Rewire the Sticker button to be an Emoji Picker

res/css/views/rooms/_MessageComposer.scss

@@ -214,8 +214,12 @@ limitations under the License.
     mask-image: url('$(res)/img/feather-customised/video.svg');
 }
 
+.mx_MessageComposer_emoji::before {
+    mask-image: url('$(res)/img/feather-customised/emoji3.custom.svg');
+}
+
 .mx_MessageComposer_stickers::before {
-    mask-image: url('$(res)/img/feather-customised/face.svg');
+    mask-image: url('$(res)/img/feather-customised/sticker.custom.svg');
 }
 
 .mx_MessageComposer_formatting {

src/components/views/rooms/MessageComposer.js

@@ -27,6 +27,7 @@ import { makeRoomPermalink } from '../../../utils/permalinks/Permalinks';
 import ContentMessages from '../../../ContentMessages';
 import E2EIcon from './E2EIcon';
 import SettingsStore from "../../../settings/SettingsStore";
+import {aboveLeftOf, ContextMenu, ContextMenuButton, useContextMenu} from "../../structures/ContextMenu";
 
 function ComposerAvatar(props) {
     const MemberStatusMessageAvatar = sdk.getComponent('avatars.MemberStatusMessageAvatar');
@@ -103,6 +104,32 @@ HangupButton.propTypes = {
     roomId: PropTypes.string.isRequired,
 };
 
+const EmojiButton = ({addEmoji}) => {
+    const [menuDisplayed, button, openMenu, closeMenu] = useContextMenu();
+
+    let contextMenu;
+    if (menuDisplayed) {
+        const buttonRect = button.current.getBoundingClientRect();
+        const EmojiPicker = sdk.getComponent('emojipicker.EmojiPicker');
+        contextMenu = <ContextMenu {...aboveLeftOf(buttonRect)} onFinished={closeMenu} catchTab={false}>
+            <EmojiPicker onChoose={addEmoji} showQuickReactions={true} />
+        </ContextMenu>;
+    }
+
+    return <React.Fragment>
+        <ContextMenuButton className="mx_MessageComposer_button mx_MessageComposer_emoji"
+                           onClick={openMenu}
+                           isExpanded={menuDisplayed}
+                           label={_t('Emoji picker')}
+                           inputRef={button}
+        >
+
+        </ContextMenuButton>
+
+        { contextMenu }
+    </React.Fragment>;
+};
+
 class UploadButton extends React.Component {
     static propTypes = {
         roomId: PropTypes.string.isRequired,
@@ -312,6 +339,13 @@ export default class MessageComposer extends React.Component {
         }
     }
 
+    addEmoji(emoji) {
+        dis.dispatch({
+            action: "insert_emoji",
+            emoji,
+        });
+    }
+
     render() {
         const controls = [
             this.state.me ? <ComposerAvatar key="controls_avatar" me={this.state.me} /> : null,
@@ -335,8 +369,9 @@ export default class MessageComposer extends React.Component {
                     room={this.props.room}
                     placeholder={this.renderPlaceholderText()}
                     permalinkCreator={this.props.permalinkCreator} />,
-                <Stickerpicker key='stickerpicker_controls_button' room={this.props.room} />,
                 <UploadButton key="controls_upload" roomId={this.props.room.roomId} />,
+                <EmojiButton key="emoji_button" addEmoji={this.addEmoji} />,
+                <Stickerpicker key="stickerpicker_controls_button" room={this.props.room} />,
             );
 
             if (this.state.showCallButtons) {

src/components/views/rooms/SendMessageComposer.js

@@ -378,6 +378,9 @@ export default class SendMessageComposer extends React.Component {
             case 'quote':
                 this._insertQuotedMessage(payload.event);
                 break;
+            case 'insert_emoji':
+                this._insertEmoji(payload.emoji);
+                break;
         }
     };
 
@@ -415,6 +418,17 @@ export default class SendMessageComposer extends React.Component {
         this._editorRef && this._editorRef.focus();
     }
 
+    _insertEmoji = (emoji) => {
+        const {model} = this;
+        const {partCreator} = model;
+        const caret = this._editorRef.getCaret();
+        const position = model.positionForOffset(caret.offset, caret.atNodeEnd);
+        model.transform(() => {
+            const addedLen = model.insert([partCreator.plain(emoji)], position);
+            return model.positionForOffset(caret.offset + addedLen, true);
+        });
+    };
+
     _onPaste = (event) => {
         const {clipboardData} = event;
         if (clipboardData.files.length) {

src/i18n/strings/en_EN.json

@@ -1086,6 +1086,7 @@
     "Voice call": "Voice call",
     "Video call": "Video call",
     "Hangup": "Hangup",
+    "Emoji picker": "Emoji picker",
     "Upload file": "Upload file",
     "Send an encrypted reply…": "Send an encrypted reply…",
     "Send a reply…": "Send a reply…",