table-wrapper.js

import '../colors/colors.js';
import '../scroll-wrapper/scroll-wrapper.js';
import { css, html, LitElement, nothing } from 'lit';
import { cssSizes } from '../inputs/input-checkbox.js';
import { getComposedParent } from '../../helpers/dom.js';
import { PageableMixin } from '../paging/pageable-mixin.js';
import ResizeObserver from 'resize-observer-polyfill/dist/ResizeObserver.es.js';
import { RtlMixin } from '../../mixins/rtl/rtl-mixin.js';
import { SelectionMixin } from '../selection/selection-mixin.js';

export const tableStyles = css`
	.d2l-table {
		border-collapse: separate; /* needed to override reset stylesheets */
		border-spacing: 0;
		font-size: 0.8rem;
		font-weight: 400;
		width: 100%;
	}

	.d2l-table > tbody,
	.d2l-table > tfoot {
		background-color: #ffffff;
	}

	/* all cells */
	.d2l-table > * > tr > * {
		border-bottom: var(--d2l-table-border);
		font-weight: inherit;
		height: var(--d2l-table-cell-height);
		padding: var(--d2l-table-cell-padding);
		text-align: left;
		vertical-align: middle;
	}
	d2l-table-wrapper[dir="rtl"] .d2l-table > * > tr > * {
		text-align: right;
	}
	d2l-table-wrapper d2l-button-icon {
		--d2l-button-icon-min-height: calc(var(--d2l-table-cell-overall-height) - 2 * var(--d2l-table-cell-col-sort-button-size-offset));
		--d2l-button-icon-min-width: calc(var(--d2l-table-cell-overall-height) - 2 * var(--d2l-table-cell-col-sort-button-size-offset));
	}
	d2l-table-wrapper d2l-dropdown-context-menu {
		--d2l-dropdown-context-menu-min-height: calc(var(--d2l-table-cell-overall-height) - 2 * var(--d2l-table-cell-col-sort-button-size-offset));
		--d2l-dropdown-context-menu-min-width: calc(var(--d2l-table-cell-overall-height) - 2 * var(--d2l-table-cell-col-sort-button-size-offset));
	}

	/* once we only support browsers that support :has the section below can be removed up until @supports */
	.d2l-table .d2l-checkbox,
	.d2l-table d2l-input-checkbox,
	.d2l-table d2l-selection-select-all,
	.d2l-table d2l-selection-input {
		margin-block: calc(0.5 * (var(--d2l-table-cell-height) - ${cssSizes.inputBoxSize}rem));
	}
	.d2l-table > * > tr.d2l-table-selected-first d2l-input-checkbox,
	.d2l-table > * > tr.d2l-table-selected-first d2l-selection-input,
	.d2l-table > * > tr.d2l-table-selected-first .d2l-checkbox {
		margin-bottom: calc(0.5 * (var(--d2l-table-cell-height) - ${cssSizes.inputBoxSize}rem));
		margin-top: calc(0.5 * (var(--d2l-table-cell-height) - ${cssSizes.inputBoxSize}rem) - 1px);
	}
	@supports selector(:has(a, b)) {
		.d2l-table > * > tr > :has(.d2l-checkbox),
		.d2l-table > * > tr > :has(d2l-selection-select-all),
		.d2l-table > * > tr > :has(d2l-input-checkbox),
		.d2l-table > * > tr > :has(d2l-selection-input) {
			padding-block: calc(0.5 * (var(--d2l-table-cell-overall-height) - ${cssSizes.inputBoxSize}rem));
		}
		.d2l-table > * > tr.d2l-table-selected-first > :has(.d2l-checkbox),
		.d2l-table > * > tr.d2l-table-selected-first > :has(d2l-input-checkbox),
		.d2l-table > * > tr.d2l-table-selected-first > :has(d2l-selection-input) {
			padding-bottom: calc(0.5 * (var(--d2l-table-cell-overall-height) - ${cssSizes.inputBoxSize}rem));
			padding-top: calc(0.5 * (var(--d2l-table-cell-overall-height) - ${cssSizes.inputBoxSize}rem) - 1px);
		}
	}

