make chest's gold depend on level

Cargo.lock

@@ -38,6 +38,12 @@ version = "2.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "327762f6e5a765692301e5bb513e0d9fef63be86bbc14528052b1cd3e6f03e07"
 
+[[package]]
+name = "bumpalo"
+version = "3.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f30e7476521f6f8af1a1c4c0b8cc94f0bee37d91763d0ca2665f299b6cd8aec"
+
 [[package]]
 name = "cassowary"
 version = "0.3.0"
@@ -86,7 +92,33 @@ name = "el_diabolo"
 version = "0.1.0"
 dependencies = [
  "crossterm",
+ "petgraph",
+ "rand",
  "ratatui",
+ "whoami",
+]
+
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
+[[package]]
+name = "fixedbitset"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
+
+[[package]]
+name = "getrandom"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe9006bed769170c11f845cf00c7c1e9092aeb3f268e007c3e760ac68008070f"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
 ]
 
 [[package]]
@@ -105,6 +137,16 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 
+[[package]]
+name = "indexmap"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d530e1a18b1cb4c484e6e34556a0d948706958449fca0cab753d649f2bce3d1f"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "indoc"
 version = "2.0.4"
@@ -120,6 +162,15 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "js-sys"
+version = "0.3.66"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cee9c64da59eae3b50095c18d3e74f8b73c0b86d2792824ff01bbce68ba229ca"
+dependencies = [
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.149"
@@ -198,6 +249,22 @@ version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "de3145af08024dea9fa9914f381a17b8fc6034dfb00f3a84013f7ff43f29ed4c"
 
+[[package]]
+name = "petgraph"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e1d3afd2628e69da2be385eb6f2fd57c8ac7977ceeff6dc166ff1657b0e386a9"
+dependencies = [
+ "fixedbitset",
+ "indexmap",
+]
+
+[[package]]
+name = "ppv-lite86"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.69"
@@ -216,6 +283,36 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
+]
+
 [[package]]
 name = "ratatui"
 version = "0.24.0"
@@ -354,6 +451,80 @@ version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "wasm-bindgen"
+version = "0.2.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ed0d4f68a3015cc185aff4db9506a015f4b96f95303897bfa23f846db54064e"
+dependencies = [
+ "cfg-if",
+ "wasm-bindgen-macro",
+]
+
+[[package]]
+name = "wasm-bindgen-backend"
+version = "0.2.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b56f625e64f3a1084ded111c4d5f477df9f8c92df113852fa5a374dbda78826"
+dependencies = [
+ "bumpalo",
+ "log",
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "syn",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-macro"
+version = "0.2.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0162dbf37223cd2afce98f3d0785506dcb8d266223983e4b5b525859e6e182b2"
+dependencies = [
+ "quote",
+ "wasm-bindgen-macro-support",
+]
+
+[[package]]
+name = "wasm-bindgen-macro-support"
+version = "0.2.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0eb82fcb7930ae6219a7ecfd55b217f5f0893484b7a13022ebb2b2bf20b5283"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-shared"
+version = "0.2.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ab9b36309365056cd639da3134bf87fa8f3d86008abf99e612384a6eecd459f"
+
+[[package]]
+name = "web-sys"
+version = "0.3.66"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50c24a44ec86bb68fbecd1b3efed7e85ea5621b39b35ef2766b66cd984f8010f"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "whoami"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22fc3756b8a9133049b26c7f61ab35416c130e8c09b660f5b3958b446f52cc50"
+dependencies = [
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "winapi"
 version = "0.3.9"

Cargo.toml

@@ -8,3 +8,6 @@ edition = "2021"
 [dependencies]
 ratatui = "0.24.0"
 crossterm = "0.27.0"
+rand = "0.8.5"
+petgraph = "0.6.4"
+whoami = "1.4.1"

src/artifacts.rs

@@ -1,12 +1,17 @@
-use crate::position::Position;
+use ratatui::style::Color;
+
 use crate::player::Player;
+use crate::position::Position;
 
 pub trait Artifact {
     //! An artifact that can be collected by the player
+    fn get_representation(&self) -> (&str, Color);
     /// get the position of the artifact in the level
     fn get_immutable_position(&self) -> &Position;
     /// call to apply the effects of the artifact to the player
     fn collect(&mut self, player: &mut Player);
+    /// returns if the artifact was collected and can be removed from the level
+    fn was_collected(&self) -> bool;
 }
 
 pub struct Chest {
@@ -17,19 +22,29 @@ pub struct Chest {
 
 impl Chest {
     pub fn new(position: Position) -> Self {
+        let level = position.get_level();
         Self {
             position,
-            gold: 10,
+            // TODO maybe randomize this?
+            gold: (level + 1) * 10,
         }
     }
 }
 
 impl Artifact for Chest {
+    fn get_representation(&self) -> (&str, Color) {
+        ("C", Color::Blue)
+    }
+
     fn get_immutable_position(&self) -> &Position { &self.position }
     fn collect(&mut self, player: &mut Player) {
         player.retrieve_gold(self.gold);
         self.gold = 0;
     }
+
+    fn was_collected(&self) -> bool {
+        self.gold == 0
+    }
 }
 
 pub struct Potion {
@@ -48,9 +63,16 @@ impl Potion {
 }
 
 impl Artifact for Potion {
+    fn get_representation(&self) -> (&str, Color) {
+        ("P", Color::Green)
+    }
     fn get_immutable_position(&self) -> &Position { &self.position }
     fn collect(&mut self, player: &mut Player) {
         player.change_life(self.health.try_into().unwrap());
         self.health = 0;
     }
+
+    fn was_collected(&self) -> bool {
+        self.health == 0
+    }
 }

src/game.rs

@@ -1,23 +1,228 @@
-use crate::level::Level;
+use crate::level::{Level, StructureElement};
+use crate::level_generator::LevelGenerator;
 use crate::player::Player;
+use crate::position::Position;
 
-pub const LEVELS: usize = 2;
+pub const LEVELS: usize = 10;
 
-pub struct Game<'game> {
+#[derive(PartialEq)]
-    pub player: &'game mut Player,
+/// represents a state of a game
-    pub levels: Vec<Level>,
+pub enum GameState {
+    /// the game is ongoing (neither won or lost)
+    RUNNING,
+    /// the player died
+    LOST,
+    /// the player reached the Ω
+    WON,
 }
 
