/**
* Provides a {@link jQuery} plugin that add suggestions to a text box.
*
* @module jquery.suggestions
*/
( function () {
/**
* Cancel any delayed maybeFetch() call and callback the context so
* they can cancel any async fetching if they use AJAX or something.
*
* @param {Object} context
*/
function cancel( context ) {
if ( context.data.timerID !== null ) {
clearTimeout( context.data.timerID );
}
if ( typeof context.config.cancel === 'function' ) {
context.config.cancel.call( context.data.$textbox );
}
}
/**
* Hide the element with suggestions and clean up some state.
*
* @param {Object} context
*/
function hide( context ) {
// Remove any highlights, including on "special" items
context.data.$container.find( '.suggestions-result-current' ).removeClass( 'suggestions-result-current' );
// Hide the container
context.data.$container.hide();
}
/**
* Restore the text the user originally typed in the textbox, before it
* was overwritten by highlight(). This restores the value the currently
* displayed suggestions are based on, rather than the value just before
* highlight() overwrote it; the former is arguably slightly more sensible.
*
* @param {Object} context
*/
function restore( context ) {
context.data.$textbox.val( context.data.prevText );
}
/**
* @param {Object} context
*/
function special( context ) {
// Allow custom rendering - but otherwise don't do any rendering
if ( typeof context.config.special.render === 'function' ) {
// Wait for the browser to update the value
setTimeout( () => {
// Render special
const $special = context.data.$container.find( '.suggestions-special' );
context.config.special.render.call( $special, context.data.$textbox.val(), context );
}, 1 );
}
}
/**
* Ask the user-specified callback for new suggestions. Any previous delayed
* call to this function still pending will be canceled. If the value in the
* textbox is empty or hasn't changed since the last time suggestions were fetched,
* this function does nothing.
*
* @param {Object} context
* @param {boolean} delayed Whether or not to delay this by the currently configured amount of time
*/
function update( context, delayed ) {
function maybeFetch() {
if ( typeof context.config.update.before === 'function' ) {
context.config.update.before.call( context.data.$textbox );
}
const val = context.data.$textbox.val(),
cache = context.data.cache;
let cacheHit = false;
// Only fetch if the value in the textbox changed and is not empty, or if the results were hidden
// if the textbox is empty then clear the result div, but leave other settings intouched
if ( val.length === 0 ) {
hide( context );
context.data.prevText = '';
} else if (
val !== context.data.prevText ||
// eslint-disable-next-line no-jquery/no-sizzle
!context.data.$container.is( ':visible' )
) {
context.data.prevText = val;
// Try cache first
if ( context.config.cache && val in cache ) {
if ( mw.now() - cache[ val ].timestamp < context.config.cacheMaxAge ) {
context.data.$textbox.suggestions( 'suggestions', cache[ val ].suggestions );
if ( typeof context.config.update.after === 'function' ) {
context.config.update.after.call( context.data.$textbox, cache[ val ].metadata );
}
cacheHit = true;
} else {
// Cache expired
delete cache[ val ];
}
}
if ( !cacheHit && typeof context.config.fetch === 'function' ) {
context.config.fetch.call(
context.data.$textbox,
val,
( suggestions, metadata ) => {
suggestions = suggestions.slice( 0, context.config.maxRows );
context.data.$textbox.suggestions( 'suggestions', suggestions );
if ( typeof context.config.update.after === 'function' ) {
context.config.update.after.call( context.data.$textbox, metadata );
}
if ( context.config.cache ) {
cache[ val ] = {
suggestions: suggestions,
metadata: metadata,
timestamp: mw.now()
};
}
},
context.config.maxRows
);
}
}
// Always update special rendering
special( context );
}
// Cancels any delayed maybeFetch call, and invokes context.config.cancel.
cancel( context );
if ( delayed ) {
// To avoid many started/aborted requests while typing, we're gonna take a short
// break before trying to fetch data.
