5 files changed, 163 insertions, 0 deletions

diff --git a/src/bin/server/args.rs b/src/bin/server/args.rs
new file mode 100644
index 0000000..31c0acc
--- /dev/null
+++ b/src/bin/server/args.rs
@@ -0,0 +1,41 @@
+pub struct Args {
+    pub ip: String,
+    pub port: u16,
+}
+
+pub fn parse_args() -> Args {
+    let args: Vec<String> = std::env::args().collect();
+    let mut ip = "127.0.0.1".to_string();
+    let mut port = 11525;
+    let mut i = 1;
+    while i < args.len() {
+        if args[i] == "-p" {
+            if i + 1 < args.len() {
+                port = args[i + 1].parse::<u16>().unwrap_or_else(|_| {
+                    eprintln!("Invalid port number: {}", args[i + 1]);
+                    std::process::exit(1);
+                });
+                i += 2;
+            } else {
+                eprintln!("-p requires a port number");
+                std::process::exit(1);
+            }
+        } else if args[i] == "-i" {
+            if i + 1 < args.len() {
+                ip = args[i + 1].clone();
+                if ip != "127.0.0.1" && ip != "0.0.0.0" {
+                    eprintln!("Invalid IP address: {}. Must be 127.0.0.1 or 0.0.0.0", ip);
+                    std::process::exit(1);
+                }
+                i += 2;
+            } else {
+                eprintln!("-i requires an IP address");
+                std::process::exit(1);
+            }
+        } else {
+            eprintln!("Unknown argument: {}", args[i]);
+            std::process::exit(1);
+        }
+    }
+    Args { ip, port }
+}
diff --git a/src/bin/server/database.rs b/src/bin/server/database.rs
new file mode 100644
index 0000000..9c51997
--- /dev/null
+++ b/src/bin/server/database.rs
@@ -0,0 +1,31 @@
+use rusqlite::Connection;
+
+pub fn init_db() -> Connection {
+    let conn = Connection::open("server.db").unwrap();
+    conn.execute(
+        "CREATE TABLE IF NOT EXISTS users (
+            username TEXT PRIMARY KEY,
+            hashed_password TEXT NOT NULL
+        )",
+        [],
+    ).unwrap();
+    conn
+}
+
+pub fn add_user(conn: &Connection, username: &str, hashed_password: &str) -> Result<(), Box<dyn std::error::Error>> {
+    conn.execute(
+        "INSERT INTO users (username, hashed_password) VALUES (?1, ?2)",
+        [username, hashed_password],
+    )?;
+    Ok(())
+}
+
+pub fn get_hashed_password(conn: &Connection, username: &str) -> Option<String> {
+    let mut stmt = conn.prepare("SELECT hashed_password FROM users WHERE username = ?1").unwrap();
+    let mut rows = stmt.query([username]).unwrap();
+    if let Ok(Some(row)) = rows.next() {
+        row.get(0).ok()
+    } else {
+        None
+    }
+}
diff --git a/src/bin/server/handler.rs b/src/bin/server/handler.rs
new file mode 100644
index 0000000..2132d09
--- /dev/null
+++ b/src/bin/server/handler.rs
@@ -0,0 +1,64 @@
+use std::io::{BufRead, BufReader, Write};
+use std::net::TcpStream;
+use std::sync::Mutex;
+use once_cell::sync::Lazy;
+use rusqlite::Connection;
+use crate::database;
+
+static DB_CONN: Lazy<Mutex<Connection>> = Lazy::new(|| Mutex::new(database::init_db()));
+
+pub fn handle_client(stream: TcpStream) {
+    let client_addr = stream.peer_addr().unwrap().to_string();
+    let mut user = "guest".to_string();
+    println!("[{} @ {}] Client connected", user, client_addr);
+    let reader_stream = stream.try_clone().unwrap();
+    let reader = BufReader::new(reader_stream);
+    let mut writer = stream;
+    for line in reader.lines() {
+        let line = line.unwrap();
+        println!("[{} @ {}] Received: {}", user, client_addr, line);
+        let response = process_message(&line, &mut user);
+        writeln!(writer, "{}", response).unwrap();
+    }
+    println!("[{} @ {}] Client disconnected", user, client_addr);
+}
+
+fn process_message(msg: &str, user: &mut String) -> String {
+    let parts: Vec<&str> = msg.splitn(3, ' ').collect();
+    match parts[0] {
+        "REGISTER" => {
+            if parts.len() != 3 {
+                "FAIL Invalid REGISTER format".to_string()
+            } else {
+                let username = parts[1];
+                let hashed_pass = parts[2];
+                let db = DB_CONN.lock().unwrap();
+                match database::add_user(&db, username, hashed_pass) {
+                    Ok(_) => format!("OK Registered {}", username),
+                    Err(_) => "FAIL User already exists".to_string(),
+                }
+            }
+        }
+        "AUTH" => {
+            if parts.len() != 3 {
+                "FAIL Invalid AUTH format".to_string()
+            } else {
+                let username = parts[1];
+                let provided_hash = parts[2];
+                let db = DB_CONN.lock().unwrap();
+                if let Some(stored_hash) = database::get_hashed_password(&db, username) {
+                    if provided_hash == stored_hash {
+                        *user = username.to_string();
+                        format!("OK {}", username)
+                    } else {
+                        "FAIL Invalid credentials".to_string()
+                    }
+                } else {
+                    "FAIL User not found".to_string()
+                }
+            }
+        }
+        "PING" => "PING".to_string(),
+        _ => msg.to_string(), // Echo back for compatibility
+    }
+}
diff --git a/src/bin/server/main.rs b/src/bin/server/main.rs
new file mode 100644
index 0000000..7693069
--- /dev/null
+++ b/src/bin/server/main.rs
@@ -0,0 +1,24 @@
+mod args;
+mod handler;
+mod database;
+
+use std::net::TcpListener;
+use std::thread;
+
+fn main() {
+    let args = args::parse_args();
+    let listener = match TcpListener::bind(format!("{}:{}", args.ip, args.port)) {
+        Ok(l) => l,
+        Err(e) => {
+            eprintln!("Failed to bind to {}:{}: {}", args.ip, args.port, e);
+            std::process::exit(1);
+        }
+    };
+    println!("Server listening on {}", listener.local_addr().unwrap());
+    for stream in listener.incoming() {
+        let stream = stream.unwrap();
+        thread::spawn(move || {
+            handler::handle_client(stream);
+        });
+    }
+}
diff --git a/src/bin/server/mod.rs b/src/bin/server/mod.rs
new file mode 100644
index 0000000..b2d622e
--- /dev/null
+++ b/src/bin/server/mod.rs
@@ -0,0 +1,3 @@
+pub mod args;
+pub mod handler;
+pub mod database;