Refactor to add readonly interfaces

Using more granular interfaces adds to expressiveness of the code.
Knowing what needs to mutate the state explicitly helps easier
understanding of the code and therefore increases the maintainability.

src/application/Context/IApplicationContext.ts

@@ -1,12 +1,16 @@
-import { ICategoryCollectionState } from './State/ICategoryCollectionState';
+import { ICategoryCollectionState, IReadOnlyCategoryCollectionState } from './State/ICategoryCollectionState';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 import { IEventSource } from '@/infrastructure/Events/IEventSource';
 import { IApplication } from '@/domain/IApplication';
 
-export interface IApplicationContext {
+export interface IReadOnlyApplicationContext {
     readonly app: IApplication;
-    readonly state: ICategoryCollectionState;
+    readonly state: IReadOnlyCategoryCollectionState;
     readonly contextChanged: IEventSource<IApplicationContextChangedEvent>;
+}
+
+export interface IApplicationContext extends IReadOnlyApplicationContext {
+    readonly state: ICategoryCollectionState;
     changeContext(os: OperatingSystem): void;
 }
 

src/application/Context/State/CategoryCollectionState.ts

@@ -5,7 +5,7 @@ import { UserSelection } from './Selection/UserSelection';
 import { IUserSelection } from './Selection/IUserSelection';
 import { ICategoryCollectionState } from './ICategoryCollectionState';
 import { IApplicationCode } from './Code/IApplicationCode';
-import { ICategoryCollection } from '../../../domain/ICategoryCollection';
+import { ICategoryCollection } from '@/domain/ICategoryCollection';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 
 export class CategoryCollectionState implements ICategoryCollectionState {

src/application/Context/State/Code/ApplicationCode.ts

@@ -2,7 +2,7 @@ import { CodeChangedEvent } from './Event/CodeChangedEvent';
 import { CodePosition } from './Position/CodePosition';
 import { ICodeChangedEvent } from './Event/ICodeChangedEvent';
 import { SelectedScript } from '@/application/Context/State/Selection/SelectedScript';
-import { IUserSelection } from '@/application/Context/State/Selection/IUserSelection';
+import { IReadOnlyUserSelection } from '@/application/Context/State/Selection/IUserSelection';
 import { UserScriptGenerator } from './Generation/UserScriptGenerator';
 import { EventSource } from '@/infrastructure/Events/EventSource';
 import { IApplicationCode } from './IApplicationCode';
@@ -16,7 +16,7 @@ export class ApplicationCode implements IApplicationCode {
     private scriptPositions = new Map<SelectedScript, CodePosition>();
 
     constructor(
-        userSelection: IUserSelection,
+        userSelection: IReadOnlyUserSelection,
         private readonly scriptingDefinition: IScriptingDefinition,
         private readonly generator: IUserScriptGenerator = new UserScriptGenerator()) {
         if (!userSelection) { throw new Error('userSelection is null or undefined'); }

src/application/Context/State/Filter/IUserFilter.ts

@@ -1,10 +1,13 @@
 import { IEventSource } from '@/infrastructure/Events/IEventSource';
 import { IFilterResult } from './IFilterResult';
 
-export interface IUserFilter {
+export interface IReadOnlyUserFilter {
     readonly currentFilter: IFilterResult | undefined;
     readonly filtered: IEventSource<IFilterResult>;
     readonly filterRemoved: IEventSource<void>;
+}
+
+export interface IUserFilter extends IReadOnlyUserFilter {
     setFilter(filter: string): void;
     removeFilter(): void;
 }

src/application/Context/State/ICategoryCollectionState.ts

@@ -1,13 +1,18 @@
-import { IUserFilter } from './Filter/IUserFilter';
-import { IUserSelection } from './Selection/IUserSelection';
+import { IReadOnlyUserFilter, IUserFilter } from './Filter/IUserFilter';
+import { IReadOnlyUserSelection, IUserSelection } from './Selection/IUserSelection';
 import { IApplicationCode } from './Code/IApplicationCode';
 import { ICategoryCollection } from '@/domain/ICategoryCollection';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 
-export interface ICategoryCollectionState {
+export interface IReadOnlyCategoryCollectionState {
     readonly code: IApplicationCode;
+    readonly os: OperatingSystem;
+    readonly filter: IReadOnlyUserFilter;
+    readonly selection: IReadOnlyUserSelection;
+    readonly collection: ICategoryCollection;
+}
+
+export interface ICategoryCollectionState extends IReadOnlyCategoryCollectionState {
     readonly filter: IUserFilter;
     readonly selection: IUserSelection;
-    readonly collection: ICategoryCollection;
-    readonly os: OperatingSystem;
 }

src/application/Context/State/Selection/IUserSelection.ts

@@ -3,18 +3,21 @@ import { IScript } from '@/domain/IScript';
 import { ICategory } from '@/domain/ICategory';
 import { IEventSource } from '@/infrastructure/Events/IEventSource';
 
-export interface IUserSelection {
+export interface IReadOnlyUserSelection {
     readonly changed: IEventSource<ReadonlyArray<SelectedScript>>;
     readonly selectedScripts: ReadonlyArray<SelectedScript>;
+    isSelected(scriptId: string): boolean;
     areAllSelected(category: ICategory): boolean;
     isAnySelected(category: ICategory): boolean;
+}
+
+export interface IUserSelection extends IReadOnlyUserSelection {
     removeAllInCategory(categoryId: number): void;
     addOrUpdateAllInCategory(categoryId: number, revert: boolean): void;
     addSelectedScript(scriptId: string, revert: boolean): void;
     addOrUpdateSelectedScript(scriptId: string, revert: boolean): void;
     removeSelectedScript(scriptId: string): void;
     selectOnly(scripts: ReadonlyArray<IScript>): void;
-    isSelected(scriptId: string): boolean;
     selectAll(): void;
     deselectAll(): void;
 }

src/presentation/components/Code/CodeButtons/TheCodeButtons.vue

@@ -32,13 +32,13 @@ import Dialog from '@/presentation/components/Shared/Dialog.vue';
 import IconButton from './IconButton.vue';
 import MacOsInstructions from './MacOsInstructions.vue';
 import { Environment } from '@/application/Environment/Environment';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { ScriptingLanguage } from '@/domain/ScriptingLanguage';
 import { IApplicationCode } from '@/application/Context/State/Code/IApplicationCode';
 import { IScriptingDefinition } from '@/domain/IScriptingDefinition';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 import { CodeRunner } from '@/infrastructure/CodeRunner';
-import { IApplicationContext } from '@/application/Context/IApplicationContext';
+import { IReadOnlyApplicationContext } from '@/application/Context/IApplicationContext';
 
 @Component({
   components: {
@@ -70,7 +70,7 @@ export default class TheCodeButtons extends StatefulVue {
     await executeCode(context);
   }
 
-  protected handleCollectionState(newState: ICategoryCollectionState): void {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
     this.canRun = this.isDesktopVersion && newState.collection.os === Environment.CurrentEnvironment.os;
     this.isMacOsCollection = newState.collection.os === OperatingSystem.macOS;
     this.fileName = buildFileName(newState.collection.scripting);
@@ -91,7 +91,7 @@ export default class TheCodeButtons extends StatefulVue {
   }
 }
 
-function saveCode(fileName: string, state: ICategoryCollectionState) {
+function saveCode(fileName: string, state: IReadOnlyCategoryCollectionState) {
   const content = state.code.current;
   const type = getType(state.collection.scripting.language);
   SaveFileDialog.saveFile(content, fileName, type);
@@ -115,7 +115,7 @@ function buildFileName(scripting: IScriptingDefinition) {
   return fileName;
 }
 
-async function executeCode(context: IApplicationContext) {
+async function executeCode(context: IReadOnlyApplicationContext) {
   const runner = new CodeRunner();
   await runner.runCode(
     /*code*/ context.state.code.current,

src/presentation/components/Code/TheCodeArea.vue

@@ -17,7 +17,7 @@ import 'ace-builds/webpack-resolver';
 import { ICodeChangedEvent } from '@/application/Context/State/Code/Event/ICodeChangedEvent';
 import { IScript } from '@/domain/IScript';
 import { ScriptingLanguage } from '@/domain/ScriptingLanguage';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { CodeBuilderFactory } from '@/application/Context/State/Code/Generation/CodeBuilderFactory';
 import Responsive from '@/presentation/components/Shared/Responsive.vue';
 import { NonCollapsing } from '@/presentation/components/Scripts/View/Cards/NonCollapsingDirective';
@@ -45,7 +45,7 @@ export default class TheCodeArea extends StatefulVue {
     }
   }
 
-  protected handleCollectionState(newState: ICategoryCollectionState): void {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
     this.destroyEditor();
     this.editor = initializeEditor(this.theme, this.editorId, newState.collection.scripting.language);
     const appCode = newState.code;

src/presentation/components/Scripts/Menu/Selector/SelectionTypeHandler.ts

@@ -2,7 +2,7 @@ import { IScript } from '@/domain/IScript';
 import { SelectedScript } from '@/application/Context/State/Selection/SelectedScript';
 import { RecommendationLevel } from '@/domain/RecommendationLevel';
 import { scrambledEqual } from '@/application/Common/Array';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { ICategoryCollectionState, IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 
 export enum SelectionType {
     Standard,
@@ -34,7 +34,7 @@ export class SelectionTypeHandler {
 }
 
 interface ISingleTypeHandler {
-    isSelected: (state: ICategoryCollectionState) => boolean;
+    isSelected: (state: IReadOnlyCategoryCollectionState) => boolean;
     select: (state: ICategoryCollectionState) => void;
 }
 
@@ -62,7 +62,7 @@ function getRecommendationLevelSelector(level: RecommendationLevel): ISingleType
     };
 }
 
-function hasAllSelectedLevelOf(level: RecommendationLevel, state: ICategoryCollectionState) {
+function hasAllSelectedLevelOf(level: RecommendationLevel, state: IReadOnlyCategoryCollectionState) {
     const scripts = state.collection.getScriptsByLevel(level);
     const selectedScripts = state.selection.selectedScripts;
     return areAllSelected(scripts, selectedScripts);

src/presentation/components/Scripts/Menu/TheOsChanger.vue

@@ -13,7 +13,7 @@
 import { Component } from 'vue-property-decorator';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { ApplicationFactory } from '@/application/ApplicationFactory';
 import MenuOptionList from './MenuOptionList.vue';
 import MenuOptionListItem from './MenuOptionListItem.vue';
@@ -38,7 +38,7 @@ export default class TheOsChanger extends StatefulVue {
     context.changeContext(newOs);
   }
 
-  protected handleCollectionState(newState: ICategoryCollectionState): void {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
     this.currentOs = newState.os;
     this.$forceUpdate(); // v-bind:class is not updated otherwise
   }

src/presentation/components/Scripts/Menu/TheScriptsMenu.vue

@@ -15,7 +15,7 @@ import TheOsChanger from './TheOsChanger.vue';
 import TheSelector from './Selector/TheSelector.vue';
 import TheViewChanger from './View/TheViewChanger.vue';
 import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { IEventSubscription } from '@/infrastructure/Events/IEventSource';
 
 @Component({
@@ -37,11 +37,11 @@ export default class TheScriptsMenu extends StatefulVue {
   protected initialize(): void {
     return;
   }
-  protected handleCollectionState(newState: ICategoryCollectionState): void {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
     this.subscribe(newState);
   }
 
-  private subscribe(state: ICategoryCollectionState) {
+  private subscribe(state: IReadOnlyCategoryCollectionState) {
       this.listeners.push(state.filter.filterRemoved.on(() => {
           this.isSearching = false;
       }));

src/presentation/components/Scripts/View/Cards/CardList.vue

@@ -31,7 +31,7 @@ import { Component } from 'vue-property-decorator';
 import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
 import { ICategory } from '@/domain/ICategory';
 import { hasDirective } from './NonCollapsingDirective';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 
 @Component({
   components: {
@@ -56,7 +56,7 @@ export default class CardList extends StatefulVue {
     this.activeCategoryId = isExpanded ? categoryId : undefined;
   }
 
-  protected handleCollectionState(newState: ICategoryCollectionState, oldState: ICategoryCollectionState): void {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
     this.setCategories(newState.collection.actions);
     this.activeCategoryId = undefined;
   }

src/presentation/components/Scripts/View/ScriptsTree/SelectableTree/Node/RevertToggle.vue

@@ -19,7 +19,7 @@ import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
 import { INode } from './INode';
 import { SelectedScript } from '@/application/Context/State/Selection/SelectedScript';
 import { getReverter } from './Reverter/ReverterFactory';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 
 @Component
 export default class RevertToggle extends StatefulVue {
@@ -37,7 +37,7 @@ export default class RevertToggle extends StatefulVue {
         this.handler.selectWithRevertState(this.isReverted, context.state.selection);
     }
 
