Enhancement: disable add split button when approrpriate (#7215)

src-ui/src/app/components/common/confirm-dialog/split-confirm-dialog/split-confirm-dialog.component.html

@@ -23,7 +23,7 @@
         </div>
         <div class="col-4">
             <div class="d-grid">
-                <button class="btn btn-sm btn-primary" (click)="addSplit()" [disabled]="page === totalPages">
+                <button class="btn btn-sm btn-primary" (click)="addSplit()" [disabled]="!canSplit">
                     <i-bs name="plus-circle"></i-bs>&nbsp;
                     <span i18n>Add Split</span>
                 </button>

src-ui/src/app/components/common/confirm-dialog/split-confirm-dialog/split-confirm-dialog.component.spec.ts

@@ -92,4 +92,16 @@ describe('SplitConfirmDialogComponent', () => {
     component.pdfPreviewLoaded({ numPages: 5 } as any)
     expect(component.totalPages).toEqual(5)
   })
+
+  it('should correctly disable split button', () => {
+    component.totalPages = 5
+    component.page = 1
+    expect(component.canSplit).toBeTruthy()
+    component.page = 5
+    expect(component.canSplit).toBeFalsy()
+    component.page = 4
+    expect(component.canSplit).toBeTruthy()
+    component['pages'] = new Set([1, 2, 3, 4])
+    expect(component.canSplit).toBeFalsy()
+  })
 })

src-ui/src/app/components/common/confirm-dialog/split-confirm-dialog/split-confirm-dialog.component.ts

@@ -42,6 +42,14 @@ export class SplitConfirmDialogComponent
   public totalPages: number
   public deleteOriginal: boolean = false
 
+  public get canSplit(): boolean {
+    return (
+      this.page < this.totalPages &&
+      this.pages.size < this.totalPages - 1 &&
+      !this.pages.has(this.page)
+    )
+  }
+
   public get pdfSrc(): string {
     return this.documentService.getPreviewUrl(this.documentID)
   }