const $ = document.querySelector.bind(document);
const $$ = document.querySelectorAll.bind(document);

function scheduleCCall(f, ms, ...args) {
	const func = UTF8ToString(f);
	return setTimeout(() => Module[`_${func}`](...args), ms);
}

function toCString(str) { // caller must free
	if (!str) return 0;

	const size = lengthBytesUTF8(str) + 1;
	const ptr = _malloc(size);
	stringToUTF8(str, ptr, size);
	return ptr;
}

function elemGetContent(sel) { // caller must free
	return toCString($(UTF8ToString(sel)).textContent);
}

function elemSetContent(sel, str) {
	$(UTF8ToString(sel)).textContent = str ? UTF8ToString(str) : '';
}

function elemSetValue(sel, str) {
	$(UTF8ToString(sel)).value = str ? UTF8ToString(str) : '';
}

function elemHasClass(sel, c) {
	return $(UTF8ToString(sel)).classList.contains(UTF8ToString(c));
}

function elemAddClass(sel, c) {
	$(UTF8ToString(sel)).classList.add(UTF8ToString(c));
}

function elemRemoveClass(sel, c) {
	$(UTF8ToString(sel)).classList.remove(UTF8ToString(c));
}

function elemToggleClass(sel, c) {
	$(UTF8ToString(sel)).classList.toggle(UTF8ToString(c));
}

function elemSetUniqClass(sel, c, sel_set) {
	selstr = sel && UTF8ToString(sel);
	cstr = UTF8ToString(c);
	$$(UTF8ToString(sel_set)).forEach(e => e.classList[
		sel && e.matches(selstr) ? 'add' : 'remove'](cstr));
}

function elemScrollToBottom(sel) {
	const e = $(UTF8ToString(sel));
	e.scrollTop = e.scrollHeight;
}

function elemAppendElemv(sel, elemc, elemv, off_ns, off_name, off_content,
	off_n_attrs, off_attr_names, off_attr_vals) {
	const target = $(UTF8ToString(sel));

	for (let ptr = elemv; ptr < elemv + 4*elemc; ptr += 4) {
		const struct = HEAP32[ptr>>2];

		const nsptr = HEAP32[(struct + off_ns)>>2];
		const name = UTF8ToString(HEAP32[(struct + off_name)>>2]);
		const e = nsptr ?
			document.createElementNS(UTF8ToString(nsptr), name) :
			document.createElement(name);

		const n_attrs = HEAP32[(struct + off_n_attrs)>>2];
		if (n_attrs) {
			const attr_names =
				HEAP32[(struct + off_attr_names)>>2];
			const attr_vals = HEAP32[(struct + off_attr_vals)>>2];
			for (let i = 0; i < n_attrs; ++i)
				e.setAttribute(
					UTF8ToString(
						HEAP32[(attr_names + i*4)>>2]),
					UTF8ToString(
						HEAP32[(attr_vals + i*4)>>2]));
		}

		const content = HEAP32[(struct + off_content)>>2];
		if (content) e.textContent = UTF8ToString(content);

		target.appendChild(e);
	}
}

function promptHandle(command, data) {
	const str_c = toCString(command);
	const str_d = data && toCString(data);
	_prompt_handle(str_c, str_d);

	_free(str_c);
	if (str_d) _free(str_d);
}

function readOpt(opt) { // caller must free
	return toCString(localStorage.getItem(UTF8ToString(opt)));
}

function storeOpt(opt, val) {
	localStorage.setItem(UTF8ToString(opt), UTF8ToString(val));
}

function boatAfloat() {
	if (document.readyState === 'loading')
		document.addEventListener('DOMContentLoaded', () => _init());
	else
		_init();
}

function flipControls() {
	const enabled = $('#main').classList.toggle('right-controls');
	$('#flip-controls-button').textContent = enabled ? '\u2190' : '\u2192';
}

document.addEventListener('DOMContentLoaded', () => {
	let f;

	f = e => e.target.dataset.command.split(';').forEach(x =>
		promptHandle(...x.split(':', 2)));
	$$('[data-command]').forEach(x => x.addEventListener('click', f));

	f = e => _set_opt(toCString(e.target.dataset.opt),
		toCString(e.target.value));
	$$('[data-opt]').forEach(x => x.addEventListener('change', f));

	$('#flip-controls-button').addEventListener('click', flipControls);

	f = e => $(`#${e.target.dataset.modal}`).style.display = 'block';
	$$('[data-modal]').forEach(x => x.addEventListener('click', f));
	f = e => {
		if (e.target === e.currentTarget)
			e.target.style.display = 'none';
	};
	$$('.modal').forEach(x => x.addEventListener('click', f));
});

document.addEventListener('keydown', e => {
	if (e.altKey || e.ctrlKey || e.metaKey || e.target.type == 'text')
		return;

	if (isFinite(e.key))
		promptHandle('append', e.key);
	else if (e.key == 'Enter')
		promptHandle('submit');
	else if (e.key == 'Backspace')
		promptHandle('backspace');
	else if (e.key == 'c')
		promptHandle('clear');
	else if (e.key == 'r')
		promptHandle('rem');
	else if (e.key == 'u')
		promptHandle('undo');
});