-impl Game<'_> {
+
-    pub fn new(p: &mut Player) -> Game {
+/// the main structure to hold all information about the ongoing game
+pub struct Game {
+    /// the player
+    player: Player,
+    /// the levels of the game
+    levels: Vec<Level>,
+}
+
+impl Game {
+    pub fn new(p: Player) -> Game {
         let mut v: Vec<Level> = Vec::with_capacity(LEVELS);
         for d in 0..LEVELS {
-            let l = Level::new(d);
+            v.push(LevelGenerator::generate(d, d == 0, d == LEVELS - 1).render());
-            v.push(l);
         }
-        Game {
+        let mut g = Game {
             player: p,
             levels: v,
+        };
+        let start = {
+            g.get_level(0).start
+        };
+        g.get_mutable_player().get_position().set(0, start.0, start.1);
+        g.get_mutable_level(0).discover(&Position::new(0, start.0, start.1));
+        g
+    }
+
+    /// returns true if the player is dead (life <= 0)
+    fn player_is_dead(&self) -> bool { self.get_player().get_life() <= 0 }
+    /// returns true if the player is standing on the End element
+    fn player_reached_goal(&mut self) -> bool {
+        match self.next_element(0, 0) {
+            None => {}
+            Some(a) => {
+                match a {
+                    StructureElement::End => { return true; }
+                    _ => {}
+                }
+            }
+        };
+        false
+    }
+    /// returns the state of the game (depending on player's life and position)
+    pub fn get_game_state(&mut self) -> GameState {
+        if self.player_is_dead() {
+            return GameState::LOST;
+        }
+        if self.player_reached_goal() {
+            return GameState::WON;
+        }
+        GameState::RUNNING
+    }
+    pub fn get_player(&self) -> &Player {
+        &self.player
+    }
+    pub fn get_mutable_player(&mut self) -> &mut Player {
+        &mut self.player
+    }
+    pub fn get_level(&self, level: usize) -> &Level { &self.levels[level] }
+    pub fn get_mutable_level(&mut self, level: usize) -> &mut Level { &mut self.levels[level] }
+    /// check if the player can move in the given direction. This only checks for structure element
+    /// limitation as walls.
+    fn can_move(&mut self, dx: i16, dy: i16) -> bool {
+        let player_pos = &self.player.get_position();
+        let new_x: i16 = player_pos.get_x() as i16 + dx;
+        let new_y: i16 = player_pos.get_y() as i16 + dy;
+        let level = &mut self.levels[player_pos.get_level()];
+        match level.get_element(new_x, new_y) {
+            (None, _, _) => { return false; }
+            (Some(t), _, _) => {
+                match t {
+                    StructureElement::Wall => { return false; }
+                    _ => {}
+                }
+            }
+        };
+        true
+    }
+    /// returns the position (as tuple) of the next level's start point.
+    fn next_start(&self) -> (usize, usize, usize) {
+        let level = self.player.get_immutable_position().get_level() + 1;
+        let (x, y) = self.levels[level].start;
+        (level, x, y)
+    }
+    /// returns the position (as tuple) of the previous level's end point.
+    fn prev_end(&self) -> (usize, usize, usize) {
+        let level = self.player.get_immutable_position().get_level() - 1;
+        let (x, y) = self.levels[level].end;
+        (level, x, y)
+    }
+    /// get the next structure element sen from the player's position into the given direction.
+    fn next_element(&mut self, dx: i16, dy: i16) -> Option<StructureElement> {
+        let player_pos = &self.player.get_position();
+        let new_x: i16 = player_pos.get_x() as i16 + dx;
+        let new_y: i16 = player_pos.get_y() as i16 + dy;
+        let player_level = player_pos.get_level();
+        let level = &mut self.levels[player_level];
+        level.get_element(new_x, new_y).0
+    }
+
+    /// move the game's player into the given direction. If on the target field there is a stair,
+    /// the player follows the stair up/down to the next level.
+    /// Discovery is performed on the new location of the player.
+    /// The returned value is the direction that will bring the player back to his original field.
+    pub fn move_player(&mut self, mut dx: i16, mut dy: i16) -> (i16, i16) {
+        // verify the player can do the move
+        if !self.can_move(dx, dy) {
+            return (-dx, -dy);
+        }
+
+        let player_pos = &self.player.get_position();
+        let mut player_level = player_pos.get_level();
+        let structure = self.next_element(dx, dy);
+
+        // use stairs if walked onto one
+        match structure {
+            Some(e) => {
+                match e {
+                    StructureElement::StairDown => {
+                        (dx, dy) = (0, 0);
+                        let (next_level, x, y) = self.next_start();
+                        player_level = next_level;
+                        self.get_mutable_player().get_position().set(next_level, x, y);
+                    }
+                    StructureElement::StairUp => {
+                        (dx, dy) = (0, 0);
+                        let (next_level, x, y) = self.prev_end();
+                        player_level = next_level;
+                        self.get_mutable_player().get_position().set(next_level, x, y);
+                    }
+                    _ => {}
+                }
+            }
+            _ => {}
+        }
+
+        // update position and discover area on new position
+        let (new_x, new_y) = self.get_mutable_player().get_position().change(dx, dy);
+        self.get_mutable_level(player_level).discover(&Position::new(player_level, new_x, new_y));
+        (-dx, -dy)
+    }
+    pub fn player_fights_monster(&mut self) -> bool {
+        let player_pos = &self.player.get_immutable_position();
+        let player_level = player_pos.get_level();
+        let level = &mut self.levels[player_level];
+        let (_, m, _) = level.get_element(player_pos.get_x() as i16, player_pos.get_y() as i16);
+        match m {
+            None => {}
+            Some(m) => {
+                // TODO fight the monster
+                self.player.change_life(-1);
+                m.decrease_life(1);
+                return m.is_dead();
+            }
+        };
+        true
+    }
+    pub fn player_collects_artifact(&mut self) {
+        let player_pos = &self.player.get_immutable_position();
+        let player_level = player_pos.get_level();
+        let level = &mut self.levels[player_level];
+        let (_, _, a) = level.get_element(player_pos.get_x() as i16, player_pos.get_y() as i16);
+        match a {
+            None => {}
+            Some(a) => {
+                a.collect(&mut self.player);
             }
         }
     }
+    /// updates the player's current level. This will remove collected artifacts and dead monsters.
+    pub fn update_level(&mut self) {
+        let player_pos = &self.player.get_immutable_position();
+        let player_level = player_pos.get_level();
+        let level = &mut self.levels[player_level];
+        level.update();
+    }
+}
+
+#[test]
+fn game_has_correct_number_of_levels() {
+    let p = Player::new("foo", 42);
+    let g = Game::new(p);
+    assert_eq!(g.levels.len(), LEVELS);
+}
+
+#[test]
+fn game_has_player() {
+    let p = Player::new("foo", 42);
+    let g = Game::new(p);
+    assert_eq!(g.get_player().get_name(), "foo");
+    assert_eq!(g.get_player().get_immutable_position().get_level(), 0);
+}
+
+#[test]
+fn game_has_mutable_player() {
+    let p = Player::new("foo", 42);
+    let mut g = Game::new(p);
+    assert_eq!(g.get_player().get_name(), "foo");
+    g.get_mutable_player().change_life(-1);
+    assert_eq!(g.get_player().get_life(), 41);
+}
+
+#[test]
+fn game_get_level() {
+    let p = Player::new("foo", 42);
+    let mut g = Game::new(p);
+    g.get_level(0);
+    assert_ne!(g.get_level(0).start, (0, 0));
+    g.get_mutable_level(0).discover(&Position::new(0, 1, 1));
+}

