refactor: move excalidraw-app outside src (#6987)

* refactor: move excalidraw-app outside src

* move some tests to excal app and fix some

* fix tests

* fix

* port remaining tests

* fix

* update snap

* move tests inside test folder

* fix

* fix

excalidraw-app/data/localStorage.ts

@@ -0,0 +1,115 @@
+import { ExcalidrawElement } from "../../src/element/types";
+import { AppState } from "../../src/types";
+import {
+  clearAppStateForLocalStorage,
+  getDefaultAppState,
+} from "../../src/appState";
+import { clearElementsForLocalStorage } from "../../src/element";
+import { STORAGE_KEYS } from "../app_constants";
+import { ImportedDataState } from "../../src/data/types";
+
+export const saveUsernameToLocalStorage = (username: string) => {
+  try {
+    localStorage.setItem(
+      STORAGE_KEYS.LOCAL_STORAGE_COLLAB,
+      JSON.stringify({ username }),
+    );
+  } catch (error: any) {
+    // Unable to access window.localStorage
+    console.error(error);
+  }
+};
+
+export const importUsernameFromLocalStorage = (): string | null => {
+  try {
+    const data = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_COLLAB);
+    if (data) {
+      return JSON.parse(data).username;
+    }
+  } catch (error: any) {
+    // Unable to access localStorage
+    console.error(error);
+  }
+
+  return null;
+};
+
+export const importFromLocalStorage = () => {
+  let savedElements = null;
+  let savedState = null;
+
+  try {
+    savedElements = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_ELEMENTS);
+    savedState = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_APP_STATE);
+  } catch (error: any) {
+    // Unable to access localStorage
+    console.error(error);
+  }
+
+  let elements: ExcalidrawElement[] = [];
+  if (savedElements) {
+    try {
+      elements = clearElementsForLocalStorage(JSON.parse(savedElements));
+    } catch (error: any) {
+      console.error(error);
+      // Do nothing because elements array is already empty
+    }
+  }
+
+  let appState = null;
+  if (savedState) {
+    try {
+      appState = {
+        ...getDefaultAppState(),
+        ...clearAppStateForLocalStorage(
+          JSON.parse(savedState) as Partial<AppState>,
+        ),
+      };
+    } catch (error: any) {
+      console.error(error);
+      // Do nothing because appState is already null
+    }
+  }
+  return { elements, appState };
+};
+
+export const getElementsStorageSize = () => {
+  try {
+    const elements = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_ELEMENTS);
+    const elementsSize = elements?.length || 0;
+    return elementsSize;
+  } catch (error: any) {
+    console.error(error);
+    return 0;
+  }
+};
+
+export const getTotalStorageSize = () => {
+  try {
+    const appState = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_APP_STATE);
+    const collab = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_COLLAB);
+    const library = localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_LIBRARY);
+
+    const appStateSize = appState?.length || 0;
+    const collabSize = collab?.length || 0;
+    const librarySize = library?.length || 0;
+
+    return appStateSize + collabSize + librarySize + getElementsStorageSize();
+  } catch (error: any) {
+    console.error(error);
+    return 0;
+  }
+};
+
+export const getLibraryItemsFromStorage = () => {
+  try {
+    const libraryItems: ImportedDataState["libraryItems"] = JSON.parse(
+      localStorage.getItem(STORAGE_KEYS.LOCAL_STORAGE_LIBRARY) as string,
+    );
+
+    return libraryItems || [];
+  } catch (error) {
+    console.error(error);
+    return [];
+  }
+};