context.data.timerID = setTimeout( maybeFetch, context.config.delay );
} else {
maybeFetch();
}
}
/**
* Highlight a result in the results table
*
* @param {Object} context
* @param {jQuery|string} $result `<tr>` to highlight, or 'prev' or 'next'
* @param {boolean} updateTextbox If true, put the suggestion in the textbox
*/
function highlight( context, $result, updateTextbox ) {
const $selected = context.data.$container.find( '.suggestions-result-current' );
if ( !$result.get || $selected.get( 0 ) !== $result.get( 0 ) ) {
if ( $result === 'prev' ) {
// eslint-disable-next-line no-jquery/no-class-state
if ( $selected.hasClass( 'suggestions-special' ) ) {
$result = context.data.$container.find( '.suggestions-result' ).last();
} else {
$result = $selected.prev();
// eslint-disable-next-line no-jquery/no-class-state
if ( !( $result.length && $result.hasClass( 'suggestions-result' ) ) ) {
// there is something in the DOM between selected element and the wrapper, bypass it
$result = $selected.parents( '.suggestions-results > *' ).prev().find( '.suggestions-result' ).eq( 0 );
}
if ( $selected.length === 0 ) {
// we are at the beginning, so lets jump to the last item
if ( context.data.$container.find( '.suggestions-special' ).html() !== '' ) {
$result = context.data.$container.find( '.suggestions-special' );
} else {
$result = context.data.$container.find( '.suggestions-results .suggestions-result' ).last();
}
}
}
} else if ( $result === 'next' ) {
if ( $selected.length === 0 ) {
// No item selected, go to the first one
$result = context.data.$container.find( '.suggestions-results .suggestions-result' ).first();
if ( $result.length === 0 && context.data.$container.find( '.suggestions-special' ).html() !== '' ) {
// No suggestion exists, go to the special one directly
$result = context.data.$container.find( '.suggestions-special' );
}
} else {
$result = $selected.next();
// eslint-disable-next-line no-jquery/no-class-state
if ( !( $result.length && $result.hasClass( 'suggestions-result' ) ) ) {
// there is something in the DOM between selected element and the wrapper, bypass it
$result = $selected.parents( '.suggestions-results > *' ).next().find( '.suggestions-result' ).eq( 0 );
}
// eslint-disable-next-line no-jquery/no-class-state
if ( $selected.hasClass( 'suggestions-special' ) ) {
$result = $( [] );
} else if (
$result.length === 0 &&
context.data.$container.find( '.suggestions-special' ).html() !== ''
) {
// We were at the last item, jump to the specials!
$result = context.data.$container.find( '.suggestions-special' );
}
}
}
$selected.removeClass( 'suggestions-result-current' );
$result.addClass( 'suggestions-result-current' );
}
if ( updateTextbox ) {
if ( $result.length === 0 || $result.is( '.suggestions-special' ) ) {
restore( context );
} else {
context.data.$textbox.val( $result.data( 'text' ) );
// .val() doesn't call any event handlers, so
// let the world know what happened
context.data.$textbox.trigger( 'change' );
}
context.data.$textbox.trigger( 'change' );
}
}
/**
* Sets the value of a property, and updates the widget accordingly
*
* @param {Object} context
* @param {string} property Name of property
* @param {any} value Value to set property with
*/
function configure( context, property, value ) {
// Validate creation using fallback values
switch ( property ) {
case 'fetch':
case 'cancel':
case 'special':
case 'result':
case 'update':
case '$region':
case 'expandFrom':
context.config[ property ] = value;
break;
case 'suggestions':
context.config[ property ] = value;
// Update suggestions
if ( context.data !== undefined ) {
if ( context.data.$textbox.val().length === 0 ) {
// Hide the div when no suggestion exist
hide( context );
} else {
// Rebuild the suggestions list
context.data.$container.show();
// Update the size and position of the list
const regionIsFixed = ( function () {
let $el = context.config.$region;
do {
if ( $el.css( 'position' ) === 'fixed' ) {
return true;
}
$el = $( $el[ 0 ].offsetParent );
} while ( $el.length );
return false;
}() );
const regionPosition = regionIsFixed ?
context.config.$region[ 0 ].getBoundingClientRect() :
context.config.$region.offset();
const newCSS = {
position: regionIsFixed ? 'fixed' : 'absolute',
top: regionPosition.top + context.config.$region.outerHeight(),
bottom: 'auto',
width: context.config.$region.outerWidth(),
height: 'auto'
};
// Process expandFrom, after this it is set to left or right.
