LanMountainDesktop/docs/LAUNCHER_COORDINATOR.md

Launcher Coordinator

LanMountainDesktop Launcher uses a per-user coordinator to prevent duplicate host startup.

Rules

• A Launcher reserves %LocalAppData%\LanMountainDesktop\.launcher\state\startup-attempt.json before starting the host.
• The active record stores coordinator pid, coordinator pipe name, heartbeat, host pid, Public IPC state, and shell status.
• Only the active coordinator may start the host process.
• Secondary Launchers attach to the coordinator and request desktop activation.
• A coordinator is considered live while its pid exists and its heartbeat is newer than 10s.
• Normal launch probes Host Public IPC first; if the host is already running, Launcher activates it and exits.

Tray And Taskbar

• Tray icon and tray menu are mandatory and are not controlled by user settings.
• Tray watchdog starts with the shell and runs until process exit.
• ShowInTaskbar=true affects only the main-window taskbar entry.
• When ShowInTaskbar=true, background mode uses a minimized taskbar entry while keeping tray visible.
• Pure TrayOnly is allowed only when ShowInTaskbar=false and tray is ready.

Public Shell IPC

Launcher and external callers can use:

• GetShellStatusAsync()
• ActivateMainWindowWithStatusAsync()
• EnsureTrayReadyAsync()
• EnsureTaskbarEntryAsync()

These APIs report process, shell, tray, taskbar, and activation state separately so callers do not infer health from window visibility alone.

Air APP Lifecycle

• LanMountainDesktop.AirAppRuntime is the Air APP lifecycle manager.
• The desktop host requests Air APP operations through IAirAppLifecycleService on the dedicated LanMountainDesktop.AirAppRuntime.v1 IPC pipe.
• Launcher pre-starts LanMountainDesktop.AirAppRuntime; when the dedicated pipe is unavailable, the desktop host starts the runtime directly and retries the request.
• AirApp Runtime, not Launcher, owns the Air APP lifecycle IPC host and AirAppHost process table.
• AirApp Runtime creates, activates, tracks, and closes Air APP host processes by instance key: {appId}:{sourceComponentId}:{sourcePlacementId}.
• LanMountainDesktop.AirAppHost registers itself with AirApp Runtime after its window opens and unregisters on close; Runtime also prunes exited processes.
• Launcher waits only for the desktop host startup path. AirApp Runtime remains alive while Launcher/Host/requester or any Air APP process is alive, then exits after all are gone.