finished server main hopefully

src/main.rs

@@ -1,3 +1,103 @@
-fn main() {
-    println!("Hello, world!");
+use std::collections::HashMap;
+use std::sync::Arc;
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::{TcpListener, TcpStream};
+use tokio::sync::RwLock; // Use Tokio's async-aware lock
+
+// Type alias for our shared thread-safe state
+type Db = Arc<RwLock<HashMap<String, String>>>;
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Bind to all interfaces on port 5901
+    let listener = TcpListener::bind("0.0.0.0:5901").await?;
+    let db: Db = Arc::new(RwLock::new(HashMap::new()));
+
+    println!("🚀 Escape Room Server active on port 5901");
+    println!("Waiting for teams to connect...");
+
+    loop {
+        let (socket, _) = listener.accept().await?;
+        let db_clone = Arc::clone(&db);
+
+        // Spawn a new async task for every connection
+        tokio::spawn(async move {
+            if let Err(e) = handle_connection(socket, db_clone).await {
+                eprintln!("[SOCKET ERROR] {}", e);
+            }
+        });
+    }
 }
+
+async fn handle_connection(mut socket: TcpStream, db: Db) -> std::io::Result<()> {
+    let mut buf = [0; 1024];
+    let n = socket.read(&mut buf).await?;
+
+    // Connection closed
+    if n == 0 {
+        return Ok(());
+    }
+
+    let request = String::from_utf8_lossy(&buf[..n]);
+    let parts: Vec<&str> = request.trim().split_whitespace().collect();
+
+    if parts.is_empty() {
+        return Ok(());
+    }
+
+    match parts[0].to_uppercase().as_str() {
+        // Teams submit their solution: PUT [team_id] [value]
+        "PUT" => {
+            if parts.len() == 3 {
+                let team_id = parts[1].to_string();
+                let val = parts[2].to_string();
+
+                let mut data = db.write().await; // Async lock
+                data.insert(team_id.clone(), val.clone());
+
+                socket.write_all(b"ACK\n").await?;
+                println!("[LOG] Team {} submitted solution: {}", team_id, val);
+            }
+        }
+
+        // Teams request previous solution: GET [prev_team_id]
+        "GET" => {
+            if parts.len() == 2 {
+                let target_id = parts[1];
+                let data = db.read().await; // Async lock
+
+                let response = data
+                    .get(target_id)
+                    .cloned()
+                    .unwrap_or_else(|| "-1".to_string());
+
+                if response == "-1" {
+                    println!("[WAIT] Team requested {}, but no data yet.", target_id);
+                }
+
+                socket.write_all(response.as_bytes()).await?;
+            }
+        }
+
+        // Admin override: ADMIN SET [team_id] [value]
+        "ADMIN" => {
+            if parts.len() == 4 && parts[1].to_uppercase() == "SET" {
+                let team_id = parts[2].to_string();
+                let val = parts[3].to_string();
+
+                let mut data = db.write().await;
+                data.insert(team_id.clone(), val.clone());
+
+                socket.write_all(b"ADMIN_OK\n").await?;
+                println!("[ADMIN] Manual set: Team {} -> {}", team_id, val);
+            }
+        }
+
+        _ => {
+            socket.write_all(b"ERR_INVALID_CMD\n").await?;
+        }
+    }
+
+    Ok(())
+}
+