	/* default cells */
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table > * > tr > *,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table > * > tr > .d2l-table-cell-first {
		border-right: var(--d2l-table-border);
	}
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table > * > tr > *,
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table > * > tr > .d2l-table-cell-first {
		border-left: var(--d2l-table-border);
	}
	d2l-table-wrapper[type="default"] .d2l-table-row-first > * {
		border-top: var(--d2l-table-border); /* add top border to default first row */
	}

	/* header cells */
	.d2l-table > thead > tr > th,
	.d2l-table > * > tr.d2l-table-header > th,
	.d2l-table > * > tr[header] > th {
		background-color: var(--d2l-table-header-background-color);
		font-size: 0.7rem;
		line-height: 0.9rem;
	}

	/* sortable header cells */
	d2l-table-col-sort-button {
		vertical-align: middle;
	}
	d2l-table-col-sort-button:not(:only-child) {
		--d2l-table-col-sort-button-additional-padding-inline-end: 0px; /* stylelint-disable-line length-zero-no-unit */
		--d2l-table-col-sort-button-additional-padding-inline-start: 0px; /* stylelint-disable-line length-zero-no-unit */
	}

	/* TODO: once we only support browsers that support :has the section below can be removed up until @supports */
	.d2l-table th.d2l-table-header-col-sortable {
		height: calc(var(--d2l-table-cell-overall-height) - var(--d2l-table-cell-col-sort-button-size-offset));
		padding-block: var(--d2l-table-cell-col-sort-button-size-offset) 0;
		padding-inline: var(--d2l-table-cell-col-sort-button-size-offset) 0;
	}
	.d2l-table th.d2l-table-header-col-sortable-siblings d2l-table-col-sort-button {
		--d2l-table-col-sort-button-width: unset;
	}

	@supports selector(:has(a, b)) {
		.d2l-table > * > tr > th:has(d2l-table-col-sort-button) {
			height: calc(var(--d2l-table-cell-overall-height) - var(--d2l-table-cell-col-sort-button-size-offset));
			padding-block: var(--d2l-table-cell-col-sort-button-size-offset) 0;
			padding-inline: var(--d2l-table-cell-col-sort-button-size-offset) 0;
		}
		.d2l-table th:has(d2l-table-col-sort-button:not(:only-child)) d2l-table-col-sort-button {
			--d2l-table-col-sort-button-width: unset;
		}
	}

	/* has at least one d2l-table-col-sort-button with [nosort], does not have d2l-table-col-sort-button without nosort */
	.d2l-table th d2l-table-col-sort-button[nosort] ~ :last-child {
		padding-inline-end: calc(0.6rem + 18px);
	}
	.d2l-table th d2l-table-col-sort-button:not([nosort]) ~ :last-child,
	.d2l-table th d2l-table-col-sort-button:last-child:not([nosort]) {
		padding-inline-end: unset;
	}

	/* border radiuses */
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table-row-first > .d2l-table-cell-first,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table-row-first > .d2l-table-cell-last {
		border-top-left-radius: var(--d2l-table-border-radius);
	}
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table-row-first > .d2l-table-cell-last,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table-row-first > .d2l-table-cell-first {
		border-top-right-radius: var(--d2l-table-border-radius);
	}
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table-row-last > .d2l-table-cell-first,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table-row-last > .d2l-table-cell-last {
		border-bottom-left-radius: var(--d2l-table-border-radius);
	}
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table-row-last > .d2l-table-cell-last,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table-row-last > .d2l-table-cell-first {
		border-bottom-right-radius: var(--d2l-table-border-radius);
	}