src/level.rs

@@ -1,6 +1,11 @@
 use std::cmp::{max, min};
-use crate::artifacts::{Artifact, Chest, Potion};
+
+#[cfg(test)]
+use crate::artifacts::{Chest, Potion};
+use crate::artifacts::Artifact;
 use crate::monster::Monster;
+#[cfg(test)]
+use crate::monster::Rat;
 use crate::position::Position;
 
 pub const LEVEL_WIDTH: usize = 50;
@@ -8,6 +13,8 @@ pub const LEVEL_HEIGHT: usize = 25;
 
 #[derive(Copy, Clone, Debug, PartialEq)]
 pub enum StructureElement {
+    Start,
+    End,
     Wall,
     Floor,
     StairDown,
@@ -16,14 +23,19 @@ pub enum StructureElement {
 }
 
 pub struct Level {
-    level: usize,
+    pub(crate) level: usize,
-    structure: [[StructureElement; LEVEL_HEIGHT]; LEVEL_WIDTH],
+    pub(crate) structure: [[StructureElement; LEVEL_HEIGHT]; LEVEL_WIDTH],
-    discovered: [[bool; LEVEL_HEIGHT]; LEVEL_WIDTH],
+    pub(crate) discovered: [[bool; LEVEL_HEIGHT]; LEVEL_WIDTH],
-    monsters: Vec<Monster>,
+    pub(crate) monsters: Vec<Box<dyn Monster>>,
-    artifacts: Vec<Box<dyn Artifact>>,
+    pub(crate) artifacts: Vec<Box<dyn Artifact>>,
+    /// the position of the start in the level (either stair up or start point)
+    pub(crate) start: (usize, usize),
+    /// the position of the end in the level (either stair down or end point)
+    pub(crate) end: (usize, usize),
 }
 
 impl Level {
+    #[cfg(test)]
     pub fn new(level: usize) -> Level {
         let mut s = [[StructureElement::Wall; LEVEL_HEIGHT]; LEVEL_WIDTH];
         for x in 2..LEVEL_WIDTH - 2 {
@@ -37,9 +49,11 @@ impl Level {
             discovered: [[false; LEVEL_HEIGHT]; LEVEL_WIDTH],
             monsters: Vec::with_capacity(10),
             artifacts: Vec::with_capacity(10),
+            start: (0, 0),
+            end: (0, 0),
         }
     }
-    pub fn get_element(&mut self, x: i16, y: i16) -> (Option<StructureElement>, Option<&mut Monster>, Option<&mut Box<(dyn Artifact + 'static)>>) {
+    pub fn get_element(&mut self, x: i16, y: i16) -> (Option<StructureElement>, Option<&mut Box<(dyn Monster + 'static)>>, Option<&mut Box<(dyn Artifact + 'static)>>) {
         if x < 0 || y < 0 {
             return (None, None, None);
         }
@@ -52,7 +66,7 @@ impl Level {
             return (Some(StructureElement::Unknown), None, None);
         }
         let search_pos = &Position::new(self.level, x, y);
-        let mut res_m: Option<&mut Monster> = None;
+        let mut res_m: Option<&mut Box<dyn Monster>> = None;
         for m in &mut self.monsters {
             if m.get_immutable_position() == search_pos {
                 res_m = Some(m);
@@ -66,7 +80,8 @@ impl Level {
         }
         (Some(self.structure[x][y]), res_m, res_a)
     }
-    pub fn add_monster(&mut self, mut monster: Monster) -> Result<(), String> {
+    #[cfg(test)]
+    pub fn add_monster(&mut self, mut monster: impl Monster + 'static) -> Result<(), String> {
         if self.level != monster.get_position().get_level() {
             return Err("Wrong Level".to_string());
         }
@@ -75,25 +90,11 @@ impl Level {
                 return Err("Position already used".to_string());
             }
         }
-        self.monsters.push(monster);
+        self.monsters.push(Box::new(monster));
         Ok(())
     }
 
-    pub fn remove_dead_monster(&mut self, position: &Position) -> Result<(), String> {
+    #[cfg(test)]
-        if self.level != position.get_level() {
-            return Err("Wrong Level".to_string());
-        }
-        for (index, m) in &mut self.monsters.iter().enumerate() {
-            if m.get_immutable_position() == position {
-                if !m.is_dead() {
-                    return Err("Monster not dead".to_string());
-                }
-                self.monsters.remove(index);
-                break;
-            }
-        }
-        Ok(())
-    }
     pub fn add_artifact(&mut self, artifact: impl Artifact + 'static) -> Result<(), String> {
         if self.level != artifact.get_immutable_position().get_level() {
             return Err("Wrong Level".to_string());
@@ -106,18 +107,6 @@ impl Level {
         self.artifacts.push(Box::new(artifact));
         Ok(())
     }
-    pub fn remove_artifact(&mut self, position: &Position) -> Result<(), String> {
-        if self.level != position.get_level() {
-            return Err("Wrong Level".to_string());
-        }
-        for (index, a) in &mut self.artifacts.iter().enumerate() {
-            if a.get_immutable_position() == position {
-                self.monsters.remove(index);
-                break;
-            }
-        }
-        Ok(())
-    }
     /// discover the area with in the level around the given position
     pub fn discover(&mut self, pos: &Position) {
         let x = pos.get_x();
@@ -162,6 +151,21 @@ impl Level {
             }
         }
     }
+
+    pub fn update(&mut self) {
+        for (index, a) in &mut self.artifacts.iter().enumerate() {
+            if a.was_collected() {
+                self.artifacts.remove(index);
+                break;
+            }
+        }
+        for (index, m) in &mut self.monsters.iter().enumerate() {
+            if m.is_dead() {
+                self.monsters.remove(index);
+                break;
+            }
+        }
+    }
 }
 
