From a16894a1b1274c7b1630630864a7e9127ea75e16 Mon Sep 17 00:00:00 2001
From: Noah Petherbridge <root@kirsle.net>
Date: Sun, 8 Oct 2023 13:35:11 -0700
Subject: [PATCH] Chat landing page: show online friends

---
 pkg/controller/chat/chat.go |  9 +++++++-
 pkg/models/friend.go        | 33 +++++++++++++++++++++++++++
 pkg/models/user.go          | 45 +++++++++++++++++++++++++++++++++++++
 web/templates/chat.html     | 15 ++++++++++++-
 4 files changed, 100 insertions(+), 2 deletions(-)

diff --git a/pkg/controller/chat/chat.go b/pkg/controller/chat/chat.go
index a352bf6..b4231e7 100644
--- a/pkg/controller/chat/chat.go
+++ b/pkg/controller/chat/chat.go
@@ -150,12 +150,19 @@ func Landing() http.HandlerFunc {
 			return
 		}
 
+		// Get the ChatStatistics and select our friend names from it.
+		var (
+			stats         = FilteredChatStatistics(currentUser)
+			friendsOnline = models.FilterFriendUsernames(currentUser, stats.Usernames)
+		)
+
 		var vars = map[string]interface{}{
 			"ChatAPI":   strings.TrimSuffix(config.Current.BareRTC.URL, "/") + "/api/statistics",
 			"IsShyUser": isShy,
 
 			// Pre-populate the "who's online" widget from backend cache data
-			"ChatStatistics": FilteredChatStatistics(currentUser),
+			"ChatStatistics": stats,
+			"FriendsOnline":  friendsOnline,
 		}
 		if err := tmpl.Execute(w, r, vars); err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
diff --git a/pkg/models/friend.go b/pkg/models/friend.go
index 6f49ea8..d0ae1fa 100644
--- a/pkg/models/friend.go
+++ b/pkg/models/friend.go
@@ -127,6 +127,39 @@ func FilterFriendIDs(userIDs []uint64, friendIDs []uint64) []uint64 {
 	return filtered
 }
 
+// FilterFriendUsernames takes a list of usernames and returns only the ones who are your friends.
+func FilterFriendUsernames(currentUser *User, usernames []string) []string {
+	var (
+		fs      = []*Friend{}
+		userIDs = []uint64{}
+		userMap = map[uint64]string{}
+		result  = []string{}
+	)
+
+	// Map usernames to user IDs.
+	users, err := GetUsersByUsernames(currentUser, usernames)
+	if err != nil {
+		log.Error("FilterFriendUsernames: GetUsersByUsernames: %s", err)
+		return result
+	}
+
+	for _, user := range users {
+		userIDs = append(userIDs, user.ID)
+		userMap[user.ID] = user.Username
+	}
+
+	if len(userIDs) == 0 {
+		return result
+	}
+
+	DB.Where("source_user_id = ? AND approved = ? AND target_user_id IN ?", currentUser.ID, true, userIDs).Find(&fs)
+	for _, row := range fs {
+		result = append(result, userMap[row.TargetUserID])
+	}
+
+	return result
+}
+
 // FriendIDsAreExplicit returns friend IDs who have opted-in for Explicit content,
 // e.g. to notify only them when you uploaded a new Explicit photo so that non-explicit
 // users don't need to see that notification.
diff --git a/pkg/models/user.go b/pkg/models/user.go
index f14fa41..c1853c1 100644
--- a/pkg/models/user.go
+++ b/pkg/models/user.go
@@ -124,6 +124,51 @@ func GetUsers(currentUser *User, userIDs []uint64) ([]*User, error) {
 	return users, nil
 }
 
+// GetUsersByUsernames queries for multiple usernames and returns users in the same order.
+func GetUsersByUsernames(currentUser *User, usernames []string) ([]*User, error) {
+	// Map the usernames.
+	var (
+		usermap  = map[string]*User{}
+		set      = map[string]interface{}{}
+		distinct = []string{}
+	)
+
+	// Uniqueify usernames.
+	for _, name := range usernames {
+		if _, ok := set[name]; ok {
+			continue
+		}
+		set[name] = nil
+		distinct = append(distinct, name)
+	}
+
+	var (
+		users  = []*User{}
+		result = (&User{}).Preload().Where("username IN ?", distinct).Find(&users)
+	)
+	if result.Error != nil {
+		return nil, result.Error
+	}
+
+	// Map users.
+	for _, user := range users {
+		usermap[user.Username] = user
+	}
+
+	// Inject relationships.
+	SetUserRelationships(currentUser, users)
+
+	// Re-order them per the original sequence.
+	var ordered = []*User{}
+	for _, name := range usernames {
+		if user, ok := usermap[name]; ok {
+			ordered = append(ordered, user)
+		}
+	}
+
+	return ordered, nil
+}
+
 // FindUser by username or email.
 func FindUser(username string) (*User, error) {
 	if username == "" {
diff --git a/web/templates/chat.html b/web/templates/chat.html
index 42c0e7f..7b50132 100644
--- a/web/templates/chat.html
+++ b/web/templates/chat.html
@@ -47,9 +47,22 @@
             <a id="whoLink" href="#" style="visibility: hidden">Who?</a>
             <span id="whoList" style="display: none"></span>
 
+            <!-- Friends online? -->
+            {{if .FriendsOnline}}
+            <div class="mt-2">
+                <i class="fa fa-user-group mr-1"></i>
+                <strong>{{len .FriendsOnline}} friend{{Pluralize (len .FriendsOnline)}}</strong>
+                {{Pluralize (len .FriendsOnline) "is" "are"}} currently online:
+                {{$FriendsOnline := .FriendsOnline}}
+                {{range $i, $name := .FriendsOnline -}}
+                    {{- if $i -}}, {{end}}<a href="/u/{{ $name }}">{{ $name }}</a>
+                {{- end}}
+            </div>
+            {{end}}
+
             <!-- Camera stats if active -->
             <div id="cameraStats" style="display: none" class="mt-2">
-                <i class="fa fa-camera"></i>
+                <i class="fa fa-camera mr-1"></i>
                 <span id="cameraCount">0 people are on camera</span>
                 <span class="is-size-7">
                     (<i class="fa fa-video has-text-info"></i> <span id="cameraBlue" class="has-text-info">0</span> /