	/* selected rows */
	.d2l-table > tbody > tr[selected] {
		background-color: var(--d2l-table-row-background-color-selected);
	}
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table > tbody > tr[selected] > .d2l-table-cell-last,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table > tbody > tr[selected] > .d2l-table-cell-first {
		border-right-color: var(--d2l-table-row-border-color-selected);
	}
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table > tbody > tr[selected] > .d2l-table-cell-first,
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table > tbody > tr[selected] > .d2l-table-cell-last {
		border-left-color: var(--d2l-table-row-border-color-selected);
	}
	.d2l-table > tbody > tr[selected] > *,
	.d2l-table > * > tr.d2l-table-selected-previous > * {
		border-bottom-color: var(--d2l-table-row-border-color-selected);
	}
	.d2l-table > * > tr.d2l-table-selected-first > * {
		border-top: 1px solid var(--d2l-table-row-border-color-selected);
		padding: var(--d2l-table-cell-padding-alt);
	}

	/* no-column-border */
	d2l-table-wrapper[type="default"][no-column-border]:not([dir="rtl"]) .d2l-table > tbody > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table[no-column-border] > tbody > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"][no-column-border]:not([dir="rtl"]) .d2l-table > thead > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"]:not([dir="rtl"]) .d2l-table[no-column-border] > thead > tr > *:not(.d2l-table-cell-last) {
		border-right: none;
	}
	d2l-table-wrapper[type="default"][no-column-border][dir="rtl"] .d2l-table > tbody > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table[no-column-border] > tbody > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"][no-column-border][dir="rtl"] .d2l-table > thead > tr > *:not(.d2l-table-cell-last),
	d2l-table-wrapper[type="default"][dir="rtl"] .d2l-table[no-column-border] > thead > tr > *:not(.d2l-table-cell-last) {
		border-left: none;
	}

	/* sticky-headers */

	/* all sticky cells */
	d2l-table-wrapper[sticky-headers] .d2l-table > * > tr > .d2l-table-sticky-cell,
	d2l-table-wrapper[sticky-headers] .d2l-table > * > tr > [sticky] {
		position: -webkit-sticky;
		position: sticky;
		z-index: 1;
	}
	d2l-table-wrapper:not([dir="rtl"])[sticky-headers] .d2l-table > * > tr > .d2l-table-sticky-cell,
	d2l-table-wrapper:not([dir="rtl"])[sticky-headers] .d2l-table > * > tr > [sticky] {
		left: 0;
	}
	d2l-table-wrapper[dir="rtl"][sticky-headers] .d2l-table > * > tr > .d2l-table-sticky-cell,
	d2l-table-wrapper[dir="rtl"][sticky-headers] .d2l-table > * > tr > [sticky] {
		right: 0;
	}

	/* non-header sticky cells */
	d2l-table-wrapper[sticky-headers] .d2l-table > * > tr:not([selected]) {
		background-color: inherit; /* white background so sticky cells layer on top of non-sticky cells */
	}
	d2l-table-wrapper[sticky-headers] .d2l-table > tbody > tr:not([header]):not(.d2l-table-header) > .d2l-table-sticky-cell,
	d2l-table-wrapper[sticky-headers] .d2l-table > tbody > tr:not([header]):not(.d2l-table-header) > [sticky] {
		background-color: inherit;
	}

	/* all header cells */
	d2l-table-wrapper[sticky-headers] .d2l-table > thead > tr > th,
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr.d2l-table-header > *,
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr[header] > * {
		position: -webkit-sticky;
		position: sticky;
		z-index: 2;
	}

	/* header cells that are also sticky */
	d2l-table-wrapper[sticky-headers] .d2l-table > thead > tr > th.d2l-table-sticky-cell,
	d2l-table-wrapper[sticky-headers] .d2l-table > thead > tr > th[sticky],
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr.d2l-table-header > .d2l-table-sticky-cell,
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr.d2l-table-header > [sticky],
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr[header] > .d2l-table-sticky-cell,
	d2l-table-wrapper[sticky-headers]:not([sticky-headers-scroll-wrapper]) .d2l-table > * > tr[header] > [sticky] {
		z-index: 4;
	}

