// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Emoji picker.
*
* @module core/emoji/picker
* @copyright 2019 Ryan Wyllie <ryan@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
import LocalStorage from 'core/localstorage';
import * as EmojiData from 'core/emoji/data';
import {throttle, debounce} from 'core/utils';
import {get_string as getString} from 'core/str';
import {render as renderTemplate} from 'core/templates';
const VISIBLE_ROW_COUNT = 10;
const ROW_RENDER_BUFFER_COUNT = 5;
const RECENT_EMOJIS_STORAGE_KEY = 'moodle-recent-emojis';
const ROW_HEIGHT_RAW = 40;
const EMOJIS_PER_ROW = 7;
const MAX_RECENT_COUNT = EMOJIS_PER_ROW * 3;
const ROW_TYPE = {
EMOJI: 0,
HEADER: 1
};
const SELECTORS = {
CATEGORY_SELECTOR: '[data-action="show-category"]',
EMOJIS_CONTAINER: '[data-region="emojis-container"]',
EMOJI_PREVIEW: '[data-region="emoji-preview"]',
EMOJI_SHORT_NAME: '[data-region="emoji-short-name"]',
ROW_CONTAINER: '[data-region="row-container"]',
SEARCH_INPUT: '[data-region="search-input"]',
SEARCH_RESULTS_CONTAINER: '[data-region="search-results-container"]'
};
/**
* Create the row data for a category.
*
* @method
* @param {String} categoryName The category name
* @param {String} categoryDisplayName The category display name
* @param {Array} emojis The emoji data
* @param {Number} totalRowCount The total number of rows generated so far
* @return {Array}
*/
const createRowDataForCategory = (categoryName, categoryDisplayName, emojis, totalRowCount) => {
const rowData = [];
rowData.push({
index: totalRowCount + rowData.length,
type: ROW_TYPE.HEADER,
data: {
name: categoryName,
displayName: categoryDisplayName
}
});
for (let i = 0; i < emojis.length; i += EMOJIS_PER_ROW) {
const rowEmojis = emojis.slice(i, i + EMOJIS_PER_ROW);
rowData.push({
index: totalRowCount + rowData.length,
type: ROW_TYPE.EMOJI,
data: rowEmojis
});
}
return rowData;
};
/**
* Add each row's index to it's value in the row data.
*
* @method
* @param {Array} rowData List of emoji row data
* @return {Array}
*/
const addIndexesToRowData = (rowData) => {
return rowData.map((data, index) => {
return {...data, index};
});
};
/**
* Calculate the scroll position for the beginning of each category from
* the row data.
*
* @method
* @param {Array} rowData List of emoji row data
* @return {Object}
*/
const getCategoryScrollPositionsFromRowData = (rowData) => {
return rowData.reduce((carry, row, index) => {
if (row.type === ROW_TYPE.HEADER) {
carry[row.data.name] = index * ROW_HEIGHT_RAW;
}
return carry;
}, {});
};
/**
* Create a header row element for the category name.
*
* @method
* @param {Number} rowIndex Index of the row in the row data
* @param {String} name The category display name
* @return {Element}
*/
const createHeaderRow = async(rowIndex, name) => {
const context = {
index: rowIndex,
text: name
};
const html = await renderTemplate('core/emoji/header_row', context);
const temp = document.createElement('div');
temp.innerHTML = html;
return temp.firstChild;
};
/**
* Create an emoji row element.
*
* @method
* @param {Number} rowIndex Index of the row in the row data
* @param {Array} emojis The list of emoji data for the row
* @return {Element}
*/
const createEmojiRow = async(rowIndex, emojis) => {
const context = {
index: rowIndex,
emojis: emojis.map(emojiData => {
const charCodes = emojiData.unified.split('-').map(code => `0x${code}`);
const emojiText = String.fromCodePoint.apply(null, charCodes);
return {
shortnames: `:${emojiData.shortnames.join(': :')}:`,
unified: emojiData.unified,
text: emojiText,
spacer: false
};
}),
spacers: Array(EMOJIS_PER_ROW - emojis.length).fill(true)
};
const html = await renderTemplate('core/emoji/emoji_row', context);
const temp = document.createElement('div');
temp.innerHTML = html;
return temp.firstChild;
};
/**
* Check if the element is an emoji element.