 #[test]
@@ -189,19 +193,19 @@ fn test_discover_get_element() {
 #[test]
 fn test_discover_can_add_monster() {
     let mut l = Level::new(0);
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     m.get_position().set(1, 2, 3);
     assert_eq!(l.add_monster(m), Err("Wrong Level".to_string()));
 
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     m.get_position().set(0, 2, 3);
     assert_eq!(l.add_monster(m), Ok(()));
 
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     m.get_position().set(0, 2, 3);
     assert_eq!(l.add_monster(m), Err("Position already used".to_string()));
 
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     m.get_position().set(0, 2, 4);
     assert_eq!(l.add_monster(m), Ok(()));
 }
@@ -230,7 +234,7 @@ fn test_discover_get_monster() {
     assert_eq!(l.get_element(10, 10).0.unwrap(), StructureElement::Floor);
     assert!(l.get_element(10, 10).1.is_none());
 
-    let mut m = Monster::new(23);
+    let mut m = Rat::new(23);
     m.get_position().set(0, 10, 10);
     assert_eq!(l.add_monster(m), Ok(()));
 
@@ -266,7 +270,7 @@ fn test_discover_get_monster_can_move() {
     let p = Position::new(0, 10, 10);
     l.discover(&p);
 
-    let mut m = Monster::new(23);
+    let mut m = Rat::new(23);
     m.get_position().set(0, 10, 10);
     l.add_monster(m).expect("Panic because of");
 
@@ -279,20 +283,3 @@ fn test_discover_get_monster_can_move() {
     assert!(m.is_some());
     assert_eq!(m.unwrap().get_life(), 23);
 }
-
-#[test]
-fn test_monster_can_be_removed() {
-    let mut level = Level::new(0);
-    level.discover(&Position::new(0, 10, 10));
-
-    let mut m = Monster::new(2);
-    m.get_position().set(0, 10, 10);
-    level.add_monster(m).expect("Panic because of");
-
-    let m = level.get_element(10, 10).1.unwrap();
-    m.decrease_life(3);
-
-    assert_eq!(level.remove_dead_monster(&Position::new(0, 10, 10)), Ok(()));
-
-    assert!(level.get_element(10, 10).1.is_none());
-}