	/* first column that's sticky: offset by size of border-radius so top/bottom border doesn't show through (default style only) */
	d2l-table-wrapper[sticky-headers][type="default"]:not([dir="rtl"]) .d2l-table > * > tr > .d2l-table-sticky-cell.d2l-table-cell-first,
	d2l-table-wrapper[sticky-headers][type="default"]:not([dir="rtl"]) .d2l-table > * > tr > [sticky].d2l-table-cell-first {
		left: var(--d2l-table-border-radius-sticky-offset, 0);
	}
	d2l-table-wrapper[sticky-headers][type="default"][dir="rtl"] .d2l-table > * > tr > .d2l-table-sticky-cell.d2l-table-cell-first,
	d2l-table-wrapper[sticky-headers][type="default"][dir="rtl"] .d2l-table > * > tr > [sticky].d2l-table-cell-first {
		right: var(--d2l-table-border-radius-sticky-offset, 0);
	}

	/* sticky + scroll-wrapper */
	d2l-table-wrapper[sticky-headers][sticky-headers-scroll-wrapper] .d2l-table {
		display: block;
	}

	d2l-table-wrapper[sticky-headers][sticky-headers-scroll-wrapper] .d2l-table > thead {
		display: block;
		position: sticky;
		top: calc(var(--d2l-table-sticky-top, 0px) + var(--d2l-table-border-radius-sticky-offset, 0px));
		z-index: 2;
	}

	d2l-table-wrapper[sticky-headers][sticky-headers-scroll-wrapper] .d2l-table > tbody {
		display: block;
	}

	[data-popover-count] {
		z-index: 6 !important; /* if opened above, we want to stack on top of sticky table-controls */
	}
`;

const SELECTORS = {
	headers: 'tr.d2l-table-header, tr[header], thead tr',
	items: ':not(thead) > tr:not(.d2l-table-header):not([header])',
};

/**
 * Wraps a native <table> element, providing styling and scroll buttons for overflow.
 * @slot - Content to wrap
 * @slot controls - Slot for `d2l-table-controls` to be rendered above the table
 * @slot pager - Slot for `d2l-pager-load-more` to be rendered below the table
 */
export class TableWrapper extends RtlMixin(PageableMixin(SelectionMixin(LitElement))) {

	static get properties() {
		return {
			/**
			 * Hides the column borders on "default" table type
			 * @type {boolean}
			 */
			noColumnBorder: {
				attribute: 'no-column-border',
				reflect: true,
				type: Boolean
			},
			/**
			 * Whether the header row is sticky. Useful for long tables to "stick" the header row in place as the user scrolls.
			 * @type {boolean}
			 */
			stickyHeaders: {
				attribute: 'sticky-headers',
				reflect: true,
				type: Boolean
			},
			/**
			 * When used in combo with `sticky-headers`, whether to additionally wrap the table in a scroll-wrapper. Requires sticky headers to be in a separate thead.
			 * @type {boolean}
			 */
			stickyHeadersScrollWrapper: {
				attribute: 'sticky-headers-scroll-wrapper',
				reflect: true,
				type: Boolean
			},
			/**
			 * Type of table style to apply. The "light" style has fewer borders and tighter padding.
			 * @type {'default'|'light'}
			 */
			type: {
				reflect: true,
				type: String
			},
			_controlsScrolled: { state: true }
		};
	}