*
* @method
* @param {Element} element Element to check
* @return {Bool}
*/
const isEmojiElement = element => element.getAttribute('data-short-names') !== null;
/**
* Search from an element and up through it's ancestors to fine the category
* selector element and return it.
*
* @method
* @param {Element} element Element to begin searching from
* @return {Element|null}
*/
const findCategorySelectorFromElement = element => {
if (!element) {
return null;
}
if (element.getAttribute('data-action') === 'show-category') {
return element;
} else {
return findCategorySelectorFromElement(element.parentElement);
}
};
const getCategorySelectorByCategoryName = (root, name) => {
return root.querySelector(`[data-category="${name}"]`);
};
/**
* Sets the given category selector element as active.
*
* @method
* @param {Element} root The root picker element
* @param {Element} element The category selector element to make active
*/
const setCategorySelectorActive = (root, element) => {
const allCategorySelectors = root.querySelectorAll(SELECTORS.CATEGORY_SELECTOR);
for (let i = 0; i < allCategorySelectors.length; i++) {
const selector = allCategorySelectors[i];
selector.classList.remove('selected');
}
element.classList.add('selected');
};
/**
* Get the category selector element and the scroll positions for the previous and
* next categories for the given scroll position.
*
* @method
* @param {Element} root The picker root element
* @param {Number} position The position to get the category for
* @param {Object} categoryScrollPositions Set of scroll positions for all categories
* @return {Array}
*/
const getCategoryByScrollPosition = (root, position, categoryScrollPositions) => {
let positions = [];
if (position < 0) {
position = 0;
}
// Get all of the category positions.
for (const categoryName in categoryScrollPositions) {
const categoryPosition = categoryScrollPositions[categoryName];
positions.push([categoryPosition, categoryName]);
}
// Sort the positions in ascending order.
positions.sort(([a], [b]) => {
if (a < b) {
return -1;
} else if (a > b) {
return 1;
} else {
return 0;
}
});
// Get the current category name as well as the previous and next category
// positions from the sorted list of positions.
const {categoryName, previousPosition, nextPosition} = positions.reduce(
(carry, candidate) => {
const [categoryPosition, categoryName] = candidate;
if (categoryPosition <= position) {
carry.categoryName = categoryName;
carry.previousPosition = carry.currentPosition;
carry.currentPosition = position;
} else if (carry.nextPosition === null) {
carry.nextPosition = categoryPosition;
}
return carry;
},
{
categoryName: null,
currentPosition: null,
previousPosition: null,
nextPosition: null
}
);
return [getCategorySelectorByCategoryName(root, categoryName), previousPosition, nextPosition];
};
/**
* Get the list of recent emojis data from local storage.
*
* @method
* @return {Array}
*/
const getRecentEmojis = () => {
const storedData = LocalStorage.get(RECENT_EMOJIS_STORAGE_KEY);
return storedData ? JSON.parse(storedData) : [];
};
/**
* Save the list of recent emojis in local storage.
*
* @method
* @param {Array} recentEmojis List of emoji data to save
*/
const saveRecentEmoji = (recentEmojis) => {
LocalStorage.set(RECENT_EMOJIS_STORAGE_KEY, JSON.stringify(recentEmojis));
};
/**
* Add an emoji data to the set of recent emojis. This function will update the row
* data to ensure that the recent emoji rows are correct and all of the rows are
* re-indexed.
*
* The new set of recent emojis are saved in local storage and the full set of updated
* row data and new emoji row count are returned.
