1 files changed, 20 insertions, 5 deletions
diff --git a/src/input.rs b/src/input.rs
index 0db7e16..1258ac0 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -1,20 +1,35 @@
 use std::{io, time::Duration};
 use crossterm::{event::{self, KeyCode, KeyEvent}};
 
-pub fn handle_input(cursor: &mut usize, data: &mut [u8]) -> io::Result<bool> {
+pub fn handle_input(
+    cursor: &mut usize,
+    data: &mut [u8],
+    scroll_position: &mut usize
+) -> io::Result<bool> {
     if event::poll(Duration::from_millis(100))? {
         if let event::Event::Key(KeyEvent { code, .. }) = event::read()? {
             match code {
                 KeyCode::Esc => return Ok(false),
                 KeyCode::Left if *cursor > 0 => *cursor -= 1,
                 KeyCode::Right if *cursor < data.len() * 2 - 1 => *cursor += 1,
-                KeyCode::Up if *cursor >= 32 => *cursor -= 32,
-                KeyCode::Down if *cursor + 32 < data.len() * 2 => *cursor += 32,
+                KeyCode::Up => {
+                    if *cursor >= 32 {
+                        *cursor -= 32;
+                        *scroll_position = scroll_position.saturating_sub(1);
+                    }
+                },
+                KeyCode::Down => {
+                    if *cursor + 32 < data.len() * 2 {
+                        *cursor += 32;
+                        *scroll_position = scroll_position.saturating_add(1); 
+                    }
+                },
                 KeyCode::Char(c) if c.is_ascii_hexdigit() => {
                     let byte_index = *cursor / 2;
                     let shift = if *cursor % 2 == 0 { 4 } else { 0 };
-                    data[byte_index] = (data[byte_index] & (0x0F << (4 - shift))) | (c.to_digit(16).unwrap() as u8) << shift;
-                }
+                    data[byte_index] = (data[byte_index] & (0x0f << (4 - shift)))
+                        | (c.to_digit(16).unwrap() as u8) << shift;
+                },
                 _ => {}
             }
         }