DrCr/drcr/static/js/combobox.js

/*  DrCr: Web-based double-entry bookkeeping framework
    Copyright (C) 2022–2024  Lee Yingtong Li (RunasSudo)

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

function updateComboboxInputs(elCombobox, elInput) {
	elCombobox.querySelector('ul').querySelectorAll('li').forEach((elLi) => {
		const liText = elLi.querySelector('.combobox-text').innerText;
		if (liText.toLowerCase().startsWith(elInput.value.toLowerCase())) {
			elLi.classList.remove('hidden');
			elLi.classList.add('block');
			
			if (liText == elInput.value) {
				elLi.dataset.selected = 'selected';
			} else {
				elLi.dataset.selected = '';
			}
		} else {
			elLi.classList.remove('block');
			elLi.classList.add('hidden');
			elLi.dataset.selected = '';
		}
	});
}

function initCombobox(elCombobox) {
	const elInput = elCombobox.querySelector('input');
	updateComboboxInputs(elCombobox, elInput);
	
	// Update combobox options on input
	elInput.addEventListener('input', (evt) => {
		updateComboboxInputs(elCombobox, elInput);
	});
	
	// Open dropdown on click button
	elCombobox.querySelector('button').addEventListener('click', (evt) => {
		elInput.focus();
	});
	
	// Update combobox value on select
	elCombobox.querySelector('ul').querySelectorAll('li').forEach((elLi) => {
		elLi.addEventListener('mousedown', (evt) => {
			const liText = elLi.querySelector('.combobox-text').innerText;
			elInput.value = liText;
			updateComboboxInputs(elCombobox, elInput);
		});
	});
}

// Init comboboxes
document.querySelectorAll('.combobox').forEach(initCombobox);