src/level_generator.rs

@@ -0,0 +1,360 @@
+use std::cmp::{max, min};
+use std::ops::Range;
+
+use petgraph::algo::min_spanning_tree;
+use petgraph::data::*;
+use petgraph::graph::Graph;
+use petgraph::graph::UnGraph;
+use rand::prelude::SliceRandom;
+use rand::Rng;
+use rand::rngs::ThreadRng;
+
+use crate::artifacts::{Artifact, Chest, Potion};
+use crate::level::{Level, StructureElement};
+use crate::monster::{Monster, Orc, Rat};
+use crate::position::Position;
+
+const ROOMS_VERTICAL: usize = 7;
+const ROOMS_HORIZONTAL: usize = 4;
+
+const ROOM_WIDTH: usize = 7;
+const ROOM_HEIGHT: usize = 6;
+
+#[derive(PartialEq, Copy, Clone)]
+enum RoomType {
+    Start,
+    End,
+    StairUp,
+    StairDown,
+    BasicRoom,
+    TreasureRoom,
+    MonsterRoom,
+    EmptyRoom,
+}
+
+#[derive(Copy, Clone)]
+struct ConnectionInfo {
+    offset: usize,
+    distance: usize,
+}
+
+#[derive(Copy, Clone)]
+struct Room {
+    pub kind: RoomType,
+    pub offset_x: usize,
+    pub offset_y: usize,
+    pub width: usize,
+    pub height: usize,
+    pub connection_down: Option<ConnectionInfo>,
+    pub connection_right: Option<ConnectionInfo>,
+}
+
+impl Room {
+    fn new() -> Self {
+        Self {
+            kind: RoomType::EmptyRoom,
+            offset_x: 0,
+            offset_y: 0,
+            width: 0,
+            height: 0,
+            connection_down: None,
+            connection_right: None,
+        }
+    }
+    /// change the size and position of a room randomly within its bounds
+    fn random(&mut self, rng: &mut ThreadRng) {
+        let width = rng.gen_range(3..6);
+        let height = rng.gen_range(3..5);
+        self.width = width;
+        self.height = height;
+        self.offset_x = rng.gen_range(0..(ROOM_WIDTH - width));
+        self.offset_y = rng.gen_range(0..(ROOM_HEIGHT - height));
+    }
+    fn get_x_range(&self) -> Range<usize> {
+        self.offset_x..self.offset_x + self.width
+    }
+    fn get_y_range(&self) -> Range<usize> {
+        self.offset_y..self.offset_y + self.height
+    }
+}
+
+pub struct LevelGenerator {
+    rooms: [[Room; ROOMS_HORIZONTAL]; ROOMS_VERTICAL],
+    level: usize,
+}
+
+impl LevelGenerator {
+    pub fn generate(level: usize, first: bool, last: bool) -> Self {
+        let mut rng = rand::thread_rng();
+        let mut rooms = [[Room::new(); ROOMS_HORIZONTAL]; ROOMS_VERTICAL];
+        let mut graph = UnGraph::<(usize, usize), u16>::default();
+
+        // trick the room_connectable function into failing on the first iteration
+        rooms[0][0].kind = RoomType::BasicRoom;
+
+        while !LevelGenerator::rooms_connectable(&rooms) {
+            let mut room_types: Vec<RoomType> = Vec::with_capacity(ROOMS_HORIZONTAL * ROOMS_VERTICAL);
+            // level 0 contains a start room, all others contain a stair up
+            if first {
+                room_types.push(RoomType::Start);
+            } else {
+                room_types.push(RoomType::StairUp);
+            }
+            // level 24 (the last) contains an end room, all others a stair down
+            if last {
+                room_types.push(RoomType::End);
+            } else {
+                room_types.push(RoomType::StairDown);
+            }
+            room_types.push(RoomType::MonsterRoom);
+            room_types.push(RoomType::TreasureRoom);
+            // generate a random set of rooms and shuffle them
+            for _ in room_types.len()..ROOMS_HORIZONTAL * ROOMS_VERTICAL {
+                match rng.gen_range(1..=100) {
+                    // TODO tune room type distribution
+                    1..=33 => { room_types.push(RoomType::EmptyRoom) }
+                    34..=66 => { room_types.push(RoomType::TreasureRoom) }
+                    67..=90 => { room_types.push(RoomType::MonsterRoom) }
+                    _ => { room_types.push(RoomType::BasicRoom) }
+                }
+            }
+            room_types.shuffle(&mut rng);
+
+            graph.clear();
+            // place the rooms in the array an add nodes to the graph for every non empty room
+            for c in 0..ROOMS_VERTICAL {
+                for r in 0..ROOMS_HORIZONTAL {
+                    rooms[c][r].kind = room_types.pop().unwrap();
+                    if rooms[c][r].kind != RoomType::EmptyRoom {
+                        rooms[c][r].random(&mut rng);
+                        graph.add_node((c, r));
+                    }
+                }
+            }
+        }
+
+        // add edges to the graph connecting each room to all of its neighbours (max 4 of them)
+        for c in 0..ROOMS_VERTICAL {
+            for r in 0..ROOMS_HORIZONTAL {
+                if rooms[c][r].kind == RoomType::EmptyRoom {
+                    continue;
+                }
+                let src_index = graph.node_indices().find(|i| graph[*i] == (c, r)).unwrap();
+                for r_1 in r + 1..ROOMS_HORIZONTAL {
+                    if rooms[c][r_1].kind != RoomType::EmptyRoom {
+                        let tgt_index = graph.node_indices().find(|i| graph[*i] == (c, r_1)).unwrap();
+                        // todo use random weight for edge
+                        graph.add_edge(src_index, tgt_index, 1);
+                        break;
+                    }
+                }
+                for c_1 in c + 1..ROOMS_VERTICAL {
+                    if rooms[c_1][r].kind != RoomType::EmptyRoom {
+                        let tgt_index = graph.node_indices().find(|i| graph[*i] == (c_1, r)).unwrap();
+                        // todo use random weight for edge
+                        graph.add_edge(src_index, tgt_index, 1);
+                        break;
+                    }
+                }
+            }
+        }
+
+        // calculate a minimum spanning tree
+        let mst: Graph<(usize, usize), u16, petgraph::Undirected> = Graph::from_elements(min_spanning_tree(&graph));
+        for edge in mst.raw_edges() {
+            let src = mst[edge.source()];
+            let tgt = mst[edge.target()];
+
+            let src_room = rooms[src.0][src.1];
+            let mut tgt_room = rooms[tgt.0][tgt.1];
+
+            // cols are the same, either up or down
+            if src.0 == tgt.0 {
+                let range = LevelGenerator::range_overlap(src_room.get_x_range(), tgt_room.get_x_range());
+                let position: usize;
+                if range.is_empty() {
+                    position = range.start;
+                } else {
+                    position = rng.gen_range(range);
+                }
+                if src.1 < tgt.1 {
+                    // src to tgt
+                    rooms[src.0][src.1].connection_down = Some(ConnectionInfo { offset: position, distance: tgt.1 - src.1 });
+                } else {
+                    // tgt to src
+                    tgt_room.connection_down = Some(ConnectionInfo { offset: position, distance: src.1 - tgt.1 });
+                }
+            }
+            // rows are the same, either left or right
+            if src.1 == tgt.1 {
+                let range = LevelGenerator::range_overlap(src_room.get_y_range(), tgt_room.get_y_range());
+                let mut position: usize;
+                if range.is_empty() {
+                    position = range.start;
+                } else {
+                    position = rng.gen_range(range);
+                }
+                if src.1 == 0 && position == 0 {
+                    position = 1;
+                }
+                if src.0 < tgt.0 {
+                    // src to tgt
+                    rooms[src.0][src.1].connection_right = Some(ConnectionInfo { offset: position, distance: tgt.0 - src.0 });
+                } else {
+                    // tgt to src
+                    tgt_room.connection_right = Some(ConnectionInfo { offset: position, distance: src.1 - tgt.1 });
+                }
+            }
+        }
+
+        LevelGenerator {
+            rooms,
+            level,
+        }
+    }
+
+    fn range_overlap(r1: Range<usize>, r2: Range<usize>) -> Range<usize> {
+        max(r1.start, r2.start)..min(r1.end, r2.end)
+    }
+
+    /// Verifies that for a given matrix of rooms each room has at least one other room in the
+    /// same row or column.
+    fn rooms_connectable(rooms: &[[Room; ROOMS_HORIZONTAL]; ROOMS_VERTICAL]) -> bool {
+        for c in 0..ROOMS_VERTICAL {
+            for r in 0..ROOMS_HORIZONTAL {
+                if rooms[c][r].kind != RoomType::EmptyRoom {
+                    let mut connected = 0;
+                    for c1 in 0..ROOMS_VERTICAL {
+                        if rooms[c1][r].kind != RoomType::EmptyRoom {
+                            connected += 1;
+                        }
+                    }
+                    for r1 in 0..ROOMS_HORIZONTAL {
+                        if rooms[c][r1].kind != RoomType::EmptyRoom {
+                            connected += 1;
+                        }
+                    }
+                    if connected <= 2 {
+                        return false;
+                    }
+                }
+            }
+        }
+        return true;
+    }
+    pub fn render(&self) -> Level {
+        let mut rng = rand::thread_rng();
+        let mut structure = [[StructureElement::Wall; 1 + ROOMS_HORIZONTAL * ROOM_HEIGHT]; 1 + ROOMS_VERTICAL * ROOM_WIDTH];
+        let mut artifacts: Vec<Box<dyn Artifact>> = Vec::with_capacity(10);
+        let mut enemies: Vec<Box<dyn Monster>> = Vec::with_capacity(10);
+        let mut start_x: usize = 0;
+        let mut start_y: usize = 0;
+        let mut end_x: usize = 0;
+        let mut end_y: usize = 0;
+        for c in 0..ROOMS_VERTICAL {
+            for r in 0..ROOMS_HORIZONTAL {
+                let top = 1 + r * ROOM_HEIGHT;
+                let left = 1 + c * ROOM_WIDTH;
+                let room = self.rooms[c][r];
+                for x in 0..room.width {
+                    for y in 0..room.height {
+                        structure[left + room.offset_x + x][top + room.offset_y + y] = StructureElement::Floor;
+                    }
+                }
+                if room.kind == RoomType::TreasureRoom {
+                    let t_x = left + room.offset_x + rng.gen_range(0..room.width);
+                    let t_y = top + room.offset_y + rng.gen_range(0..room.height);
+                    // TODO randomize artifacts
+                    match rng.gen_range(1..=100) {
+                        1..=50 => { artifacts.push(Box::new(Chest::new(Position::new(self.level, t_x, t_y)))); }
+                        _ => { artifacts.push(Box::new(Potion::new(Position::new(self.level, t_x, t_y)))); }
+                    };
+                }
+                if room.kind == RoomType::MonsterRoom {
+                    let t_x = left + room.offset_x + rng.gen_range(0..room.width);
+                    let t_y = top + room.offset_y + rng.gen_range(0..room.height);
+                    // TODO randomize enemies here
+                    match rng.gen_range(1..=100) {
+                        1..=50 => {
+                            enemies.push(Box::new(Orc::new_with_position(Position::new(self.level, t_x, t_y))));
+                        }
+                        _ => {
+                            enemies.push(Box::new(Rat::new_with_position(Position::new(self.level, t_x, t_y))));
+                        }
+                    };
+                }
+
+                if room.kind == RoomType::End || room.kind == RoomType::StairDown {
+                    end_x = left + room.offset_x + rng.gen_range(0..room.width);
+                    end_y = top + room.offset_y + rng.gen_range(0..room.height);
+                }
+                if room.kind == RoomType::StairDown {
+                    structure[end_x][end_y] = StructureElement::StairDown;
+                }
+                if room.kind == RoomType::End {
+                    structure[end_x][end_y] = StructureElement::End;
+                }
+
+                if room.kind == RoomType::Start || room.kind == RoomType::StairUp {
+                    start_x = left + room.offset_x + rng.gen_range(0..room.width);
+                    start_y = top + room.offset_y + rng.gen_range(0..room.height);
+                }
+                if room.kind == RoomType::StairUp {
+                    structure[start_x][start_y] = StructureElement::StairUp;
+                }
+                if room.kind == RoomType::Start {
+                    structure[start_x][start_y] = StructureElement::Start;
+                }
+            }
+        }
+        //
+        for c in 0..ROOMS_VERTICAL {
+            for r in 0..ROOMS_HORIZONTAL {
+                let src_room = self.rooms[c][r];
+                if let Some(x_conn) = src_room.connection_down {
+                    let tgt_room = self.rooms[c][r + x_conn.distance];
+                    let top = 1 + r * ROOM_HEIGHT + src_room.offset_y;
+                    let left = 1 + c * ROOM_WIDTH + x_conn.offset;
+                    let bottom = 1 + (r + x_conn.distance) * ROOM_HEIGHT + tgt_room.offset_y + tgt_room.height;
+                    for i in top..bottom {
+                        if structure[left][i] == StructureElement::Wall {
+                            structure[left][i] = StructureElement::Floor;
+                        }
+                    }
+                }
+                if let Some(y_conn) = src_room.connection_right {
+                    let tgt_room = self.rooms[c + y_conn.distance][r];
+
+                    let top = 1 + r * ROOM_HEIGHT + src_room.offset_y + y_conn.offset - 1;
+                    let left = 1 + c * ROOM_WIDTH + src_room.offset_x;
+                    let right = 1 + (c + y_conn.distance) * ROOM_WIDTH + tgt_room.offset_x + tgt_room.width;
+                    for i in left..right {
+                        if structure[i][top] == StructureElement::Wall {
+                            structure[i][top] = StructureElement::Floor;
+                        }
+                    }
+                }
+            }
+        }
+        Level {
+            level: self.level,
+            structure,
+            discovered: [[false; 1 + ROOMS_HORIZONTAL * ROOM_HEIGHT]; 1 + ROOMS_VERTICAL * ROOM_WIDTH],
+            monsters: enemies,
+            artifacts,
+            start: (start_x, start_y),
+            end: (end_x, end_y),
+        }
+    }
+}
+
+#[test]
+fn test_level_gen() {
+    let level = LevelGenerator::generate(23, false, false).render();
+    assert_eq!(level.level, 23);
+    assert_ne!(level.start, (0, 0));
+    assert_ne!(level.end, (0, 0));
+    assert_ne!(level.start, level.end);
+    assert_ne!(level.monsters.len(), 0);
+    assert_ne!(level.artifacts.len(), 0);
+}