	static get styles() {
		return css`
			:host {
				--d2l-table-border: 1px solid var(--d2l-table-border-color);
				--d2l-table-border-color: var(--d2l-color-mica);
				--d2l-table-border-radius: 0.3rem;
				--d2l-table-border-radius-sticky-offset: calc(1px - var(--d2l-table-border-radius));
				--d2l-table-cell-overall-height: 46px;
				--d2l-table-cell-height: calc(var(--d2l-table-cell-overall-height) - 2 * var(--d2l-table-cell-padding));
				--d2l-table-cell-padding: 0.7rem;
				--d2l-table-cell-padding-alt: calc(0.7rem - 1px) 0.7rem 0.7rem 0.7rem;
				--d2l-table-cell-col-sort-button-size-offset: 4px;
				--d2l-table-header-background-color: var(--d2l-color-regolith);
				--d2l-table-row-border-color-selected: var(--d2l-color-celestine);
				--d2l-table-row-background-color-selected: var(--d2l-color-celestine-plus-2);
				display: block;
				width: 100%;
			}
			:host([hidden]) {
				display: none;
			}
			:host([type="light"]) {
				--d2l-table-border-radius: 0rem; /* stylelint-disable-line length-zero-no-unit */
				--d2l-table-border-radius-sticky-offset: 0rem; /* stylelint-disable-line length-zero-no-unit */
				--d2l-table-border-color: var(--d2l-color-gypsum);
				--d2l-table-header-background-color: #ffffff;
			}
			:host([sticky-headers]) {
				--d2l-table-controls-shadow-display: none;
			}
			.d2l-sticky-headers-backdrop {
				position: sticky;
				top: calc(var(--d2l-table-sticky-top, 0px) + var(--d2l-table-border-radius));
				width: 100%;
				z-index: 2; /* Must sit under d2l-table sticky-headers but over sticky columns and regular cells */
			}
			.d2l-sticky-headers-backdrop::after {
				background-color: var(--d2l-table-controls-background-color, white);
				bottom: 0;
				content: "";
				position: absolute;
				top: calc(-7px - var(--d2l-table-border-radius)); /* 6px for the d2l-table-controls margin-bottom, 1px overlap to fix zoom issues */
				width: 100%;
			}
			slot[name="pager"]::slotted(*) {
				margin-top: 12px;
			}
		`;
	}

	constructor() {
		super();
		this.noColumnBorder = false;
		this.stickyHeaders = false;
		this.stickyHeadersScrollWrapper = false;
		this.type = 'default';

		this._controls = null;
		this._controlsMutationObserver = null;
		this._controlsScrolled = false;
		this._controlsScrolledMutationObserver = null;
		this._table = null;
		this._tableIntersectionObserver = null;
		this._tableMutationObserver = null;
		this._tableScrollers = {};
	}

	connectedCallback() {
		super.connectedCallback();

		this.addEventListener('d2l-dropdown-open', this._handlePopoverOpen);
		this.addEventListener('d2l-dropdown-close', this._handlePopoverClose);
		this.addEventListener('d2l-tooltip-show', this._handlePopoverOpen);
		this.addEventListener('d2l-tooltip-hide', this._handlePopoverClose);

	}

	disconnectedCallback() {
		super.disconnectedCallback();

		this.removeEventListener('d2l-dropdown-open', this._handlePopoverOpen);
		this.removeEventListener('d2l-dropdown-close', this._handlePopoverClose);
		this.removeEventListener('d2l-tooltip-show', this._handlePopoverOpen);
		this.removeEventListener('d2l-tooltip-hide', this._handlePopoverClose);

		this._controlsMutationObserver?.disconnect();
		this._controlsScrolledMutationObserver?.disconnect();
		this._tableMutationObserver?.disconnect();
		this._tableIntersectionObserver?.disconnect();
		this._tableResizeObserver?.disconnect();
	}

	render() {
		const slot = html`<slot @slotchange="${this._handleSlotChange}"></slot>`;
		const useScrollWrapper = this.stickyHeadersScrollWrapper || !this.stickyHeaders;
		return html`
			<slot name="controls" @slotchange="${this._handleControlsSlotChange}"></slot>
			${this.stickyHeaders && this._controlsScrolled ? html`<div class="d2l-sticky-headers-backdrop"></div>` : nothing}
			${useScrollWrapper ? html`<d2l-scroll-wrapper .customScrollers="${this._tableScrollers}">${slot}</d2l-scroll-wrapper>` : slot}
			${this._renderPagerContainer()}
		`;
	}

	updated(changedProperties) {
		super.updated(changedProperties);

		// hack: grades/groups/outcomes in the LE use this CSS class on the
		// body to apply special CSS to the page when tables are sticky
		// Ideally they should be adding this class to the body.
		if (changedProperties.has('stickyHeaders')) {
			if (this.stickyHeaders) {
				document.body.classList.add('d2l-table-sticky-headers');
			}
		}
	}

	_applyClassNames() {
		if (!this._table) return;

