Make it clearer which HS you're logging into

Otherwise there's no indication without clicking 'custom server'

src/components/structures/login/Login.js

@@ -290,6 +290,7 @@ module.exports = React.createClass({
                         onPhoneNumberChanged={this.onPhoneNumberChanged}
                         onForgotPasswordClick={this.props.onForgotPasswordClick}
                         loginIncorrect={this.state.loginIncorrect}
+                        hsUrl={this.state.enteredHomeserverUrl}
                     />
                 );
             case 'm.login.cas':

src/components/views/elements/Dropdown.js

@@ -26,6 +26,12 @@ class MenuOption extends React.Component {
         this._onClick = this._onClick.bind(this);
     }
 
+    getDefaultProps() {
+        return {
+            disabled: false,
+        }
+    }
+
     _onMouseEnter() {
         this.props.onMouseEnter(this.props.dropdownKey);
     }
@@ -153,6 +159,8 @@ export default class Dropdown extends React.Component {
     }
 
     _onInputClick(ev) {
+        if (this.props.disabled) return;
+
         if (!this.state.expanded) {
             this.setState({
                 expanded: true,
@@ -329,4 +337,6 @@ Dropdown.propTypes = {
     // in the dropped-down menu.
     getShortOption: React.PropTypes.func,
     value: React.PropTypes.string,
+    // negative for consistency with HTML
+    disabled: React.PropTypes.bool,
 }

src/components/views/login/PasswordLogin.js

@@ -186,6 +186,17 @@ class PasswordLogin extends React.Component {
 
         const loginField = this.renderLoginField(this.state.loginType);
 
+        let matrixIdText = '';
+        if (this.props.hsUrl) {
+            try {
+                const parsedHsUrl = new URL(this.props.hsUrl);
+                matrixIdText = _t('%(serverName)s Matrix ID', {serverName: parsedHsUrl.hostname});
+            } catch (e) {
+                console.log(e);
+                // pass
+            }
+        }
+
         return (
             <div>
                 <form onSubmit={this.onSubmitForm}>
@@ -194,8 +205,9 @@ class PasswordLogin extends React.Component {
                     <Dropdown
                         className="mx_Login_type_dropdown"
                         value={this.state.loginType}
+                        disabled={matrixIdText === ''}
                         onOptionChange={this.onLoginTypeChange}>
-                            <span key={PasswordLogin.LOGIN_FIELD_MXID}>{ _t('my Matrix ID') }</span>
+                            <span key={PasswordLogin.LOGIN_FIELD_MXID}>{matrixIdText}</span>
                             <span key={PasswordLogin.LOGIN_FIELD_EMAIL}>{ _t('Email address') }</span>
                             <span key={PasswordLogin.LOGIN_FIELD_PHONE}>{ _t('Phone') }</span>
                     </Dropdown>

src/i18n/strings/en_EN.json

@@ -906,5 +906,6 @@
     "Related Groups": "Related Groups",
     "Related groups for this room:": "Related groups for this room:",
     "This room has no related groups": "This room has no related groups",
-    "New group ID (e.g. +foo:%(localDomain)s)": "New group ID (e.g. +foo:%(localDomain)s)"
+    "New group ID (e.g. +foo:%(localDomain)s)": "New group ID (e.g. +foo:%(localDomain)s)",
+    "%(serverName)s Matrix ID": "%(serverName)s Matrix ID"
 }