Merge pull request #352 from koloml/refactor-autocomplete

Autocomplete: Extracting & slightly refactoring parts of the code
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liamwhite 2024-09-02 09:36:56 -04:00 committed by GitHub
commit f73befb439
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3 changed files with 588 additions and 181 deletions

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@ -3,42 +3,25 @@
*/
import { LocalAutocompleter } from './utils/local-autocompleter';
import { handleError } from './utils/requests';
import { getTermContexts } from './match_query';
import store from './utils/store';
import { TermContext } from './query/lex.ts';
import { $, $$, makeEl, removeEl } from './utils/dom.ts';
import { mouseMoveThenOver } from './utils/events.ts';
import { TermContext } from './query/lex';
import { $$ } from './utils/dom';
import { fetchLocalAutocomplete, fetchSuggestions, SuggestionsPopup, TermSuggestion } from './utils/suggestions';
type TermSuggestion = {
label: string;
value: string;
};
const cachedSuggestions: Record<string, TermSuggestion[]> = {};
let inputField: HTMLInputElement | null = null,
originalTerm: string | undefined,
originalQuery: string | undefined,
selectedTerm: TermContext | null = null;
function removeParent() {
const parent = $<HTMLElement>('.autocomplete');
if (parent) removeEl(parent);
}
function removeSelected() {
const selected = $<HTMLElement>('.autocomplete__item--selected');
if (selected) selected.classList.remove('autocomplete__item--selected');
}
const popup = new SuggestionsPopup();
function isSearchField(targetInput: HTMLElement): boolean {
return targetInput && targetInput.dataset.acMode === 'search';
}
function restoreOriginalValue() {
if (!inputField) {
return;
}
if (!inputField) return;
if (isSearchField(inputField) && originalQuery) {
inputField.value = originalQuery;
@ -50,9 +33,7 @@ function restoreOriginalValue() {
}
function applySelectedValue(selection: string) {
if (!inputField) {
return;
}
if (!inputField) return;
if (!isSearchField(inputField)) {
inputField.value = selection;
@ -67,21 +48,6 @@ function applySelectedValue(selection: string) {
}
}
function changeSelected(firstOrLast: Element | null, current: Element | null, sibling: Element | null) {
if (current && sibling) {
// if the currently selected item has a sibling, move selection to it
current.classList.remove('autocomplete__item--selected');
sibling.classList.add('autocomplete__item--selected');
} else if (current) {
// if the next keypress will take the user outside the list, restore the unautocompleted term
restoreOriginalValue();
removeSelected();
} else if (firstOrLast) {
// if no item in the list is selected, select the first or last
firstOrLast.classList.add('autocomplete__item--selected');
}
}
function isSelectionOutsideCurrentTerm(): boolean {
if (!inputField || !selectedTerm) return true;
if (inputField.selectionStart === null || inputField.selectionEnd === null) return true;
@ -93,127 +59,43 @@ function isSelectionOutsideCurrentTerm(): boolean {
}
function keydownHandler(event: KeyboardEvent) {
const selected = $<HTMLElement>('.autocomplete__item--selected'),
firstItem = $<HTMLElement>('.autocomplete__item:first-of-type'),
lastItem = $<HTMLElement>('.autocomplete__item:last-of-type');
if (inputField !== event.currentTarget) return;
if (inputField && isSearchField(inputField)) {
// Prevent submission of the search field when Enter was hit
if (selected && event.keyCode === 13) event.preventDefault(); // Enter
if (popup.selectedTerm && event.keyCode === 13) event.preventDefault(); // Enter
// Close autocompletion popup when text cursor is outside current tag
