From bc795f65c000699e7aa950e9e4943a91aac8017b Mon Sep 17 00:00:00 2001
From: roby2014 <roby2x14@gmail.com>
Date: Mon, 15 Jul 2024 18:59:04 +0100
Subject: [PATCH] docs: add network tcp sample

---
 core/samples/CMakeLists.txt   |  1 +
 core/samples/net/tcp/main.cpp | 67 +++++++++++++++++++++++++++++++++++
 core/samples/net/tcp/page.md  | 45 +++++++++++++++++++++++
 3 files changed, 113 insertions(+)
 create mode 100644 core/samples/net/tcp/main.cpp
 create mode 100644 core/samples/net/tcp/page.md

diff --git a/core/samples/CMakeLists.txt b/core/samples/CMakeLists.txt
index 12822c70e..ea794e2db 100644
--- a/core/samples/CMakeLists.txt
+++ b/core/samples/CMakeLists.txt
@@ -47,3 +47,4 @@ make_sample(DIR "ecs/events")
 make_sample(DIR "ecs/relations")
 make_sample(DIR "gl/compute")
 make_sample(DIR "gl/quad")
+make_sample(DIR "net/tcp")
diff --git a/core/samples/net/tcp/main.cpp b/core/samples/net/tcp/main.cpp
new file mode 100644
index 000000000..14b22b002
--- /dev/null
+++ b/core/samples/net/tcp/main.cpp
@@ -0,0 +1,67 @@
+#include <cstring>
+#include <iostream>
+#include <thread>
+
+#include <cubos/core/log.hpp>
+/// [Import headers]
+#include <cubos/core/net/tcp_listener.hpp>
+#include <cubos/core/net/tcp_stream.hpp>
+/// [Import headers]
+#include <cubos/core/reflection/external/cstring.hpp>
+#include <cubos/core/reflection/external/primitives.hpp>
+
+using cubos::core::net::Address;
+using cubos::core::net::TcpListener;
+using cubos::core::net::TcpStream;
+
+/// [Define constants]
+#define SERVER_ADDRESS Address::LocalHost
+#define SERVER_PORT 8080
+/// [Define constants]
+
+/// [Server function]
+void runServer()
+{
+    TcpListener listener;
+    listener.listen(SERVER_ADDRESS, SERVER_PORT, 1);
+
+    CUBOS_DEBUG("Server is listening");
+
+    TcpStream clientStream;
+    while (listener.accept(clientStream))
+    {
+        char buffer[1024];
+        if (std::size_t bytesRead = clientStream.read(buffer, sizeof(buffer)); bytesRead > 0)
+        {
+            CUBOS_INFO("Received message: {} with size {}", buffer, bytesRead);
+            break;
+        }
+    }
+
+    listener.close();
+}
+/// [Server function]
+
+/// [Client function]
+void runClient()
+{
+    TcpStream stream;
+    stream.connect(SERVER_ADDRESS, SERVER_PORT);
+
+    const char* message = "Hello Cubos!";
+    stream.write(message, std::strlen(message));
+    stream.disconnect();
+}
+/// [Client function]
+
+int main()
+{
+    std::thread serverThread(runServer);
+    std::this_thread::sleep_for(std::chrono::milliseconds(1000)); // wait so server is up
+    std::thread clientThread(runClient);
+
+    serverThread.join();
+    clientThread.join();
+
+    return 0;
+}
\ No newline at end of file
diff --git a/core/samples/net/tcp/page.md b/core/samples/net/tcp/page.md
new file mode 100644
index 000000000..763079a4c
--- /dev/null
+++ b/core/samples/net/tcp/page.md
@@ -0,0 +1,45 @@
+# Tcp Sockets {#examples-core-tcp-sockets}
+
+@brief Using TCP sockets for communication between a server and a client.
+
+@see Full source code [here](https://github.com/GameDevTecnico/cubos/tree/main/core/samples/net/tcp).
+
+This example demonstrates how to set up a TCP server and client, exchanging data, using the **Cubos** engine.
+
+The TCP sockets are wrapped around a @ref cubos::core::net::TcpListener and @ref cubos::core::net::TcpStream classes for a better API and simpler usage.
+
+First, we need the network dependencies:
+
+@snippet net/tcp/main.cpp Import headers
+
+We'll also define some dummy constants for demonstration purposes:
+
+@snippet net/tcp/main.cpp Define constants
+
+Now, let's launch the "TCP server", which will be a @ref cubos::core::net::TcpListener waiting for a new connection, and quit after receveing a message from client via @ref cubos::core::net::TcpStream .
+
+@snippet net/tcp/main.cpp Server function
+
+Server is up and waiting, so let's create the client which will send a message to the server.
+
+@snippet net/tcp/main.cpp Client function
+
+To finish off, let's launch them in separate threads, because we are using blocking methods (such as `accept`).
+
+@snippet net/tcp/main.cpp Main function
+
+Output:
+
+```
+[20:36:53.918] [tcp_listener.cpp:67 listen] info: TCP listener socket '3' at address "127.0.0.1" with port '8080'
+[20:36:53.919] [main.cpp:28 runServer] debug: Server is listening
+[20:36:54.918] [tcp_listener.cpp:80 accept] info: Connecting stream to socket
+[20:36:54.919] [tcp_stream.cpp:45 connect] info: New TCP stream at address "127.0.0.1" and port '8080'
+[20:36:54.919] [tcp_stream.cpp:54 inner] info: New TCP stream at socket 4
+[20:36:54.919] [tcp_stream.cpp:136 write] info: Sent TCP message
+[20:36:54.919] [tcp_stream.cpp:111 read] info: Incoming TCP message
+[20:36:54.920] [main.cpp:36 runServer] info: Received message: "Hello Cubos!" with size 12
+[20:36:54.920] [tcp_stream.cpp:62 disconnect] warn: Closing TCP stream socket: '5'
+[20:36:54.920] [tcp_listener.cpp:89 close] warn: Closing TCP listener socket: '3'
+[20:36:54.921] [tcp_stream.cpp:62 disconnect] warn: Closing TCP stream socket: '4'
+```
\ No newline at end of file