feat: snake's movement and apple

src/main.rs

@@ -1,3 +1,158 @@
-fn main() {
-    println!("Hello, world!");
+use crossterm::{
+    cursor,
+    event::{self, Event, KeyCode, KeyEvent},
+    style::{Color, SetForegroundColor, ResetColor},
+    terminal::{self, Clear, ClearType},
+    ExecutableCommand,
+};
+use std::{
+    cmp::min, collections::VecDeque, io::{Write, stdout}
+};
+use std::time::Duration;
+use rand::random_range;
+
+#[derive(PartialEq, Eq)]
+enum Direction {
+    Up,
+    Down,
+    Left,
+    Right,
+}
+
+fn read_inputs() -> Option<KeyCode> {
+    if event::poll(Duration::from_millis(100)).unwrap() {
+        if let Event::Key(KeyEvent { code, .. }) = event::read().unwrap() {
+            return Some(code);
+        }
+    }
+
+    None
+}
+
+fn draw_gui() {
+    let mut stdout = stdout();
+    stdout.execute(cursor::MoveTo(0, 0)).unwrap();
+    println!("SNAKE TUI");
+    stdout.execute(cursor::MoveTo(0, 1)).unwrap();
+    stdout.execute(SetForegroundColor(Color::White)).unwrap();
+    println!("┌───────────────────────────────────┐");
+    for i in 2..19 {
+        stdout.execute(cursor::MoveTo(0, i)).unwrap();
+        println!("│                                   │")        
+    }
+    stdout.execute(cursor::MoveTo(0, 19)).unwrap();
+    println!("└───────────────────────────────────┘");
+
+    stdout.execute(ResetColor).unwrap();
+    stdout.flush().unwrap();
+}
+
+fn win() {
+    let mut stdout = stdout();
+    stdout.execute(cursor::MoveTo(0, 0)).unwrap();
+    println!("WIN");
+
+    loop {
+        match read_inputs() {
+            Some(KeyCode::Char('r')) => break,
+            _ => {},
+        }
+    }
+}
+
+fn game_over() {
+    loop {
+        match read_inputs() {
+            Some(KeyCode::Char('r')) => break,
+            _ => {},
+        }
+    }
+}
+
+fn main() {
+    const MAX_X : u16 = 16;
+    const MAX_Y: u16 = 16;
+
+    let mut head_x: u16 = 8;
+    let mut head_y: u16 = 8;
+    let mut body_length: usize = 0;
+    let mut body: VecDeque<(u16,u16)> = Default::default();
+    let mut direction: Direction = Direction::Up;
+
+    let mut apple_x: u16 = random_range(0..17);
+    let mut apple_y: u16 = random_range(0..17);
+
+    let mut stdout = stdout();
+    terminal::enable_raw_mode().unwrap();
+    stdout.execute(cursor::Hide).unwrap();
+
+    loop {
+        match read_inputs() {
+            Some(KeyCode::Up) => direction = if direction != Direction::Down {Direction::Up} else {direction},
+            Some(KeyCode::Down) => direction = if direction != Direction::Up {Direction::Down} else {direction},
+            Some(KeyCode::Left) => direction = if direction != Direction::Right {Direction::Left} else {direction},
+            Some(KeyCode::Right) => direction = if direction != Direction::Left {Direction::Right} else {direction},
+            Some(KeyCode::Char('q')) => break,
+            _ => {},
+        }
+
+        // MOVE
+        if body.len() > body_length {
+            body.pop_back();
+        }
+        body.push_front((head_x, head_y));
+        
+        match direction {
+            Direction::Up => head_y = head_y.saturating_sub(1),
+            Direction::Down => head_y = min(head_y+1, MAX_Y),
+            Direction::Left => head_x = head_x.saturating_sub(1),
+            Direction::Right => head_x = min(head_x+1, MAX_X),
+        }
+
+        
+        // CHECKS
+        // if body_length == &MAX_X*&MAX_Y { win(); }
+        if (head_x, head_y) == (apple_x, apple_y) {
+            body_length += 1;
+
+            loop {
+                apple_x = random_range(0..17);
+                apple_y = random_range(0..17);
+
+                if !body.contains(&(apple_x, apple_y)) { break; }
+            }
+        }
+
+        // DRAW
+        stdout.execute(Clear(ClearType::All)).unwrap();
+        draw_gui();
+
+        // Apple
+        stdout.execute(cursor::MoveTo((apple_x+1)*2, apple_y+2)).unwrap();
+        stdout.execute(SetForegroundColor(Color::Red)).unwrap();
+        print!("⯀");
+
+        // Snake
+        stdout.execute(cursor::MoveTo((head_x+1)*2, head_y+2)).unwrap();
+        stdout.execute(SetForegroundColor(Color::Green)).unwrap();
+        match direction {
+            Direction::Up => print!("⯅"),
+            Direction::Down => print!("⯆"),
+            Direction::Left => print!("⯇"),
+            Direction::Right => print!("⯈"),
+        }
+
+        for (x, y) in &body {
+            stdout.execute(cursor::MoveTo((x+1)*2, y+2)).unwrap();
+            print!("⯀")
+        }
+
+        stdout.execute(ResetColor).unwrap();
+        stdout.flush().unwrap();
+    }
+
+    stdout.execute(Clear(ClearType::All)).unwrap();
+    stdout.execute(cursor::MoveTo(0, 0)).unwrap();
+    stdout.execute(cursor::Show).unwrap();
+    terminal::disable_raw_mode().unwrap();
 }