if (selectedTerm && firstItem && (event.keyCode === 37 || event.keyCode === 39)) {
if (selectedTerm && (event.keyCode === 37 || event.keyCode === 39)) {
// ArrowLeft || ArrowRight
requestAnimationFrame(() => {
if (isSelectionOutsideCurrentTerm()) removeParent();
if (isSelectionOutsideCurrentTerm()) popup.hide();
});
}
}
if (event.keyCode === 38) changeSelected(lastItem, selected, selected && selected.previousElementSibling); // ArrowUp
if (event.keyCode === 40) changeSelected(firstItem, selected, selected && selected.nextElementSibling); // ArrowDown
if (event.keyCode === 13 || event.keyCode === 27 || event.keyCode === 188) removeParent(); // Enter || Esc || Comma
if (!popup.isActive) return;
if (event.keyCode === 38) popup.selectPrevious(); // ArrowUp
if (event.keyCode === 40) popup.selectNext(); // ArrowDown
if (event.keyCode === 13 || event.keyCode === 27 || event.keyCode === 188) popup.hide(); // Enter || Esc || Comma
if (event.keyCode === 38 || event.keyCode === 40) {
// ArrowUp || ArrowDown
const newSelected = $<HTMLElement>('.autocomplete__item--selected');
if (newSelected?.dataset.value) applySelectedValue(newSelected.dataset.value);
if (popup.selectedTerm) {
applySelectedValue(popup.selectedTerm);
} else {
restoreOriginalValue();
}
event.preventDefault();
}
}
function createItem(list: HTMLUListElement, suggestion: TermSuggestion) {
const item = makeEl('li', {
className: 'autocomplete__item',
});
function findSelectedTerm(targetInput: HTMLInputElement, searchQuery: string): TermContext | null {
if (targetInput.selectionStart === null || targetInput.selectionEnd === null) return null;
item.textContent = suggestion.label;
item.dataset.value = suggestion.value;
mouseMoveThenOver(item, () => {
removeSelected();
item.classList.add('autocomplete__item--selected');
});
item.addEventListener('mouseout', () => {
removeSelected();
});
item.addEventListener('click', () => {
if (!inputField || !item.dataset.value) return;
applySelectedValue(item.dataset.value);
inputField.dispatchEvent(
new CustomEvent('autocomplete', {
detail: {
type: 'click',
label: suggestion.label,
value: suggestion.value,
},
}),
);
});
list.appendChild(item);
}
function createList(parentElement: HTMLElement, suggestions: TermSuggestion[]) {
const list = makeEl('ul', {
className: 'autocomplete__list',
});
suggestions.forEach(suggestion => createItem(list, suggestion));
parentElement.appendChild(list);
}
function createParent(): HTMLElement {
const parent = makeEl('div');
parent.className = 'autocomplete';
if (inputField && inputField.parentElement) {
// Position the parent below the inputfield
parent.style.position = 'absolute';
parent.style.left = `${inputField.offsetLeft}px`;
// Take the inputfield offset, add its height and subtract the amount by which the parent element has scrolled
parent.style.top = `${inputField.offsetTop + inputField.offsetHeight - inputField.parentElement.scrollTop}px`;
}
// We append the parent at the end of body
document.body.appendChild(parent);
return parent;
}
function showAutocomplete(suggestions: TermSuggestion[], fetchedTerm: string, targetInput: HTMLInputElement) {
// Remove old autocomplete suggestions
removeParent();
// Save suggestions in cache
cachedSuggestions[fetchedTerm] = suggestions;
// If the input target is not empty, still visible, and suggestions were found
if (targetInput.value && targetInput.style.display !== 'none' && suggestions.length) {
createList(createParent(), suggestions);
targetInput.addEventListener('keydown', keydownHandler);
}
}
async function getSuggestions(term: string): Promise<TermSuggestion[]> {
// In case source URL was not given at all, do not try sending the request.
