// Do not change
pub const NUM_KEYS: usize = 30;
pub const ROW_LENGTH: usize = 10;

pub const KEY_CHARS: [char; NUM_KEYS] = [
    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S',
    'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '/', '.', ',', '\'',
];

pub const KEY_TO_FINGER: [usize; NUM_KEYS] = [
    0, 1, 2, 3, 3, 4, 4, 5, 6, 7, 0, 1, 2, 3, 3, 4, 4, 5, 6, 7, 0, 1, 2, 3, 3, 4, 4, 5, 6, 7,
];

pub fn canonicalise(inp: char) -> Option<char> {
    if inp.is_ascii_alphabetic() {
        return Some(inp.to_ascii_uppercase());
    } else {
        match inp {
            '.' => Some('.'),
            '>' => Some('.'),
            ',' => Some(','),
            '<' => Some(','),
            '/' => Some('/'),
            '?' => Some('/'),
            '\'' => Some('\''),
            '"' => Some('\''),
            _ => None,
        }
    }
}

const fn build_lookup_table() -> [usize; 128] {
    let mut result = [0; 128];
    let mut i = 0;

    while i < NUM_KEYS {
        result[KEY_CHARS[i] as usize] = i;
        i += 1;
    }
    return result;
}

pub const CHAR_TO_INDEX: [usize; 128] = build_lookup_table();