an attempt at doing... something? back in 2015

NumberEncode.php

<?php
/*
 * Phone Numberpad Encoding
 * Provided to you by Flashwave
 *
 * Pretty much what this does is encode (and decode) strings into other strings (wow technology)
 *  that consist out of 1-9, # and *.
 * This is not really supposed to be anything serious, just something I'm doing out of boredom.
 *
 * The goal of this is to be able to encode anything and still be able to decode it properly.
 *
 * Version 1 reference
 * [1: ]        [2: ABC]    [3: DEF]
 * [4: GHI]     [5: JKL]    [6: MNO]
 * [7: PQRS]    [8: TUV]    [9: WXYZ]
 * [*: -]       [0:  ]      [#: +]
 *
 * Version 1 examples
 * 2* 2 2#		= A B C
 * # 2 2# 2##	= A B C
 * 1			= 
 * 1# 2 3 4		= 1 2 3
 * 2 3 4		= B E H
 * 7			= 
 * 7#			= R
 * 7## 4		= S H
 * ## 7	4		= S J
 */

namespace Flashwave;

class NumberEncode {
    
    // Array with types
    protected static $nums = array(
    
        '1'     => '',
        '2*'    => 'A',
        '2'     => 'B',
        '2#'    => 'C',
        '3*'    => 'D',
        '3'     => 'E',
        '3#'    => 'F',
        '4*'    => 'G',
        '4'     => 'H',
        '4#'    => 'I',
        '5*'    => 'J',
        '5'     => 'K',
        '5#'    => 'L',
        '6*'    => 'M',
        '6'     => 'N',
        '6#'    => 'O',
        '7**'   => 'P',
        '7*'    => 'Q',
        '7'     => '',
        '7#'    => 'R',
        '7##'   => 'S',
        '8*'    => 'T',
        '8'     => 'U',
        '8#'    => 'V',
        '9**'   => 'W',
        '9*'    => 'X',
        '9'     => '',
        '9#'    => 'Y',
        '9##'   => 'Z',
        '0'     => ' '
        
    );
    
    protected static $special = array(
    
        '1**'   => '.',
        '1*'    => ',',
        '1#'    => '@',
        '2*'    => '€',
        '2'     => '$',
        '2#'    => '£',
        '3*'    => '%',
        '3'     => '^',
        '3#'    => '&',
        '4*'    => '*',
        '4'     => '(',
        '4#'    => ')',
        '5*'    => '[',
        '5'     => ']',
        '5#'    => '{',
        '6*'    => '}',
        '6'     => '-',
        '6#'    => '\\',
        '7**'   => '!',
        '7*'    => ';',
        '7#'    => '\'',
        '7##'   => '"',
        '8*'    => '?',
        '8'     => '/',
        '8#'    => '<',
        '9**'   => '>',
        '9*'    => '¥',
        '9#'    => '_',
        '9##'   => '~',
        '0*'    => '=',
        '0'     => '|',
        '0#'    => ':'
    
    );
    
    // Encoder
    public static function encode($string) {
        
        // Split each character up into an array
        $array = str_split($string);
        
        // Reset the string variable
        $string = '';
        
        // Iterate over the characters and generate the new string
        foreach($array as $char) {
            if(is_numeric($char)) // Append a 1 for numeric characters and don't do anything special
                $string .= '1'. $char;
            elseif(in_array($char, self::$special)) // Append a 9 for special characters and use the special operator on getChar
                $string .= '9'. self::getChar($char, true, false, true);
            elseif(ctype_upper($char)) // Append a 7 for uppercase characters and parse like normal
                $string .= '7'. self::getChar($char, true);
            else // Just parse and don't do anything else
                $string .= self::getChar($char, true);
        }
        
        // Return the string
        return $string;
        
    }
    
    // Decoder
    public static function decode($string) {
        
        // Split each character up into an array
        $array = str_split($string);
        
        // Reset the string variable
        $string = '';
        
        // Complicated foreach action, preg_match_all was a bitch
        // But in the end this was a better solution anyway
        foreach($array as $key => $char) {
            
            // Skip if the char is a modifier
            if(
                // Filter standalone #
                $char == '#' ||
                // Filter standalone *
                $char == '*' ||
                // Filter NUM prefix
                (
                    $char == '1' &&
                    (
                        isset($array[$key + 1]) &&
                        is_numeric($array[$key + 1]) &&
                        $array[$key + 1] != '1'
                    )
                ) ||
                // Filter CAP prefix
                (
                    $char == '7' &&
                    (
                        isset($array[$key + 1]) &&
                        is_numeric($array[$key + 1]) &&
                        $array[$key + 1] != '7'
                    )
                ) ||
                // Filter SPECIAL prefix
                (
                    $char == '9' &&
                    (
                        isset($array[$key + 1]) &&
                        is_numeric($array[$key + 1]) &&
                        $array[$key + 1] != '9'
                    )
                )
            ) continue;
            
            // Get the correct character
            $string .= ( 
                (
                    ( // Just output the number if the leading number is a 1
                        isset($array[$key - 1]) &&
                        $array[$key - 1] == '1'
                    )
                ) ?
                $char :
                self::getChar(
                    $char
                    .(
                        ( // If the next character is a modifier do modifications
                            array_key_exists($key + 1, $array) &&
                            (
                                $array[$key + 1] == '#' ||
                                $array[$key + 1] == '*'
                            )
                        ) ?
                        $array[$key + 1]
                        .(
                            ( // Do even more if the character after that is a modifier too
                                array_key_exists($key + 2, $array) &&
                                (
                                    $array[$key + 2] == '#' ||
                                    $array[$key + 2] == '*'
                                )
                            ) ?
                            $array[$key + 2] :
                            ''
                        ) :
                        ''
                    ),
                    false, // False for decoding
                    ( // Caps
                        isset($array[$key - 1]) &&
                        $array[$key - 1] == '7'
                    ),
                    ( // Special
                        isset($array[$key - 1]) &&
                        $array[$key - 1] == '9'
                    )
                )
            );

        }

        // Return the string
        return $string;
        
    }
    
    // Get the special character
    public static function getChar($char, $type = false, $caps = false, $special = false) {
        
        // Get a copy of the nums or special array depending on the $special option
        $nums = $special ? self::$special : self::$nums;
        
        // If $caps or $type = true, uppercase the character
        if($caps || $type)
            $char = strtoupper($char);
        
        // If $type = true file the array
        if($type)
            $nums = array_flip($nums);
        
        // If the character exists set $char to it
        if(array_key_exists($char, $nums))
            $char = ($caps ? $nums[$char] : strtolower($nums[$char]));
        else // Otherwise just sort of output a 0
            $char = $type ? '0' : '';
        
        return $char;
        
    }
    
}