if (!inputField?.dataset.acSource) return [];
return await fetch(`${inputField.dataset.acSource}${term}`)
.then(handleError)
.then(response => response.json());
}
function getSelectedTerm(): TermContext | null {
if (!inputField || !originalQuery) return null;
if (inputField.selectionStart === null || inputField.selectionEnd === null) return null;
const selectionIndex = Math.min(inputField.selectionStart, inputField.selectionEnd);
const terms = getTermContexts(originalQuery);
const selectionIndex = Math.min(targetInput.selectionStart, targetInput.selectionEnd);
const terms = getTermContexts(searchQuery);
return terms.find(([range]) => range[0] < selectionIndex && range[1] >= selectionIndex) ?? null;
}
@ -232,29 +114,33 @@ function toggleSearchAutocomplete() {
}
function listenAutocomplete() {
let timeout: number | undefined;
let serverSideSuggestionsTimeout: number | undefined;
let localAc: LocalAutocompleter | null = null;
let localFetched = false;
let isLocalLoading = false;
document.addEventListener('focusin', fetchLocalAutocomplete);
document.addEventListener('focusin', loadAutocompleteFromEvent);
document.addEventListener('input', event => {
removeParent();
fetchLocalAutocomplete(event);
window.clearTimeout(timeout);
popup.hide();
loadAutocompleteFromEvent(event);
window.clearTimeout(serverSideSuggestionsTimeout);
if (!(event.target instanceof HTMLInputElement)) return;
const targetedInput = event.target;
if (localAc !== null && 'ac' in targetedInput.dataset) {
if (!targetedInput.dataset.ac) return;
targetedInput.addEventListener('keydown', keydownHandler);
if (localAc !== null) {
inputField = targetedInput;
let suggestionsCount = 5;
if (isSearchField(inputField)) {
originalQuery = inputField.value;
selectedTerm = getSelectedTerm();
selectedTerm = findSelectedTerm(inputField, originalQuery);
suggestionsCount = 10;
// We don't need to run auto-completion if user is not selecting tag at all
@ -273,62 +159,72 @@ function listenAutocomplete() {
.map(({ name, imageCount }) => ({ label: `${name} (${imageCount})`, value: name }));
if (suggestions.length) {
return showAutocomplete(suggestions, originalTerm, targetedInput);
popup.renderSuggestions(suggestions).showForField(targetedInput);
return;
}
}
const { acMinLength: minTermLength, acSource: endpointUrl } = targetedInput.dataset;
if (!endpointUrl) return;
// Use a timeout to delay requests until the user has stopped typing
timeout = window.setTimeout(() => {
serverSideSuggestionsTimeout = window.setTimeout(() => {
inputField = targetedInput;
originalTerm = inputField.value;
const fetchedTerm = inputField.value;
const { ac, acMinLength, acSource } = inputField.dataset;
if (!ac || !acSource || (acMinLength && fetchedTerm.length < parseInt(acMinLength, 10))) {
return;
}
if (minTermLength && fetchedTerm.length < parseInt(minTermLength, 10)) return;
if (cachedSuggestions[fetchedTerm]) {
showAutocomplete(cachedSuggestions[fetchedTerm], fetchedTerm, targetedInput);
} else {
// inputField could get overwritten while the suggestions are being fetched - use event.target
getSuggestions(fetchedTerm).then(suggestions => {
fetchSuggestions(endpointUrl, fetchedTerm).then(suggestions => {
// inputField could get overwritten while the suggestions are being fetched - use previously targeted input
if (fetchedTerm === targetedInput.value) {
showAutocomplete(suggestions, fetchedTerm, targetedInput);
popup.renderSuggestions(suggestions).showForField(targetedInput);
}
});
}
}, 300);
});
// If there's a click outside the inputField, remove autocomplete
document.addEventListener('click', event => {
if (event.target && event.target !== inputField) removeParent();
if (event.target && event.target !== inputField) popup.hide();
if (inputField && event.target === inputField && isSearchField(inputField) && isSelectionOutsideCurrentTerm()) {
removeParent();
