fix diagonals and user input

src/agent.rs

@@ -1,4 +1,6 @@
 use crate::{board::Board, piece::Piece};
+use std::io;
+use std::io::prelude::*;
 
 pub trait Agent {
     fn next_move(&mut self, board: &Board) -> Option<(usize, usize)>;
@@ -12,7 +14,23 @@ pub struct ManualAgent {
 
 impl Agent for ManualAgent {
     fn next_move(&mut self, _: &Board) -> Option<(usize, usize)> {
-        todo!("user input not implemented")
+        let stdin = io::stdin();
+        let mut input = String::new();
+        let mut got: Option<(usize, usize)> = None;
+        while got.is_none() {
+            input.clear();
+            stdin.lock().read_line(&mut input).ok()?;
+            let numbers = input
+                .split_whitespace()
+                .map(|i| usize::from_str_radix(i, 10).ok())
+                .collect::<Option<Vec<usize>>>();
+            if let Some(numbers) = numbers {
+                if numbers.len() == 2 {
+                    got = Some((numbers[0], numbers[1]));
+                }
+            }
+        }
+        got
     }
 
     fn name(&self) -> &'static str {
@@ -23,3 +41,9 @@ impl Agent for ManualAgent {
         self.color
     }
 }
+
+impl ManualAgent {
+    pub const fn new(color: Piece) -> Self {
+        Self { color }
+    }
+}