		// offsetParent causes reflow/paint so do them all at once
		const rows = Array.from(this._table.rows);
		let firstRow = null;
		let lastRow = null;
		rows.forEach((r) => {
			if (r.offsetParent === null) return;
			firstRow = firstRow || r;
			lastRow = r;
		});

		let prevRow = null;
		let skipFirst = 0;
		rows.forEach((r) => {
			const isHeader = r.parentNode.tagName === 'THEAD' || r.classList.contains('d2l-table-header') || r.hasAttribute('header');
			const isSelected = r.hasAttribute('selected');

			let firstNonHeaderRow = !isHeader;
			if (prevRow) {
				const isPrevRowHeader = prevRow.parentNode.tagName === 'THEAD' || prevRow.hasAttribute('header');
				firstNonHeaderRow = firstNonHeaderRow && isPrevRowHeader;
				prevRow.classList.toggle('d2l-table-selected-previous', isSelected && !isPrevRowHeader);
			}

			r.classList.toggle('d2l-table-row-first', r === firstRow);
			r.classList.toggle('d2l-table-row-last', r === lastRow);
			r.classList.toggle('d2l-table-selected-first', firstNonHeaderRow && isSelected);
			if (r === lastRow) {
				r.classList.remove('d2l-table-selected-previous');
			}

			Array.from(r.cells).forEach((c, index) => {
				if (isHeader && !CSS.supports('selector(:has(a, b))')) this._checkSiblingSortableCells(c);
				c.classList.toggle('d2l-table-cell-first', index === 0 && skipFirst === 0);
				if (index === 0 && skipFirst === 0 && c.hasAttribute('rowspan')) {
					skipFirst = parseInt(c.getAttribute('rowspan'));
				}
				c.classList.toggle('d2l-table-cell-last', index === r.cells.length - 1);
			});

			prevRow = r;
			skipFirst = Math.max(0, --skipFirst);
		});
	}

	_checkSiblingSortableCells(c) {
		const hasColSortButton = c.querySelector('d2l-table-col-sort-button');
		if (!hasColSortButton) return;
		c.classList.toggle('d2l-table-header-col-sortable', true);
		c.classList.toggle('d2l-table-header-col-sortable-siblings', c.childElementCount > 1);

		const hasSorted = c.querySelector('d2l-table-col-sort-button:not([nosort])');
		c.classList.toggle('d2l-table-header-col-sortable-no-sorted', !hasSorted);
	}

	_getItemByIndex(index) {
		return this._getItems()[index];
	}

	_getItems() {
		return this._table?.querySelectorAll(SELECTORS.items) || [];
	}

	_getItemShowingCount() {
		return this._getItems().length;
	}

	async _handleControlsChange() {
		if (this._controls) {
			await this._controls.updateComplete;
			await new Promise(resolve => requestAnimationFrame(resolve));
		}

		this._handleControlsScrolledChange();
		this._updateStickyTops();
	}

	_handleControlsScrolledChange() {
		this._controlsScrolled = this._controls?._scrolled;
	}

	_handleControlsSlotChange(e) {
		this._controls = e.target.assignedNodes({ flatten: true })[0];

		this._registerMutationObserver('_controlsMutationObserver', this._handleControlsChange.bind(this), this._controls, {
			attributes: true,
			attributeFilter: ['hidden', 'no-sticky'],
		});
		this._registerMutationObserver('_controlsScrolledMutationObserver', this._handleControlsScrolledChange.bind(this), this._controls, {
			attributes: true,
			attributeFilter: ['_scrolled'],
		});

		this._handleControlsChange();
	}

	_handlePopoverClose(e) {
		this._updateStickyAncestor(e.target, false);
	}

	_handlePopoverOpen(e) {
		this._updateStickyAncestor(e.target, true);
	}

	_handleSlotChange(e) {
		this._table = e.target.assignedNodes({ flatten: true }).find(
			node => (node.nodeType === Node.ELEMENT_NODE && node.tagName === 'TABLE' && node.classList.contains('d2l-table'))
		);
		this._tableScrollers = (this.stickyHeadersScrollWrapper && this.stickyHeaders) ? {
			primary: this._table?.querySelector('tbody'),
			secondary: this._table?.querySelector('thead'),
		} : {};

