From d36b5bd0b050f8f3017795c3495eb6bf5ef995b7 Mon Sep 17 00:00:00 2001
From: David Joy <djoy@edx.org>
Date: Wed, 15 Jan 2020 13:59:05 -0500
Subject: [PATCH] Adding user-messages module and implementing course-level
 messaging.

---
 package.json                                |  1 +
 src/index.jsx                               | 21 ++++---
 src/learning-sequence/course/Course.jsx     |  2 +
 src/learning-sequence/sequence/Sequence.jsx | 32 +++++------
 src/user-messages/Alert.jsx                 | 63 +++++++++++++++++++++
 src/user-messages/AlertList.jsx             | 34 +++++++++++
 src/user-messages/UserMessagesContext.js    |  5 ++
 src/user-messages/UserMessagesProvider.jsx  | 44 ++++++++++++++
 8 files changed, 177 insertions(+), 25 deletions(-)
 create mode 100644 src/user-messages/Alert.jsx
 create mode 100644 src/user-messages/AlertList.jsx
 create mode 100644 src/user-messages/UserMessagesContext.js
 create mode 100644 src/user-messages/UserMessagesProvider.jsx

diff --git a/package.json b/package.json
index 71c4b6de..9beca094 100644
--- a/package.json
+++ b/package.json
@@ -43,6 +43,7 @@
     "@fortawesome/free-regular-svg-icons": "^5.12.0",
     "@fortawesome/free-solid-svg-icons": "^5.12.0",
     "@fortawesome/react-fontawesome": "^0.1.8",
+    "classnames": "^2.2.6",
     "core-js": "^3.6.2",
     "prop-types": "^15.7.2",
     "react": "^16.12.0",
diff --git a/src/index.jsx b/src/index.jsx
index a62e3b69..55fa01e4 100755
--- a/src/index.jsx
+++ b/src/index.jsx
@@ -13,6 +13,7 @@ import Footer, { messages as footerMessages } from '@edx/frontend-component-foot
 import appMessages from './i18n';
 import CourseTabsNavigation from './components/CourseTabsNavigation';
 import LearningSequencePage from './learning-sequence/LearningSequencePage';
+import UserMessagesProvider from './user-messages/UserMessagesProvider';
 
 import './index.scss';
 import './assets/favicon.ico';
@@ -31,15 +32,17 @@ function courseLinks() {
 subscribe(APP_READY, () => {
   ReactDOM.render(
     <AppProvider>
-      <Header />
-      <div className="container pt-2">
-        <CourseTabsNavigation activeTabSlug="course" />
-      </div>
-      <Switch>
-        <Route exact path="/" render={courseLinks} />
-        <Route path="/course" component={LearningSequencePage} />
-      </Switch>
-      <Footer />
+      <UserMessagesProvider>
+        <Header />
+        <div className="container pt-2">
+          <CourseTabsNavigation activeTabSlug="course" />
+        </div>
+        <Switch>
+          <Route exact path="/" render={courseLinks} />
+          <Route path="/course" component={LearningSequencePage} />
+        </Switch>
+        <Footer />
+      </UserMessagesProvider>
     </AppProvider>,
     document.getElementById('root'),
   );
diff --git a/src/learning-sequence/course/Course.jsx b/src/learning-sequence/course/Course.jsx
index c21fa179..c2bc7e9c 100644
--- a/src/learning-sequence/course/Course.jsx
+++ b/src/learning-sequence/course/Course.jsx
@@ -5,6 +5,7 @@ import { history } from '@edx/frontend-platform';
 import CourseBreadcrumbs from './CourseBreadcrumbs';
 import SequenceContainer from './SequenceContainer';
 import { createSequenceIdList } from '../utils';
+import AlertList from '../../user-messages/AlertList';
 
 export default function Course({
   courseUsageKey, courseId, sequenceId, unitId, models,
@@ -33,6 +34,7 @@ export default function Course({
 
   return (
     <main className="container-fluid d-flex flex-column flex-grow-1">
+      <AlertList topic="course" className="mt-3" />
       <CourseBreadcrumbs
         courseUsageKey={courseUsageKey}
         courseId={courseId}
diff --git a/src/learning-sequence/sequence/Sequence.jsx b/src/learning-sequence/sequence/Sequence.jsx
index f4fe1b44..a935f72e 100644
--- a/src/learning-sequence/sequence/Sequence.jsx
+++ b/src/learning-sequence/sequence/Sequence.jsx
@@ -118,29 +118,29 @@ function Sequence({
 }
 
 Sequence.propTypes = {
-  id: PropTypes.string.isRequired,
+  activeUnitId: PropTypes.string.isRequired,
+  bannerText: PropTypes.string,
   courseUsageKey: PropTypes.string.isRequired,
+  displayName: PropTypes.string.isRequired,
+  id: PropTypes.string.isRequired,
+  intl: intlShape.isRequired,
+  isGated: PropTypes.bool.isRequired,
+  isTimeLimited: PropTypes.bool.isRequired,
+  onNavigateUnit: PropTypes.func,
+  onNext: PropTypes.func.isRequired,
+  onPrevious: PropTypes.func.isRequired,
+  savePosition: PropTypes.bool.isRequired,
+  showCompletion: PropTypes.bool.isRequired,
+  prerequisite: PropTypes.shape({
+    name: PropTypes.string,
+    id: PropTypes.string,
+  }).isRequired,
   unitIds: PropTypes.arrayOf(PropTypes.string).isRequired,
   units: PropTypes.objectOf(PropTypes.shape({
     id: PropTypes.string.isRequired,
     complete: PropTypes.bool,
     pageTitle: PropTypes.string.isRequired,
   })).isRequired,
-  displayName: PropTypes.string.isRequired,
-  activeUnitId: PropTypes.string.isRequired,
-  showCompletion: PropTypes.bool.isRequired,
-  isTimeLimited: PropTypes.bool.isRequired,
-  bannerText: PropTypes.string,
-  onNext: PropTypes.func.isRequired,
-  onPrevious: PropTypes.func.isRequired,
-  onNavigateUnit: PropTypes.func,
-  isGated: PropTypes.bool.isRequired,
-  prerequisite: PropTypes.shape({
-    name: PropTypes.string,
-    id: PropTypes.string,
-  }).isRequired,
-  savePosition: PropTypes.bool.isRequired,
-  intl: intlShape.isRequired,
 };
 
