fix: Client sometimes get stuck in lobby

There was a previous fix attempt for this. The client still got stuck in
the lobby sometimes after the game has started. This was due to a race
between the state update handler and the login form handler. These both
relied on the gameStarted flag which has now been removed. Only the
state update handler can switch pages based on the update contents.

internal/client/application.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"log/slog"
 	"net"
-	"sync/atomic"
 	"time"
 
 	"github.com/gobwas/ws"
@@ -61,10 +60,9 @@ type Application struct {
 	stocks [4]int
 	prices [4]int
 
-	gameStarted atomic.Bool
-	server      network.Connection
-	errCh       chan string
-	l           *slog.Logger
+	server network.Connection
+	errCh  chan string
+	l      *slog.Logger
 }
 
 func NewApplication(l *slog.Logger) *Application {
@@ -109,11 +107,6 @@ func (a *Application) initUI() {
 			}
 			// Successful login.
 			a.lobby.Reset()
-			if a.gameStarted.Load() {
-				a.pages.SwitchToPage(gamePageName)
-			} else {
-				a.pages.SwitchToPage(lobbyPageName)
-			}
 		},
 		func() {
 			a.Stop()

internal/client/event_handlers.go

@@ -30,8 +30,7 @@ func (a *Application) handleStateUpdate(state *message.GameState) {
 
 	// Readiness update.
 	if !state.Started {
-		if a.gameStarted.Load() {
-			a.gameStarted.Store(false)
+		if page, _ := a.pages.GetFrontPage(); page == titlePageName || page == gamePageName {
 			a.pages.SwitchToPage(lobbyPageName)
 		}
 
@@ -41,9 +40,8 @@ func (a *Application) handleStateUpdate(state *message.GameState) {
 		return
 	}
 
-	// Switch to main page if game started.
-	if !a.gameStarted.Load() {
-		a.gameStarted.Store(true)
+	// Switch to game page if game started.
+	if page, _ := a.pages.GetFrontPage(); page == titlePageName || page == lobbyPageName {
 		a.pages.SwitchToPage(gamePageName)
 	}
 
@@ -53,7 +51,7 @@ func (a *Application) handleStateUpdate(state *message.GameState) {
 
 	// Update local game data.
 	if len(a.hand) == 0 || len(a.hand) != len(state.Player.Hand) {
-		// This is a little trick to only update the card list if the hand size did not change.
+		// This is a little trick to only update the actions display if the hand changed.
 		// It prevents the list from scrolling to the top on each update made by other players.
 		a.actions.Update(state.Player.Hand)
 	}