#[derive(Copy, Clone, Debug, PartialEq)]
enum LevelElement {
    Wall,
    Floor,
    StairDown,
    StairUp,
}

#[derive(Copy, Clone, Debug, PartialEq)]
pub struct Level {
    structure: [[LevelElement; 25]; 80],
}

impl Level {
    pub fn new() -> Level {
        let mut s = [[LevelElement::Wall; 25]; 80];
        s[4][4] = LevelElement::StairDown;
        s[75][20] = LevelElement::StairUp;
        Level {
            structure: s
        }
    }
    pub fn get_element(&self, x: usize, y: usize) -> Option<LevelElement> {
        if x >= 80 || y >= 25 {
            return None;
        }
        Some(self.structure[x][y])
    }
}

#[test]
fn test_get_element() {
    let l = Level::new();
    assert_eq!(l.get_element(0, 0).unwrap(), LevelElement::Wall);
    assert_eq!(l.get_element(4, 4).unwrap(), LevelElement::StairDown);
    assert_eq!(l.get_element(79, 24).unwrap(), LevelElement::Wall);
    assert_eq!(l.get_element(80, 25), None);
}