GH-4095 Favorite/Starred Channels (#4222)

2 files changed, 136 insertions, 0 deletions

diff --git a/webapp/utils/channel_utils.jsx b/webapp/utils/channel_utils.jsx
new file mode 100644
index 000000000..119021fce
--- /dev/null
+++ b/webapp/utils/channel_utils.jsx
@@ -0,0 +1,135 @@
+
+import Constants from 'utils/constants.jsx';
+const Preferences = Constants.Preferences;
+
+import * as Utils from 'utils/utils.jsx';
+
+import UserStore from 'stores/user_store.jsx';
+import TeamStore from 'stores/team_store.jsx';
+import PreferenceStore from 'stores/preference_store.jsx';
+import LocalizationStore from 'stores/localization_store.jsx';
+
+/**
+ * Returns list of sorted channels grouped by type. Favorites here is considered as separated type.
+ *
+ * Example: {
+ *  publicChannels: [...],
+ *  privateChannels: [...],
+ *  directChannels: [...],
+ *  directNonTeamChannels: [...],
+ *  favoriteChannels: [...]
+ * }
+ */
+export function buildDisplayableChannelList(persistentChannels) {
+    const missingDMChannels = createMissingDirectChannels(persistentChannels);
+
+    const channels = persistentChannels.concat(missingDMChannels).map(completeDirectChannelInfo);
+    channels.sort(sortChannelsByDisplayName);
+
+    const favoriteChannels = channels.filter(isFavoriteChannel);
+    const notFavoriteChannels = channels.filter(not(isFavoriteChannel));
+    const directChannels = notFavoriteChannels.filter(andX(isDirectChannel, isDirectChannelVisible));
+
+    return {
+        favoriteChannels,
+        publicChannels: notFavoriteChannels.filter(isOpenChannel),
+        privateChannels: notFavoriteChannels.filter(isPrivateChannel),
+        directChannels: directChannels.filter(isConnectedToTeamMember),
+        directNonTeamChannels: directChannels.filter(not(isConnectedToTeamMember))
+    };
+}
+
+export function isFavoriteChannel(channel) {
+    return PreferenceStore.getBool(Preferences.CATEGORY_FAVORITE_CHANNEL, channel.id);
+}
+
+export function isOpenChannel(channel) {
+    return channel.type === Constants.OPEN_CHANNEL;
+}
+
+export function isPrivateChannel(channel) {
+    return channel.type === Constants.PRIVATE_CHANNEL;
+}
+
+export function isDirectChannel(channel) {
+    return channel.type === Constants.DM_CHANNEL;
+}
+
+export function isDirectChannelVisible(channel) {
+    const channelId = Utils.getUserIdFromChannelName(channel);
+
+    return PreferenceStore.getBool(Preferences.CATEGORY_DIRECT_CHANNEL_SHOW, channelId);
+}
+
+export function completeDirectChannelInfo(channel) {
+    if (!isDirectChannel(channel)) {
+        return channel;
+    }
+
+    const dmChannelClone = JSON.parse(JSON.stringify(channel));
+    const teammateId = Utils.getUserIdFromChannelName(channel);
+
+    return Object.assign(dmChannelClone, {
+        display_name: Utils.displayUsername(teammateId),
+        teammate_id: teammateId,
+        status: UserStore.getStatus(teammateId) || 'offline'
+    });
+}
+
+export function sortChannelsByDisplayName(a, b) {
+    const locale = LocalizationStore.getLocale();
+
+    return buildDisplayNameAndTypeComparable(a).localeCompare(buildDisplayNameAndTypeComparable(b), locale, {numeric: true});
+}
+
+/*
+ * not exported helpers
+ */
+
+function createMissingDirectChannels(channels) {
+    const directChannelsDisplayPreferences = PreferenceStore.getCategory(Preferences.CATEGORY_DIRECT_CHANNEL_SHOW);
+
+    return Array.
+        from(directChannelsDisplayPreferences).
+        filter((entry) => entry[1] === 'true').
+        map((entry) => entry[0]).
+        filter((teammateId) => !channels.some(Utils.isDirectChannelForUser.bind(null, teammateId))).
+        map(createFakeChannelCurried(UserStore.getCurrentId()));
+}
+
+function createFakeChannel(userId, otherUserId) {
+    return {
+        name: Utils.getDirectChannelName(userId, otherUserId),
+        last_post_at: 0,
+        total_msg_count: 0,
+        type: Constants.DM_CHANNEL,
+        fake: true
+    };
+}
+
+function createFakeChannelCurried(userId) {
+    return (otherUserId) => createFakeChannel(userId, otherUserId);
+}
+
+function isConnectedToTeamMember(channel) {
+    return isTeamMember(channel.teammate_id);
+}
+
+function isTeamMember(userId) {
+    return TeamStore.hasActiveMemberInTeam(TeamStore.getCurrentId(), userId);
+}
+
+function not(f) {
+    return (...args) => !f(...args);
+}
+
+function andX(...fns) {
+    return (...args) => fns.every((f) => f(...args));
+}
+
+const defaultPrefix = 'D'; // fallback for future types
+const typeToPrefixMap = {[Constants.OPEN_CHANNEL]: 'A', [Constants.PRIVATE_CHANNEL]: 'B', [Constants.DM_CHANNEL]: 'C'};
+
+function buildDisplayNameAndTypeComparable(channel) {
+    return (typeToPrefixMap[channel.type] || defaultPrefix) + channel.display_name + channel.name;
+}
diff --git a/webapp/utils/constants.jsx b/webapp/utils/constants.jsx
index 2dae06282..f87b36fc8 100644
--- a/webapp/utils/constants.jsx
+++ b/webapp/utils/constants.jsx
@@ -54,6 +54,7 @@ export const Preferences = {
     CATEGORY_THEME: 'theme',
     CATEGORY_FLAGGED_POST: 'flagged_post',
     CATEGORY_NOTIFICATIONS: 'notifications',
+    CATEGORY_FAVORITE_CHANNEL: 'favorite_channel',
     EMAIL_INTERVAL: 'email_interval'
 };