2 * <eg-combobox [allowFreeText]="true" [entries]="comboboxEntryList"/>
3 * <!-- see also <eg-combobox-entry> -->
6 import {Component, OnInit, Input, Output, ViewChild,
7 Directive, ViewChildren, QueryList, AfterViewInit,
8 OnChanges, SimpleChanges,
9 TemplateRef, EventEmitter, ElementRef, forwardRef} from '@angular/core';
10 import {ControlValueAccessor, NG_VALUE_ACCESSOR} from '@angular/forms';
11 import {Observable, of, Subject} from 'rxjs';
12 import {map, tap, reduce, mergeMap, mapTo, debounceTime, distinctUntilChanged, merge, filter} from 'rxjs/operators';
13 import {NgbTypeahead, NgbTypeaheadSelectItemEvent} from '@ng-bootstrap/ng-bootstrap';
14 import {StoreService} from '@eg/core/store.service';
15 import {IdlService, IdlObject} from '@eg/core/idl.service';
16 import {PcrudService} from '@eg/core/pcrud.service';
17 import {OrgService} from '@eg/core/org.service';
19 export interface ComboboxEntry {
21 // If no label is provided, the 'id' value is used.
24 userdata?: any; // opaque external value; ignored by this component.
29 selector: 'ng-template[egIdlClass]'
31 export class IdlClassTemplateDirective {
32 @Input() egIdlClass: string;
33 constructor(public template: TemplateRef<any>) {}
37 selector: 'eg-combobox',
38 templateUrl: './combobox.component.html',
40 .icons {margin-left:-18px}
41 .material-icons {font-size: 16px;font-weight:bold}
44 provide: NG_VALUE_ACCESSOR,
45 useExisting: forwardRef(() => ComboboxComponent),
49 export class ComboboxComponent implements ControlValueAccessor, OnInit, AfterViewInit, OnChanges {
51 selected: ComboboxEntry;
52 click$: Subject<string>;
53 entrylist: ComboboxEntry[];
55 @ViewChild('instance', { static: true }) instance: NgbTypeahead;
56 @ViewChild('defaultDisplayTemplate', { static: true}) defaultDisplayTemplate: TemplateRef<any>;
57 @ViewChildren(IdlClassTemplateDirective) idlClassTemplates: QueryList<IdlClassTemplateDirective>;
59 // Applies a name attribute to the input.
61 @Input() name: string;
63 // Placeholder text for selector input
64 @Input() placeholder = '';
66 @Input() persistKey: string; // TODO
68 @Input() allowFreeText = false;
70 @Input() inputSize: number = null;
72 // Add a 'required' attribute to the input
74 @Input() set required(r: boolean) {
80 @Input() set disabled(d: boolean) {
84 // Entry ID of the default entry to select (optional)
85 // onChange() is NOT fired when applying the default value,
86 // unless startIdFiresOnChange is set to true.
87 @Input() startId: any = null;
88 @Input() idlClass: string;
89 @Input() startIdFiresOnChange: boolean;
91 // Allow the selected entry ID to be passed via the template
92 // This does NOT not emit onChange events.
93 @Input() set selectedId(id: any) {
94 if (id === undefined) { return; }
96 // clear on explicit null
97 if (id === null) { this.selected = null; }
99 if (this.entrylist.length) {
100 this.selected = this.entrylist.filter(e => e.id === id)[0];
103 if (!this.selected) {
104 // It's possible the selected ID lives in a set of entries
105 // that are yet to be provided.
108 this.pcrud.retrieve(this.idlClass, id)
112 label: this.getFmRecordLabel(rec),
115 this.selected = this.entrylist.filter(e => e.id === id)[0];
121 get selectedId(): any {
122 return this.selected ? this.selected.id : null;
125 @Input() idlField: string;
126 @Input() idlIncludeLibraryInLabel: string;
127 @Input() asyncDataSource: (term: string) => Observable<ComboboxEntry>;
129 // If true, an async data search is allowed to fetch all
130 // values when given an empty term. This should be used only
131 // if the maximum number of entries returned by the data source
132 // is known to be no more than a couple hundred.
133 @Input() asyncSupportsEmptyTermClick: boolean;
135 // Useful for efficiently preventing duplicate async entries
136 asyncIds: {[idx: string]: boolean};
138 // True if a default selection has been made.
139 defaultSelectionApplied: boolean;
141 @Input() set entries(el: ComboboxEntry[]) {
144 if (this.entrylistMatches(el)) {
145 // Avoid reprocessing data we already have.
151 // new set of entries essentially means a new instance. reset.
152 this.defaultSelectionApplied = false;
153 this.applySelection();
155 // It's possible to provide an entrylist at load time, but
156 // fetch all future data via async data source. Track the
157 // values we already have so async lookup won't add them again.
