mod utils;

use wasm_bindgen::prelude::*;
use rand::Rng;

// When the `wee_alloc` feature is enabled, use `wee_alloc` as the global
// allocator.
#[cfg(feature = "wee_alloc")]
#[global_allocator]
static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;

#[wasm_bindgen]
extern {
    fn alert(s: &str);
}


#[wasm_bindgen]
pub fn generate(len: usize, lower: bool, upper: bool, number: bool, special: bool) -> String {
    let mut upper_charset: Vec<char> = String::from("ABCDEFGHIJKLMNOPQRSTUVWXYZ").chars().collect();
    let mut lower_charset: Vec<char> = String::from("abcdefghijklmnopqrstuvwxyz").chars().collect();
    let mut number_charset: Vec<char> = String::from("1234567890").chars().collect();
    let mut special_charset: Vec<char> = String::from("!@#$%^&*()+{}[]").chars().collect();
    let mut result: Vec<char> = Vec::new();

    let mut rng = rand::thread_rng();

    if lower {
        result.append(&mut lower_charset);
    }

    if upper {
        result.append(&mut upper_charset);
    }

    if number {
        result.append(&mut number_charset);
    }

    if special {
        result.append(&mut special_charset);
    }


    (0..len)
        .map(|_| {
            let idx = rng.gen_range(0..result.len());
            result[idx] as char
        })
        .collect()
}