<?php

namespace App\Vnc;

use JumPHP\Gui\Pointer;

/** X11 keysyms of the keys (what RFB's KeyEvent carries). */
final class Keysym
{
    public const BACKSPACE = 0xff08;
    public const TAB = 0xff09;
    public const RETURN = 0xff0d;
    public const ESCAPE = 0xff1b;
    public const DELETE = 0xffff;
    public const HOME = 0xff50;
    public const LEFT = 0xff51;
    public const UP = 0xff52;
    public const RIGHT = 0xff53;
    public const DOWN = 0xff54;
    public const PAGEUP = 0xff55;
    public const PAGEDOWN = 0xff56;
    public const END = 0xff57;
    public const INSERT = 0xff63;
    public const F1 = 0xffbe;
    public const SHIFT = 0xffe1;
    public const CONTROL = 0xffe3;
    public const ALT = 0xffe9;

    /** SDL key code -> keysym, for the keys that type no character. */
    public static function special(int $sdl): ?int
    {
        if ($sdl >= 1073741882 && $sdl <= 1073741893) {
            return self::F1 + ($sdl - 1073741882);        // F1..F12
        }
        return match ($sdl) {
            Pointer::BACKSPACE => self::BACKSPACE,
            Pointer::TAB => self::TAB,
            Pointer::RETURN, Pointer::KP_ENTER => self::RETURN,
            Pointer::ESCAPE => self::ESCAPE,
            Pointer::DELETE => self::DELETE,
            Pointer::HOME => self::HOME,
            Pointer::END => self::END,
            Pointer::LEFT => self::LEFT,
            Pointer::RIGHT => self::RIGHT,
            Pointer::UP => self::UP,
            Pointer::DOWN => self::DOWN,
            Pointer::PAGEUP => self::PAGEUP,
            Pointer::PAGEDOWN => self::PAGEDOWN,
            1073741897 => self::INSERT,
            default => null,
        };
    }

    /** A typed character -> keysym (Latin-1 as is, other letters 0x01000000 + their code point). */
    public static function char(string $char): int
    {
        $code = mb_ord($char, 'UTF-8');
        if ($code === false) {
            return 0;
        }
        return $code < 0x100 ? $code : 0x01000000 + $code;
    }
}