context.config.expandFrom = ( function ( expandFrom ) {
const isRTL = $( document.documentElement ).css( 'direction' ) === 'rtl',
$region = context.config.$region;
// Backwards compatible
if ( context.config.positionFromLeft ) {
expandFrom = 'left';
// Catch invalid values, default to 'auto'
} else if ( [ 'left', 'right', 'start', 'end', 'auto' ].indexOf( expandFrom ) === -1 ) {
expandFrom = 'auto';
}
if ( expandFrom === 'auto' ) {
if ( $region.data( 'searchsuggest-expand-dir' ) ) {
// If the markup explicitly contains a direction, use it.
expandFrom = $region.data( 'searchsuggest-expand-dir' );
} else {
const regionWidth = $region.outerWidth();
const docWidth = $( document ).width();
if ( regionWidth > ( 0.85 * docWidth ) ) {
// If the input size takes up more than 85% of the document horizontally
// expand the suggestions to the writing direction's native end.
expandFrom = 'start';
} else {
// Calculate the center points of the input and document
const regionCenter = regionPosition.left + regionWidth / 2;
const docCenter = docWidth / 2;
if ( Math.abs( regionCenter - docCenter ) < ( 0.10 * docCenter ) ) {
// If the input's center is within 10% of the document center
// use the writing direction's native end.
expandFrom = 'start';
} else {
// Otherwise expand the input from the closest side of the page,
// towards the side of the page with the most free open space
expandFrom = regionCenter > docCenter ? 'right' : 'left';
}
}
}
}
if ( expandFrom === 'start' ) {
expandFrom = isRTL ? 'right' : 'left';
} else if ( expandFrom === 'end' ) {
expandFrom = isRTL ? 'left' : 'right';
}
return expandFrom;
}( context.config.expandFrom ) );
if ( context.config.expandFrom === 'left' ) {
// Expand from left
newCSS.left = regionPosition.left;
newCSS.right = 'auto';
} else {
// Expand from right
newCSS.left = 'auto';
newCSS.right = document.documentElement.clientWidth -
( regionPosition.left + context.config.$region.outerWidth() );
}
context.data.$container.css( newCSS );
const $results = context.data.$container.children( '.suggestions-results' );
$results.empty();
let expWidth = -1;
for ( let i = 0; i < context.config.suggestions.length; i++ ) {
const text = context.config.suggestions[ i ];
const $result = $( '<div>' )
.addClass( 'suggestions-result' )
.attr( 'rel', i )
.data( 'text', context.config.suggestions[ i ] )
.on( 'mousemove', function () {
context.data.selectedWithMouse = true;
highlight(
context,
$( this ).closest( '.suggestions-results .suggestions-result' ),
false
);
} )
.appendTo( $results );
// Allow custom rendering
if ( typeof context.config.result.render === 'function' ) {
context.config.result.render.call( $result, context.config.suggestions[ i ], context );
} else {
$result.text( text );
}
if ( context.config.highlightInput ) {
$result.highlightText( context.data.prevText, { method: 'prefixPlusComboHighlight' } );
}
// Widen results box if needed (new width is only calculated here, applied later).
// The monstrosity below accomplishes two things:
// * Wraps the text contents in a DOM element, so that we can know its width. There is
// no way to directly access the width of a text node, and we can't use the parent
// node width as it has text-overflow: ellipsis; and overflow: hidden; applied to
// it, which trims it to a smaller width.
// * Temporarily applies position: absolute; to the wrapper to pull it out of normal
// document flow. Otherwise the CSS text-overflow: ellipsis; and overflow: hidden;
// rules would cause some browsers (at least all versions of IE from 6 to 11) to
// still report the "trimmed" width. This should not be done in regular CSS
// stylesheets as we don't want this rule to apply to other <span> elements, like
// the ones generated by jquery.highlightText.