*
* @method
* @param {Array} rowData The emoji rows data
* @param {Number} recentEmojiRowCount Count of the recent emoji rows
* @param {Object} newEmoji The emoji data for the emoji to add to the recent emoji list
* @return {Array}
*/
const addRecentEmoji = (rowData, recentEmojiRowCount, newEmoji) => {
// The first set of rows is always the recent emojis.
const categoryName = rowData[0].data.name;
const categoryDisplayName = rowData[0].data.displayName;
const recentEmojis = getRecentEmojis();
// Add the new emoji to the start of the list of recent emojis.
let newRecentEmojis = [newEmoji, ...recentEmojis.filter(emoji => emoji.unified != newEmoji.unified)];
// Limit the number of recent emojis.
newRecentEmojis = newRecentEmojis.slice(0, MAX_RECENT_COUNT);
const newRecentEmojiRowData = createRowDataForCategory(categoryName, categoryDisplayName, newRecentEmojis);
// Save the new list in local storage.
saveRecentEmoji(newRecentEmojis);
return [
// Return the new rowData and re-index it to make sure it's all correct.
addIndexesToRowData(newRecentEmojiRowData.concat(rowData.slice(recentEmojiRowCount))),
newRecentEmojiRowData.length
];
};
/**
* Calculate which rows should be visible based on the given scroll position. Adds a
* buffer to amount to either side of the total number of requested rows so that
* scrolling the emoji rows container is smooth.
*
* @method
* @param {Number} scrollPosition Scroll position within the emoji container
* @param {Number} visibleRowCount How many rows should be visible
* @param {Array} rowData The emoji rows data
* @return {Array}
*/
const getRowsToRender = (scrollPosition, visibleRowCount, rowData) => {
const minVisibleRow = scrollPosition > ROW_HEIGHT_RAW ? Math.floor(scrollPosition / ROW_HEIGHT_RAW) : 0;
const start = minVisibleRow >= ROW_RENDER_BUFFER_COUNT ? minVisibleRow - ROW_RENDER_BUFFER_COUNT : minVisibleRow;
const end = minVisibleRow + visibleRowCount + ROW_RENDER_BUFFER_COUNT;
const rows = rowData.slice(start, end);
return rows;
};
/**
* Create a row element from the row data.
*
* @method
* @param {Object} rowData The emoji row data
* @return {Element}
*/
const createRowElement = async(rowData) => {
let row = null;
if (rowData.type === ROW_TYPE.HEADER) {
row = await createHeaderRow(rowData.index, rowData.data.displayName);
} else {
row = await createEmojiRow(rowData.index, rowData.data);
}
row.style.position = 'absolute';
row.style.left = 0;
row.style.right = 0;
row.style.top = `${rowData.index * ROW_HEIGHT_RAW}px`;
return row;
};
/**
* Check if the given rows match.
*
* @method
* @param {Object} a The first row
* @param {Object} b The second row
* @return {Bool}
*/
const doRowsMatch = (a, b) => {
if (a.index !== b.index) {
return false;
}
if (a.type !== b.type) {
return false;
}
if (typeof a.data != typeof b.data) {
return false;
}
if (a.type === ROW_TYPE.HEADER) {
return a.data.name === b.data.name;
} else {
if (a.data.length !== b.data.length) {
return false;
}
for (let i = 0; i < a.data.length; i++) {
if (a.data[i].unified != b.data[i].unified) {
return false;
}
}
}
return true;
};
/**
* Update the visible rows. Deletes any row elements that should no longer
* be visible and creates the newly visible row elements. Any rows that haven't
* changed visibility will be left untouched.
*
* @method
* @param {Element} rowContainer The container element for the emoji rows
* @param {Array} currentRows List of row data that matches the currently visible rows
* @param {Array} nextRows List of row data containing the new list of rows to be made visible
*/
const renderRows = async(rowContainer, currentRows, nextRows) => {
// We need to add any rows that are in nextRows but not in currentRows.
const toAdd = nextRows.filter(nextRow => !currentRows.some(currentRow => doRowsMatch(currentRow, nextRow)));
// Remember which rows will still be visible so that we can insert our element in the correct place in the DOM.
let toKeep = currentRows.filter(currentRow => nextRows.some(nextRow => doRowsMatch(currentRow, nextRow)));
// We need to remove any rows that are in currentRows but not in nextRows.
const toRemove = currentRows.filter(currentRow => !nextRows.some(nextRow => doRowsMatch(currentRow, nextRow)));
const toRemoveElements = toRemove.map(rowData => rowContainer.querySelectorAll(`[data-row="${rowData.index}"]`));
// Render all of the templates first.
