feat(editor): add table structure peek and dblclick insert

apps/desktop/src/lib/editor/focusedQueryEditorView.ts

@@ -0,0 +1,71 @@
+import { EditorView } from "@codemirror/view";
+import type { DatabaseType } from "@/types/database";
+
+export const QUERY_EDITOR_ROOT_SELECTOR = "[data-query-editor-root]";
+export const STRUCTURE_PEEK_PANEL_SELECTOR = "[data-structure-peek-panel]";
+
+/** Dialect / connection metadata for inserting into a specific query editor view. */
+export interface QueryEditorInsertContext {
+  connectionId?: string;
+  database?: string;
+  schema?: string;
+  databaseType?: DatabaseType;
+}
+
+let lastFocusedQueryEditorView: EditorView | null = null;
+const insertContextByView = new WeakMap<EditorView, QueryEditorInsertContext>();
+
+export function rememberFocusedQueryEditorView(view: EditorView | null | undefined): void {
+  if (view) lastFocusedQueryEditorView = view;
+}
+
+/** Clear the remembered view when it is destroyed (or clear unconditionally). */
+export function clearRememberedFocusedQueryEditorView(view?: EditorView | null): void {
+  if (view == null || lastFocusedQueryEditorView === view) {
+    lastFocusedQueryEditorView = null;
+  }
+}
+
+export function registerQueryEditorInsertContext(view: EditorView, context: QueryEditorInsertContext): void {
+  insertContextByView.set(view, context);
+}
+
+export function unregisterQueryEditorInsertContext(view: EditorView): void {
+  insertContextByView.delete(view);
+}
+
+export function queryEditorInsertContext(view: EditorView): QueryEditorInsertContext | undefined {
+  return insertContextByView.get(view);
+}
+
+/**
+ * Resolve the CodeMirror view that should receive peek inserts.
+ * - Focus inside a query editor → that view (must still report hasFocus).
+ * - Focus inside a structure peek panel → most recently focused query editor.
+ * - Focus elsewhere (sidebar, etc.) → null.
+ */
+export function focusedQueryEditorView(active: Element | null = typeof document !== "undefined" ? document.activeElement : null): EditorView | null {
+  if (!(active instanceof Element)) return null;
+
+  const root = active.closest(QUERY_EDITOR_ROOT_SELECTOR);
+  if (root instanceof HTMLElement) {
+    const view = EditorView.findFromDOM(root);
+    if (!view?.hasFocus) return null;
+    rememberFocusedQueryEditorView(view);
+    return view;
+  }
+
+  if (active.closest(STRUCTURE_PEEK_PANEL_SELECTOR)) {
+    const remembered = lastFocusedQueryEditorView;
+    if (remembered?.dom.isConnected) return remembered;
+    return null;
+  }
+
+  return null;
+}
+
+/** Keep editor focus when interacting with non-editable peek chrome (palette-style). */
+export function shouldPreserveEditorFocusOnPeekPointerDown(target: EventTarget | null): boolean {
+  if (!(target instanceof Element)) return false;
+  return !target.closest("input, textarea, button, select, a, [contenteditable='true']");
+}