1 files changed, 69 insertions, 0 deletions
diff --git a/internal/chat/chan.go b/internal/chat/chan.go
new file mode 100644
index 0000000..ae78bb6
--- /dev/null
+++ b/internal/chat/chan.go
@@ -0,0 +1,69 @@
+package chat
+
+import (
+	"context"
+	"log/slog"
+	"sync"
+	"time"
+)
+
+type Channel struct {
+	Name   string
+	Users  map[*User]struct{}
+	Events chan any
+	mu     sync.RWMutex
+}
+
+func (c *Channel) Listen(ctx context.Context) {
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case ev := <-c.Events:
+			c.processEvent(ev)
+		}
+	}
+}
+
+func (c *Channel) processEvent(ev any) {
+	slog.Info("channel event", slog.String("channel", c.Name), slog.Any("event", ev))
+
+	for u := range c.Users {
+		select {
+		case u.Events <- ev:
+		default:
+		}
+	}
+}
+
+func (c *Channel) Join(u *User) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if _, ok := c.Users[u]; ok {
+		return
+	}
+	c.Events <- UserJoined{
+		User: u,
+		Time: time.Now(),
+		Chan: c,
+	}
+
+	c.Users[u] = struct{}{}
+}
+
+func (c *Channel) Leave(u *User) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if _, ok := c.Users[u]; !ok {
+		return
+	}
+	c.Events <- UserLeft{
+		User: u,
+		Time: time.Now(),
+		Chan: c,
+	}
+
+	delete(c.Users, u)
+}