const rows = await Promise.all(toAdd.map(rowData => createRowElement(rowData)));
rows.forEach((row, index) => {
const rowData = toAdd[index];
let nextRowIndex = null;
for (let i = 0; i < toKeep.length; i++) {
const candidate = toKeep[i];
if (candidate.index > rowData.index) {
nextRowIndex = i;
break;
}
}
// Make sure the elements get added to the DOM in the correct order (ascending by row data index)
// so that they appear naturally in the tab order.
if (nextRowIndex !== null) {
const nextRowData = toKeep[nextRowIndex];
const nextRowNode = rowContainer.querySelector(`[data-row="${nextRowData.index}"]`);
rowContainer.insertBefore(row, nextRowNode);
toKeep.splice(nextRowIndex, 0, toKeep);
} else {
toKeep.push(rowData);
rowContainer.appendChild(row);
}
});
toRemoveElements.forEach(rows => {
for (let i = 0; i < rows.length; i++) {
const row = rows[i];
rowContainer.removeChild(row);
}
});
};
/**
* Build a function to render the visible emoji rows for a given scroll
* position.
*
* @method
* @param {Element} rowContainer The container element for the emoji rows
* @return {Function}
*/
const generateRenderRowsAtPositionFunction = (rowContainer) => {
let currentRows = [];
let nextRows = [];
let rowCount = 0;
let isRendering = false;
const renderNextRows = async() => {
if (!nextRows.length) {
return;
}
if (isRendering) {
return;
}
isRendering = true;
const nextRowsToRender = nextRows.slice();
nextRows = [];
await renderRows(rowContainer, currentRows, nextRowsToRender);
currentRows = nextRowsToRender;
isRendering = false;
renderNextRows();
};
return (scrollPosition, rowData, rowLimit = VISIBLE_ROW_COUNT) => {
nextRows = getRowsToRender(scrollPosition, rowLimit, rowData);
renderNextRows();
if (rowCount !== rowData.length) {
// Adjust the height of the container to match the number of rows.
rowContainer.style.height = `${rowData.length * ROW_HEIGHT_RAW}px`;
}
rowCount = rowData.length;
};
};
/**
* Show the search results container and hide the emoji container.
*
* @method
* @param {Element} emojiContainer The emojis container
* @param {Element} searchResultsContainer The search results container
*/
const showSearchResults = (emojiContainer, searchResultsContainer) => {
searchResultsContainer.classList.remove('hidden');
emojiContainer.classList.add('hidden');
};
/**
* Hide the search result container and show the emojis container.
*
* @method
* @param {Element} emojiContainer The emojis container
* @param {Element} searchResultsContainer The search results container
* @param {Element} searchInput The search input
*/
const clearSearch = (emojiContainer, searchResultsContainer, searchInput) => {
searchResultsContainer.classList.add('hidden');
emojiContainer.classList.remove('hidden');
searchInput.value = '';
};
/**
* Build function to handle mouse hovering an emoji. Shows the preview.
*
* @method
* @param {Element} emojiPreview The emoji preview element
* @param {Element} emojiShortName The emoji short name element
* @return {Function}
*/
const getHandleMouseEnter = (emojiPreview, emojiShortName) => {
return (e) => {
const target = e.target;
if (isEmojiElement(target)) {
emojiShortName.textContent = target.getAttribute('data-short-names');
emojiPreview.textContent = target.textContent;
}
};
};
/**
* Build function to handle mouse leaving an emoji. Removes the preview.
*
* @method
* @param {Element} emojiPreview The emoji preview element
* @param {Element} emojiShortName The emoji short name element
* @return {Function}
*/
const getHandleMouseLeave = (emojiPreview, emojiShortName) => {
return (e) => {
const target = e.target;
if (isEmojiElement(target)) {
emojiShortName.textContent = '';
emojiPreview.textContent = '';
}
};
};
/**
* Build the function to handle a user clicking something in the picker.
*
* The function currently handles clicking on the category selector or selecting
* a specific emoji.
