/// A dead simple library for handling user input.

use std::io::stdin;

/// A function to get a numerical array of a certain size from the user input.
/// 
/// ```
/// use ezin::get_array;
///
/// let vals: Vec<u32> = get_array(size);
/// ```
#[inline]
pub fn get_array<T>(size: u8) -> Vec<T>
where
    T: std::str::FromStr,
{
    let mut vals = Vec::new();
    let mut iterations = 0;
    while iterations < size {
        let tmp = get_number();
        if let Some(i) = tmp {
            vals.push(i);
            iterations += 1;
        }
    }
    vals
}

/// A function to get a number from user input.
///
/// ```
/// use ezin::get_number;
///
/// println!("Enter a number");
/// let val: Option<u32> = get_number();
///
/// if let Some(i) = val {
///     // Do Something
/// } else {
///     println!("Error. Invalid numerical input.");
///     return;
/// }
/// ```
#[inline]
pub fn get_number<T>() -> Option<T>
where
    T: std::str::FromStr,
{
    let s = get_string().trim().to_string();
    match s.parse::<T>() {
        Ok(i) => Some(i),
        Err(..) => None,
    }
}

/// A function to get a string from user input.
///
/// ``` 
/// use ezin::get_string;
///
/// println!("Enter a string.");
/// let s = get_string();
/// ```
#[inline]
pub fn get_string() -> String {
    let mut val = String::new();
    stdin().read_line(&mut val).expect("Invalid String Entry.");
    val
}