src/level_widget.rs

@@ -0,0 +1,93 @@
+use ratatui::buffer::Buffer;
+use ratatui::layout::Rect;
+use ratatui::style::Color;
+use ratatui::widgets::{StatefulWidget, Widget};
+
+use crate::game::Game;
+use crate::level::StructureElement;
+
+const FG_BROWN: Color = Color::Rgb(186, 74, 0);
+
+pub struct LevelWidget {}
+
+impl LevelWidget {
+    fn set_cell(&self, buf: &mut Buffer, x: u16, y: u16, symbol: &str, fg: Color, bg: Color) {
+        buf.
+            get_mut(x, y).
+            set_symbol(symbol).
+            set_bg(bg).
+            set_fg(fg);
+    }
+}
+
+impl StatefulWidget for LevelWidget {
+    type State = Game;
+
+    fn render(self, area: Rect, buf: &mut Buffer, state: &mut Self::State) {
+        let al: u16 = area.left();
+        let at: u16 = area.top();
+
+        {
+            let player = state.get_mutable_player();
+            let player_pos = player.get_immutable_position();
+            let player_level = player_pos.get_level();
+
+            // draw the level elements
+            for x in al..area.right() {
+                for y in at..area.bottom() {
+                    let level = state.get_mutable_level(player_level);
+                    let level_x = (x - al) as i16;
+                    let level_y = (y - at) as i16;
+                    match level.get_element(level_x, level_y) {
+                        (Some(structure_element), None, None) => {
+                            match structure_element {
+                                StructureElement::Start => {
+                                    self.set_cell(buf, x, y, "α", Color::Black, Color::Gray);
+                                }
+                                StructureElement::End => {
+                                    self.set_cell(buf, x, y, "Ω", Color::Black, Color::Gray);
+                                }
+                                StructureElement::Wall => {
+                                    // TODO add fancy walls
+                                    self.set_cell(buf, x, y, "#", FG_BROWN, Color::Gray);
+                                }
+                                StructureElement::Floor => {
+                                    self.set_cell(buf, x, y, " ", FG_BROWN, Color::Gray);
+                                }
+                                StructureElement::StairDown => {
+                                    self.set_cell(buf, x, y, ">", Color::Black, Color::Gray);
+                                }
+                                StructureElement::StairUp => {
+                                    self.set_cell(buf, x, y, "<", Color::Black, Color::Gray);
+                                }
+                                StructureElement::Unknown => {
+                                    self.set_cell(buf, x, y, "▒", Color::DarkGray, Color::Gray);
+                                }
+                            }
+                        }
+                        (_, Some(m), _) => {
+                            let (s, c) = m.get_representation();
+                            self.set_cell(buf, x, y, s, c, Color::Gray);
+                        }
+                        (_, _, Some(t)) => {
+                            let (s, c) = t.get_representation();
+                            self.set_cell(buf, x, y, s, c, Color::Gray);
+                        }
+                        (None, None, None) => {}
+                    };
+                }
+            }
+        }
+        {
+            let player = state.get_mutable_player();
+            let player_pos = player.get_immutable_position();
+            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);
+        }
+    }
+}
+
+impl Widget for LevelWidget {
+    fn render(self, _area: Rect, _buf: &mut Buffer) {}
+}