*
* @method
* @param {Number} recentEmojiRowCount Number of rows of recent emojis
* @param {Element} emojiContainer Container element for the visible of emojis
* @param {Element} searchResultsContainer Contaienr element for the search results
* @param {Element} searchInput Search input element
* @param {Function} selectCallback Callback function to execute when a user selects an emoji
* @param {Function} renderAtPosition Render function to display current visible emojis
* @return {Function}
*/
const getHandleClick = (
recentEmojiRowCount,
emojiContainer,
searchResultsContainer,
searchInput,
selectCallback,
renderAtPosition
) => {
return (e, rowData, categoryScrollPositions) => {
const target = e.target;
let newRowData = rowData;
let newCategoryScrollPositions = categoryScrollPositions;
// Hide the search results if they are visible.
clearSearch(emojiContainer, searchResultsContainer, searchInput);
if (isEmojiElement(target)) {
// Emoji selected.
const unified = target.getAttribute('data-unified');
const shortnames = target.getAttribute('data-short-names').replace(/:/g, '').split(' ');
// Build the emoji data from the selected element.
const emojiData = {unified, shortnames};
const currentScrollTop = emojiContainer.scrollTop;
const isRecentEmojiRowVisible = emojiContainer.querySelector(`[data-row="${recentEmojiRowCount - 1}"]`) !== null;
// Save the selected emoji in the recent emojis list.
[newRowData, recentEmojiRowCount] = addRecentEmoji(rowData, recentEmojiRowCount, emojiData);
// Re-index the category scroll positions because the additional recent emoji may have
// changed their positions.
newCategoryScrollPositions = getCategoryScrollPositionsFromRowData(newRowData);
if (isRecentEmojiRowVisible) {
// If the list of recent emojis is currently visible then we need to re-render the emojis
// to update the display and show the newly selected recent emoji.
renderAtPosition(currentScrollTop, newRowData);
}
// Call the client's callback function with the selected emoji.
selectCallback(target.textContent);
// Return the newly calculated row data and scroll positions.
return [newRowData, newCategoryScrollPositions];
}
const categorySelector = findCategorySelectorFromElement(target);
if (categorySelector) {
// Category selector.
const selectedCategory = categorySelector.getAttribute('data-category');
const position = categoryScrollPositions[selectedCategory];
// Scroll the container to the selected category. This will trigger the
// on scroll handler to re-render the visibile emojis.
emojiContainer.scrollTop = position;
}
return [newRowData, newCategoryScrollPositions];
};
};
/**
* Build the function that handles scrolling of the emoji container to display the
* correct emojis.
*
* We render the emoji rows as they are needed rather than all up front so that we
* can avoid adding tends of thousands of elements to the DOM unnecessarily which
* would bog down performance.
*
* @method
* @param {Element} root The picker root element
* @param {Number} currentVisibleRowScrollPosition The current scroll position of the container
* @param {Element} emojiContainer The emojis container element
* @param {Object} initialCategoryScrollPositions Scroll positions for each category
* @param {Function} renderAtPosition Function to render the appropriate emojis for a scroll position
* @return {Function}
*/
const getHandleScroll = (
root,
currentVisibleRowScrollPosition,
emojiContainer,
initialCategoryScrollPositions,
renderAtPosition
) => {
// Scope some local variables to track the scroll positions of the categories. We need to
// recalculate these because adding recent emojis can change those positions by adding
// additional rows.
let [
currentCategoryElement,
previousCategoryPosition,
nextCategoryPosition
] = getCategoryByScrollPosition(root, emojiContainer.scrollTop, initialCategoryScrollPositions);
return (categoryScrollPositions, rowData) => {
const newScrollPosition = emojiContainer.scrollTop;
const upperScrollBound = currentVisibleRowScrollPosition + ROW_HEIGHT_RAW;
const lowerScrollBound = currentVisibleRowScrollPosition - ROW_HEIGHT_RAW;
// We only need to update the active category indicator if the user has scrolled into a
// new category scroll position.
const updateActiveCategory = (newScrollPosition >= nextCategoryPosition) ||
(newScrollPosition < previousCategoryPosition);
// We only need to render new emoji rows if the user has scrolled far enough that a new row
// would be visible (i.e. they've scrolled up or down more than 40px - the height of a row).
const updateRenderRows = (newScrollPosition < lowerScrollBound) || (newScrollPosition > upperScrollBound);
if (updateActiveCategory) {
// New category is visible so update the active category selector and re-index the
// positions incase anything has changed.
