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#![doc(
html_logo_url = "https://raw.githubusercontent.com/tarcieri/bats/batcave/img/cutebat.png",
html_root_url = "https://docs.rs/bats/0.1.0"
)]
#![warn(missing_docs, rust_2018_idioms)]
use crossterm_cursor::cursor;
use crossterm_terminal::terminal;
use gumdrop::Options;
use rand::{thread_rng, Rng};
use std::{thread::sleep, time::Duration};
pub const BAT: char = '🦇';
pub const CRAB: char = '🦀';
pub const HALLOWEEN_THINGS: &[char] = &['🦇', '🎃', '👻', '💀', '🕸', '🧙'];
#[derive(Debug, Default, Options)]
pub struct Bats {
#[options(help = "print help message")]
help: bool,
#[options(short = "c", long = "char", help = "character to print")]
char: Option<char>,
#[options(long = "crab", help = "draw crabs")]
crab: bool,
#[options(
short = "s",
long = "speed",
help = "speed factor (default 15, max 255)"
)]
pub speed: Option<u8>,
#[options(long = "halloween", help = "enable halloween mode")]
pub halloween: bool,
}
impl Bats {
pub fn run(&self) {
println!("🦇 BATS! 🦇");
sleep(Duration::from_millis(250));
terminal()
.clear(crossterm_terminal::ClearType::All)
.unwrap();
let cursor = cursor();
cursor.hide().unwrap();
cursor.goto(0, 0).unwrap();
let thing = self.thing_to_draw();
let is_halloween = self.is_it_halloween();
loop {
if is_halloween {
self.draw_halloween();
} else {
self.draw(thing);
}
}
}
pub fn draw_halloween(&self) {
self.draw(HALLOWEEN_THINGS[thread_rng().gen_range(0, HALLOWEEN_THINGS.len() - 1)]);
}
pub fn draw(&self, thing: char) {
let mut rng = thread_rng();
let terminal = terminal();
let (term_width, term_height) = terminal.size().unwrap();
let cursor = cursor();
let y_position = cursor.pos().unwrap().1;
let start_pos = term_width - 2;
let end_pos = rng.gen_range(0, start_pos);
let mut delay = u64::from(10 + (start_pos - end_pos) * 2);
let delay_scale = rng.gen_range(self.speed_factor(), self.speed_factor() * 2);
for pos in (end_pos..start_pos).rev() {
cursor.goto(pos, y_position).unwrap();
terminal.write(thing).unwrap();
sleep(Duration::from_millis(delay / delay_scale));
delay -= 1;
if pos != end_pos {
cursor.goto(pos, y_position).unwrap();
terminal.write(" ").unwrap();
}
}
if y_position < term_height - 1 {
cursor.goto(0, y_position + 1).unwrap();
} else {
terminal.clear(crossterm_terminal::ClearType::All).unwrap();
cursor.goto(0, 0).unwrap();
}
sleep(Duration::from_millis(256 / self.speed_factor()));
}
fn thing_to_draw(&self) -> char {
if self.crab {
if self.char.is_none() {
CRAB
} else {
panic!("both --char and --crab options passed");
}
} else {
self.char.unwrap_or(BAT)
}
}
fn speed_factor(&self) -> u64 {
u64::from(self.speed.unwrap_or(15))
}
fn is_it_halloween(&self) -> bool {
if self.halloween {
return true;
}
use chrono::Datelike;
let today = chrono::Local::today();
today.month() == 10 && today.day() == 31
}
}