diff --git a/src/game.rs b/src/game.rs
index ecc028c..9f78d58 100644
--- a/src/game.rs
+++ b/src/game.rs
@@ -7,14 +7,14 @@ pub struct Game {
 }
 
 impl Game {
-    pub fn move_player(&mut self, dx: i8, dy: i8) {
+    pub fn move_player(&mut self, dx: i16, dy: i16) {
         // check if move is allowed first
         let player = &self.player;
         let player_pos = player.get_position();
-        let mut level = &self.levels[player_pos.get_level() as usize];
-        let new_x = ((player_pos.get_x() as i16) + dx as i16) as u16;
-        let new_y = ((player_pos.get_y() as i16) + dy as i16) as u16;
-        let can_go: bool = match level.get_element(new_x as i16, new_y as i16) {
+        let level = &self.levels[player_pos.get_level()];
+        let new_x: i16 = player_pos.get_x() as i16 + dx;
+        let new_y: i16 = player_pos.get_y() as i16 + dy;
+        let can_go: bool = match level.get_element(new_x, new_y) {
             None => { false }
             Some(t) => {
                 match t {
@@ -24,20 +24,21 @@ impl Game {
             }
         };
         if can_go {
-            if level.get_element(new_x as i16, new_y as i16).unwrap() == LevelElement::StairDown {
-                let start_x = self.levels[(player_pos.get_level() + 1) as usize].start_x;
-                let start_y = self.levels[(player_pos.get_level() + 1) as usize].start_y;
-                self.player.set_position(player_pos.get_level() + 1, start_x as u16, start_y as u16);
-                self.levels[(player_pos.get_level() + 1) as usize].discover(start_x as i16, start_y as i16);
-            } else if level.get_element(new_x as i16, new_y as i16).unwrap() == LevelElement::StairUp {
+            if level.get_element(new_x, new_y).unwrap() == LevelElement::StairDown {
+                let next_level = player_pos.get_level() + 1;
+                let start_x: usize = self.levels[next_level].start_x;
+                let start_y: usize = self.levels[next_level].start_y;
+                self.player.set_position(next_level, start_x, start_y);
+                self.levels[next_level].discover(self.player.get_position());
+            } else if level.get_element(new_x, new_y).unwrap() == LevelElement::StairUp {
                 self.player.set_position(
                     player_pos.get_level() - 1,
-                    self.levels[(player_pos.get_level() - 1) as usize].end_x as u16,
-                    self.levels[(player_pos.get_level() - 1) as usize].end_y as u16,
+                    self.levels[player_pos.get_level() - 1].end_x,
+                    self.levels[player_pos.get_level() - 1].end_y,
                 );
             } else {
                 self.player.change_position(dx, dy);
-                self.levels[player_pos.get_level() as usize].discover(new_x as i16, new_y as i16);
+                self.levels[player_pos.get_level()].discover(self.player.get_position());
             }
         }
     }
diff --git a/src/level.rs b/src/level.rs
index 28ca1b2..6c62ddb 100644
--- a/src/level.rs
+++ b/src/level.rs
@@ -1,4 +1,5 @@
 use std::cmp::{max, min};
+use crate::position::Position;
 