[
currentCategoryElement,
previousCategoryPosition,
nextCategoryPosition
] = getCategoryByScrollPosition(root, newScrollPosition, categoryScrollPositions);
setCategorySelectorActive(root, currentCategoryElement);
}
if (updateRenderRows) {
// A new row should be visible so re-render the visible emojis at this new position.
// We request an animation frame from the browser so that we're not blocking anything.
// The animation only needs to occur as soon as the browser is ready not immediately.
requestAnimationFrame(() => {
renderAtPosition(newScrollPosition, rowData);
// Remember the updated position.
currentVisibleRowScrollPosition = newScrollPosition;
});
}
};
};
/**
* Build the function that handles search input from the user.
*
* @method
* @param {Element} searchInput The search input element
* @param {Element} searchResultsContainer Container element to display the search results
* @param {Element} emojiContainer Container element for the emoji rows
* @return {Function}
*/
const getHandleSearch = (searchInput, searchResultsContainer, emojiContainer) => {
const rowContainer = searchResultsContainer.querySelector(SELECTORS.ROW_CONTAINER);
// Build a render function for the search results.
const renderSearchResultsAtPosition = generateRenderRowsAtPositionFunction(rowContainer);
searchResultsContainer.appendChild(rowContainer);
return async() => {
const searchTerm = searchInput.value.toLowerCase();
if (searchTerm) {
// Display the search results container and hide the emojis container.
showSearchResults(emojiContainer, searchResultsContainer);
// Find which emojis match the user's search input.
const matchingEmojis = Object.keys(EmojiData.byShortName).reduce((carry, shortName) => {
if (shortName.includes(searchTerm)) {
carry.push({
shortnames: [shortName],
unified: EmojiData.byShortName[shortName]
});
}
return carry;
}, []);
const searchResultsString = await getString('searchresults', 'core');
const rowData = createRowDataForCategory(searchResultsString, searchResultsString, matchingEmojis, 0);
// Show the emoji rows for the search results.
renderSearchResultsAtPosition(0, rowData, rowData.length);
} else {
// Hide the search container and show the emojis container.
clearSearch(emojiContainer, searchResultsContainer, searchInput);
}
};
};
/**
* Register the emoji picker event listeners.
*
* @method
* @param {Element} root The picker root element
* @param {Element} emojiContainer Root element containing the list of visible emojis
* @param {Function} renderAtPosition Function to render the visible emojis at a given scroll position
* @param {Number} currentVisibleRowScrollPosition What is the current scroll position
* @param {Function} selectCallback Function to execute when the user picks an emoji
* @param {Object} categoryScrollPositions Scroll positions for where each of the emoji categories begin
* @param {Array} rowData Data representing each of the display rows for hte emoji container
* @param {Number} recentEmojiRowCount Number of rows of recent emojis
*/
const registerEventListeners = (
root,
emojiContainer,
renderAtPosition,
currentVisibleRowScrollPosition,
selectCallback,
categoryScrollPositions,
rowData,
recentEmojiRowCount
) => {
const searchInput = root.querySelector(SELECTORS.SEARCH_INPUT);
const searchResultsContainer = root.querySelector(SELECTORS.SEARCH_RESULTS_CONTAINER);
const emojiPreview = root.querySelector(SELECTORS.EMOJI_PREVIEW);
const emojiShortName = root.querySelector(SELECTORS.EMOJI_SHORT_NAME);
// Build the click handler function.
const clickHandler = getHandleClick(
recentEmojiRowCount,
emojiContainer,
searchResultsContainer,
searchInput,
selectCallback,
renderAtPosition
);
// Build the scroll handler function.