const $spanForWidth = $result.wrapInner( '<span>' ).children();
const childrenWidth = $spanForWidth.css( 'position', 'absolute' ).outerWidth();
$spanForWidth.contents().unwrap();
if ( childrenWidth > $result.width() && childrenWidth > expWidth ) {
// factor in any padding, margin, or border space on the parent
expWidth = childrenWidth + ( context.data.$container.width() - $result.width() );
}
}
// Apply new width for results box, if any
if ( expWidth > context.data.$container.width() ) {
const maxWidth = context.config.maxExpandFactor * context.data.$textbox.width();
context.data.$container.width( Math.min( expWidth, maxWidth ) );
}
}
}
break;
case 'maxRows':
context.config[ property ] = Math.max( 1, Math.min( 100, value ) );
break;
case 'delay':
context.config[ property ] = Math.max( 0, Math.min( 1200, value ) );
break;
case 'cacheMaxAge':
context.config[ property ] = Math.max( 1, value );
break;
case 'maxExpandFactor':
context.config[ property ] = Math.max( 1, value );
break;
case 'cache':
case 'submitOnClick':
case 'positionFromLeft':
case 'highlightInput':
context.config[ property ] = !!value;
break;
}
}
/**
* Respond to keypress event
*
* @param {jQuery.Event} e
* @param {Object} context
* @param {number} key Code of key pressed
*/
function keypress( e, context, key ) {
// eslint-disable-next-line no-jquery/no-sizzle
const wasVisible = context.data.$container.is( ':visible' );
let preventDefault = false;
switch ( key ) {
// Arrow down
case 40:
if ( wasVisible ) {
highlight( context, 'next', true );
context.data.selectedWithMouse = false;
} else {
update( context, false );
}
preventDefault = true;
break;
// Arrow up
case 38:
if ( wasVisible ) {
highlight( context, 'prev', true );
context.data.selectedWithMouse = false;
}
preventDefault = wasVisible;
break;
// Escape
case 27:
hide( context );
restore( context );
cancel( context );
context.data.$textbox.trigger( 'change' );
preventDefault = wasVisible;
break;
// Enter
case 13: {
preventDefault = wasVisible;
const $selected = context.data.$container.find( '.suggestions-result-current' );
hide( context );
if ( $selected.length === 0 || context.data.selectedWithMouse ) {
// If nothing is selected or if something was selected with the mouse
// cancel any current requests and allow the form to be submitted
// (simply don't prevent default behavior).
cancel( context );
preventDefault = false;
} else if ( $selected.is( '.suggestions-special' ) ) {
if ( typeof context.config.special.select === 'function' ) {
// Allow the callback to decide whether to prevent default or not
if ( context.config.special.select.call( $selected, context.data.$textbox, 'keyboard' ) === true ) {
preventDefault = false;
}
}
} else {
if ( typeof context.config.result.select === 'function' ) {
// Allow the callback to decide whether to prevent default or not
if ( context.config.result.select.call( $selected, context.data.$textbox, 'keyboard' ) === true ) {
preventDefault = false;
}
}
}
break;
}
default:
update( context, true );
break;
}
if ( preventDefault ) {
e.preventDefault();
e.stopPropagation();
}
}
/**
* Add suggestions to a text box.
*
* Set options:
*
* ```
* $( '#textbox' ).suggestions( { option1: value1, option2: value2 } );
* $( '#textbox' ).suggestions( option, value );
* ```
*
* To use this {@link jQuery} plugin, load the `jquery.suggestions` module with {@link mw.loader}.
*
* @example
* // Initialize:
* mw.loader.using( 'jquery.suggestions' ).then(()=> {
* $( '#textbox' ).suggestions();
* });
* @memberof module:jquery.suggestions
* @return {jQuery}
*
* @param {Object} options
*
* @param {Function} [options.fetch] Callback that should fetch suggestions and set the suggestions
* property. Called in context of the text box.
* @param {string} options.fetch.query
* @param {Function} options.fetch.response Callback to receive the suggestions with
* @param {Array} options.fetch.response.suggestions
* @param {number} options.fetch.maxRows
*
* @param {Function} [options.cancel] Callback function to call when any pending asynchronous
* suggestions fetches. Called in context of the text box.
*
* @param {Object} [options.special] Set of callbacks for rendering and selecting.
*
* @param {Function} options.special.render Called in context of the suggestions-special element.