src/main.rs

@@ -1,19 +1,150 @@
-use crate::game::Game;
+use std::io::Result;
+use std::io::stdout;
+
+use crossterm::{
+    event::{self, KeyCode, KeyEventKind},
+    ExecutableCommand,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use ratatui::{
+    prelude::{CrosstermBackend, Stylize, Terminal},
+    widgets::Paragraph,
+};
+use ratatui::prelude::*;
+use ratatui::widgets::{Block, Borders, BorderType, Wrap};
+use ratatui::widgets::block::{Position, Title};
+use whoami::realname;
+
+use crate::game::{Game, GameState};
+use crate::level_widget::LevelWidget;
+// use crate::level_widget::LevelWidget;
 use crate::player::Player;
 
 mod game;
 mod player;
 mod level;
 mod position;
-mod monster;
+mod level_widget;
+mod level_generator;
 mod artifacts;
+mod monster;
 
-fn main() {
+//
-    let mut p = Player::new("Teddy Tester", 10);
+fn main() -> Result<()> {
-    let g = Game::new(&mut p);
+    let mut game = Game::new(Player::new(realname().as_str(), 10));
 
-    println!("{}",g.player.get_name());
+    stdout().execute(EnterAlternateScreen)?;
-    println!("{}",g.player.get_life());
+    enable_raw_mode()?;
-    g.player.change_life(-1);
+    let mut terminal = Terminal::new(CrosstermBackend::new(stdout()))?;
-    println!("{}",g.player.get_life());
+    terminal.clear()?;
+
+    loop {
+        terminal.draw(|frame| {
+            let mut area = frame.size();
+            frame.render_widget(Block::default().style(Style::default().bg(Color::Green)), area);
+
+            if area.width > 80 {
+                area.x = (area.width - 80) / 2;
+                area.width = 80;
+            }
+            if area.height > 25 {
+                area.y = (area.height - 25) / 2;
+                area.height = 25;
+            }
+
+            let map_area = Rect {
+                x: area.x,
+                y: area.y,
+                width: level::LEVEL_WIDTH as u16,
+                height: level::LEVEL_HEIGHT as u16,
+            };
+            frame.render_stateful_widget(LevelWidget {}, map_area, &mut game);
+
+            let stats_area = Rect {
+                x: area.x + 50,
+                y: area.y,
+                width: 30,
+                height: 25,
+            };
+            frame.render_widget(
+                Paragraph::new(format!("{}\nHealth: {}/{}\nGold: {}\nLevel: {}",
+                                       game.get_player().get_name(),
+                                       game.get_player().get_life(),
+                                       game.get_player().get_max_life(),
+                                       game.get_player().get_gold(),
+                                       game.get_player().get_immutable_position().get_level()))
+                    .white()
+                    .on_blue(),
+                stats_area,
+            );
+        })?;
+        if event::poll(std::time::Duration::from_millis(16))? {
+            if let event::Event::Key(key) = event::read()? {
+                if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('q') {
+                    break;
+                }
+                if key.kind == KeyEventKind::Press {
+                    let new_pos = match key.code {
+                        KeyCode::Left => { game.move_player(-1, 0) }
+                        KeyCode::Right => { game.move_player(1, 0) }
+                        KeyCode::Up => { game.move_player(0, -1) }
+                        KeyCode::Down => { game.move_player(0, 1) }
+                        _ => { (0, 0) }
+                    };
+                    if !game.player_fights_monster() {
+                        // player attacked monster but did not kill it
+                        game.move_player(new_pos.0, new_pos.1);
+                    }
+                    game.player_collects_artifact();
+                    game.update_level();
+                    if game.get_game_state() != GameState::RUNNING {
+                        break;
+                    }
+                }
+            }
+        }
+    }
+    loop {
+        let _ = terminal.draw(|frame| {
+            let mut area = frame.size();
+            let w = area.width / 2;
+            let h = area.height / 2;
+            area.x += w - 20;
+            area.y += h - 10;
+            area.width = 40;
+            area.height = 20;
+            let block = Block::default()
+                .title("Game ended")
+                .title(Title::from("Press `q` to quit!").position(Position::Bottom))
+                .borders(Borders::ALL)
+                .border_style(Style::default().fg(Color::White))
+                .border_type(BorderType::Rounded)
+                .style(Style::default().bg(Color::Black));
+            let mut text = match game.get_game_state() {
+                GameState::RUNNING => {
+                    "Quitting is for cowards! You'll better try again!".to_string()
+                }
+                GameState::LOST => {
+                    "Sorry, you died in the dungeon. Better luck next time!".to_string()
+                }
+                GameState::WON => {
+                    "Congratulation! You mastered your way through the dungeon and won the game.".to_string()
+                }
+            };
+            text += format!("\nYou collected {} gold.", game.get_player().get_gold()).as_str();
+            let paragraph = Paragraph::new(text).block(block).wrap(Wrap { trim: true });
+            frame.render_widget(paragraph, area);
+        });
+        if event::poll(std::time::Duration::from_millis(16))? {
+            if let event::Event::Key(key) = event::read()? {
+                if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('q') {
+                    break;
+                }
+            }
+        }
+    }
+
+    stdout().execute(LeaveAlternateScreen)?;
+    disable_raw_mode()?;
+    Ok(())
 }

src/monster.rs

@@ -1,33 +1,104 @@
+use ratatui::prelude::Color;
+
 use crate::position::Position;
 
-pub struct Monster {
+pub trait Monster {
-    life: usize,
+    fn is_dead(&self) -> bool;
-    position: Position,
+    fn get_representation(&self) -> (&str, Color);
+    fn decrease_life(&mut self, by: usize);
+    fn get_immutable_position(&self) -> &Position;
+    #[cfg(test)]
+    fn get_position(&mut self) -> &mut Position;
+    #[cfg(test)]
+    fn get_life(&self) -> usize;
 }
 
