let modeVersion = 0;
let currentInitId = null;
const setModeDebounced = debounce((m) => setMode(m), 150); Unique instance IDs: viewerframe mode refresh hot
function setModeAsync(mode) { const v = ++modeVersion; return doAsyncSetup(mode).then(result => { if (v !== modeVersion) return; // ignore stale applyMode(result); }); } Debounce/coalesce:
// prepare resources await prepareResourcesFor(mode); if (currentInitId !== initId) return; // stale, abort let modeVersion = 0; let currentInitId = null;
// finalize finalizeModeActivation(instanceId, mode); } Subscription cleanup:
async function activateMode(instanceId, mode) { const initId = Symbol(); currentInitId = initId; let modeVersion = 0
function mountViewer() { const unsub = eventBus.subscribe('mode-change', handler); onUnmount(() => unsub()); } Versioned async operations: