Add order buttons in frontend

frontend/src/app/data-entry/source/episode-preview/episode-preview.component.html

@@ -12,11 +12,17 @@
                     <span *ngIf="episode.page" class="inline-list-item">page {{ episode.page }}</span>
                 </small>
             </div>
-            <lc-action-button-group
-                [editLink]="['/', 'data-entry', 'episodes', episode.id]"
-                (deleteAction)="onClickDelete(episode.id)"
-                [showButtonText]="false"
-            />
+            <div class="button-group-wrapper">
+                <lc-order-button-group
+                    entityName="episode"
+                    (changeOrder)="changeEpisodeOrder.emit($event)"
+                />
+                <lc-action-button-group
+                    [editLink]="['/', 'data-entry', 'episodes', episode.id]"
+                    (deleteAction)="onClickDelete(episode.id)"
+                    [showButtonText]="false"
+                />
+            </div>
         </div>
     </div>
     <div class="card-body">

frontend/src/app/data-entry/source/episode-preview/episode-preview.component.scss

@@ -0,0 +1,5 @@
+.button-group-wrapper {
+    display: flex;
+    align-items: center;
+    gap: 1rem;
+}

frontend/src/app/data-entry/source/episode-preview/episode-preview.component.ts

@@ -1,9 +1,16 @@
-import { Component, DestroyRef, Input } from "@angular/core";
+import {
+    Component,
+    DestroyRef,
+    EventEmitter,
+    Input,
+    Output,
+} from "@angular/core";
 import { takeUntilDestroyed } from "@angular/core/rxjs-interop";
 import { ModalService } from "@services/modal.service";
 import { ToastService } from "@services/toast.service";
 import { dataIcons } from "@shared/icons";
 import { agentIcon, locationIcon } from "@shared/icons-utils";
+import { OrderChange } from "@shared/order-button-group/order-button-group.component";
 import {
     DataEntryDeleteEpisodeGQL,
     DataEntrySourceDetailQuery,
@@ -21,7 +28,12 @@ type QueriedEpisode = NonNullable<
 export class EpisodePreviewComponent {
     @Input({ required: true })
     public episode!: QueriedEpisode;
+
+    @Output()
+    public changeEpisodeOrder = new EventEmitter<OrderChange>();
+
     public dataIcons = dataIcons;
+
     agentIcon = agentIcon;
     locationIcon = locationIcon;
 
@@ -40,7 +52,8 @@ export class EpisodePreviewComponent {
             })
             .then(() => {
                 this.performDelete(episodeId);
-            }).catch(() => {
+            })
+            .catch(() => {
                 // Do nothing on cancel / dismissal.
             });
     }

frontend/src/app/data-entry/source/source.component.html

@@ -19,6 +19,7 @@ <h2 class="mb-4">Episodes</h2>
     <lc-episode-preview
         *ngFor="let episode of source.episodes; trackBy: identify"
         [episode]="episode"
+        (changeEpisodeOrder)="reorderEpisodes(source.episodes, episode.id, $event)"
     />
 </div>
 <div class="btn-group mb-4" *ngIf="source$ | async as source">

frontend/src/app/data-entry/source/source.component.ts

@@ -1,10 +1,22 @@
-import { Component, computed, TemplateRef } from "@angular/core";
-import { toSignal } from "@angular/core/rxjs-interop";
+import { Component, computed, DestroyRef, TemplateRef } from "@angular/core";
+import { takeUntilDestroyed, toSignal } from "@angular/core/rxjs-interop";
 import { ActivatedRoute, Router } from "@angular/router";
 import { NgbModal, NgbModalRef } from "@ng-bootstrap/ng-bootstrap";
+import { ToastService } from "@services/toast.service";
 import { actionIcons, dataIcons } from "@shared/icons";
-import { DataEntrySourceDetailGQL, EpisodeType } from "generated/graphql";
+import {
+    DataEntrySourceDetailGQL,
+    DataEntrySourceDetailQuery,
+    DataEntryUpdateEpisodeOrderGQL,
+    DataEntryUpdateEpisodeOrderMutation,
+    EpisodeType,
+} from "generated/graphql";
 import { map, shareReplay, switchMap } from "rxjs";
+import { MutationResult } from "apollo-angular";
+import { moveItemInArray } from "@shared/utils";
+import { OrderChange } from "@shared/order-button-group/order-button-group.component";
+
+type QueriedEpisode = DataEntrySourceDetailQuery["source"]["episodes"][number];
 
 @Component({
     selector: "lc-source",
@@ -35,9 +47,7 @@ export class SourceComponent {
     );
 
     public sourceTitle = toSignal(
-        this.source$.pipe(
-            map((source) => source.name)
-        ),
+        this.source$.pipe(map((source) => source.name)),
         { initialValue: "" }
     );
 
@@ -48,10 +58,13 @@ export class SourceComponent {
     public mutationInProgress = false;
 
     constructor(
+        private destroyRef: DestroyRef,
         private route: ActivatedRoute,
         private router: Router,
         private modalService: NgbModal,
-        private sourceDetailQuery: DataEntrySourceDetailGQL
+        private toastService: ToastService,
+        private sourceDetailQuery: DataEntrySourceDetailGQL,
+        private updateEpisodeOrder: DataEntryUpdateEpisodeOrderGQL
     ) {}
 
     public openNewEpisodeModal(newEpisodeModal: TemplateRef<unknown>): void {
@@ -75,4 +88,65 @@ export class SourceComponent {
     public identify(_index: number, item: Pick<EpisodeType, "id">): string {
         return item.id;
     }
+
+    public reorderEpisodes(
+        episodes: QueriedEpisode[],
+        episodeId: string,
+        change: OrderChange
+    ): void {
+        const episodeIds = episodes.map((episode) => episode.id);
+        const currentIndex = episodeIds.indexOf(episodeId);
+
+        const indexNotFound = currentIndex === -1;
+        const indexAtBoundary =
+            (change === "up" && currentIndex <= 0) ||
+            (change === "down" && currentIndex >= episodeIds.length - 1);
+
+        // Don't mutate if the order change is invalid.
+        if (indexNotFound || indexAtBoundary) {
+            return;
+        }
+
+        const newIndex = change === "up" ? currentIndex - 1 : currentIndex + 1;
+        const newOrder = moveItemInArray(episodeIds, currentIndex, newIndex);
+
+        this.updateEpisodeOrder
+            .mutate(
+                {
+                    episodeIds: newOrder,
+                },
+                {
+                    update: (cache) => cache.evict({ fieldName: "source" }),
+                }
+            )
+            .pipe(takeUntilDestroyed(this.destroyRef))
+            .subscribe((result) => {
+                this.onOrderMutationResult(result);
+            });
+    }
+
+    private onOrderMutationResult(
+        result: MutationResult<DataEntryUpdateEpisodeOrderMutation>
+    ): void {
+        const graphQLErrors = result.errors;
+        const mutationErrors = result.data?.updateEpisodeOrder?.errors;
+
+        if (graphQLErrors?.length) {
+            const messages = graphQLErrors.map((error) => error.message);
+            this.toastService.show({
+                type: "danger",
+                header: "Failed to save episode order",
+                body: messages.join("\n\n"),
+            });
+        } else if (mutationErrors?.length) {
+            const messages = mutationErrors.map(
+                (error) => `${error.field}: ${error.messages.join("\n")}`
+            );
+            this.toastService.show({
+                type: "danger",
+                header: "Failed to save episode order",
+                body: messages.join("\n\n"),
+            });
+        }
+    }
 }

frontend/src/app/data-entry/source/source.graphql

@@ -36,3 +36,13 @@ query DataEntrySourceDetail($id: ID!) {
         }
     }
 }
+
+mutation DataEntryUpdateEpisodeOrder($episodeIds: [ID!]!) {
+    updateEpisodeOrder(episodeIds: $episodeIds) {
+        ok
+        errors {
+            field
+            messages
+        }
+    }
+}

frontend/src/app/shared/icons.ts

@@ -18,6 +18,8 @@ export const actionIcons = {
     expand: 'caret-down',
     collapse: 'caret-up',
     edit: 'pencil',
+    up: 'chevron-up',
+    down: 'chevron-down',
 };
 
 export const authIcons = {

frontend/src/app/shared/order-button-group/order-button-group.component.html

@@ -0,0 +1,14 @@
+<div class="btn-group">
+    <button type="button" class="btn btn-light" (click)="onUp()">
+        <lc-icon
+            [icon]="actionIcons.up"
+            [title]="entityName ? 'Move ' + entityName + ' up' : 'Move up'"
+        />
+    </button>
+    <button type="button" class="btn btn-light" (click)="onDown()">
+        <lc-icon
+            [icon]="actionIcons.down"
+            [title]="entityName ? 'Move ' + entityName + ' down' : 'Move down'"
+        />
+    </button>
+</div>

frontend/src/app/shared/order-button-group/order-button-group.component.spec.ts

@@ -0,0 +1,23 @@
+import { ComponentFixture, TestBed } from "@angular/core/testing";
+
+import { OrderButtonGroupComponent } from "./order-button-group.component";
+import { SharedTestingModule } from "@shared/shared-testing.module";
+
+describe("OrderButtonGroupComponent", () => {
+    let component: OrderButtonGroupComponent;
+    let fixture: ComponentFixture<OrderButtonGroupComponent>;
+
+    beforeEach(() => {
+        TestBed.configureTestingModule({
+            declarations: [OrderButtonGroupComponent],
+            imports: [SharedTestingModule],
+        });
+        fixture = TestBed.createComponent(OrderButtonGroupComponent);
+        component = fixture.componentInstance;
+        fixture.detectChanges();
+    });
+
+    it("should create", () => {
+        expect(component).toBeTruthy();
+    });
+});

frontend/src/app/shared/order-button-group/order-button-group.component.ts

@@ -0,0 +1,24 @@
+import { Component, EventEmitter, Input, Output } from "@angular/core";
+import { actionIcons } from "@shared/icons";
+
+export type OrderChange = "up" | "down";
+
+@Component({
+    selector: "lc-order-button-group",
+    templateUrl: "./order-button-group.component.html",
+    styleUrls: ["./order-button-group.component.scss"],
+})
+export class OrderButtonGroupComponent {
+    @Input() entityName: string | null = null;
+    @Output() changeOrder = new EventEmitter<OrderChange>();
+
+    public actionIcons = actionIcons;
+
+    public onUp(): void {
+        this.changeOrder.emit("up");
+    }
+
+    public onDown(): void {
+        this.changeOrder.emit("down");
+    }
+}

frontend/src/app/shared/shared.module.ts

@@ -13,6 +13,7 @@ import { BaseModalComponent } from "./base-modal/base-modal.component";
 import { ConfirmationModalComponent } from './confirmation-modal/confirmation-modal.component';
 import { ContributorsComponent } from './contributors/contributors.component';
 import { CollapsibleCardComponent } from './collapsible-card/collapsible-card.component';
+import { OrderButtonGroupComponent } from './order-button-group/order-button-group.component';
 
 
 
@@ -25,6 +26,7 @@ import { CollapsibleCardComponent } from './collapsible-card/collapsible-card.co
         ConfirmationModalComponent,
         ContributorsComponent,
         CollapsibleCardComponent,
+        OrderButtonGroupComponent,
     ],
     imports: [
         CommonModule,
@@ -47,6 +49,7 @@ import { CollapsibleCardComponent } from './collapsible-card/collapsible-card.co
         ActionButtonGroupComponent,
         ContributorsComponent,
         CollapsibleCardComponent,
+        OrderButtonGroupComponent,
         CommonModule,
         BrowserModule,
         BrowserAnimationsModule,

frontend/src/app/shared/utils.spec.ts

@@ -1,4 +1,4 @@
-import { differenceBy, splat } from "./utils";
+import { differenceBy, moveItemInArray, splat } from "./utils";
 
 describe('differenceBy', () => {
     it('should compare lists', () => {
@@ -21,3 +21,26 @@ describe('splat', () => {
         expect(splat(Math.min)([3, 5, 2])).toBe(2)
     });
 });
+
+describe("moveItemInArray", () => {
+    it("should move an item in an array", () => {
+        const array = ["Alice", "Bernard", "Claire", "David", "Eve"];
+        expect(moveItemInArray(array, 1, 3)).toEqual([
+            "Alice",
+            "Claire",
+            "David",
+            "Bernard",
+            "Eve",
+        ]);
+    });
+
+    it("should return the same array if the indices are the same", () => {
+        const array = ["Alice", "Bernard", "Claire", "David", "Eve"];
+        expect(moveItemInArray(array, 4, 4)).toBe(array);
+    });
+
+    it("should return the same array if the indices are out of bounds", () => {
+        const array = ["Alice", "Bernard", "Claire", "David", "Eve"];
+        expect(moveItemInArray(array, -99, 99)).toBe(array);
+    });
+});

frontend/src/app/shared/utils.ts

@@ -35,3 +35,29 @@ export const differenceBy = <T extends object>(
  */
 export const splat = <I, O>(func: (...a: I[]) => O) =>
     (args: I[]) => func(...args);
+
+
+/**
+ * Moves an item within an array from one index to another. Returns the same array if the from and to indices are identical or out of bounds.
+ *
+ * @param {T[]} array - The array containing the item to move.
+ * @param {number} fromIndex - The index of the item to move.
+ * @param {number} toIndex - The index to move the item to.
+ * @returns {T[]} The array with the item moved to the new index.
+ */
+export function moveItemInArray<T>(array: T[], fromIndex: number, toIndex: number): T[] {
+    if (fromIndex === toIndex) {
+        return array;
+    }
+
+    const fromIndexOutOfBounds = fromIndex < 0 || fromIndex >= array.length;
+    const toIndexOutOfBounds = toIndex < 0 || toIndex >= array.length;
+
+    if (fromIndexOutOfBounds || toIndexOutOfBounds) {
+        return array;
+    }
+
+    const item = array.splice(fromIndex, 1)[0];
+    array.splice(toIndex, 0, item);
+    return array;
+}