popup.hide();
}
});
function fetchLocalAutocomplete(event: Event) {
function loadAutocompleteFromEvent(event: Event) {
if (!(event.target instanceof HTMLInputElement)) return;
if (!localFetched && event.target.dataset && 'ac' in event.target.dataset) {
const now = new Date();
const cacheKey = `${now.getUTCFullYear()}-${now.getUTCMonth()}-${now.getUTCDate()}`;
if (!isLocalLoading && event.target.dataset.ac) {
isLocalLoading = true;
localFetched = true;
fetch(`/autocomplete/compiled?vsn=2&key=${cacheKey}`, { credentials: 'omit', cache: 'force-cache' })
.then(handleError)
.then(resp => resp.arrayBuffer())
.then(buf => {
localAc = new LocalAutocompleter(buf);
fetchLocalAutocomplete().then(autocomplete => {
localAc = autocomplete;
});
}
}
toggleSearchAutocomplete();
popup.onItemSelected((event: CustomEvent<TermSuggestion>) => {
if (!event.detail || !inputField) return;
const originalSuggestion = event.detail;
applySelectedValue(originalSuggestion.value);
inputField.dispatchEvent(
new CustomEvent('autocomplete', {
detail: Object.assign(
{
type: 'click',
},
originalSuggestion,
),
}),
);
});
}
export { listenAutocomplete };

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@ -0,0 +1,334 @@
import { fetchMock } from '../../../test/fetch-mock.ts';
import {
fetchLocalAutocomplete,
fetchSuggestions,
purgeSuggestionsCache,
SuggestionsPopup,
TermSuggestion,
} from '../suggestions.ts';
import fs from 'fs';
import path from 'path';
import { LocalAutocompleter } from '../local-autocompleter.ts';
import { afterEach } from 'vitest';
import { fireEvent } from '@testing-library/dom';
const mockedSuggestionsEndpoint = '/endpoint?term=';
const mockedSuggestionsResponse = [
{ label: 'artist:assasinmonkey (1)', value: 'artist:assasinmonkey' },
{ label: 'artist:hydrusbeta (1)', value: 'artist:hydrusbeta' },
{ label: 'artist:the sexy assistant (1)', value: 'artist:the sexy assistant' },
{ label: 'artist:devinian (1)', value: 'artist:devinian' },
{ label: 'artist:moe (1)', value: 'artist:moe' },
];
function mockBaseSuggestionsPopup(includeMockedSuggestions: boolean = false): [SuggestionsPopup, HTMLInputElement] {
const input = document.createElement('input');
const popup = new SuggestionsPopup();
document.body.append(input);
popup.showForField(input);
if (includeMockedSuggestions) {
popup.renderSuggestions(mockedSuggestionsResponse);
}
return [popup, input];
}
const selectedItemClassName = 'autocomplete__item--selected';
describe('Suggestions', () => {
let mockedAutocompleteBuffer: ArrayBuffer;
let popup: SuggestionsPopup | undefined;
let input: HTMLInputElement | undefined;
beforeAll(async () => {
fetchMock.enableMocks();
mockedAutocompleteBuffer = await fs.promises
.readFile(path.join(__dirname, 'autocomplete-compiled-v2.bin'))
.then(fileBuffer => fileBuffer.buffer);
});
afterAll(() => {
fetchMock.disableMocks();
});
beforeEach(() => {
purgeSuggestionsCache();
fetchMock.resetMocks();
});
afterEach(() => {
if (input) {
input.remove();
input = undefined;
}
if (popup) {
popup.hide();
popup = undefined;
}
});
describe('SuggestionsPopup', () => {
it('should create the popup container', () => {
[popup, input] = mockBaseSuggestionsPopup();
expect(document.querySelector('.autocomplete')).toBeInstanceOf(HTMLElement);
expect(popup.isActive).toBe(true);
});
it('should be removed when hidden', () => {
[popup, input] = mockBaseSuggestionsPopup();
popup.hide();
expect(document.querySelector('.autocomplete')).not.toBeInstanceOf(HTMLElement);
expect(popup.isActive).toBe(false);
});
it('should render suggestions', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
expect(document.querySelectorAll('.autocomplete__item').length).toBe(mockedSuggestionsResponse.length);
});
it('should initially select first element when selectNext called', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
popup.selectNext();
