feat(web): cleanup of variable stores

This addresses code review comments in #15437 and removes some
unnecessary definitions related to variable stores. It keeps the
`VariableStoreSerializer` interface although currently
`VariableStoreCookieSerializer` is the only implementation. Conceptually
IMO it makes sense to use a more abstract interface so that in the future
for example we could easily use a different store for a node
implementation.

Details of this change:
- remove `VariableStoreDictionary` interface and replace with
  `VariableStore` type
- remove `VarStoreSerializer` class and replace with
  ` CookieSerializer<VariableStore>`

Follow-up-of: #15437
Test-bot: skip

web/src/engine/src/js-processor/jsKeyboardInterface.ts

@@ -22,7 +22,6 @@ import {
   type KeyEvent,
   type TextStore,
   VariableStore,
-  VariableStoreDictionary,
   VariableStoreSerializer,
 } from "keyman/engine/keyboard";
 import { PlatformSystemStore } from './platformSystemStore.js';
@@ -1103,7 +1102,7 @@ export class JSKeyboardInterface extends KeyboardHarness {
    * @param stores A dictionary of stores which should be found in the
    *               keyboard
    */
-  applyVariableStores(stores: VariableStoreDictionary): void {
+  applyVariableStores(stores: VariableStore): void {
     this.activeKeyboard.variableStores = stores;
   }
 

web/src/engine/src/keyboard/index.ts

@@ -30,7 +30,7 @@ export { EmulationKeystrokes, LogMessages, DefaultRules } from "./defaultRules.j
 export { type KeyDistribution, KeyEventSpec, KeyEvent } from "./keyEvent.js";
 export { KeyMapping } from "./keyMapping.js";
 export { type SystemStoreMutationHandler, MutableSystemStore, SystemStore, SystemStoreIDs, type SystemStoreDictionary } from "./systemStore.js";
-export { type VariableStore, VariableStoreSerializer, VariableStoreDictionary } from "./variableStore.js";
+export { type VariableStore, VariableStoreSerializer } from "./variableStore.js";
 
 export { DOMKeyboardLoader } from './keyboards/loaders/domKeyboardLoader.js';
 export { SyntheticTextStore } from "./syntheticTextStore.js";

web/src/engine/src/keyboard/keyboards/jsKeyboard.ts

@@ -4,7 +4,7 @@ import { ActiveKey, ActiveLayout, ActiveSubKey } from "./activeLayout.js";
 import { KeyEvent } from "../keyEvent.js";
 import { type TextStore } from "../textStore.js";
 import { KeymanWebKeyboard, ModifierKeyConstants, TouchLayout } from "@keymanapp/common-types";
-import { VariableStoreDictionary } from "../variableStore.js";
+import { VariableStore } from "../variableStore.js";
 
 import ComplexKeyboardStore = KeymanWebKeyboard.ComplexKeyboardStore;
 import KeyboardObject = KeymanWebKeyboard.KeyboardObject;
@@ -120,9 +120,9 @@ export class JSKeyboard {
    *
    * @returns an object with each property referencing a variable store
    */
-  get variableStores(): VariableStoreDictionary {
+  get variableStores(): VariableStore {
     const storeNames = this.scriptObject['KVS'];
-    let values: VariableStoreDictionary = {};
+    let values: VariableStore = {};
     if(Array.isArray(storeNames)) {
       for(let store of storeNames) {
         values[store] = this.scriptObject[store];
@@ -139,7 +139,7 @@ export class JSKeyboard {
    *
    * @param values  name-value pairs for each store value
    */
-  set variableStores(values: VariableStoreDictionary) {
+  set variableStores(values: VariableStore) {
     const storeNames = this.scriptObject['KVS'];
     if(Array.isArray(storeNames)) {
       for(let store of storeNames) {

web/src/engine/src/keyboard/keyboards/processorAction.ts

@@ -3,7 +3,7 @@
  */
 import { LexicalModelTypes } from '@keymanapp/common-types';
 import { Transcription } from './transcription.js';
-import { VariableStore, VariableStoreDictionary } from '../variableStore.js';
+import { VariableStore } from '../variableStore.js';
 import { SystemStoreDictionary } from '../systemStore.js';
 