* @param {string} options.special.render.query
* @param {Object} options.special.render.context
*
* @param {Function} options.special.select Called in context of the suggestions-result-current element.
* @param {jQuery} options.special.select.$textbox
*
* @param {Object} [options.result] Set of callbacks for rendering and selecting
*
* @param {Function} options.result.render Called in context of the suggestions-result element.
* @param {string} options.result.render.suggestion
* @param {Object} options.result.render.context
*
* @param {Function} options.result.select Called in context of the suggestions-result-current element.
* @param {jQuery} options.result.select.$textbox
*
* @param {Object} [options.update] Set of callbacks for listening to a change in the text input.
*
* @param {Function} options.update.before Called right after the user changes the textbox text.
* @param {Function} options.update.after Called after results are updated either from the cache or
* the API as a result of the user input.
*
* @param {jQuery} [options.$region=this] The element to place the suggestions below and match width of.
*
* @param {string[]} [options.suggestions] Array of suggestions to display.
*
* @param {number} [options.maxRows=10] Maximum number of suggestions to display at one time.
* Must be between 1 and 100.
*
* @param {number} [options.delay=120] Number of milliseconds to wait for the user to stop typing.
* Must be between 0 and 1200.
*
* @param {boolean} [options.cache=false] Whether to cache results from a fetch.
*
* @param {number} [options.cacheMaxAge=60000] Number of milliseconds to cache results from a fetch.
* Must be higher than 1. Defaults to 1 minute.
*
* @param {boolean} [options.submitOnClick=false] Whether to submit the form containing the textbox
* when a suggestion is clicked.
*
* @param {number} [options.maxExpandFactor=3] Maximum suggestions box width relative to the textbox
* width. If set to e.g. 2, the suggestions box will never be grown beyond 2 times the width of
* the textbox. Must be higher than 1.
*
* @param {string} [options.expandFrom=auto] Which direction to offset the suggestion box from.
* Values 'start' and 'end' translate to left and right respectively depending on the directionality
* of the current document, according to `$( document.documentElement ).css( 'direction' )`.
* Valid values: "left", "right", "start", "end", and "auto".
*
* @param {boolean} [options.positionFromLeft] Sets `expandFrom=left`, for backwards
* compatibility.
*
* @param {boolean} [options.highlightInput=false] Whether to highlight matched portions of the
* input or not.
*/
$.fn.suggestions = function () {
// Multi-context fields
const args = arguments;
$( this ).each( function () {
/* Construction and Loading */
let context = $( this ).data( 'suggestions-context' );
if ( context === undefined || context === null ) {
context = {
config: {
fetch: function () {},
cancel: function () {},
special: {},
result: {},
update: {},
$region: $( this ),
suggestions: [],
maxRows: 10,
delay: 120,
cache: false,
cacheMaxAge: 60000,
submitOnClick: false,
maxExpandFactor: 3,
expandFrom: 'auto',
highlightInput: false
}
};
}
/* API */
// Handle various calling styles
if ( args.length > 0 ) {
if ( typeof args[ 0 ] === 'object' ) {
// Apply set of properties
for ( const key in args[ 0 ] ) {
configure( context, key, args[ 0 ][ key ] );
}
} else if ( typeof args[ 0 ] === 'string' ) {
if ( args.length > 1 ) {
// Set property values
configure( context, args[ 0 ], args[ 1 ] );
}
}
}
/* Initialization */
if ( context.data === undefined ) {
context.data = {
// ID of running timer
timerID: null,
// Text in textbox when suggestions were last fetched
prevText: null,
// Cache of fetched suggestions
cache: Object.create( null ),
// Number of results visible without scrolling
visibleResults: 0,
// Suggestion the last mousedown event occurred on
$mouseDownOn: $( [] ),
$textbox: $( this ),
selectedWithMouse: false
};
context.data.$container = $( '<div>' )
.css( 'display', 'none' )
.addClass( 'suggestions' )
.append(
$( '<div>' ).addClass( 'suggestions-results' )
// Can't use click() because the container div is hidden when the
// textbox loses focus. Instead, listen for a mousedown followed
// by a mouseup on the same div.
