initial pseudocode WIP for e2e online backups

src/components/views/dialogs/SuggestKeyBackupDialog.js

@@ -0,0 +1,68 @@
+/*
+Copyright 2018 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import Modal from '../../../Modal';
+import React from 'react';
+import PropTypes from 'prop-types';
+import sdk from '../../../index';
+
+import { _t, _td } from '../../../languageHandler';
+
+/**
+ * Dialog which asks the user whether they want to restore megolm keys
+ * from various sources when they first start using E2E on a new device.
+ */
+export default React.createClass({
+    propTypes: {
+        onStartNewBackup: PropTypes.func.isRequired,
+    },
+
+    render: function() {
+        const BaseDialog = sdk.getComponent('views.dialogs.BaseDialog');
+
+        return (
+            <BaseDialog className='mx_SuggestKeyRestoreDialog'
+                onFinished={this.props.onFinished}
+                title={_t('Backup encryption keys on your server?')}
+            >
+            <div>
+                <p>To avoid ever losing your encrypted message history, you
+                can save your encryption keys on the server, protected by a recovery key.
+                </p>
+                <p>To maximise security, your recovery key is never stored by the app,
+                so you must store it yourself somewhere safe.</p>
+                <p>
+                <p>Warning: storing your encryption keys on the server means that
+                if someone gains access to your account and also steals your recovery key,
+                they will be able to read all of your encrypted conversation history.
+                </p>
+
+                <p>Do you wish to generate a recovery key and backup your encryption
+                keys on the server?
+
+                <div className="mx_Dialog_buttons">
+                    <button onClick={this.props.onStartNewBackup}>
+                        { _t("Generate recovery key and enable online backups") }
+                    </button>
+                    <button onClick={this.props.onFinished}>
+                        { _t("I'll stick to manual backups") }
+                    </button>
+                </div>
+            </div>
+            </BaseDialog>
+        );
+    },
+});