LS String PHP lib added

To compress and decompress strings with LZ compression

LZCompressor/LZUtil.php

@@ -0,0 +1,112 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: sics
+ * Date: 27.02.2016
+ * Time: 15:54
+ */
+
+namespace LZCompressor;
+
+
+class LZUtil
+{
+    /**
+    * @var string
+    */
+    public static $keyStrBase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
+    public static $keyStrUriSafe = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-$";
+    private static $baseReverseDic = [];
+
+    /**
+     * @param string $alphabet
+     * @param integer $character
+     * @return string
+     */
+    public static function getBaseValue($alphabet, $character)
+    {
+        if(!array_key_exists($alphabet, self::$baseReverseDic)) {
+            self::$baseReverseDic[$alphabet] = [];
+            for($i=0; $i<strlen($alphabet); $i++) {
+                self::$baseReverseDic[$alphabet][$alphabet{$i}] = $i;
+            }
+        }
+        return self::$baseReverseDic[$alphabet][$character];
+    }
+
+    /**
+     * @return string
+     */
+    public static function fromCharCode()
+    {
+        return array_reduce(func_get_args(), function ($a, $b) {
+            $a .= self::utf8_chr($b);
+            return $a;
+        });
+    }
+
+    /**
+     * Phps chr() equivalent for UTF-8 encoding
+     *
+     * @param int|string $u
+     * @return string
+     */
+    public static function utf8_chr($u)
+    {
+        return mb_convert_encoding('&#' . intval($u) . ';', 'UTF-8', 'HTML-ENTITIES');
+    }
+
+    /**
+     * @param string $str
+     * @param int $num
+     *
+     * @return bool|integer
+     */
+    public static function charCodeAt($str, $num=0)
+    {
+        return self::utf8_ord(self::utf8_charAt($str, $num));
+    }
+
+    /**
+     * @param string $ch
+     *
+     * @return bool|integer
+     */
+    public static function utf8_ord($ch)
+    {
+        // must remain php's strlen
+        $len = strlen($ch);
+        if ($len <= 0) {
+            return -1;
+        }
+        $h = ord($ch{0});
+        if ($h <= 0x7F) return $h;
+        if ($h < 0xC2) return -3;
+        if ($h <= 0xDF && $len > 1) return ($h & 0x1F) << 6 | (ord($ch{1}) & 0x3F);
+        if ($h <= 0xEF && $len > 2) return ($h & 0x0F) << 12 | (ord($ch{1}) & 0x3F) << 6 | (ord($ch{2}) & 0x3F);
+        if ($h <= 0xF4 && $len > 3)
+            return ($h & 0x0F) << 18 | (ord($ch{1}) & 0x3F) << 12 | (ord($ch{2}) & 0x3F) << 6 | (ord($ch{3}) & 0x3F);
+        return -2;
+    }
+
+    /**
+     * @param string $str
+     * @param integer $num
+     *
+     * @return string
+     */
+    public static function utf8_charAt($str, $num)
+    {
+        return mb_substr($str, $num, 1, 'UTF-8');
+    }
+
+    /**
+     * @param string $str
+     * @return integer
+     */
+    public static function utf8_strlen($str) {
+        return mb_strlen($str, 'UTF-8');
+    }
+
+
+}