1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
use std::fmt;
use std::fmt::Formatter;
use rand::Rng;
pub struct RollResult {
rolls: Vec<u32>,
}
impl RollResult {
fn new() -> Self {
RollResult {
rolls: Vec::new(),
}
}
fn add_roll(&mut self, roll: u32) {
self.rolls.push(roll);
}
fn total(&self) -> u32 {
self.rolls.iter().sum()
}
}
impl fmt::Display for RollResult {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.total())
}
}
/// Roll a single die with the specified number of sides.
pub fn roll_die(sides: u32) -> u32 {
let mut rng = rand::thread_rng();
rng.gen_range(1..=sides)
}
/// Parse and roll dice from a dice formula (e.g. "4d6+2" or "d12*3").
pub fn roll_formula(formula: &str) -> Option<RollResult> {
let delimiters = ['d', '+', '-', '*', '/']; // Only d implemented right now.
let parts: Vec<&str> = formula.split(|c| delimiters.contains(&c)).collect();
if parts.len() < 2 {
return None;
}
let num_dice = if parts[0].is_empty() {
1
} else {
match parts[0].parse::<u32>() {
Ok(num) => num,
Err(_) => return None,
}
};
let sides = match parts[1].parse::<u32>() {
Ok(num) => num,
Err(_) => return None,
};
let mut roll_result = RollResult::new();
for _ in 0..num_dice {
let roll = roll_die(sides);
roll_result.add_roll(roll);
}
Some(roll_result)
}
|