const scrollHandler = getHandleScroll(
root,
currentVisibleRowScrollPosition,
emojiContainer,
categoryScrollPositions,
renderAtPosition
);
const searchHandler = getHandleSearch(searchInput, searchResultsContainer, emojiContainer);
// Mouse enter/leave events to show the emoji preview on hover or focus.
root.addEventListener('focus', getHandleMouseEnter(emojiPreview, emojiShortName), true);
root.addEventListener('blur', getHandleMouseLeave(emojiPreview, emojiShortName), true);
root.addEventListener('mouseenter', getHandleMouseEnter(emojiPreview, emojiShortName), true);
root.addEventListener('mouseleave', getHandleMouseLeave(emojiPreview, emojiShortName), true);
// User selects an emoji or clicks on one of the emoji category selectors.
root.addEventListener('click', e => {
// Update the row data and category scroll positions because they may have changes if the
// user selects an emoji which updates the recent emojis list.
[rowData, categoryScrollPositions] = clickHandler(e, rowData, categoryScrollPositions);
});
// Throttle the scroll event to only execute once every 50 milliseconds to prevent performance issues
// in the browser when re-rendering the picker emojis. The scroll event fires a lot otherwise.
emojiContainer.addEventListener('scroll', throttle(() => scrollHandler(categoryScrollPositions, rowData), 50));
// Debounce the search input so that it only executes 200 milliseconds after the user has finished typing.
searchInput.addEventListener('input', debounce(searchHandler, 200));
};
/**
* Initialise the emoji picker.
*
* @method
* @param {Element} root The root element for the picker
* @param {Function} selectCallback Callback for when the user selects an emoji
*/
export default (root, selectCallback) => {
const emojiContainer = root.querySelector(SELECTORS.EMOJIS_CONTAINER);
const rowContainer = emojiContainer.querySelector(SELECTORS.ROW_CONTAINER);
const recentEmojis = getRecentEmojis();
// Add the recent emojis category to the list of standard categories.
const allData = [{
name: 'Recent',
emojis: recentEmojis
}, ...EmojiData.byCategory];
let rowData = [];
let recentEmojiRowCount = 0;
/**
* Split categories data into rows which represent how they will be displayed in the
* picker. Each category will add a row containing the display name for the category
* and a row for every 9 emojis in the category. The row data will be used to calculate
* which emojis should be visible in the picker at any given time.
*
* E.g.
* input = [
* {name: 'example1', emojis: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]},
* {name: 'example2', emojis: [13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23]},
* ]
* output = [
* {type: 'categoryName': data: 'Example 1'},
* {type: 'emojiRow': data: [1, 2, 3, 4, 5, 6, 7, 8, 9]},
* {type: 'emojiRow': data: [10, 11, 12]},
* {type: 'categoryName': data: 'Example 2'},
* {type: 'emojiRow': data: [13, 14, 15, 16, 17, 18, 19, 20, 21]},
* {type: 'emojiRow': data: [22, 23]},
* ]
*/
allData.forEach(category => {
const categorySelector = getCategorySelectorByCategoryName(root, category.name);
// Get the display name from the category selector button so that we don't need to
// send an ajax request for the string.
const categoryDisplayName = categorySelector.title;
const categoryRowData = createRowDataForCategory(category.name, categoryDisplayName, category.emojis, rowData.length);
if (category.name === 'Recent') {
// Remember how many recent emoji rows there are because it needs to be used to
// re-index the row data later when we're adding more recent emojis.
recentEmojiRowCount = categoryRowData.length;
}
rowData = rowData.concat(categoryRowData);
});
// Index the row data so that we can calculate which rows should be visible.
rowData = addIndexesToRowData(rowData);
// Calculate the scroll positions for each of the categories within the emoji container.
// These are used to know where to jump to when the user selects a specific category.
const categoryScrollPositions = getCategoryScrollPositionsFromRowData(rowData);
const renderAtPosition = generateRenderRowsAtPositionFunction(rowContainer);
// Display the initial set of emojis.
renderAtPosition(0, rowData);
registerEventListeners(
root,
emojiContainer,
renderAtPosition,
0,
selectCallback,
categoryScrollPositions,
rowData,
recentEmojiRowCount
);
};