use serde::{Deserialize, Serialize};

use crate::constants::CHIP8_KEYBOARD;

#[derive(Clone, Copy, Default, Serialize, Deserialize, Debug)]
pub struct Keypad {
    keys: [bool; 0x10],
}

impl Keypad {
    pub fn format_as_string(&self) -> String {
        let mut return_value = String::new();
        // draw a 4x4 grid showing the keys with * filling the cells that are depressed
        for row in CHIP8_KEYBOARD.iter() {
            for (index, key) in row.iter().enumerate() {
                let is_lit = if self.keys[*key as usize] {
                    "*".to_string()
                } else {
                    char::from_digit(*key as u32, 16).unwrap_or(' ').to_string()
                };

                if index == 3 {
                    return_value += format!("|{}|\n", is_lit).as_str();
                } else {
                    return_value += format!("|{}", is_lit).as_str();
                }
            }
        }

        return_value
    }
}

impl Keypad {
    pub fn push_key(&mut self, key_index: u8) {
        self.keys[key_index as usize] = true;
    }

    pub fn release_key(&mut self, key_index: u8) {
        self.keys[key_index as usize] = false;
    }

    pub fn key_state(&self, key_index: u8) -> bool {
        self.keys[key_index as usize]
    }

    pub fn new() -> Keypad {
        Keypad::default()
    }

    pub fn pressed(&self, key: u8) -> bool {
        self.key_state(key)
    }
    pub fn released(&self, key: u8) -> bool {
        !self.key_state(key)
    }
}