feat(lobby): implement bounded WebSocket sessions and countdown

components/maze32_web/include/maze32_gateway.h

@@ -0,0 +1,57 @@
+#ifndef MAZE32_GATEWAY_H
+#define MAZE32_GATEWAY_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "esp_err.h"
+#include "esp_http_server.h"
+#include "esp_timer.h"
+#include "maze32_lobby.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define MAZE32_GATEWAY_CONNECTION_LIMIT MAZE32_SESSION_LIMIT
+#define MAZE32_GATEWAY_QUEUE_LIMIT 12U
+#define MAZE32_GATEWAY_OUTGOING_LIMIT 768U
+#define MAZE32_GATEWAY_RATE_LIMIT_PER_SECOND 20U
+
+typedef struct {
+    int active;
+    int socket_fd;
+    uint32_t last_client_sequence;
+    uint64_t rate_window_started_ms;
+    unsigned int messages_in_window;
+} maze32_gateway_connection_t;
+
+typedef struct {
+    int socket_fd;
+    size_t length;
+    char payload[MAZE32_GATEWAY_OUTGOING_LIMIT];
+} maze32_gateway_outgoing_t;
+
+typedef struct {
+    httpd_handle_t server;
+    maze32_lobby_t lobby;
+    maze32_gateway_connection_t connections[MAZE32_GATEWAY_CONNECTION_LIMIT];
+    maze32_gateway_outgoing_t outgoing[MAZE32_GATEWAY_QUEUE_LIMIT];
+    size_t outgoing_head;
+    size_t outgoing_count;
+    uint32_t server_sequence;
+    unsigned int suggestion_index;
+    esp_timer_handle_t countdown_timer;
+} maze32_gateway_t;
+
+esp_err_t maze32_gateway_init(maze32_gateway_t* gateway);
+void maze32_gateway_set_server(maze32_gateway_t* gateway, httpd_handle_t server);
+esp_err_t maze32_gateway_register(httpd_handle_t server, maze32_gateway_t* gateway);
+void maze32_gateway_close_socket(httpd_handle_t server, int socket_fd);
+int maze32_gateway_can_reconfigure(const maze32_gateway_t* gateway);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

components/maze32_web/include/maze32_web.h

@@ -3,13 +3,15 @@
 
 #include "esp_err.h"
 #include "esp_http_server.h"
+#include "maze32_gateway.h"
 #include "maze32_health.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-esp_err_t maze32_web_start(httpd_handle_t *server, maze32_health_t *health);
+esp_err_t maze32_web_start(httpd_handle_t* server, maze32_health_t* health,
+                           maze32_gateway_t* gateway);
 
 #ifdef __cplusplus
 }