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The Core library provides the foundation for Zeal’s operation, managing the application lifecycle, configuration, file operations, and local HTTP serving.

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Core::Application

The Application class is the central hub of Zeal, implemented as a singleton that coordinates all major components. Location: src/libs/core/application.h

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Key Responsibilities

  • Application lifecycle management
  • Component initialization and coordination
  • Network request handling
  • Update checking
  • Docset extraction orchestration

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Public Interface

class Application final : public QObject
{
public:
    static Application *instance();
    
    WidgetUi::MainWindow *mainWindow() const;
    QNetworkAccessManager *networkManager() const;
    Settings *settings() const;
    Registry::DocsetRegistry *docsetRegistry();
    FileManager *fileManager() const;
    HttpServer *httpServer() const;
    
    static QString cacheLocation();
    static QString configLocation();
    static QVersionNumber version();
    
public slots:
    void executeQuery(const Registry::SearchQuery &query, bool preventActivation);
    void extract(const QString &filePath, const QString &destination, const QString &root);
    QNetworkReply *download(const QUrl &url);
    void checkForUpdates(bool quiet = false);
    
signals:
    void extractionCompleted(const QString &filePath);
    void extractionError(const QString &filePath, const QString &errorString);
    void extractionProgress(const QString &filePath, qint64 extracted, qint64 total);
    void updateCheckDone(const QString &version);
    void updateCheckError(const QString &message);
};

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Member Components

From src/libs/core/application.h:79-91: 
Settings *m_settings = nullptr;
QNetworkAccessManager *m_networkManager = nullptr;
FileManager *m_fileManager = nullptr;
HttpServer *m_httpServer = nullptr;
QThread *m_extractorThread = nullptr;
Extractor *m_extractor = nullptr;
Registry::DocsetRegistry *m_docsetRegistry = nullptr;
WidgetUi::MainWindow *m_mainWindow = nullptr;

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Core::Settings

Manages all application configuration with automatic persistence. Location: src/libs/core/settings.h

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Configuration Categories

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Startup Settings

bool startMinimized;
bool checkForUpdate;
bool hideMenuBar;

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System Tray

bool showSystrayIcon;
bool minimizeToSystray;
bool hideOnClose;

bool isFuzzySearchEnabled;

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Content Appearance

enum class ContentAppearance {
    Automatic = 0,
    Light,
    Dark
};

ContentAppearance contentAppearance;
QString customCssFile;
bool isSmoothScrollingEnabled;
bool isHighlightOnNavigateEnabled;

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Font Configuration

QString defaultFontFamily;
QString serifFontFamily;
QString sansSerifFontFamily;
QString fixedFontFamily;
int defaultFontSize;
int defaultFixedFontSize;
int minimumFontSize;

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Network Proxy

enum ProxyType {
    None = 0,
    System = 1,
    Http = 3,
    Socks5 = 4
};

ProxyType proxyType;
QString proxyHost;
quint16 proxyPort;
bool proxyAuthenticate;
QString proxyUserName;
QString proxyPassword;

enum class ExternalLinkPolicy {
    Ask = 0,
    Open,
    OpenInSystemBrowser
};

ExternalLinkPolicy externalLinkPolicy;

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Methods

void load();  // Load settings from persistent storage
void save();  // Save settings to persistent storage
bool isDarkModeEnabled() const;
static ColorScheme colorScheme();

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Signals

signals:
    void updated();  // Emitted when settings are modified
Settings are persisted using Qt’s QSettings mechanism and stored in platform-specific locations.

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Core::HttpServer

Provides a local HTTP server for serving documentation files efficiently. Location: src/libs/core/httpserver.h

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Purpose

The HTTP server enables:
  • Local serving of documentation files without file:// protocol limitations
  • Proper handling of web resources and AJAX requests
  • Support for JavaScript-heavy documentation

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Interface

class HttpServer : public QObject
{
public:
    explicit HttpServer(QObject *parent = nullptr);
    
    QUrl baseUrl() const;
    QUrl mount(const QString &prefix, const QString &path);
    bool unmount(const QString &prefix);
};

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Implementation Details

From src/libs/core/httpserver.h:36-39: 
std::unique_ptr<httplib::Server> m_server;
std::future<bool> m_future;
QUrl m_baseUrl;
The server uses the httplib library and runs asynchronously using std::future to avoid blocking the main thread.

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Core::FileManager

Simple utility for file system operations. Location: src/libs/core/filemanager.h 
class FileManager final : public QObject
{
public:
    explicit FileManager(QObject *parent = nullptr);
    bool removeRecursively(const QString &path);
};
Provides safe recursive directory removal for docset uninstallation.

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Core::Extractor

Handles archive extraction for docset installation. Location: src/libs/core/extractor.h

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Interface

class Extractor final : public QObject
{
public slots:
    void extract(const QString &sourceFile,
                 const QString &destination,
                 const QString &root = QString());

signals:
    void error(const QString &filePath, const QString &message);
    void completed(const QString &filePath);
    void progress(const QString &filePath, qint64 extracted, qint64 total);
};

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Threading

The extractor runs in a dedicated thread (see Application::m_extractorThread) to prevent UI blocking during large archive extraction. Progress is reported through Qt signals.

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Archive Support

Uses libarchive (see struct archive at line 9) to support multiple archive formats including:
  • tar.gz
  • tar.bz2
  • zip
  • And other formats supported by libarchive

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Component Initialization Flow

  1. Application constructor creates core services:
    • Settings - loads configuration
    • NetworkManager - sets up HTTP client
    • FileManager - prepares file operations
    • HttpServer - starts local server
    • Extractor - creates extraction thread
  2. DocsetRegistry is initialized with storage path from settings
  3. MainWindow is created and connected to application signals
  4. Settings are applied through applySettings() slot

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See Also

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