expect(document.querySelector('.autocomplete__item:first-child')).toHaveClass(selectedItemClassName);
});
it('should initially select last element when selectPrevious called', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
popup.selectPrevious();
expect(document.querySelector('.autocomplete__item:last-child')).toHaveClass(selectedItemClassName);
});
it('should select and de-select items when hovering items over', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
const firstItem = document.querySelector('.autocomplete__item:first-child');
const lastItem = document.querySelector('.autocomplete__item:last-child');
if (firstItem) {
fireEvent.mouseOver(firstItem);
fireEvent.mouseMove(firstItem);
}
expect(firstItem).toHaveClass(selectedItemClassName);
if (lastItem) {
fireEvent.mouseOver(lastItem);
fireEvent.mouseMove(lastItem);
}
expect(firstItem).not.toHaveClass(selectedItemClassName);
expect(lastItem).toHaveClass(selectedItemClassName);
if (lastItem) {
fireEvent.mouseOut(lastItem);
}
expect(lastItem).not.toHaveClass(selectedItemClassName);
});
it('should allow switching between mouse and selection', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
const secondItem = document.querySelector('.autocomplete__item:nth-child(2)');
const thirdItem = document.querySelector('.autocomplete__item:nth-child(3)');
if (secondItem) {
fireEvent.mouseOver(secondItem);
fireEvent.mouseMove(secondItem);
}
expect(secondItem).toHaveClass(selectedItemClassName);
popup.selectNext();
expect(secondItem).not.toHaveClass(selectedItemClassName);
expect(thirdItem).toHaveClass(selectedItemClassName);
});
it('should loop around when selecting next on last and previous on first', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
const firstItem = document.querySelector('.autocomplete__item:first-child');
const lastItem = document.querySelector('.autocomplete__item:last-child');
if (lastItem) {
fireEvent.mouseOver(lastItem);
fireEvent.mouseMove(lastItem);
}
expect(lastItem).toHaveClass(selectedItemClassName);
popup.selectNext();
expect(document.querySelector(`.${selectedItemClassName}`)).toBeNull();
popup.selectNext();
expect(firstItem).toHaveClass(selectedItemClassName);
popup.selectPrevious();
expect(document.querySelector(`.${selectedItemClassName}`)).toBeNull();
popup.selectPrevious();
expect(lastItem).toHaveClass(selectedItemClassName);
});
it('should return selected item value', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
expect(popup.selectedTerm).toBe(null);
popup.selectNext();
expect(popup.selectedTerm).toBe(mockedSuggestionsResponse[0].value);
});
it('should emit an event when item was clicked with mouse', () => {
[popup, input] = mockBaseSuggestionsPopup(true);
let clickEvent: CustomEvent<TermSuggestion> | undefined;
const itemSelectedHandler = vi.fn((event: CustomEvent<TermSuggestion>) => {
clickEvent = event;
});
popup.onItemSelected(itemSelectedHandler);
const firstItem = document.querySelector('.autocomplete__item');
if (firstItem) {
fireEvent.click(firstItem);
}
expect(itemSelectedHandler).toBeCalledTimes(1);
expect(clickEvent?.detail).toEqual(mockedSuggestionsResponse[0]);
});
it('should not emit selection on items without value', () => {
[popup, input] = mockBaseSuggestionsPopup();
popup.renderSuggestions([{ label: 'Option without value', value: '' }]);
const itemSelectionHandler = vi.fn();
popup.onItemSelected(itemSelectionHandler);
const firstItem = document.querySelector('.autocomplete__item:first-child')!;
if (firstItem) {
fireEvent.click(firstItem);
}
expect(itemSelectionHandler).not.toBeCalled();
});
});
describe('fetchSuggestions', () => {
it('should only call fetch once per single term', () => {
fetchSuggestions(mockedSuggestionsEndpoint, 'art');
fetchSuggestions(mockedSuggestionsEndpoint, 'art');
expect(fetch).toHaveBeenCalledTimes(1);
});
it('should be case-insensitive to terms and trim spaces', () => {
