From 097e8d2a87e903e2d12362f1dbe0f64a1df868b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miroslav=20=C5=A0ediv=C3=BD?= <sedivy.miro@gmail.com>
Date: Fri, 12 Nov 2021 15:27:05 +0000
Subject: [PATCH] Inactive cursors - multiple positions.

---
 internal/session/manager.go        | 16 +++++++++++-----
 internal/types/message/messages.go |  7 +++----
 internal/types/session.go          |  6 +++---
 internal/websocket/manager.go      | 19 +++++++++----------
 4 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/internal/session/manager.go b/internal/session/manager.go
index f94e2131..492e5fbd 100644
--- a/internal/session/manager.go
+++ b/internal/session/manager.go
@@ -19,7 +19,7 @@ func New(config *config.Session) *SessionManagerCtx {
 		config:   config,
 		tokens:   make(map[string]string),
 		sessions: make(map[string]*SessionCtx),
-		cursors:  make(map[types.Session]types.Cursor),
+		cursors:  make(map[types.Session][]types.Cursor),
 		emmiter:  events.New(),
 	}
 
@@ -56,7 +56,7 @@ type SessionManagerCtx struct {
 	host   types.Session
 	hostMu sync.Mutex
 
-	cursors   map[types.Session]types.Cursor
+	cursors   map[types.Session][]types.Cursor
 	cursorsMu sync.Mutex
 
 	emmiter    events.EventEmmiter
@@ -205,15 +205,21 @@ func (manager *SessionManagerCtx) SetCursor(cursor types.Cursor, session types.S
 	manager.cursorsMu.Lock()
 	defer manager.cursorsMu.Unlock()
 
-	manager.cursors[session] = cursor
+	list, ok := manager.cursors[session]
+	if !ok {
+		list = []types.Cursor{}
+	}
+
+	list = append(list, cursor)
+	manager.cursors[session] = list
 }
 
-func (manager *SessionManagerCtx) PopCursors() map[types.Session]types.Cursor {
+func (manager *SessionManagerCtx) PopCursors() map[types.Session][]types.Cursor {
 	manager.cursorsMu.Lock()
 	defer manager.cursorsMu.Unlock()
 
 	cursors := manager.cursors
-	manager.cursors = make(map[types.Session]types.Cursor)
+	manager.cursors = make(map[types.Session][]types.Cursor)
 
 	return cursors
 }
diff --git a/internal/types/message/messages.go b/internal/types/message/messages.go
index f6f00254..0365ea86 100644
--- a/internal/types/message/messages.go
+++ b/internal/types/message/messages.go
@@ -88,10 +88,9 @@ type SessionData struct {
 	State   types.SessionState  `json:"state"`
 }
 
-type SessionCursor struct {
-	ID string `json:"id"`
-	X  uint16 `json:"x"`
-	Y  uint16 `json:"y"`
+type SessionCursors struct {
+	ID      string         `json:"id"`
+	Cursors []types.Cursor `json:"cursors"`
 }
 
 /////////////////////////////
diff --git a/internal/types/session.go b/internal/types/session.go
index e8a6ed64..8bc0f3a4 100644
--- a/internal/types/session.go
+++ b/internal/types/session.go
@@ -13,8 +13,8 @@ var (
 )
 
 type Cursor struct {
-	X int
-	Y int
+	X int `json:"x"`
+	Y int `json:"y"`
 }
 
 type SessionState struct {
@@ -56,7 +56,7 @@ type SessionManager interface {
 	ClearHost()
 
 	SetCursor(cursor Cursor, session Session)
-	PopCursors() map[Session]Cursor
+	PopCursors() map[Session][]Cursor
 
 	Broadcast(event string, payload interface{}, exclude interface{})
 	AdminBroadcast(event string, payload interface{}, exclude interface{})
diff --git a/internal/websocket/manager.go b/internal/websocket/manager.go
index a753d23a..f0aa2559 100644
--- a/internal/websocket/manager.go
+++ b/internal/websocket/manager.go
@@ -21,7 +21,7 @@ import (
 const pingPeriod = 10 * time.Second
 
 // period for sending inactive cursor messages
-const inactiveCursorsPeriod = 500 * time.Millisecond
+const inactiveCursorsPeriod = 750 * time.Millisecond
 
 func New(
 	sessions types.SessionManager,
@@ -326,19 +326,18 @@ func (manager *WebSocketManagerCtx) inactiveCursors() {
 				}
 				lastEmpty = currentEmpty
 
-				cursors := []message.SessionCursor{}
-				for session, cursor := range cursorsMap {
-					cursors = append(
-						cursors,
-						message.SessionCursor{
-							ID: session.ID(),
-							X:  uint16(cursor.X),
-							Y:  uint16(cursor.Y),
+				sessionCursors := []message.SessionCursors{}
+				for session, cursors := range cursorsMap {
+					sessionCursors = append(
+						sessionCursors,
+						message.SessionCursors{
+							ID:      session.ID(),
+							Cursors: cursors,
 						},
 					)
 				}
 
-				manager.sessions.InactiveCursorsBroadcast(event.SESSION_CURSORS, cursors, nil)
+				manager.sessions.InactiveCursorsBroadcast(event.SESSION_CURSORS, sessionCursors, nil)
 			}
 		}
 	}()