From 884766dc72bd81af03f6a086ef70bd6e3196e3e1 Mon Sep 17 00:00:00 2001
From: Steve <stryan@saintnet.tech>
Date: Thu, 29 Jul 2021 17:40:11 -0400
Subject: [PATCH] opt into polling, clients no longer crash on leave

---
 cmd/client2/backend.go              | 27 +++++++++++++++++----------
 cmd/server/server.go                |  2 ++
 internal/coordinator/coordinator.go |  7 ++++++-
 internal/coordinator/session.go     |  2 --
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/cmd/client2/backend.go b/cmd/client2/backend.go
index 64e9eae..21b4d88 100644
--- a/cmd/client2/backend.go
+++ b/cmd/client2/backend.go
@@ -28,6 +28,7 @@ func receiveHandler(connection *websocket.Conn, container *UIContainer) {
 		err := connection.ReadJSON(&resp)
 		if err != nil {
 			log.Println("Error in receive:", err)
+			break
 		}
 		switch resp.Result {
 		case coordinator.SessionRespJoined1:
@@ -55,7 +56,8 @@ func receiveHandler(connection *websocket.Conn, container *UIContainer) {
 			}
 		case coordinator.SessionRespLeft:
 			container.Output <- "game left"
-			break
+			matchID = uuid.Nil
+			return
 		case coordinator.SessionRespBroadcastSenTurn:
 			container.Output <- "Sentinal may take their turn"
 		case coordinator.SessionRespBroadcastScoTrun:
@@ -166,15 +168,20 @@ func backend(container *UIContainer) {
 			}
 			return
 		case <-ticker.C:
-			if matchID != uuid.Nil {
-				err := conn.WriteJSON(coordinator.SessionCommand{
-					ID:      id,
-					MatchID: matchID,
-					Command: coordinator.SessionCmdPoll,
-				})
-				if err != nil {
-					log.Println("Error writing to websocket:", err)
-					return
+			select {
+			case <-done:
+				return
+			default:
+				if matchID != uuid.Nil {
+					err := conn.WriteJSON(coordinator.SessionCommand{
+						ID:      id,
+						MatchID: matchID,
+						Command: coordinator.SessionCmdPoll,
+					})
+					if err != nil {
+						log.Println("Error writing to websocket:", err)
+						return
+					}
 				}
 			}
 		}
diff --git a/cmd/server/server.go b/cmd/server/server.go
index 749a780..fa87df2 100644
--- a/cmd/server/server.go
+++ b/cmd/server/server.go
@@ -3,6 +3,7 @@ package main
 import (
 	"log"
 	"net/http"
+	"time"
 
 	"git.saintnet.tech/stryan/snengame/internal/coordinator"
 	"github.com/gorilla/websocket"
@@ -53,6 +54,7 @@ func serveWs(c *coordinator.Coordinator, w http.ResponseWriter, r *http.Request)
 			break
 		}
 		if resp.Result == coordinator.SessionRespLeft {
+			time.Sleep(1 * time.Second) //give clients a second to respond
 			break
 		}
 	}
diff --git a/internal/coordinator/coordinator.go b/internal/coordinator/coordinator.go
index badb966..a46a1ee 100644
--- a/internal/coordinator/coordinator.go
+++ b/internal/coordinator/coordinator.go
@@ -122,6 +122,11 @@ func (c *Coordinator) Coordinate(cmd *SessionCommand) *SessionCommandResult {
 	case SessionCmdPoll:
 		m, exists := c.Matches[cmd.MatchID]
 		if exists {
+			_, exists = m.Broadcasts[cmd.ID]
+			if !exists {
+				log.Printf("%v has opted in to polling", cmd.ID)
+				m.Broadcasts[cmd.ID] = make(chan SessionResp, 10)
+			}
 			select {
 			case res := <-m.Broadcasts[cmd.ID]:
 				return &SessionCommandResult{
@@ -158,7 +163,7 @@ func MatchWatcher(m *Session) {
 	for {
 		select {
 		case <-ticker.C:
-			if m.Active && m.Game != nil {
+			if m.Active && m.Game != nil && len(m.Broadcasts) > 0 {
 				if m.Game.Status == game.StatusLobby && !sen_ready && m.Game.SentinalPlayer.Ready {
 					for _, v := range m.Broadcasts {
 						v <- SessionRespBroadcastSenReady
diff --git a/internal/coordinator/session.go b/internal/coordinator/session.go
index 9978f5f..b11250e 100644
--- a/internal/coordinator/session.go
+++ b/internal/coordinator/session.go
@@ -71,7 +71,6 @@ func (s *Session) Join(id uuid.UUID) SessionResp {
 		for _, v := range s.Broadcasts {
 			v <- SessionRespBroadcastSenJoin
 		}
-		s.Broadcasts[id] = make(chan SessionResp)
 		return SessionRespJoined1
 	} else if s.p2 == uuid.Nil {
 		s.p2 = id
@@ -79,7 +78,6 @@ func (s *Session) Join(id uuid.UUID) SessionResp {
 		for _, v := range s.Broadcasts {
 			v <- SessionRespBroadcastScoJoin
 		}
-		s.Broadcasts[id] = make(chan SessionResp)
 		return SessionRespJoined2
 	} else {
 		return SessionRespJoinError