Source: ui/templates/referencePreview/referencePreview.js

/**
 * @module referencePreview
 */
import { isTrackingEnabled, LOGGING_SCHEMA } from '../../../instrumentation/referencePreviews';
import { renderPopup } from '../popup/popup';
import { createNodeFromTemplate, escapeHTML } from '../templateUtil';

const templateHTML = `
<div class="mwe-popups-container">
    <div class="mwe-popups-extract">
        <div class="mwe-popups-scroll">
            <strong class="mwe-popups-title">
                <span class="popups-icon"></span>
                <span class="mwe-popups-title-placeholder"></span>
            </strong>
            <div class="mw-parser-output"></div>
        </div>
        <div class="mwe-popups-fade"></div>
    </div>
	<footer>
		<div class="mwe-popups-settings"></div>
	</footer>
</div>`;

/**
 * @param {HTMLElement} node
 * @param {HTMLElement|string} htmlOrOtherNode
 */
const replaceWith = ( node, htmlOrOtherNode ) => {
	if ( typeof htmlOrOtherNode === 'string' ) {
		node.insertAdjacentHTML( 'afterend', htmlOrOtherNode );
	} else {
		node.parentNode.appendChild( htmlOrOtherNode );
	}
	node.remove();
};

/**
 * @param {ext.popups.ReferencePreviewModel} model
 * @return {JQuery}
 */
export function renderReferencePreview(
	model
) {
	const type = model.referenceType || 'generic';
	// The following messages are used here:
	// * popups-refpreview-book
	// * popups-refpreview-journal
	// * popups-refpreview-news
	// * popups-refpreview-note
	// * popups-refpreview-web
	let titleMsg = mw.message( `popups-refpreview-${type}` );
	if ( !titleMsg.exists() ) {
		titleMsg = mw.message( 'popups-refpreview-reference' );
	}

	const el = renderPopup( model.type, createNodeFromTemplate( templateHTML ) );
	replaceWith( el.querySelector( '.mwe-popups-title-placeholder' ), escapeHTML( titleMsg.text() ) );
	// The following classes are used here:
	// * popups-icon--reference-generic
	// * popups-icon--reference-book
	// * popups-icon--reference-journal
	// * popups-icon--reference-news
	// * popups-icon--reference-note
	// * popups-icon--reference-web
	el.querySelector( '.mwe-popups-title .popups-icon' )
		.classList.add( `popups-icon--reference-${type}` );
	el.querySelector( '.mw-parser-output' )
		.innerHTML = model.extract;

	// Make sure to not destroy existing targets, if any
	Array.prototype.forEach.call(
		el.querySelectorAll( '.mwe-popups-extract a[href][class~="external"]:not([target])' ),
		( a ) => {
			a.target = '_blank';
			// Don't let the external site access and possibly manipulate window.opener.location
			a.rel = `${a.rel ? `${a.rel} ` : ''}noopener`;
		}
	);

	// We assume elements that benefit from being collapsible are to large for the popup
	Array.prototype.forEach.call( el.querySelectorAll( '.mw-collapsible' ), ( node ) => {
		const otherNode = document.createElement( 'div' );
		otherNode.classList.add( 'mwe-collapsible-placeholder' );
		const icon = document.createElement( 'span' );
		icon.classList.add( 'popups-icon', 'popups-icon--infoFilled' );
		const label = document.createElement( 'span' );
		label.classList.add( 'mwe-collapsible-placeholder-label' );
		label.textContent = mw.msg( 'popups-refpreview-collapsible-placeholder' );
		otherNode.appendChild( icon );
		otherNode.appendChild( label );
		replaceWith( node, otherNode );
	} );

	// Undo remaining effects from the jquery.tablesorter.js plugin
	const undoHeaderSort = ( headerSort ) => {
		headerSort.classList.remove( 'headerSort' );
		headerSort.removeAttribute( 'tabindex' );
		headerSort.removeAttribute( 'title' );
	};
	Array.prototype.forEach.call( el.querySelectorAll( 'table.sortable' ), ( node ) => {
		node.classList.remove( 'sortable', 'jquery-tablesorter' );
		Array.prototype.forEach.call( node.querySelectorAll( '.headerSort' ), undoHeaderSort );
	} );

	// TODO: Remove when not in Beta any more
	if ( !mw.config.get( 'wgPopupsReferencePreviewsBetaFeature' ) ) {
		// TODO: Do not remove this but move it up into the templateHTML constant!
		const settingsButton = document.createElement( 'a' );
		settingsButton.classList.add( 'cdx-button', 'cdx-button--fake-button', 'cdx-button--fake-button--enabled', 'cdx-button--weight-quiet', 'cdx-button--icon-only', 'mwe-popups-settings-button' );
		const settingsIcon = document.createElement( 'span' );
		settingsIcon.classList.add( 'popups-icon', 'popups-icon--size-small', 'popups-icon--settings' );
		const settingsButtonLabel = document.createElement( 'span' );
		settingsButtonLabel.textContent = mw.msg( 'popups-settings-icon-gear-title' );
		settingsButton.append( settingsIcon );
		settingsButton.append( settingsButtonLabel );
		el.querySelector( '.mwe-popups-settings' ).appendChild( settingsButton );
	} else {
		// Change the styling when there is no content in the footer (to prevent empty space)
		el.querySelector( '.mwe-popups-container' ).classList.add( 'footer-empty' );
	}

	if ( isTrackingEnabled() ) {
		el.querySelector( '.mw-parser-output' ).addEventListener( 'click', ( ev ) => {
			if ( !ev.target.matches( 'a' ) ) {
				return;
			}
			mw.track( LOGGING_SCHEMA, {
				action: 'clickedReferencePreviewsContentLink'
			} );
		} );
	}

	el.querySelector( '.mwe-popups-scroll' ).addEventListener( 'scroll', function ( e ) {
		const element = e.target,
			// We are dealing with floating point numbers here when the page is zoomed!
			scrolledToBottom = element.scrollTop >= element.scrollHeight - element.clientHeight - 1;

		if ( isTrackingEnabled() ) {
			if ( !element.isOpenRecorded ) {
				mw.track( LOGGING_SCHEMA, {
					action: 'poppedOpen',
					scrollbarsPresent: element.scrollHeight > element.clientHeight
				} );
				element.isOpenRecorded = true;
			}

			if (
				element.scrollTop > 0 &&
				!element.isScrollRecorded
			) {
				mw.track( LOGGING_SCHEMA, {
					action: 'scrolled'
				} );
				element.isScrollRecorded = true;
			}
		}

		if ( !scrolledToBottom && element.isScrolling ) {
			return;
		}

		const extract = element.parentNode,
			hasHorizontalScroll = element.scrollWidth > element.clientWidth,
			scrollbarHeight = element.offsetHeight - element.clientHeight,
			hasVerticalScroll = element.scrollHeight > element.clientHeight,
			scrollbarWidth = element.offsetWidth - element.clientWidth;
		const fade = extract.querySelector( '.mwe-popups-fade' );
		fade.style.bottom = hasHorizontalScroll ? `${scrollbarHeight}px` : 0;
		fade.style.right = hasVerticalScroll ? `${scrollbarWidth}px` : 0;

		element.isScrolling = !scrolledToBottom;
		extract.classList.toggle( 'mwe-popups-fade-out', element.isScrolling );
	} );

	return el;
}