const EventEmitter = require('events') const self = new EventEmitter() self._items = [] self._selectedItemIndex = -1 self._nodes = { search: document.querySelector('#search'), input: document.querySelector('input[type="search"]'), autocomplete: document.querySelector('.autocomplete') } self.getSelectedItem = function () { if (self.getItems() === []) return if (self.getSelectedItemIndex() === -1) { return self.getItems()[0] } else { return self.getItems()[self.getSelectedItemIndex()] } } self.getSelectedItemIndex = function () { return self._selectedItemIndex } self.getItems = function () { return self._items } self.removeAllItems = function () { while (self._nodes.autocomplete.firstChild) { self._nodes.autocomplete.removeChild(self._nodes.autocomplete.firstChild) } self._items = [] self._selectedItemIndex = -1 } self.addItem = function (item) { const listItem = document.createElement('li') listItem.textContent = item.value self._nodes.autocomplete.appendChild(listItem) self._items.push(item) } self._moveSelected = function (shift) { if (self._selectedItemIndex + shift >= self.getItems().length) { self._selectedItemIndex = -1 } else if (self._selectedItemIndex + shift < -1) { self._selectedItemIndex = self.getItems().length - 1 } else { self._selectedItemIndex += shift } for (let i = 0; i < self.getItems().length; i++) { self._nodes.autocomplete.children[i].classList.remove('selected') } if (self._selectedItemIndex >= 0) { self._nodes.autocomplete .children[self._selectedItemIndex].classList.add('selected') } } self._handleItemClick = function (event) { if (!self._nodes.autocomplete.contains(event.target)) return const itemIndex = Array.prototype.indexOf .call(self._nodes.autocomplete.children, event.target) self._selectedItemIndex = itemIndex self.emit('select', self.getSelectedItem()) } self._handleKeydown = function (event) { if (event.key === 'ArrowDown' || event.key === 'ArrowUp') { event.preventDefault() if (event.key === 'ArrowDown') { self._moveSelected(1) } else if (event.key === 'ArrowUp') { self._moveSelected(-1) } } } self._nodes.autocomplete.addEventListener('click', self._handleItemClick) self._nodes.input.addEventListener('keydown', self._handleKeydown) module.exports = self