fetchSuggestions(mockedSuggestionsEndpoint, 'art');
fetchSuggestions(mockedSuggestionsEndpoint, 'Art');
fetchSuggestions(mockedSuggestionsEndpoint, ' ART ');
expect(fetch).toHaveBeenCalledTimes(1);
});
it('should return the same suggestions from cache', async () => {
fetchMock.mockResolvedValueOnce(new Response(JSON.stringify(mockedSuggestionsResponse), { status: 200 }));
const firstSuggestions = await fetchSuggestions(mockedSuggestionsEndpoint, 'art');
const secondSuggestions = await fetchSuggestions(mockedSuggestionsEndpoint, 'art');
expect(firstSuggestions).toBe(secondSuggestions);
});
it('should parse and return array of suggestions', async () => {
fetchMock.mockResolvedValueOnce(new Response(JSON.stringify(mockedSuggestionsResponse), { status: 200 }));
const resolvedSuggestions = await fetchSuggestions(mockedSuggestionsEndpoint, 'art');
expect(resolvedSuggestions).toBeInstanceOf(Array);
expect(resolvedSuggestions.length).toBe(mockedSuggestionsResponse.length);
expect(resolvedSuggestions).toEqual(mockedSuggestionsResponse);
});
it('should return empty array on server error', async () => {
fetchMock.mockResolvedValueOnce(new Response('', { status: 500 }));
const resolvedSuggestions = await fetchSuggestions(mockedSuggestionsEndpoint, 'unknown tag');
expect(resolvedSuggestions).toBeInstanceOf(Array);
expect(resolvedSuggestions.length).toBe(0);
});
it('should return empty array on invalid response format', async () => {
fetchMock.mockResolvedValueOnce(new Response('invalid non-JSON response', { status: 200 }));
const resolvedSuggestions = await fetchSuggestions(mockedSuggestionsEndpoint, 'invalid response');
expect(resolvedSuggestions).toBeInstanceOf(Array);
expect(resolvedSuggestions.length).toBe(0);
});
});
describe('purgeSuggestionsCache', () => {
it('should clear cached responses', async () => {
fetchMock.mockResolvedValueOnce(new Response(JSON.stringify(mockedSuggestionsResponse), { status: 200 }));
const firstResult = await fetchSuggestions(mockedSuggestionsEndpoint, 'art');
purgeSuggestionsCache();
const resultAfterPurge = await fetchSuggestions(mockedSuggestionsEndpoint, 'art');
expect(fetch).toBeCalledTimes(2);
expect(firstResult).not.toBe(resultAfterPurge);
});
});
describe('fetchLocalAutocomplete', () => {
it('should request binary with date-related cache key', () => {
fetchMock.mockResolvedValue(new Response(mockedAutocompleteBuffer, { status: 200 }));
const now = new Date();
const cacheKey = `${now.getUTCFullYear()}-${now.getUTCMonth()}-${now.getUTCDate()}`;
const expectedEndpoint = `/autocomplete/compiled?vsn=2&key=${cacheKey}`;
fetchLocalAutocomplete();
expect(fetch).toBeCalledWith(expectedEndpoint, { credentials: 'omit', cache: 'force-cache' });
});
it('should return auto-completer instance', async () => {
fetchMock.mockResolvedValue(new Response(mockedAutocompleteBuffer, { status: 200 }));
const autocomplete = await fetchLocalAutocomplete();
expect(autocomplete).toBeInstanceOf(LocalAutocompleter);
});
it('should throw generic server error on failing response', async () => {
fetchMock.mockResolvedValue(new Response('error', { status: 500 }));
expect(() => fetchLocalAutocomplete()).rejects.toThrowError('Received error from server');
});
});
});

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@ -0,0 +1,177 @@
import { makeEl } from './dom.ts';
import { mouseMoveThenOver } from './events.ts';
import { handleError } from './requests.ts';
import { LocalAutocompleter } from './local-autocompleter.ts';
export interface TermSuggestion {
label: string;
value: string;
}
const selectedSuggestionClassName = 'autocomplete__item--selected';
export class SuggestionsPopup {
private readonly container: HTMLElement;
private readonly listElement: HTMLUListElement;
private selectedElement: HTMLElement | null = null;
constructor() {
this.container = makeEl('div', {