158 // A new entry list wipes out any existing async values.
160 el.forEach(entry => this.asyncIds['' + entry.id] = true);
164 // When provided use this as the display template for each entry.
165 @Input() displayTemplate: TemplateRef<any>;
167 // Emitted when the value is changed via UI.
168 // When the UI value is cleared, null is emitted.
169 @Output() onChange: EventEmitter<ComboboxEntry>;
171 // Useful for massaging the match string prior to comparison
172 // and display. Default version trims leading/trailing spaces.
173 formatDisplayString: (e: ComboboxEntry) => string;
175 idlDisplayTemplateMap: { [key: string]: TemplateRef<any> } = {};
176 getFmRecordLabel: (fm: IdlObject) => string;
178 // Stub functions required by ControlValueAccessor
179 propagateChange = (_: any) => {};
180 propagateTouch = () => {};
183 private elm: ElementRef,
184 private store: StoreService,
185 private idl: IdlService,
186 private pcrud: PcrudService,
187 private org: OrgService,
191 this.click$ = new Subject<string>();
192 this.onChange = new EventEmitter<ComboboxEntry>();
193 this.defaultSelectionApplied = false;
195 this.formatDisplayString = (result: ComboboxEntry) => {
196 const display = result.label || result.id;
197 return (display + '').trim();
200 this.getFmRecordLabel = (fm: IdlObject) => {
201 // FIXME: it would be cleaner if we could somehow use
202 // the per-IDL-class ng-templates directly
203 switch (this.idlClass) {
205 return fm.course_number() + ': ' + fm.name();
208 return fm.code() + ' (' + fm.year() + ')';
211 return fm.name() + ' (' + this.getOrgShortname(fm.owning_lib()) + ')';
214 const field = this.idlField;
215 if (this.idlIncludeLibraryInLabel) {
216 return fm[field]() + ' (' + fm[this.idlIncludeLibraryInLabel]().shortname() + ')';
226 const classDef = this.idl.classes[this.idlClass];
227 const pkeyField = classDef.pkey;
230 throw new Error(`IDL class ${this.idlClass} has no pkey field`);
233 if (!this.idlField) {
234 this.idlField = this.idl.getClassSelector(this.idlClass);
237 this.asyncDataSource = term => {
238 const field = this.idlField;
240 const extra_args = { order_by : {} };
241 args[field] = {'ilike': `%${term}%`}; // could -or search on label
242 extra_args['order_by'][this.idlClass] = field;
243 extra_args['limit'] = 100;
244 if (this.idlIncludeLibraryInLabel) {
245 extra_args['flesh'] = 1;
246 const flesh_fields: Object = {};
247 flesh_fields[this.idlClass] = [ this.idlIncludeLibraryInLabel ];
248 extra_args['flesh_fields'] = flesh_fields;
249 return this.pcrud.search(this.idlClass, args, extra_args).pipe(map(data => {
251 id: data[pkeyField](),
252 label: this.getFmRecordLabel(data),
257 return this.pcrud.search(this.idlClass, args, extra_args).pipe(map(data => {
258 return {id: data[pkeyField](), label: this.getFmRecordLabel(data), fm: data};
266 this.idlDisplayTemplateMap = this.idlClassTemplates.reduce((acc, cur) => {
267 acc[cur.egIdlClass] = cur.template;
272 ngOnChanges(changes: SimpleChanges) {
273 let firstTime = true;
274 Object.keys(changes).forEach(key => {
275 if (!changes[key].firstChange) {
280 if ('selectedId' in changes) {
281 if (!changes.selectedId.currentValue) {
282 this.selected = null;
285 if ('idlClass' in changes) {
286 if (!('idlField' in changes)) {
287 // let ngOnInit reset it to the
288 // selector of the new IDL class
289 this.idlField = null;
292 this.entrylist.length = 0;
293 this.selected = null;
300 this.click$.next($event.target.value);
303 getResultTemplate(): TemplateRef<any> {
304 if (this.displayTemplate) {
305 return this.displayTemplate;
307 if (this.idlClass in this.idlDisplayTemplateMap) {
308 return this.idlDisplayTemplateMap[this.idlClass];
310 return this.defaultDisplayTemplate;
313 getOrgShortname(ou: any) {
314 if (typeof ou === 'object') {
315 return ou.shortname();
317 return this.org.get(ou).shortname();
322 // Give the input a chance to focus then fire the click
323 // handler to force open the typeahead
324 this.elm.nativeElement.getElementsByTagName('input')[0].focus();
325 setTimeout(() => this.click$.next(''));
328 // Returns true if the 2 entries are equivalent.