-impl Monster {
+macro_rules! default_monster {
-    pub fn new(life: usize) -> Self {
+    ($($t:ty),+ $(,)?) => ($(
-        Monster {
+        impl Monster for $t {
-            life,
+            fn is_dead(&self) -> bool { self.life <= 0 }
-            position: Position::new(0, 0, 0),
+            fn get_representation(&self) -> (&str, Color) { (&self.symbol, self.color) }
-        }
+            fn decrease_life(&mut self, by: usize) {
-    }
-    pub fn get_life(&self) -> usize { self.life }
-    pub fn is_dead(&self) -> bool { self.life <= 0 }
-    pub fn decrease_life(&mut self, by: usize) {
                 self.life = self.life.saturating_sub(by);
             }
-    pub fn get_position(&mut self) -> &mut Position {
+            fn get_immutable_position(&self) -> &Position {
-        &mut self.position
-    }
-    pub fn get_immutable_position(&self) -> &Position {
                 &self.position
             }
+            #[cfg(test)]
+            fn get_position(&mut self) -> &mut Position {
+                &mut self.position
             }
+            #[cfg(test)]
+            fn get_life(&self) -> usize { self.life }
+        }
+    )+)
+}
+
+pub struct Rat {
+    life: usize,
+    position: Position,
+    symbol: String,
+    color: Color,
+}
+
+impl Rat {
+    #[cfg(test)]
+    pub fn new(life: usize) -> Self {
+        Self {
+            life,
+            position: Position::new(0, 0, 0),
+            symbol: String::from("R"),
+            color: Color::Black,
+        }
+    }
+    pub fn new_with_position(position: Position) -> Self {
+        Self {
+            life: 2,
+            position,
+            symbol: String::from("R"),
+            color: Color::Black,
+        }
+    }
+    #[cfg(test)]
+    pub fn get_life(&self) -> usize { self.life }
+}
+default_monster!(Rat);
+
+pub struct Orc {
+    life: usize,
+    position: Position,
+    symbol: String,
+    color: Color,
+}
+
+impl Orc {
+    #[cfg(test)]
+    pub fn new(life: usize) -> Self {
+        Self {
+            life,
+            position: Position::new(0, 0, 0),
+            symbol: String::from("O"),
+            color: Color::DarkGray,
+        }
+    }
+    pub fn new_with_position(position: Position) -> Self {
+        Self {
+            life: 4,
+            position,
+            symbol: String::from("O"),
+            color: Color::DarkGray,
+        }
+    }
+    #[cfg(test)]
+    pub fn get_life(&self) -> usize { self.life }
+}
+
+default_monster!(Orc);
+
 
 #[test]
 fn monsters_can_move() {
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     assert_eq!(m.get_position(), &Position::new(0, 0, 0));
     m.get_position().change(1, 2);
     assert_eq!(m.get_position(), &Position::new(0, 1, 2));
@@ -40,7 +111,7 @@ fn monsters_can_move() {
 
 #[test]
 fn monsters_can_die() {
-    let mut m = Monster::new(2);
+    let mut m = Rat::new(2);
     assert_eq!(m.get_life(), 2);
     assert_eq!(m.is_dead(), false);
     m.decrease_life(1);

src/player.rs

@@ -1,4 +1,5 @@
 use std::cmp::{max, min};
+
 use crate::position::Position;
 
 pub struct Player {
@@ -28,9 +29,15 @@ impl Player {
     pub fn get_life(&self) -> i16 {
         self.life
     }
+    pub fn get_max_life(&self) -> i16 {
+        self.max_life
+    }
     pub fn get_position(&mut self) -> &mut Position {
         &mut self.position
     }
+    pub fn get_immutable_position(&self) -> &Position {
+        &self.position
+    }
 
     /// add the given amount to the players gold stash
     pub fn retrieve_gold(&mut self, amount: usize) { self.gold += amount }
@@ -70,13 +77,13 @@ fn test_change_life() {
         max_life: 10,
         gold: 0,
     };
-    assert_eq!(p.life, 5);
+    assert_eq!(p.get_life(), 5);
     p.change_life(-2);
-    assert_eq!(p.life, 3);
+    assert_eq!(p.get_life(), 3);
     p.change_life(10);
-    assert_eq!(p.life, 10);
+    assert_eq!(p.get_life(), 10);
     p.change_life(-12);
-    assert_eq!(p.life, 0);
+    assert_eq!(p.get_life(), 0);
 }
 
 #[test]
@@ -90,4 +97,17 @@ fn player_can_move() {
     p.get_position().set(1, 2, 3);
     p.get_position().change(2, 1);
     assert_eq!(p.get_position(), &Position::new(1, 4, 4));
+    assert_eq!(p.get_immutable_position(), &Position::new(1, 4, 4));
+}
+
+#[test]
+fn test_max_life() {
+    let p = Player {
+        name: "Teddy Tester".to_string(),
+        position: Position::new(0, 1, 1),
+        life: 5,
+        max_life: 10,
+        gold: 0,
+    };
+    assert_eq!(p.get_max_life(), 10);
 }

src/position.rs

@@ -1,3 +1,5 @@
+use std::cmp::max;
+
 #[derive(PartialEq, Debug)]
 pub struct Position {
     level: usize,
@@ -13,9 +15,10 @@ impl Position {
             y,
         }
     }
-    pub fn change(&mut self, dx: i16, dy: i16) {
+    pub fn change(&mut self, dx: i16, dy: i16) -> (usize, usize) {
-        self.x = ((self.x as i16) + dx) as usize;
+        self.x = max((self.x as i16) + dx, 0) as usize;
-        self.y = ((self.y as i16) + dy) as usize;
+        self.y = max((self.y as i16) + dy, 0) as usize;
+        (self.x, self.y)
     }
     pub fn set(&mut self, level: usize, x: usize, y: usize) {
         self.level = level;
@@ -33,3 +36,33 @@ impl Position {
 
     pub fn get_y(&self) -> usize { self.y }
 }
+
+#[test]
+fn test_position_change() {
+    let mut p = Position::new(0, 10, 10);
+
+    let res = p.change(-1, 1);
+    assert_eq!(res, (9, 11));
+    assert_eq!(p.get_x(), 9);
+    assert_eq!(p.get_y(), 11);
+
+    let res = p.change(-9, 1);
+    assert_eq!(res, (0, 12));
+    assert_eq!(p.get_x(), 0);
+    assert_eq!(p.get_y(), 12);
+
+    let res = p.change(-1, -13);
+    assert_eq!(res, (0, 0));
+    assert_eq!(p.get_x(), 0);
+    assert_eq!(p.get_y(), 0);
+}
+
+#[test]
+fn test_position_set() {
+    let mut p = Position::new(0, 10, 10);
+
+    p.set(1, 2, 3);
+    assert_eq!(p.get_level(), 1);
+    assert_eq!(p.get_x(), 2);
+    assert_eq!(p.get_y(), 3);
+}