 Sequence.defaultProps = {
diff --git a/src/user-messages/Alert.jsx b/src/user-messages/Alert.jsx
new file mode 100644
index 00000000..dda6f992
--- /dev/null
+++ b/src/user-messages/Alert.jsx
@@ -0,0 +1,63 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import classNames from 'classnames';
+import { faExclamationTriangle, faInfoCircle, faCheckCircle, faMinusCircle, faTimes } from '@fortawesome/free-solid-svg-icons';
+import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
+import { Button } from '@edx/paragon';
+
+function getAlertClass(type) {
+  if (type === 'error') {
+    return 'alert-warning';
+  } else if (type === 'danger') {
+    return 'alert-danger';
+  } else if (type === 'success') {
+    return 'alert-success';
+  }
+  return 'alert-info';
+}
+
+function getAlertIcon(type) {
+  if (type === 'error') {
+    return faExclamationTriangle;
+  } else if (type === 'danger') {
+    return faMinusCircle;
+  } else if (type === 'success') {
+    return faCheckCircle;
+  }
+  return faInfoCircle;
+}
+
+function Alert({
+  type, dismissible, children, onDismiss,
+}) {
+  return (
+    <div className={classNames('alert', { 'alert-dismissible': dismissible }, getAlertClass(type))}>
+      <div className="d-flex align-items-start">
+        <div className="mr-2">
+          <FontAwesomeIcon icon={getAlertIcon(type)} />
+        </div>
+        <div role="alert" className="flex-grow-1">
+          {children}
+        </div>
+      </div>
+      {dismissible && <Button className="close" onClick={onDismiss}><FontAwesomeIcon size="sm" icon={faTimes} /></Button>}
+    </div>
+  );
+}
+
+
+Alert.propTypes = {
+  type: PropTypes.oneOf(['error', 'danger', 'info', 'success']).isRequired,
+  dismissible: PropTypes.bool,
+  children: PropTypes.node,
+  onDismiss: PropTypes.func,
+};
+
+Alert.defaultProps = {
+  dismissible: false,
+  children: undefined,
+  onDismiss: null,
+};
+
+
+export default Alert;
diff --git a/src/user-messages/AlertList.jsx b/src/user-messages/AlertList.jsx
new file mode 100644
index 00000000..3b398ecd
--- /dev/null
+++ b/src/user-messages/AlertList.jsx
@@ -0,0 +1,34 @@
+import React, { useContext } from 'react';
+import PropTypes from 'prop-types';
+
+import UserMessagesContext from './UserMessagesContext';
+import Alert from './Alert';
+
+export default function AlertList({ topic, className }) {
+  const { remove, messages } = useContext(UserMessagesContext);
+
+  return (
+    <div className={className}>
+      {messages.filter(message => !topic || message.topic === topic).map(message => (
+        <Alert
+          key={message.id}
+          type={message.type}
+          dismissible={message.dismissible}
+          onDismiss={() => remove(message.id)}
+        >
+          {message.text}
+        </Alert>
+      ))}
+    </div>
+  );
+}
+
+AlertList.propTypes = {
+  className: PropTypes.string,
+  topic: PropTypes.string,
+};
+
+AlertList.defaultProps = {
+  topic: null,
+  className: null,
+};
diff --git a/src/user-messages/UserMessagesContext.js b/src/user-messages/UserMessagesContext.js
new file mode 100644
index 00000000..490e34dd
--- /dev/null
+++ b/src/user-messages/UserMessagesContext.js
@@ -0,0 +1,5 @@
+import React from 'react';
+
+const UserMessagesContext = React.createContext({});
+
+export default UserMessagesContext;
diff --git a/src/user-messages/UserMessagesProvider.jsx b/src/user-messages/UserMessagesProvider.jsx
new file mode 100644
index 00000000..1129c573
--- /dev/null
+++ b/src/user-messages/UserMessagesProvider.jsx
@@ -0,0 +1,44 @@
+import React, { useState } from 'react';
+import PropTypes from 'prop-types';
+
+import UserMessagesContext from './UserMessagesContext';
+
+export default function UserMessagesProvider({ children }) {
+  const [messages, setMessages] = useState([
+    {
+      code: null,
+      dismissible: true,
+      id: 0,
+      text: 'This is a course level message.',
+      type: 'info',
+      topic: 'course',
+    },
+  ]);
+  const [nextId, setNextId] = useState(1);
+
+  const add = (message) => {
+    setMessages([...messages, { ...message, id: nextId }]);
+    setNextId(nextId + 1);
+  };
+  const remove = id => setMessages(messages.filter(message => message.id !== id));
+
+  const value = {
+    add,
+    remove,
+    messages,
+  };
+
+  return (
+    <UserMessagesContext.Provider value={value}>
+      {children}
+    </UserMessagesContext.Provider>
+  );
+}
+
+UserMessagesProvider.propTypes = {
+  children: PropTypes.node,
+};
+
+UserMessagesProvider.defaultProps = {
+  children: null,
+};