feat(charts): manage investigation charts in a scrolling workspace

src/shared/ui/floating-window-layer.ts

@@ -1,23 +1,58 @@
 let order: string[] = [];
 const listeners = new Set<() => void>();
 let host: HTMLDivElement | undefined;
+export type FloatingWindowEntry = { id: string; title: string; focus: () => void; close: () => void };
+const registered = new Map<string, {
+  entry: FloatingWindowEntry;
+  actions: Pick<FloatingWindowEntry, "focus" | "close">;
+}>();
+let entries: readonly FloatingWindowEntry[] = [];
+
+function publishWindows() {
+  entries = order.flatMap((id) => {
+    const record = registered.get(id);
+    return record ? [record.entry] : [];
+  });
+  listeners.forEach((listener) => listener());
+}
 
 export const floatingWindowOrder = () => order;
+/** Stable between changes, ordered from the back window to the foreground. */
+export const floatingWindowEntries = () => entries;
 export const subscribeFloatingWindows = (listener: () => void) => {
   listeners.add(listener);
   return () => { listeners.delete(listener); };
 };
 
+export function registerFloatingWindow(entry: FloatingWindowEntry) {
+  const previous = registered.get(entry.id);
+  if (previous) {
+    // Callbacks can change without invalidating the subscribed presentation.
+    previous.actions.focus = entry.focus;
+    previous.actions.close = entry.close;
+    if (previous.entry.title === entry.title) return;
+    previous.entry = { ...previous.entry, title: entry.title };
+  } else {
+    const actions = { focus: entry.focus, close: entry.close };
+    registered.set(entry.id, { actions, entry: { id: entry.id, title: entry.title,
+      focus: () => { if (registered.get(entry.id)?.actions === actions) actions.focus(); },
+      close: () => { if (registered.get(entry.id)?.actions === actions) actions.close(); } } });
+    if (!order.includes(entry.id)) order = [...order, entry.id];
+  }
+  publishWindows();
+}
+
 export function raiseFloatingWindow(id: string) {
   if (order.at(-1) === id) return;
   order = [...order.filter((item) => item !== id), id];
-  listeners.forEach((listener) => listener());
+  publishWindows();
 }
 
 export function removeFloatingWindow(id: string) {
-  if (!order.includes(id)) return;
+  if (!order.includes(id) && !registered.has(id)) return;
+  registered.delete(id);
   order = order.filter((item) => item !== id);
-  listeners.forEach((listener) => listener());
+  publishWindows();
 }
 
 export function floatingWindowHost() {