only show supported verification methods

also an error message if none match

src/components/views/right_panel/VerificationPanel.js

@@ -19,6 +19,8 @@ import PropTypes from "prop-types";
 
 import * as sdk from '../../../index';
 import {verificationMethods} from 'matrix-js-sdk/src/crypto';
+import {SCAN_QR_CODE_METHOD} from "matrix-js-sdk/src/crypto/verification/QRCode";
+
 import VerificationQRCode from "../elements/crypto/VerificationQRCode";
 import {_t} from "../../../languageHandler";
 import E2EIcon from "../rooms/E2EIcon";
@@ -54,8 +56,10 @@ export default class VerificationPanel extends React.PureComponent {
             qrCodeProps: null, // generated by the VerificationQRCode component itself
         };
         this._hasVerifier = false;
+        if (this.props.request.otherPartySupportsMethod(SCAN_QR_CODE_METHOD)) {
             this._generateQRCodeProps(props.request);
         }
+    }
 
     async _generateQRCodeProps(verificationRequest: VerificationRequest) {
         try {
@@ -67,36 +71,73 @@ export default class VerificationPanel extends React.PureComponent {
     }
 
     renderQRPhase(pending) {
-        const {member} = this.props;
+        const {member, request} = this.props;
+        const showSAS = request.methods.includes(verificationMethods.SAS);
+        const showQR = this.props.request.otherPartySupportsMethod(SCAN_QR_CODE_METHOD);
         const AccessibleButton = sdk.getComponent('elements.AccessibleButton');
 
+        const noCommonMethodError = !showSAS && !showQR ?
+            <p>{_t("The session you are trying to verify doesn't support scanning a QR code or emoji verification, which is what Riot supports. Try with a different client.")}</p> :
+            null;
+
         if (this.props.layout === 'dialog') {
             // HACK: This is a terrible idea.
-            let qrCode = <div className='mx_VerificationPanel_QRPhase_noQR'><Spinner /></div>;
+            let qrBlock;
+            let sasBlock;
+            if (showQR) {
+                let qrCode;
                 if (this.state.qrCodeProps) {
                     qrCode = <VerificationQRCode {...this.state.qrCodeProps} />;
+                } else {
+                    qrCode = <div className='mx_VerificationPanel_QRPhase_noQR'><Spinner /></div>;
                 }
-            return (
-                <div>
-                    {_t("Verify this session by completing one of the following:")}
-                    <div className='mx_VerificationPanel_QRPhase_startOptions'>
+                qrBlock =
                     <div className='mx_VerificationPanel_QRPhase_startOption'>
                         <p>{_t("Scan this unique code")}</p>
                         {qrCode}
-                        </div>
-                        <div className='mx_VerificationPanel_QRPhase_betweenText'>{_t("or")}</div>
+                    </div>;
+            }
+            if (showSAS) {
+                sasBlock =
                     <div className='mx_VerificationPanel_QRPhase_startOption'>
                         <p>{_t("Compare unique emoji")}</p>
                         <span className='mx_VerificationPanel_QRPhase_helpText'>{_t("Compare a unique set of emoji if you don't have a camera on either device")}</span>
                         <AccessibleButton disabled={this.state.emojiButtonClicked} onClick={this._startSAS} kind='primary'>
                             {_t("Start")}
                         </AccessibleButton>
-                        </div>
+                    </div>;
+            }
+            const or = qrBlock && sasBlock ?
+                <div className='mx_VerificationPanel_QRPhase_betweenText'>{_t("or")}</div> : null;
+            return (
+                <div>
+                    {_t("Verify this session by completing one of the following:")}
+                    <div className='mx_VerificationPanel_QRPhase_startOptions'>
+                        {qrBlock}
+                        {or}
+                        {sasBlock}
+                        {noCommonMethodError}
                     </div>
                 </div>
             );
         }
 
+        let qrBlock;
+        if (this.state.qrCodeProps) {
+            qrBlock = <div className="mx_UserInfo_container">
+                <h3>{_t("Verify by scanning")}</h3>
+                <p>{_t("Ask %(displayName)s to scan your code:", {
+                    displayName: member.displayName || member.name || member.userId,
+                })}</p>
+
+                <div className="mx_VerificationPanel_qrCode">
+                    <VerificationQRCode {...this.state.qrCodeProps} />
+                </div>
+            </div>;
+        }
+
+        let sasBlock;
+        if (showSAS) {
             let button;
             if (pending) {
                 button = <Spinner />;
@@ -108,34 +149,25 @@ export default class VerificationPanel extends React.PureComponent {
                     </AccessibleButton>
                 );
             }
-
-        if (!this.state.qrCodeProps) {
-            return <div className="mx_UserInfo_container">
+            const sasLabel = this.state.qrCodeProps ?
+                _t("If you can't scan the code above, verify by comparing unique emoji.") :
+                _t("Verify by comparing unique emoji.");
+            sasBlock = <div className="mx_UserInfo_container">
                 <h3>{_t("Verify by emoji")}</h3>
-                <p>{_t("Verify by comparing unique emoji.")}</p>
+                <p>{sasLabel}</p>
                 { button }
             </div>;
         }
 
+        const noCommonMethodBlock = noCommonMethodError ?
+             <div className="mx_UserInfo_container">{noCommonMethodError}</div> :
+             null;
+
         // TODO: add way to open camera to scan a QR code
         return <React.Fragment>
-            <div className="mx_UserInfo_container">
-                <h3>{_t("Verify by scanning")}</h3>
-                <p>{_t("Ask %(displayName)s to scan your code:", {
-                    displayName: member.displayName || member.name || member.userId,
-                })}</p>
-
-                <div className="mx_VerificationPanel_qrCode">
-                    <VerificationQRCode {...this.state.qrCodeProps} />
-                </div>
-            </div>
-
-            <div className="mx_UserInfo_container">
-                <h3>{_t("Verify by emoji")}</h3>
-                <p>{_t("If you can't scan the code above, verify by comparing unique emoji.")}</p>
-
-                { button }
-            </div>
+            {qrBlock}
+            {sasBlock}
+            {noCommonMethodBlock}
         </React.Fragment>;
     }
 

src/i18n/strings/en_EN.json

@@ -1197,11 +1197,12 @@
     "This client does not support end-to-end encryption.": "This client does not support end-to-end encryption.",
     "Messages in this room are not end-to-end encrypted.": "Messages in this room are not end-to-end encrypted.",
     "Security": "Security",
-    "Verify by emoji": "Verify by emoji",
-    "Verify by comparing unique emoji.": "Verify by comparing unique emoji.",
+    "The session you are trying to verify doesn't support scanning a QR code or emoji verification, which is what Riot supports. Try with a different client.": "The session you are trying to verify doesn't support scanning a QR code or emoji verification, which is what Riot supports. Try with a different client.",
     "Verify by scanning": "Verify by scanning",
     "Ask %(displayName)s to scan your code:": "Ask %(displayName)s to scan your code:",
+    "Verify by emoji": "Verify by emoji",
     "If you can't scan the code above, verify by comparing unique emoji.": "If you can't scan the code above, verify by comparing unique emoji.",
+    "Verify by comparing unique emoji.": "Verify by comparing unique emoji.",
     "You've successfully verified %(displayName)s!": "You've successfully verified %(displayName)s!",
     "Got it": "Got it",
     "Verification timed out. Start verification again from their profile.": "Verification timed out. Start verification again from their profile.",