 pub const LEVEL_WIDTH: usize = 50;
 pub const LEVEL_HEIGHT: usize = 25;
@@ -48,48 +49,46 @@ impl Level {
         if x < 0 || y < 0 {
             return None;
         }
-        if x >= LEVEL_WIDTH as i16 || y >= LEVEL_HEIGHT as i16 {
+        let x = x as usize;
+        let y = y as usize;
+        if x >= LEVEL_WIDTH || y >= LEVEL_HEIGHT {
             return None;
         }
-        if self.discovered[x as usize][y as usize] {
-            return Some(self.structure[x as usize][y as usize]);
+        if self.discovered[x][y] {
+            return Some(self.structure[x][y]);
         }
         return Some(LevelElement::Unknown);
     }
     /// discover the area with in the level around the given position
-    pub fn discover(&mut self, x: i16, y: i16) {
-        for x_r in x - 1..=x + 1 {
-            for y_r in y - 1..=y + 1 {
-                let tx = min(max(x_r, 0), (LEVEL_WIDTH - 1) as i16) as usize;
-                let ty = min(max(y_r, 0), (LEVEL_HEIGHT - 1) as i16) as usize;
-                self.discovered[tx][ty] = true;
+    pub fn discover(&mut self, pos: Position) {
+        let x = pos.get_x();
+        let y = pos.get_y();
+        for x_r in max(x - 1, 0)..=min(x + 1, LEVEL_WIDTH - 1) {
+            for y_r in max(y - 1, 0)..=min(y + 1, LEVEL_HEIGHT - 1) {
+                self.discovered[x_r][y_r] = true;
             }
         }
-        for x_r in x..=x + 2 {
-            let tx = min(max(x_r, 0), (LEVEL_WIDTH - 1) as i16) as usize;
-            self.discovered[tx][y as usize] = true;
-            if self.structure[tx][y as usize] == LevelElement::Wall {
+        for x_r in x..=min(x + 2, LEVEL_WIDTH - 1) {
+            self.discovered[x_r][y] = true;
+            if self.structure[x_r][y] == LevelElement::Wall {
                 break;
             }
         }
-        for y_r in y..=y + 2 {
-            let ty = min(max(y_r, 0), (LEVEL_HEIGHT - 1) as i16) as usize;
-            self.discovered[x as usize][ty] = true;
-            if self.structure[x as usize][ty] == LevelElement::Wall {
+        for y_r in y..=min(y + 2, LEVEL_WIDTH - 1) {
+            self.discovered[x][y_r] = true;
+            if self.structure[x][y_r] == LevelElement::Wall {
                 break;
             }
         }
-        for x_r in (x-2..x).rev() {
-            let tx = min(max(x_r, 0), (LEVEL_WIDTH - 1) as i16) as usize;
-            self.discovered[tx][y as usize] = true;
-            if self.structure[tx][y as usize] == LevelElement::Wall {
+        for x_r in (max(x - 2, 0)..x).rev() {
+            self.discovered[x_r][y] = true;
+            if self.structure[x_r][y] == LevelElement::Wall {
                 break;
             }
         }
-        for y_r in (y-2..y).rev() {
-            let ty = min(max(y_r, 0), (LEVEL_HEIGHT - 1) as i16) as usize;
-            self.discovered[x as usize][ty] = true;
-            if self.structure[x as usize][ty] == LevelElement::Wall {
+        for y_r in (max(y - 2, 0)..y).rev() {
+            self.discovered[x][y_r] = true;
+            if self.structure[x][y_r] == LevelElement::Wall {
                 break;
             }
         }
diff --git a/src/level_widget.rs b/src/level_widget.rs
index cd37bea..d9703e5 100644
--- a/src/level_widget.rs
+++ b/src/level_widget.rs
@@ -2,7 +2,7 @@ use ratatui::prelude::*;
 use ratatui::widgets::Widget;
 
 use crate::game::Game;
-use crate::level::LevelElement;
+use crate::level::{Level, LevelElement};
 
 const FG_BROWN: Color = Color::Rgb(186, 74, 0);
 
@@ -70,10 +70,10 @@ impl<'a> Widget for LevelWidget<'a> {
     fn render(self, area: Rect, buf: &mut Buffer) {
         let player = &self.game.player;
         let player_pos = player.get_position();
-        let level = &self.game.levels[player_pos.get_level() as usize];
+        let level: &Level = &self.game.levels[player_pos.get_level()];
 
-        let al = area.left();
-        let at = area.top();
+        let al: u16 = area.left();
+        let at: u16 = area.top();
 
         // draw the level elements
         for x in al..area.right() {
@@ -111,7 +111,9 @@ impl<'a> Widget for LevelWidget<'a> {
         }
 
         // draw player
-        self.set_cell(buf, al + player_pos.get_x(), at + player_pos.get_y(), "8", Color::Red, Color::Gray);
+        let player_x = al + player_pos.get_x() as u16;
+        let player_y = at + player_pos.get_y() as u16;
+        self.set_cell(buf, player_x, player_y, "8", Color::Red, Color::Gray);
     }
 }
 
diff --git a/src/main.rs b/src/main.rs
index 7fe0216..3084423 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -36,7 +36,7 @@ fn main() -> Result<()> {
         levels,
     };
 
-    g.move_player((levels[0].start_x) as i8, (levels[0].start_y) as i8);
+    g.move_player(levels[0].start_x as i16, levels[0].start_y as i16);
 
     stdout().execute(EnterAlternateScreen)?;
     enable_raw_mode()?;
@@ -89,6 +89,9 @@ fn main() -> Result<()> {
                 if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('q') {
                     break;
                 }
+                if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('d') {
+                    ;
+                }
                 if key.kind == KeyEventKind::Press && key.code == KeyCode::Left {
                     g.move_player(-1, 0);
                 }
diff --git a/src/player.rs b/src/player.rs
index a17cf5e..406a530 100644
--- a/src/player.rs
+++ b/src/player.rs
@@ -5,12 +5,12 @@ use crate::position::Position;
 pub struct Player {
     name: String,
     position: Position,
-    life: i16,
-    max_life: i16,
+    life: usize,
+    max_life: usize,
 }
 
 impl Player {
-    pub fn new(name: &str, max_life: i16) -> Player {
+    pub fn new(name: &str, max_life: usize) -> Player {
         Player {
             name: name.to_string(),
             position: Position::new(0, 0, 0),
@@ -21,19 +21,23 @@ impl Player {
     pub fn get_name(&self) -> String {
         return self.name.clone();
     }
-    pub fn get_life(&self) -> i16 { self.life }
-    pub fn get_max_life(&self) -> i16 { self.max_life }
+    pub fn get_life(&self) -> usize { self.life }
+    pub fn get_max_life(&self) -> usize { self.max_life }
     pub fn change_life(&mut self, by: i16) {
-        self.life = max(0, min(self.max_life, self.life + by));
+        self.life = max(0,
+                        min(self.max_life,
+                            (self.life as i16 + by) as usize,
+                        ),
+        );
     }
     pub fn get_position(&self) -> Position {
         self.position
     }
-    pub fn change_position(&mut self, dx: i8, dy: i8) {
+    pub fn change_position(&mut self, dx: i16, dy: i16) {
         self.position.change(dx, dy);
     }
 
-    pub fn set_position(&mut self, level: u8, x: u16, y:u16) {
+    pub fn set_position(&mut self, level: usize, x: usize, y: usize) {
         self.position.set(level, x, y);
     }
 }
diff --git a/src/position.rs b/src/position.rs
index 20e50ef..14d6a5c 100644
--- a/src/position.rs
+++ b/src/position.rs
@@ -1,35 +1,35 @@
 #[derive(Copy, Clone, Debug, PartialEq)]
 pub struct Position {
-    level: u8,
-    x: u16,
-    y: u16,
+    level: usize,
+    x: usize,
+    y: usize,
 }
 
 impl Position {
-    pub fn new(level: u8, x: u16, y: u16) -> Self {
+    pub fn new(level: usize, x: usize, y: usize) -> Self {
         Self {
             level,
             x,
             y,
         }
     }
-    pub fn get_level(&self) -> u8 {
+    pub fn get_level(&self) -> usize{
         self.level
     }
 
-    pub fn get_x(&self) -> u16 {
+    pub fn get_x(&self) -> usize {
         self.x
     }
 
-    pub fn get_y(&self) -> u16 {
+    pub fn get_y(&self) -> usize {
         self.y
     }
 
-    pub fn change(&mut self, dx: i8, dy: i8) {
-        self.x = ((self.x as i16) + dx as i16) as u16;
-        self.y = ((self.y as i16) + dy as i16) as u16;
+    pub fn change(&mut self, dx: i16, dy: i16) {
+        self.x = ((self.x as i16) + dx) as usize;
+        self.y = ((self.y as i16) + dy) as usize;
     }
-    pub fn set(&mut self, level: u8, x: u16, y:u16) {
+    pub fn set(&mut self, level: usize, x: usize, y:usize) {
         self.level = level;
         self.x = x;
         self.y = y;