big update: added reactions, groups, media share

server/internal/realtime/events.go

@@ -9,10 +9,16 @@ import (
 
 // Event type constants sent over the wire.
 const (
-	EventMessageCreated = "message.created"
-	EventTyping         = "typing"
-	EventPresence       = "presence"
-	EventRead           = "read"
+	EventMessageCreated      = "message.created"
+	EventTyping              = "typing"
+	EventPresence            = "presence"
+	EventRead                = "read"
+	EventConversationAdded   = "conversation.added"
+	EventConversationRemoved = "conversation.removed"
+	EventMemberAdded         = "member.added"
+	EventMemberRemoved       = "member.removed"
+	EventReactionAdded       = "reaction.added"
+	EventReactionRemoved     = "reaction.removed"
 )
 
 // Presence status values.
@@ -23,12 +29,24 @@ const (
 
 // MessageCreated is published when a message is stored.
 type MessageCreated struct {
-	TempID         string    `json:"temp_id,omitempty"`
-	ConversationID int64     `json:"conversation_id"`
-	MessageID      int64     `json:"message_id"`
-	SenderID       int64     `json:"sender_id"`
-	Body           string    `json:"body"`
-	CreatedAt      time.Time `json:"created_at"`
+	TempID         string     `json:"temp_id,omitempty"`
+	ConversationID int64      `json:"conversation_id"`
+	MessageID      int64      `json:"message_id"`
+	SenderID       int64      `json:"sender_id"`
+	Body           string     `json:"body"`
+	MediaID        *int64     `json:"media_id,omitempty"`
+	Media          *MediaInfo `json:"media,omitempty"`
+	CreatedAt      time.Time  `json:"created_at"`
+}
+
+// MediaInfo mirrors attachment metadata delivered with a message event.
+type MediaInfo struct {
+	ID          int64  `json:"id"`
+	Filename    string `json:"filename"`
+	ContentType string `json:"content_type"`
+	Size        int64  `json:"size"`
+	URL         string `json:"url"`
+	ThumbURL    string `json:"thumb_url,omitempty"`
 }
 
 // Typing is published when a user starts or stops typing in a conversation.
@@ -51,6 +69,25 @@ type Read struct {
 	MessageID      int64 `json:"message_id"`
 }
 
+// ConversationChanged is sent to a user when they gain or lose a conversation.
+type ConversationChanged struct {
+	ConversationID int64 `json:"conversation_id"`
+}
+
+// MemberChanged is published when a user joins or leaves a conversation.
+type MemberChanged struct {
+	ConversationID int64 `json:"conversation_id"`
+	UserID         int64 `json:"user_id"`
+}
+
+// ReactionChanged is published when a reaction is added to or removed from a message.
+type ReactionChanged struct {
+	ConversationID int64  `json:"conversation_id"`
+	MessageID      int64  `json:"message_id"`
+	UserID         int64  `json:"user_id"`
+	Emoji          string `json:"emoji"`
+}
+
 // envelope is the wire format for every message, both inbound and outbound.
 type envelope struct {
 	Type string          `json:"type"`

server/internal/realtime/hub.go

@@ -84,6 +84,67 @@ func (h *Hub) PublishRead(conversationID, userID, messageID int64) {
 	h.sendToConversation(conversationID, envelope{Type: EventRead, Data: mustMarshal(evt)}, userID)
 }
 
+// Subscribe adds a user to a conversation's subscriber set so they receive its
+// events without reconnecting (used when a member is added to a group).
+func (h *Hub) Subscribe(userID, conversationID int64) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if h.subs[conversationID] == nil {
+		h.subs[conversationID] = make(map[int64]struct{})
+	}
+	h.subs[conversationID][userID] = struct{}{}
+}
+
+// Unsubscribe removes a user from a conversation's subscriber set.
+func (h *Hub) Unsubscribe(userID, conversationID int64) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	users := h.subs[conversationID]
+	delete(users, userID)
+	if len(users) == 0 {
+		delete(h.subs, conversationID)
+	}
+}
+
+// SendToUser delivers an event to every connection of a single user.
+func (h *Hub) SendToUser(userID int64, evtType string, data any) {
+	payload, err := json.Marshal(envelope{Type: evtType, Data: mustMarshal(data)})
+	if err != nil {
+		slog.Error("ws: marshal direct event", "error", err)
+		return
+	}
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	for c := range h.conns[userID] {
+		c.enqueueRaw(payload)
+	}
+}
+
+// PublishMemberChanged tells a conversation's members that someone joined or left.
+func (h *Hub) PublishMemberChanged(conversationID, userID int64, added bool) {
+	evtType := EventMemberAdded
+	if !added {
+		evtType = EventMemberRemoved
+	}
+	evt := MemberChanged{ConversationID: conversationID, UserID: userID}
+	h.sendToConversation(conversationID, envelope{Type: evtType, Data: mustMarshal(evt)}, 0)
+}
+
+// PublishReactionChanged tells a conversation's members that a reaction changed.
+func (h *Hub) PublishReactionChanged(conversationID, messageID, userID int64, emoji string, added bool) {
+	evtType := EventReactionAdded
+	if !added {
+		evtType = EventReactionRemoved
+	}
+	evt := ReactionChanged{
+		ConversationID: conversationID,
+		MessageID:      messageID,
+		UserID:         userID,
+		Emoji:          emoji,
+	}
+	h.sendToConversation(conversationID, envelope{Type: evtType, Data: mustMarshal(evt)}, 0)
+}
+
 func (h *Hub) register(c *client, conversationIDs []int64) {
 	h.mu.Lock()
 	defer h.mu.Unlock()