Feature: Implement custom fields for documents (#4502)

Adds custom fields of certain data types, attachable to documents and searchable

Co-Authored-By: Trenton H <797416+stumpylog@users.noreply.github.com>

src-ui/src/app/components/common/custom-fields-dropdown/custom-fields-dropdown.component.ts

@@ -0,0 +1,131 @@
+import {
+  Component,
+  EventEmitter,
+  Input,
+  OnDestroy,
+  Output,
+} from '@angular/core'
+import { NgbModal } from '@ng-bootstrap/ng-bootstrap'
+import { Subject, first, takeUntil } from 'rxjs'
+import { PaperlessCustomField } from 'src/app/data/paperless-custom-field'
+import { PaperlessCustomFieldInstance } from 'src/app/data/paperless-custom-field-instance'
+import { CustomFieldsService } from 'src/app/services/rest/custom-fields.service'
+import { ToastService } from 'src/app/services/toast.service'
+import { CustomFieldEditDialogComponent } from '../edit-dialog/custom-field-edit-dialog/custom-field-edit-dialog.component'
+import {
+  PermissionAction,
+  PermissionType,
+  PermissionsService,
+} from 'src/app/services/permissions.service'
+
+@Component({
+  selector: 'pngx-custom-fields-dropdown',
+  templateUrl: './custom-fields-dropdown.component.html',
+  styleUrls: ['./custom-fields-dropdown.component.scss'],
+})
+export class CustomFieldsDropdownComponent implements OnDestroy {
+  @Input()
+  documentId: number
+
+  @Input()
+  disabled: boolean = false
+
+  @Input()
+  existingFields: PaperlessCustomFieldInstance[] = []
+
+  @Output()
+  added: EventEmitter<PaperlessCustomField> = new EventEmitter()
+
+  @Output()
+  created: EventEmitter<PaperlessCustomField> = new EventEmitter()
+
+  private customFields: PaperlessCustomField[] = []
+  public unusedFields: PaperlessCustomField[]
+
+  public name: string
+
+  public field: number
+
+  private unsubscribeNotifier: Subject<any> = new Subject()
+
+  get placeholderText(): string {
+    return $localize`Choose field`
+  }
+
+  get notFoundText(): string {
+    return $localize`No unused fields found`
+  }
+
+  get canCreateFields(): boolean {
+    return this.permissionsService.currentUserCan(
+      PermissionAction.Add,
+      PermissionType.CustomField
+    )
+  }
+
+  constructor(
+    private customFieldsService: CustomFieldsService,
+    private modalService: NgbModal,
+    private toastService: ToastService,
+    private permissionsService: PermissionsService
+  ) {
+    this.getFields()
+  }
+
+  ngOnDestroy(): void {
+    this.unsubscribeNotifier.next(this)
+    this.unsubscribeNotifier.complete()
+  }
+
+  private getFields() {
+    this.customFieldsService
+      .listAll()
+      .pipe(first(), takeUntil(this.unsubscribeNotifier))
+      .subscribe((result) => {
+        this.customFields = result.results
+        this.updateUnusedFields()
+      })
+  }
+
+  public getCustomFieldFromInstance(
+    instance: PaperlessCustomFieldInstance
+  ): PaperlessCustomField {
+    return this.customFields.find((f) => f.id === instance.field)
+  }
+
+  private updateUnusedFields() {
+    this.unusedFields = this.customFields.filter(
+      (f) =>
+        !this.existingFields?.find(
+          (e) => this.getCustomFieldFromInstance(e)?.id === f.id
+        )
+    )
+  }
+
+  onOpenClose() {
+    this.field = undefined
+    this.updateUnusedFields()
+  }
+
+  addField() {
+    this.added.emit(this.customFields.find((f) => f.id === this.field))
+  }
+
+  createField(newName: string = null) {
+    const modal = this.modalService.open(CustomFieldEditDialogComponent)
+    if (newName) modal.componentInstance.object = { name: newName }
+    modal.componentInstance.succeeded
+      .pipe(takeUntil(this.unsubscribeNotifier))
+      .subscribe((newField) => {
+        this.toastService.showInfo($localize`Saved field "${newField.name}".`)
+        this.customFieldsService.clearCache()
+        this.getFields()
+        this.created.emit(newField)
+      })
+    modal.componentInstance.failed
+      .pipe(takeUntil(this.unsubscribeNotifier))
+      .subscribe((e) => {
+        this.toastService.showError($localize`Error saving field.`, e)
+      })
+  }
+}