-    protected handleCollectionState(newState: ICategoryCollectionState): void {
+    protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
         this.updateStatus(newState.selection.selectedScripts);
         this.events.unsubscribeAll();
         this.events.register(newState.selection.changed.on((scripts) => this.updateStatus(scripts)));

src/presentation/components/Scripts/View/TheScriptsView.vue

@@ -36,7 +36,7 @@ import { Component, Prop } from 'vue-property-decorator';
 import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
 import { ViewType } from '@/presentation/components/Scripts/Menu/View/ViewType';
 import { IFilterResult } from '@/application/Context/State/Filter/IFilterResult';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { ApplicationFactory } from '@/application/ApplicationFactory';
 
 /** Shows content of single category or many categories */
@@ -74,12 +74,12 @@ export default class TheScriptsView extends StatefulVue {
         filter.removeFilter();
     }
 
-    protected handleCollectionState(newState: ICategoryCollectionState): void {
+    protected handleCollectionState(newState: IReadOnlyCategoryCollectionState): void {
         this.events.unsubscribeAll();
         this.subscribeState(newState);
     }
 
-    private subscribeState(state: ICategoryCollectionState) {
+    private subscribeState(state: IReadOnlyCategoryCollectionState) {
         this.events.register(
             state.filter.filterRemoved.on(() => {
                 this.isSearching = false;

src/presentation/components/Shared/StatefulVue.ts

@@ -3,7 +3,7 @@ import { AsyncLazy } from '@/infrastructure/Threading/AsyncLazy';
 import { IApplicationContext } from '@/application/Context/IApplicationContext';
 import { buildContext } from '@/application/Context/ApplicationContextFactory';
 import { IApplicationContextChangedEvent } from '@/application/Context/IApplicationContext';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 import { EventSubscriptionCollection } from '@/infrastructure/Events/EventSubscriptionCollection';
 
 // @ts-ignore because https://github.com/vuejs/vue-class-component/issues/91
@@ -26,7 +26,8 @@ export abstract class StatefulVue extends Vue {
     }
 
     protected abstract handleCollectionState(
-        newState: ICategoryCollectionState, oldState: ICategoryCollectionState | undefined): void;
+        newState: IReadOnlyCategoryCollectionState,
+        oldState: IReadOnlyCategoryCollectionState | undefined): void;
     protected getCurrentContext(): Promise<IApplicationContext> {
         return StatefulVue.instance.getValue();
     }

src/presentation/components/TheSearchBar.vue

@@ -13,9 +13,9 @@
 import { Component, Watch } from 'vue-property-decorator';
 import { StatefulVue } from '@/presentation/components/Shared/StatefulVue';
 import { NonCollapsing } from '@/presentation/components/Scripts/View/Cards/NonCollapsingDirective';
-import { IUserFilter } from '@/application/Context/State/Filter/IUserFilter';
+import { IReadOnlyUserFilter } from '@/application/Context/State/Filter/IUserFilter';
 import { IFilterResult } from '@/application/Context/State/Filter/IFilterResult';
-import { ICategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
+import { IReadOnlyCategoryCollectionState } from '@/application/Context/State/ICategoryCollectionState';
 
 @Component( {
     directives: { NonCollapsing },
@@ -36,7 +36,7 @@ export default class TheSearchBar extends StatefulVue {
     }
   }
 
-  protected handleCollectionState(newState: ICategoryCollectionState, oldState: ICategoryCollectionState | undefined) {
+  protected handleCollectionState(newState: IReadOnlyCategoryCollectionState) {
     const totalScripts = newState.collection.totalScripts;
     this.searchPlaceHolder = `Search in ${totalScripts} scripts`;
     this.searchQuery = newState.filter.currentFilter ? newState.filter.currentFilter.query : '';
@@ -44,7 +44,7 @@ export default class TheSearchBar extends StatefulVue {
     this.subscribeFilter(newState.filter);
   }
 
-  private subscribeFilter(filter: IUserFilter) {
+  private subscribeFilter(filter: IReadOnlyUserFilter) {
     this.events.register(filter.filtered.on((result) => this.handleFiltered(result)));
     this.events.register(filter.filterRemoved.on(() => this.handleFilterRemoved()));
   }