329 entriesMatch(e1: ComboboxEntry, e2: ComboboxEntry): boolean {
333 e1.label === e2.label &&
334 e1.freetext === e2.freetext
338 // Returns true if the 2 lists are equivalent.
339 entrylistMatches(el: ComboboxEntry[]): boolean {
340 if (el.length === 0 && this.entrylist.length === 0) {
341 // Empty arrays are only equivalent if they are the same array,
342 // since the caller may provide an array that starts empty, but
343 // is later populated.
344 return el === this.entrylist;
346 if (el.length !== this.entrylist.length) {
349 for (let i = 0; i < el.length; i++) {
350 const mine = this.entrylist[i];
351 if (!mine || !this.entriesMatch(mine, el[i])) {
358 // Apply a default selection where needed
361 if (this.startId !== null &&
362 this.entrylist && !this.defaultSelectionApplied) {
365 this.entrylist.filter(e => e.id === this.startId)[0];
368 this.selected = entry;
369 this.defaultSelectionApplied = true;
370 if (this.startIdFiresOnChange) {
371 this.selectorChanged(
372 {item: this.selected, preventDefault: () => true});
378 // Called by combobox-entry.component
379 addEntry(entry: ComboboxEntry) {
380 this.entrylist.push(entry);
381 this.applySelection();
384 // Manually set the selected value by ID.
385 // This does NOT fire the onChange handler.
386 // DEPRECATED: use this.selectedId = abc or [selectedId]="abc" instead.
387 applyEntryId(entryId: any) {
388 this.selected = this.entrylist.filter(e => e.id === entryId)[0];
391 addAsyncEntry(entry: ComboboxEntry) {
392 // Avoid duplicate async entries
393 if (!this.asyncIds['' + entry.id]) {
394 this.asyncIds['' + entry.id] = true;
395 this.addEntry(entry);
399 hasEntry(entryId: any): boolean {
400 return this.entrylist.filter(e => e.id === entryId)[0] !== undefined;
404 // When the selected value is a string it means we have either
405 // no value (user cleared the input) or a free-text value.
407 if (typeof this.selected === 'string') {
409 if (this.allowFreeText && this.selected !== '') {
410 // Free text entered which does not match a known entry
411 // translate it into a dummy ComboboxEntry
414 label: this.selected,
420 this.selected = null;
423 // Manually fire the onchange since NgbTypeahead fails
424 // to fire the onchange when the value is cleared.
425 this.selectorChanged(
426 {item: this.selected, preventDefault: () => true});
428 this.propagateTouch();
431 // Fired by the typeahead to inform us of a change.
432 selectorChanged(selEvent: NgbTypeaheadSelectItemEvent) {
433 this.onChange.emit(selEvent.item);
434 this.propagateChange(selEvent.item);
437 // Adds matching async entries to the entry list
438 // and propagates the search term for pipelining.
439 addAsyncEntries(term: string): Observable<string> {
441 if (!term || !this.asyncDataSource) {
445 let searchTerm: string;
447 if (searchTerm === '_CLICK_') {
448 if (this.asyncSupportsEmptyTermClick) {
455 return new Observable(observer => {
456 this.asyncDataSource(searchTerm).subscribe(
457 (entry: ComboboxEntry) => this.addAsyncEntry(entry),
460 observer.next(searchTerm);
467 filter = (text$: Observable<string>): Observable<ComboboxEntry[]> => {
470 distinctUntilChanged(),
472 // Merge click actions in with the stream of text entry
474 // Inject a specifier indicating the source of the
475 // action is a user click instead of a text entry.
476 // This tells the filter to show all values in sync mode.
477 this.click$.pipe(filter(() =>
478 !this.instance.isPopupOpen()
479 )).pipe(mapTo('_CLICK_'))
482 // mergeMap coalesces an observable into our stream.
483 mergeMap(term => this.addAsyncEntries(term)),
484 map((term: string) => {
486 // Display no values when the input is empty and no
487 // click action occurred.
488 if (term === '') { return []; }
490 // In sync-data mode, a click displays the full list.
491 if (term === '_CLICK_' && !this.asyncDataSource) {
492 return this.entrylist;
495 // Filter entrylist whose labels substring-match the
497 return this.entrylist.filter(entry => {
498 const label = entry.label || entry.id;
499 return label.toLowerCase().indexOf(term.toLowerCase()) > -1;
505 writeValue(value: ComboboxEntry) {
506 if (value !== undefined && value !== null) {
507 this.startId = value.id;
508 this.applySelection();
512 registerOnChange(fn) {
513 this.propagateChange = fn;
516 registerOnTouched(fn) {
517 this.propagateTouch = fn;