Merge pull request #100 from mambax7/feature/ulid

Author: mambax7

src/Ulid.php

@@ -0,0 +1,193 @@
+<?php
+/*
+ You may not change or alter any portion of this comment or credits
+ of supporting developers from this source code or any supporting source code
+ which is considered copyrighted (c) material of the original comment or credit authors.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace Xmf;
+
+/**
+ * Generate ULID
+ *
+ * @category  Xmf\Ulid
+ * @package   Xmf
+ * @author    Michael Beck <mambax7@gmail.com>
+ * @copyright 2023 XOOPS Project (https://xoops.org)
+ * @license   GNU GPL 2 or later (https://www.gnu.org/licenses/gpl-2.0.html)
+ */
+class Ulid
+{
+    const ENCODING_CHARS = '0123456789ABCDEFGHJKMNPQRSTVWXYZ';
+    const ENCODING_LENGTH = 32;
+
+    /**
+     * Generate a new ULID.
+     *
+     * @return string The generated ULID.
+     */
+    public static function generate(bool $upperCase = true): string
+    {
+        $time = self::microtimeToUlidTime(\microtime(true));
+        $timeChars = self::encodeTime($time);
+        $randChars = self::encodeRandomness();
+        $ulid      = $timeChars . $randChars;
+
+        $ulid = $upperCase ? \strtoupper($ulid) : \strtolower($ulid);
+
+        return $ulid;
+    }
+
+    /**
+     * @param int $time
+     *
+     * @return string
+     */
+    public static function encodeTime(int $time): string
+    {
+        $encodingCharsArray = str_split(self::ENCODING_CHARS);
+        $timeChars = '';
+        for ($i = 0; $i < 10; $i++) {
+            $mod = \floor($time % self::ENCODING_LENGTH);
+            $timeChars = $encodingCharsArray[$mod] . $timeChars;
+            $time = (int)(($time - $mod) / self::ENCODING_LENGTH);
+        }
+        return $timeChars;
+    }
+
+    public static function encodeRandomness(): string
+    {
+        $encodingCharsArray = str_split(self::ENCODING_CHARS);
+        $randomBytes = \random_bytes(10); // 80 bits
+        // Check if the random bytes were generated successfully.
+        if (false === $randomBytes) {
+            throw new \RuntimeException('Failed to generate random bytes');
+        }
+
+        $randChars   = '';
+        for ($i = 0; $i < 16; $i++) {
+            $randValue = \ord($randomBytes[$i % 10]);
+            if (0 === $i % 2) {
+                $randValue >>= 3; // take the upper 5 bits
+            } else {
+                $randValue &= 31; // take the lower 5 bits
+            }
+            $randChars .= $encodingCharsArray[$randValue];
+        }
+        return $randChars;
+    }
+
+    /**
+     * @param string $ulid
+     *
+     * @return array
+     */
+    public static function decode(string $ulid): array
+    {
+        if (!self::isValid($ulid)) {
+            throw new \InvalidArgumentException('Invalid ULID string');
+        }
+
+        $time = self::decodeTime($ulid);
+        $rand = self::decodeRandomness($ulid);
+
+        return [
+            'time' => $time,
+            'rand' => $rand,
+        ];
+    }
+
+    /**
+     * @param string $ulid
+     *
+     * @return int
+     */
+    public static function decodeTime(string $ulid): int
+    {
+//        $encodingCharsArray = str_split(self::ENCODING_CHARS);
+
+        // Check if the ULID string is valid.
+        if (!self::isValid($ulid)) {
+            throw new \InvalidArgumentException('Invalid ULID string');
+        }
+
+        $time = 0;
+        for ($i = 0; $i < 10; $i++) {
+            $char = $ulid[$i];
+            $value = \strpos(self::ENCODING_CHARS, $char);
+            $exponent = 9 - $i;
+            $time += $value * \bcpow((string)self::ENCODING_LENGTH, (string)$exponent);
+        }
+
+        return $time;
+    }
+
+    /**
+     * @param string $ulid
+     *
+     * @return int
+     */
+    public static function decodeRandomness(string $ulid): int
+    {
+        if (26 !== strlen($ulid)) {
+            throw new \InvalidArgumentException('Invalid ULID length');  // Changed line
+        }
+
+        $rand = 0;
+        for ($i = 10; $i < 26; $i++) {
+            $char = $ulid[$i];
+            $value = \strpos(self::ENCODING_CHARS, $char);
+
+            // Check if the random value is within the valid range.
+            if ($value < 0 || $value >= self::ENCODING_LENGTH) {
+                throw new \InvalidArgumentException('Invalid ULID random value');
+            }
+            $exponent = 15 - $i;
+            $rand += $value * \bcpow((string)self::ENCODING_LENGTH, (string)$exponent);
+        }
+
+        return $rand;
+    }
+
+    /**
+     * @param string $ulid
+     *
+     * @return bool
+     */
+    public static function isValid(string $ulid): bool
+    {
+        // Check the length of the ULID string before throwing an exception.
+        if (26 !== strlen($ulid)) {
+            return false;
+        }
+
+        // Throw an exception if the ULID is invalid.
+        try {
+            self::decodeRandomness($ulid);
+        } catch (\InvalidArgumentException $e) {
+                return false;
+}
+
+        return true;
+    }
+
+    /**
+     * @param float $microtime
+     *
+     * @return int
+     */
+    public static function microtimeToUlidTime(float $microtime): int
+    {
+        $timestamp = $microtime * 1000000;
+        $unixEpoch = 946684800000000; // Microseconds since the Unix epoch.
+
+        return (int)($timestamp - $unixEpoch);
+    }
+}
+
+
+