		// observes mutations to <table>'s direct children and also
		// its subtree (rows or cells added/removed to any descendant)
		this._registerMutationObserver('_tableMutationObserver', this._handleTableChange.bind(this), this._table, {
			attributeFilter: ['selected'],
			childList: true,
			subtree: true
		});
		this._tableResizeObserver?.disconnect();

		if (!this._table) return;

		// observes when visibility of <table> changes to catch cases
		// where table is initially hidden (which would cause first/last
		// row classes to be unset) but then becomes shown
		if (typeof(IntersectionObserver) === 'function') {
			if (this._tableIntersectionObserver === null) {
				this._tableIntersectionObserver = new IntersectionObserver((entries) => {
					entries.forEach((entry) => {
						if (entry.isIntersecting) {
							this._handleTableChange();
						}
					});
				});
			} else {
				this._tableIntersectionObserver.disconnect();
			}
			this._tableIntersectionObserver.observe(this._table);
		}

		if (!this._tableResizeObserver) this._tableResizeObserver = new ResizeObserver(() => this._syncColumnWidths());
		this._tableResizeObserver.observe(this._table);

		this._handleTableChange();
	}

	async _handleTableChange(mutationRecords) {
		const flag = window.D2L?.LP?.Web?.UI?.Flags.Flag('table-update-filter-GAUD-6955', true) ?? true;
		const updates = { count: true, classNames: true, sticky: true, syncWidths: true };
		if (flag) {
			if (mutationRecords) {
				for (const key in updates) updates[key] = false;
				for (const { type, removedNodes, addedNodes, target, attributeName } of mutationRecords) {
					if (type === 'attributes') {
						updates.classNames = attributeName === 'selected';
						continue;
					}

					updates.sticky ||= target.matches(SELECTORS.headers);
					const affectedNodes = [...removedNodes, ...addedNodes];
					for (const node of affectedNodes) {
						if (!(node instanceof Element)) continue;
						updates.classNames ||= node.matches('tr, td, th');
						updates.syncWidths ||= node.matches('tr');
						updates.sticky ||= node.matches(SELECTORS.headers);
						updates.count ||= node.matches(SELECTORS.items);
					}
				}
			}
		}

		await new Promise(resolve => requestAnimationFrame(resolve));

		if (updates.count) this._updateItemShowingCount();
		if (updates.classNames) this._applyClassNames();
		if (updates.syncWidths) this._syncColumnWidths();
		if (updates.sticky) this._updateStickyTops();
	}

	_registerMutationObserver(observerName, callback, target, options) {
		if (this[observerName]) {
			this[observerName].disconnect();
		} else if (target) {
			this[observerName] = new MutationObserver(callback);
		}
		if (target) this[observerName].observe(target, options);
	}

	_syncColumnWidths() {
		if (!this._table || !this.stickyHeaders || !this.stickyHeadersScrollWrapper) return;

		const head = this._table.querySelector('thead');
		const body = this._table.querySelector('tbody');
		if (!head || !body) return;

		const candidateRowHeadCells = [];

		// Max length of one of our body rows, which we'll try to map to our candidate head cells.
		const maxRowBodyLength = Math.max(...([...body.rows].map(row => row.cells.length)));

		const headCellsMap = [];
		for (let i = 0; i < head.rows.length; i++) {
			headCellsMap[i] = [];
		}

		// Build a map of which cells "exist" in each head row so we can pick out
		// a candidate in each column to sync widths with.
		for (let rowIndex = 0; rowIndex < head.rows.length; rowIndex++) {
			const rowMap = headCellsMap[rowIndex];

			let spanOffset = 0;
			for (let colIndex = 0; colIndex < maxRowBodyLength; colIndex++) {
				if (rowMap[colIndex] === null) {
					spanOffset++;
					continue;
				}

				const cell = head.rows[rowIndex].cells[colIndex - spanOffset];
				rowMap[colIndex] = cell;

				if (!cell) continue;

				const colSpan = cell.colSpan;
				const rowSpan = cell.rowSpan;

				for (let offset = 1; offset < colSpan; offset++) {
					rowMap[colIndex + offset] = null;
				}

				for (let offset = 1; offset < rowSpan; offset++) {
					headCellsMap[rowIndex + offset][colIndex] = null;
				}
			}
		}

