Broiler.Hosting.Linux 0.1.0-preview.3

Broiler.Hosting

Shared desktop and mobile hosting runtime, windowing services, input fidelity, and platform integration for the Broiler application suite (Broiler.Mail, Broiler.Code, Broiler.Writer, Broiler.Browser).

Components

Broiler.Hosting.Windows

Provides Windows desktop hosting facilities:

• WindowsClipboard: Hardened Win32 clipboard integration with 1 MB UTF-16 bounds protection, strict GlobalSize validation, direct or lazy HWND owner resolution, and safe OS memory handoff.
• WindowsWindowSizing: Window sizing, minimum dimension enforcement (DPI-scaled client minimum 640x480) via WM_GETMINMAXINFO, and dynamic multi-monitor DPI transition handling via WM_DPICHANGED.
• WindowsTheme: System appearance inspection querying dark/light preference, Windows high contrast mode (SPI_GETHIGHCONTRAST), reduced motion preferences (SPI_GETCLIENTAREAANIMATION), and the "Make text bigger" text scale (TextScaleFactor, 1.0 to 2.25), exposing UiSystemSettings. ResolveTheme(UiSystemSettings) returns the standard preset, or in high contrast a palette built from the user's actual system colors (WindowsSystemColors, CreateHighContrastTheme), with readable fallbacks for a focus ring or link color that blends into the window background.
• WindowsTitleBar: Matches the native caption to a dark or light palette (DWMWA_USE_IMMERSIVE_DARK_MODE, Windows 10 build 19041 or later). Call it after the native window exists and whenever the palette changes.
• WindowsInputBridge: High-fidelity native input and scroll integration:
  • Top-level window activation focus handoff (WM_SETFOCUS and WM_ACTIVATE transferring Win32 focus to the render child HWND).
  • Exactly-once text delivery across WM_CHAR and IMM32 IME compositions (WM_IME_STARTCOMPOSITION, WM_IME_COMPOSITION, synthetic WM_CHAR suppression after commit).
  • Surrogate pair assembly (\uD83D\uDE00) and stray surrogate cleanup.
  • Shortcut modifier isolation (Ctrl+C, Ctrl+A, Ctrl+V, Ctrl+Z, Ctrl+Backspace, Ctrl+Enter suppressed from text generation) with full AltGr support.
  • Sub-notch precision mouse wheel and horizontal tilt wheel handling (WM_MOUSEWHEEL, WM_MOUSEHWHEEL).
  • Decoupled application-level input filtering hook (Func<UiInputEvent, bool>?).
• WindowsAutomationBridge & WindowsElementAutomationPeer: Native Windows UI Automation (UIA) bridge:
  • Implements IRawElementProviderFragmentRoot, IRawElementProviderFragment, IRawElementProviderSimple.
  • Maps Broiler UI controls to standard UIA patterns (IInvokeProvider, IValueProvider, ISelectionProvider, ISelectionItemProvider, IToggleProvider, IExpandCollapseProvider, IScrollItemProvider, and ITextProvider/ITextRangeProvider for Edit and RichEdit text, by character, word, paragraph, and document, with search and selection; never for password fields).
  • Names come from the semantic name, never a type name; a field targeted by a label is named by that label and reports it as LabeledBy, with its text as Value and its placeholder as HelpText. Unnamed layout containers are non-control elements, so the Control view shows their children directly.
  • Only the selected tab's content is exposed: inactive tab content is skipped in navigation and hit-testing and reported offscreen.
  • Change events are raised only for real differences (name, enabled state, value and text, text selection, list or tab selection).
  • Create the bridge with the handle of an existing window: with a Direct2DWindow, in OnCreated. A zero handle attaches nothing and clients see an empty pane. The same applies to WindowsInputBridge.
  • Coordinate-free control and item tree navigation.
  • Password protection ensuring sensitive fields never expose plain text through UIA.
  • Point hit-testing down to child elements and virtualized list items.
  • Dynamic peer lifecycle management and live region status announcements.

Broiler.Hosting.Linux

Provides Linux desktop hosting facilities:

• LinuxUiHost: Reusable IUiHost implementation adapting IBroilerRenderer and IBroilerSurface to Broiler UI sessions, tracking viewport dimensions, DPI scale, frame indexing, and invalidations without double-scaling.
• LinuxX11Clipboard: Hardened X11 clipboard and primary selection host (IUiClipboardHost, IDisposable) with 1 MB payload limits, INCR streaming, UTF-8/Latin-1 conversion, timeout bounds, and safe non-Linux execution guards.
• LinuxBackendDiagnostics: Preflight verification for X11/EGL/OpenGL dependencies (libEGL.so.1, libGL.so.1, libOpenGL.so.0, libX11.so.6, DISPLAY, architecture).
• LinuxInputCoordinator & LinuxInputSnapshot: Evdev input stream coordination unifying keyboard and mouse devices, merging modifier keys across separate evdev nodes, pointer clamping, and non-blocking event dispatch.

Broiler.Hosting.Android

Provides Android hosting facilities with multi-targeting support (net10.0 for headless testing and net10.0-android36.0 for full runtime integration):

• AndroidUiHost: Reusable IUiHost, IUiClipboardHost, and IUiTextInputHost adapter supporting AndroidBroilerView, direct delegates, or headless surface/renderer.
• AndroidBackendDiagnostics: Preflight check for Android runtime, architecture, and native graphic libraries (libEGL.so, libGLESv3.so, libandroid.so), with safe degradation on non-Android hosts.
• AndroidBroilerView: Hardware-accelerated SurfaceView with Choreographer vsync loop, device lost recovery, density/viewport tracking, touch/hover/key routing, IME lifecycle, and clipboard glue.
• AndroidCanvasRenderer: Hardware-accelerated IBroilerRenderer replaying display lists onto Android Canvas and Paint with typeface caching.
• AndroidInputCoordinator: Unified coordinator routing touch contacts, pen contacts, key events, and IME text events into UiInputEvents.
• AndroidInsetLayout: FrameLayout handling display cutouts, navigation bars, and status bar insets.
• BroilerInputConnection: BaseInputConnection bridging Android IME to AndroidTextInputDevice.

Architecture & Dependency Separation

Broiler.Hosting follows strict unidirectional dependency layering:

UI Abstractions + Graphics + Native Platform
                   │
                   ▼
       Broiler.Hosting.<Platform>
                   │
                   ▼
  Consumer Heads (Mail, Code, Writer, Browser)

Application-specific concerns (close/save guards, draft persistence, credential vaults, application commands) remain strictly outside the hosting component in the respective application layers.

Testing

dotnet test Broiler.Hosting.slnx

All unit tests in tests/Broiler.Hosting.Windows.Tests, tests/Broiler.Hosting.Linux.Tests, and tests/Broiler.Hosting.Android.Tests run headlessly and validate clipboard safety, sizing/DPI, system theme queries, input fidelity, backend diagnostics, and accessibility trees across platforms.