.on( 'mousedown', ( e ) => {
context.data.$mouseDownOn = $( e.target ).closest( '.suggestions-results .suggestions-result' );
} )
.on( 'mouseup', ( e ) => {
const $result = $( e.target ).closest( '.suggestions-results .suggestions-result' ),
$other = context.data.$mouseDownOn;
context.data.$mouseDownOn = $( [] );
if ( $result.get( 0 ) !== $other.get( 0 ) ) {
return;
}
highlight( context, $result, true );
if ( typeof context.config.result.select === 'function' ) {
context.config.result.select.call( $result, context.data.$textbox, 'mouse' );
}
// Don't interfere with special clicks (e.g. to open in new tab)
if ( !( e.which !== 1 || e.altKey || e.ctrlKey || e.shiftKey || e.metaKey ) ) {
// This will hide the link we're just clicking on, which causes problems
// when done synchronously in at least Firefox 3.6 (T64858).
setTimeout( () => {
hide( context );
} );
}
// Always bring focus to the textbox, as that's probably where the user expects it
// if they were just typing.
context.data.$textbox.trigger( 'focus' );
} )
)
.append(
$( '<div>' ).addClass( 'suggestions-special' )
// Can't use click() because the container div is hidden when the
// textbox loses focus. Instead, listen for a mousedown followed
// by a mouseup on the same div.
.on( 'mousedown', ( e ) => {
context.data.$mouseDownOn = $( e.target ).closest( '.suggestions-special' );
} )
.on( 'mouseup', ( e ) => {
const $special = $( e.target ).closest( '.suggestions-special' ),
$other = context.data.$mouseDownOn;
context.data.$mouseDownOn = $( [] );
if ( $special.get( 0 ) !== $other.get( 0 ) ) {
return;
}
if ( typeof context.config.special.select === 'function' ) {
context.config.special.select.call( $special, context.data.$textbox, 'mouse' );
}
// Don't interfere with special clicks (e.g. to open in new tab)
if ( !( e.which !== 1 || e.altKey || e.ctrlKey || e.shiftKey || e.metaKey ) ) {
// This will hide the link we're just clicking on, which causes problems
// when done synchronously in at least Firefox 3.6 (T64858).
setTimeout( () => {
hide( context );
} );
}
// Always bring focus to the textbox, as that's probably where the user expects it
// if they were just typing.
context.data.$textbox.trigger( 'focus' );
} )
.on( 'mousemove', ( e ) => {
context.data.selectedWithMouse = true;
highlight(
context, $( e.target ).closest( '.suggestions-special' ), false
);
} )
)
.appendTo( document.body );
$( this )
// Stop browser autocomplete from interfering
.attr( 'autocomplete', 'off' )
.on( 'keydown', ( e ) => {
// Store key pressed to handle later
context.data.keypressed = e.which;
context.data.keypressedCount = 0;
} )
.on( 'keypress', ( e ) => {
context.data.keypressedCount++;
keypress( e, context, context.data.keypressed );
} )
.on( 'keyup', ( e ) => {
// The keypress event is fired when a key is pressed down and that key normally
// produces a character value. We also want to handle some keys that don't
// produce a character value so we also attach to the keydown/keyup events.
// List of codes sourced from
// https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode
const allowed = [
40, // up arrow
38, // down arrow
27, // escape
13, // enter
46, // delete
8 // backspace
];
if ( context.data.keypressedCount === 0 &&
e.which === context.data.keypressed &&
allowed.indexOf( e.which ) !== -1
) {
keypress( e, context, context.data.keypressed );
}
} )
.on( 'blur', () => {
// When losing focus because of a mousedown
// on a suggestion, don't hide the suggestions
if ( context.data.$mouseDownOn.length > 0 ) {
return;
}
hide( context );
cancel( context );
} );
// Load suggestions if the value is changed because there are already
// typed characters before the JavaScript is loaded.
if ( $( this ).is( ':focus' ) && this.value !== this.defaultValue ) {
update( context, false );
}
}
// Store the context for next time
$( this ).data( 'suggestions-context', context );
} );
return this;
};
/**
* @class jQuery
* @mixes jQuery.plugin.suggestions
*/
}() );