		// Pick out a single head cell for each column to sync widths.
		for (let i = 0; i < maxRowBodyLength; i++) {
			let candidateCell;
			for (const rowMap of headCellsMap) {
				const cell = rowMap[i];

				if (cell && cell.colSpan === 1) {
					candidateCell = cell;
					break;
				}
			}

			// This does not support heads without at least one single-column
			// spanning cell in each column.
			if (!candidateCell) return;

			candidateRowHeadCells[i] = candidateCell;
		}

		// Pick the body row with the most cells (and no colspans) to measure against
		const candidateRowBody = [...body.rows].find(row => {
			return row.cells.length === maxRowBodyLength
				&& ![...row.cells].find(cell => cell.colSpan > 1);
		});

		if (candidateRowHeadCells.length === 0 || !candidateRowBody) return;

		let candidateRowBodyLength = 0;
		for (const cell of candidateRowBody.cells) {
			candidateRowBodyLength += cell.colSpan;
		}

		if (candidateRowHeadCells.length !== candidateRowBodyLength) return;

		for (let i = 0; i < candidateRowHeadCells.length; i++) {
			const headCell = candidateRowHeadCells[i];
			const headStyle = getComputedStyle(headCell);

			const bodyCell = candidateRowBody.cells[i];
			const bodyStyle = getComputedStyle(bodyCell);

			if (headCell.clientWidth > bodyCell.clientWidth) {
				const headOverallWidth = parseFloat(headStyle.width) + parseFloat(headStyle.paddingLeft) + parseFloat(headStyle.paddingRight);
				bodyCell.style.minWidth = `${headOverallWidth - parseFloat(bodyStyle.paddingLeft) - parseFloat(bodyStyle.paddingRight)}px`;
			} else if (headCell.clientWidth < bodyCell.clientWidth) {
				const bodyOverallWidth = parseFloat(bodyStyle.width) + parseFloat(bodyStyle.paddingLeft) + parseFloat(bodyStyle.paddingRight);
				headCell.style.minWidth = `${bodyOverallWidth - parseFloat(headStyle.paddingLeft) - parseFloat(headStyle.paddingRight)}px`;
			}
		}
	}

	_updateStickyAncestor(node, popoverOpened) {
		if (!this.stickyHeaders) return;

		node = getComposedParent(node);
		while (node) {
			if (node === this) break;
			if (node.nodeType === Node.ELEMENT_NODE) {
				const style = window.getComputedStyle(node, null);
				if (style.getPropertyValue('position') === 'sticky') {

					let popoverCount = Number.parseInt(node.getAttribute('data-popover-count'));
					if (Number.isNaN(popoverCount)) popoverCount = 0;
					popoverOpened ? popoverCount++ : popoverCount--;

					if (popoverCount > 0) node.setAttribute('data-popover-count', popoverCount);
					else node.removeAttribute('data-popover-count');

					return;
				}
			}
			node = getComposedParent(node);
		}
	}

	_updateStickyTops() {
		const hasStickyControls = this._controls && !this._controls.noSticky;
		let rowTop = hasStickyControls ? this._controls.offsetHeight + 6 : 0; // +6 for the internal `margin-bottom`.
		this.style.setProperty('--d2l-table-sticky-top', `${rowTop}px`);

		if (!this._table || !this.stickyHeaders || this.stickyHeadersScrollWrapper) return;

		const stickyRows = Array.from(this._table.querySelectorAll(SELECTORS.headers));
		stickyRows.forEach(r => {
			const thTop = hasStickyControls ? `${rowTop}px` : `calc(${rowTop}px + var(--d2l-table-border-radius-sticky-offset, 0px))`;
			const ths = Array.from(r.querySelectorAll('th'));
			ths.forEach(th => th.style.top = thTop);

			const rowHeight = r.querySelector('th:not([rowspan])')?.offsetHeight || 0;
			rowTop += rowHeight;
		});
	}

}

customElements.define('d2l-table-wrapper', TableWrapper);