Add basic TCP.

src/tcp.rs

@@ -0,0 +1,60 @@
+use tokio::net::TcpListener;
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader, BufWriter};
+use tokio::sync::mpsc::Sender;
+
+use crate::signals::StartStopSignal;
+
+pub async fn tcp_command_server(tx: Sender<StartStopSignal>) {
+    let listener = TcpListener::bind("127.0.0.1:12345").await.unwrap();
+    println!("TCP command server listening on 12345");
+
+    loop {
+        let (socket, addr) = listener.accept().await.unwrap();
+        println!("Client connected: {:?}", addr);
+
+        let tx = tx.clone();
+
+        tokio::spawn(async move {
+            let (reader, writer) = socket.into_split();
+
+            let mut reader = BufReader::new(reader);
+            let mut writer = BufWriter::new(writer);
+            let mut lines = reader.lines();
+
+            while let Ok(Some(line)) = lines.next_line().await {
+                println!("Received: {}", line);
+
+                match parse_command(&line) {
+                    Some(signal) => {
+                        if tx.send(signal).await.is_ok() {
+                            let _ = writer.write_all(b"OK\n").await;
+                        } else {
+                            let _ = writer.write_all(b"ERR internal channel failure\n").await;
+                            break;
+                        }
+                    }
+                    None => {
+                        let _ = writer.write_all(b"ERR unknown command\n").await;
+                    }
+                }
+
+                let _ = writer.flush().await;
+            }
+
+            println!("Client disconnected: {:?}", addr);
+        });
+    }
+}
+
+fn parse_command(line: &str) -> Option<StartStopSignal> {
+    let parts: Vec<&str> = line.split_whitespace().collect();
+
+    match parts.as_slice() {
+        ["STOP"] => Some(StartStopSignal::Stop),
+
+        _ => {
+            eprintln!("Unknown command: {}", line);
+            None
+        }
+    }
+}