feat: Element locking (#4964)

Co-authored-by: dwelle <luzar.david@gmail.com>
Co-authored-by: Zsolt Viczian <viczian.zsolt@gmail.com>

src/actions/actionToggleLock.ts

@@ -0,0 +1,63 @@
+import { newElementWith } from "../element/mutateElement";
+import { ExcalidrawElement } from "../element/types";
+import { KEYS } from "../keys";
+import { getSelectedElements } from "../scene";
+import { arrayToMap } from "../utils";
+import { register } from "./register";
+
+export const actionToggleLock = register({
+  name: "toggleLock",
+  trackEvent: { category: "element" },
+  perform: (elements, appState) => {
+    const selectedElements = getSelectedElements(elements, appState, true);
+
+    if (!selectedElements.length) {
+      return false;
+    }
+
+    const operation = getOperation(selectedElements);
+    const selectedElementsMap = arrayToMap(selectedElements);
+
+    return {
+      elements: elements.map((element) => {
+        if (!selectedElementsMap.has(element.id)) {
+          return element;
+        }
+
+        return newElementWith(element, { locked: operation === "lock" });
+      }),
+      appState,
+      commitToHistory: true,
+    };
+  },
+  contextItemLabel: (elements, appState) => {
+    const selected = getSelectedElements(elements, appState, false);
+    if (selected.length === 1) {
+      return selected[0].locked
+        ? "labels.elementLock.unlock"
+        : "labels.elementLock.lock";
+    }
+
+    if (selected.length > 1) {
+      return getOperation(selected) === "lock"
+        ? "labels.elementLock.lockAll"
+        : "labels.elementLock.unlockAll";
+    }
+
+    throw new Error(
+      "Unexpected zero elements to lock/unlock. This should never happen.",
+    );
+  },
+  keyTest: (event, appState, elements) => {
+    return (
+      event.key.toLocaleLowerCase() === KEYS.L &&
+      event[KEYS.CTRL_OR_CMD] &&
+      event.shiftKey &&
+      getSelectedElements(elements, appState, false).length > 0
+    );
+  },
+});
+
+const getOperation = (
+  elements: readonly ExcalidrawElement[],
+): "lock" | "unlock" => (elements.some((el) => !el.locked) ? "lock" : "unlock");