CAS Maintenance

• AutoGcIntervalDays: 1

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TimeIntervals Class

• UpdaterTimeout: 10 minutes
• DownloadTimeout: 30 minutes
• NotificationHideDelay: 3000ms

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Status Colors

• StatusSuccessColor: Color used to indicate success or positive status ("#4CAF50")
• StatusErrorColor: Color used to indicate error or negative status ("#F44336")

ValidationLimits

• DefaultWindowWidth: 1200
• DefaultWindowHeight: 800

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ValidationLimits Class

• MinConcurrentDownloads: 1
• MaxConcurrentDownloads: 10
• MinDownloadTimeoutSeconds: 30
• MaxDownloadTimeoutSeconds: 3600
• MinDownloadBufferSizeBytes: 4096
• MaxDownloadBufferSizeBytes: 1048576

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Usage Examples

Application Configuration

using GenHub.Core.Constants;

// Build user agent string
var userAgent = AppConstants.DefaultUserAgent; // "GenHub/1.0"

// Get application info
var appName = AppConstants.ApplicationName;
var version = AppConstants.Version;

Directory Operations

using GenHub.Core.Constants;

// Build standard directory paths
var dataPath = Path.Combine(basePath, DirectoryNames.Data);
var cachePath = Path.Combine(basePath, DirectoryNames.Cache);
var tempPath = Path.Combine(basePath, DirectoryNames.Temp);
var casPoolPath = Path.Combine(
    Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
    AppConstants.ApplicationName,
    DirectoryNames.CasPool);

File Type Validation

using GenHub.Core.Constants;

// Check file types
if (fileName.EndsWith(FileTypes.ManifestFileExtension))
{
    // Handle manifest file
}
else if (fileName.EndsWith(FileTypes.JsonFileExtension))
{
    // Handle JSON file
}

Manifest ID Operations

using GenHub.Core.Constants;

// Generate publisher content ID
var publisherId = $"{ManifestConstants.PublisherContentIdPrefix}.{contentName}.{ManifestConstants.DefaultManifestSchemaVersion}";

// Validate manifest ID length
if (manifestId.Length < ManifestConstants.MinManifestIdLength ||
    manifestId.Length > ManifestConstants.MaxManifestIdLength)
{
    throw new ArgumentException("Manifest ID length is invalid");
}

HTTP Operations with ApiConstants

using var client = new HttpClient();
client.DefaultRequestHeaders.UserAgent.ParseAdd(ApiConstants.DefaultUserAgent);

GitHub URL Validation

public bool IsGitHubUrl(string url)
{
    if (!Uri.TryCreate(url, UriKind.Absolute, out var uri))
        return false;

    return uri.Host.Equals(ApiConstants.GitHubDomain, StringComparison.OrdinalIgnoreCase);
}

Download Configuration

var downloadConfig = new DownloadConfiguration
{
    BufferSize = DownloadDefaults.BufferSizeBytes,
    MaxConcurrentDownloads = DownloadDefaults.MaxConcurrentDownloads,
    Timeout = TimeSpan.FromSeconds(DownloadDefaults.TimeoutSeconds),
    MaxRetryAttempts = DownloadDefaults.MaxRetryAttempts
};

CAS Operations

var retryCount = 0;
while (retryCount < StorageConstants.MaxRetries)
{
    try
    {
        // Perform CAS operation
        break;
    }
    catch (Exception)
    {
        retryCount++;
        await Task.Delay(StorageConstants.RetryDelayMs * retryCount);
    }
}

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UI Constants Example

var window = new Window
{
    Width = UiConstants.DefaultWindowWidth,
    Height = UiConstants.DefaultWindowHeight
};

// Using status colors for consistent UI theming
var successBrush = new SolidColorBrush(Color.Parse(UiConstants.StatusSuccessColor));
var errorBrush = new SolidColorBrush(Color.Parse(UiConstants.StatusErrorColor));

// Example XAML data binding with BoolToStatusColorConverter
// <TextBlock Text="Status" Foreground="{Binding IsActive, Converter={StaticResource BoolToStatusColorConverter}}" />

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Application Name Usage with AppConstants

// Using AppConstants.AppName for consistent application naming
var appDataPath = Path.Combine(
    Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
    AppConstants.AppName);

var userAgent = $"{AppConstants.AppName}/{AppConstants.AppVersion}";
// Result: "GenHub/1.0" (same as ApiConstants.DefaultUserAgent)

Validation with ValidationLimits

public bool ValidateConcurrentDownloads(int value)
{
    return value >= ValidationLimits.MinConcurrentDownloads &&
           value <= ValidationLimits.MaxConcurrentDownloads;
}

Time Intervals Usage

var updaterTimeout = TimeIntervals.UpdaterTimeout;
var downloadTimeout = TimeIntervals.DownloadTimeout;
var notificationDelay = TimeIntervals.NotificationHideDelay;

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Maintenance

When adding new constants:

1. Choose the appropriate constants file based on functionality
2. Follow naming conventions (PascalCase for constants)
3. Add comprehensive XML documentation
4. Update this documentation
5. Add tests for new constants
6. Ensure StyleCop compliance

Constants File Organization

• ApiConstants: Network and API-related constants
• AppConstants: Application-wide settings and metadata
• CasDefaults: Content-Addressable Storage defaults
• ConfigurationKeys: Configuration file keys and paths
• ConversionConstants: Unit conversion constants
• DirectoryNames: Standard directory naming conventions
• DownloadDefaults: Download operation defaults
• FileTypes: File extensions and naming patterns
• IoConstants: Input/output operation constants
• ManifestConstants: Manifest ID and validation constants
• ProcessConstants: System process and exit code constants
• StorageConstants: Storage and CAS operation constants
• TimeIntervals: Time spans and intervals
• UiConstants: User interface sizing and behavior
• ValidationLimits: Input validation boundaries

Best Practices

1. Centralization: All constants should be defined in the appropriate constants file
2. Documentation: Every constant should have XML documentation explaining its purpose
3. Testing: Constants should be tested for correctness and reasonable values
4. Consistency: Use constants instead of magic numbers or strings throughout the codebase
5. Naming: Use descriptive names that clearly indicate the constant's purpose
6. Grouping: Related constants should be grouped together within their respective files

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Related Documentation

• Manifest ID System
• Complete System Architecture