 /**
@@ -34,7 +34,7 @@ export class ProcessorAction {
   /**
    * A set of variable stores with possible changes to be applied during finalization.
    */
-  variableStores: VariableStoreDictionary = {};
+  variableStores: VariableStore = {};
 
   /**
    * Denotes a non-output default behavior; this should be evaluated later, against the true keystroke.

web/src/engine/src/keyboard/variableStore.ts

@@ -4,10 +4,6 @@
  * Definitions for variable stores (see kmn reference)
  */
 
-export interface VariableStoreDictionary {
-  [name: string]: string;
-};
-
 export type VariableStore = { [name: string]: string; };
 
 export interface VariableStoreSerializer {

web/src/engine/src/main/variableStoreCookieSerializer.ts

@@ -8,42 +8,20 @@ import { CookieSerializer } from "keyman/engine/dom-utils";
 // Also of note:  there's nothing we can do to allow TS to provide type-checking of
 // dynamic property names; they'd have to be known at compile time to facilitate
 // strict type checking.
-class VarStoreSerializer extends CookieSerializer<VariableStore> {
-  public constructor(keyboardID: string, storeName: string) {
-    super(`KeymanWeb_${keyboardID}_Option_${storeName}`);
-  }
-
-  public load(): VariableStore {
-    return super.load(decodeURIComponent);
-  }
-
-  public save(storeMap: VariableStore) {
-    super.save(storeMap, encodeURIComponent);
-  }
-
-  /**
-   * Find all variable stores associated with a given keyboard.
-   *
-   * @param {string}  keyboardID  The keyboard ID whose variable stores are to be found.
-   *
-   * @returns An array of VariableStore objects found for the keyboard.
-   */
-  public static findStores(keyboardID: string): VariableStore[] {
-    const pattern = new RegExp(`^KeymanWeb_${keyboardID}_Option_`);
-    const matching = CookieSerializer.loadAllMatching<VariableStore>(pattern, decodeURIComponent);
-    return matching.map(m => m.value);
-  }
-}
 
 export class VariableStoreCookieSerializer implements VariableStoreSerializer {
+  private getStoreCookieName(keyboardID: string, storeName: string): string {
+    return `KeymanWeb_${keyboardID}_Option_${storeName}`;
+  }
+
   public loadStore(keyboardID: string, storeName: string): VariableStore {
-    const storeCookieSerializer = new VarStoreSerializer(keyboardID, storeName);
-    return storeCookieSerializer.load();
+    const storeCookieSerializer = new CookieSerializer<VariableStore>(this.getStoreCookieName(keyboardID, storeName));
+    return storeCookieSerializer.load(decodeURIComponent);
   }
 
   public saveStore(keyboardID: string, storeName: string, storeMap: VariableStore) {
-    const storeCookieSerializer = new VarStoreSerializer(keyboardID, storeName);
-    storeCookieSerializer.save(storeMap);
+    const storeCookieSerializer = new CookieSerializer<VariableStore>(this.getStoreCookieName(keyboardID, storeName));
+    storeCookieSerializer.save(storeMap, encodeURIComponent);
   }
 
   /**
@@ -54,6 +32,8 @@ export class VariableStoreCookieSerializer implements VariableStoreSerializer {
    * @returns An array of VariableStore objects found for the keyboard.
    */
   public findStores(keyboardID: string): VariableStore[] {
-    return VarStoreSerializer.findStores(keyboardID);
+    const pattern = new RegExp(`^${this.getStoreCookieName(keyboardID, '')}`);
+    const matching = CookieSerializer.loadAllMatching<VariableStore>(pattern, decodeURIComponent);
+    return matching.map(m => m.value);
   }
 }