Implement redesigned upload confirmation screens

Also fairly significant refactor of the uploading code: there are
a number of different ways of triggerring a file upload and each
went through a different code path (the media config size limit
worked on one of those paths). Basically take a lot of code out
of the views and put it into ContentMessages.

Sorry about the size of this patch.

https://github.com/vector-im/riot-web/issues/7565

src/components/views/dialogs/UploadFailureDialog.js

@@ -0,0 +1,120 @@
+/*
+Copyright 2019 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 filesize from 'filesize';
+
+import React from 'react';
+import PropTypes from 'prop-types';
+import sdk from '../../../index';
+import { _t } from '../../../languageHandler';
+import ContentMessages from '../../../ContentMessages';
+
+/*
+ * Tells the user about files we know cannot be uploaded before we even try uploading
+ * them. This is named fairly generically but the only thing we check right now is
+ * the size of the file.
+ */
+export default class UploadFailureDialog extends React.Component {
+    static propTypes = {
+        badFiles: PropTypes.arrayOf(PropTypes.object).isRequired,
+        totalFiles: PropTypes.number.isRequired,
+        contentMessages: PropTypes.instanceOf(ContentMessages).isRequired,
+        onFinished: PropTypes.func.isRequired,
+    }
+
+    _onCancelClick = () => {
+        this.props.onFinished(false);
+    }
+
+    _onUploadClick = () => {
+        this.props.onFinished(true);
+    }
+
+    render() {
+        const BaseDialog = sdk.getComponent('views.dialogs.BaseDialog');
+        const DialogButtons = sdk.getComponent('views.elements.DialogButtons');
+
+        let message;
+        let preview;
+        let buttons;
+        if (this.props.totalFiles === 1 && this.props.badFiles.length === 1) {
+            message = _t(
+                "This file is <b>too large</b> to upload. " +
+                "The file size limit is %(limit)s but this file is %(sizeOfThisFile)s.",
+                {
+                    limit: filesize(this.props.contentMessages.getUploadLimit()),
+                    sizeOfThisFile: filesize(this.props.badFiles[0].size),
+                }, {
+                    b: sub => <b>{sub}</b>,
+                },
+            );
+            buttons = <DialogButtons primaryButton={_t('OK')}
+                hasCancel={false}
+                onPrimaryButtonClick={this._onCancelClick}
+                focus={true}
+            />;
+        } else if (this.props.totalFiles === this.props.badFiles.length) {
+            message = _t(
+                "These files are <b>too large</b> to upload. " +
+                "The file size limit is %(limit)s.",
+                {
+                    limit: filesize(this.props.contentMessages.getUploadLimit()),
+                }, {
+                    b: sub => <b>{sub}</b>,
+                },
+            );
+            buttons = <DialogButtons primaryButton={_t('OK')}
+                hasCancel={false}
+                onPrimaryButtonClick={this._onCancelClick}
+                focus={true}
+            />;
+        } else {
+            message = _t(
+                "Some files are <b>too large</b> to be uploaded." +
+                "The file size limit is %(limit)s.",
+                {
+                    limit: filesize(this.props.contentMessages.getUploadLimit()),
+                }, {
+                    b: sub => <b>{sub}</b>,
+                },
+            );
+            const howManyOthers = this.props.totalFiles - this.props.badFiles.length;
+            buttons = <DialogButtons
+                primaryButton={_t('Upload %(count)s other files', { count: howManyOthers })}
+                onPrimaryButtonClick={this._onUploadClick}
+                hasCancel={true}
+                cancelButton={_t("Cancel All")}
+                onCancel={this._onCancelClick}
+                focus={true}
+            />;
+        }
+
+        return (
+            <BaseDialog className='mx_UploadFailureDialog'
+                onFinished={this._onCancelClick}
+                title={_t("Upload Error")}
+                contentId='mx_Dialog_content'
+            >
+                <div id='mx_Dialog_content'>
+                    {message}
+                    {preview}
+                </div>
+
+                {buttons}
+            </BaseDialog>
+        );
+    }
+}