className: 'autocomplete',
});
this.listElement = makeEl('ul', {
className: 'autocomplete__list',
});
this.container.appendChild(this.listElement);
}
get selectedTerm(): string | null {
return this.selectedElement?.dataset.value || null;
}
get isActive(): boolean {
return this.container.isConnected;
}
hide() {
this.clearSelection();
this.container.remove();
}
private clearSelection() {
if (!this.selectedElement) return;
this.selectedElement.classList.remove(selectedSuggestionClassName);
this.selectedElement = null;
}
private updateSelection(targetItem: HTMLElement) {
this.clearSelection();
this.selectedElement = targetItem;
this.selectedElement.classList.add(selectedSuggestionClassName);
}
renderSuggestions(suggestions: TermSuggestion[]): SuggestionsPopup {
this.clearSelection();
this.listElement.innerHTML = '';
for (const suggestedTerm of suggestions) {
const listItem = makeEl('li', {
className: 'autocomplete__item',
innerText: suggestedTerm.label,
});
listItem.dataset.value = suggestedTerm.value;
this.watchItem(listItem, suggestedTerm);
this.listElement.appendChild(listItem);
}
return this;
}
private watchItem(listItem: HTMLElement, suggestion: TermSuggestion) {
mouseMoveThenOver(listItem, () => this.updateSelection(listItem));
listItem.addEventListener('mouseout', () => this.clearSelection());
listItem.addEventListener('click', () => {
if (!listItem.dataset.value) {
return;
}
this.container.dispatchEvent(new CustomEvent('item_selected', { detail: suggestion }));
});
}
private changeSelection(direction: number) {
let nextTargetElement: Element | null;
if (!this.selectedElement) {
nextTargetElement = direction > 0 ? this.listElement.firstElementChild : this.listElement.lastElementChild;
} else {
nextTargetElement =
direction > 0 ? this.selectedElement.nextElementSibling : this.selectedElement.previousElementSibling;
}
if (!(nextTargetElement instanceof HTMLElement)) {
this.clearSelection();
return;
}
this.updateSelection(nextTargetElement);
}
selectNext() {
this.changeSelection(1);
}
selectPrevious() {
this.changeSelection(-1);
}
showForField(targetElement: HTMLElement) {
this.container.style.position = 'absolute';
this.container.style.left = `${targetElement.offsetLeft}px`;
let topPosition = targetElement.offsetTop + targetElement.offsetHeight;
if (targetElement.parentElement) {
topPosition -= targetElement.parentElement.scrollTop;
}
this.container.style.top = `${topPosition}px`;
document.body.appendChild(this.container);
}
onItemSelected(callback: (event: CustomEvent<TermSuggestion>) => void) {
this.container.addEventListener('item_selected', callback as EventListener);
}
}
const cachedSuggestions = new Map<string, Promise<TermSuggestion[]>>();
export async function fetchSuggestions(endpoint: string, targetTerm: string): Promise<TermSuggestion[]> {
const normalizedTerm = targetTerm.trim().toLowerCase();
if (cachedSuggestions.has(normalizedTerm)) {
return cachedSuggestions.get(normalizedTerm)!;
}
const promisedSuggestions: Promise<TermSuggestion[]> = fetch(`${endpoint}${targetTerm}`)
.then(handleError)
.then(response => response.json())
.catch(() => {
// Deleting the promised result from cache to allow retrying
cachedSuggestions.delete(normalizedTerm);
// And resolve failed promise with empty array
return [];
});
cachedSuggestions.set(normalizedTerm, promisedSuggestions);
return promisedSuggestions;
}
export function purgeSuggestionsCache() {
cachedSuggestions.clear();
}
export async function fetchLocalAutocomplete(): Promise<LocalAutocompleter> {
const now = new Date();
const cacheKey = `${now.getUTCFullYear()}-${now.getUTCMonth()}-${now.getUTCDate()}`;
return await fetch(`/autocomplete/compiled?vsn=2&key=${cacheKey}`, {
credentials: 'omit',
cache: 'force-cache',
})
.then(handleError)
.then(resp => resp.arrayBuffer())
.then(buf => new LocalAutocompleter(buf));
}