1 files changed, 153 insertions, 0 deletions
diff --git a/vendor/patrickschur/language-detection/src/LanguageDetection/NgramParser.php b/vendor/patrickschur/language-detection/src/LanguageDetection/NgramParser.php
new file mode 100644
index 000000000..8b69241eb
--- /dev/null
+++ b/vendor/patrickschur/language-detection/src/LanguageDetection/NgramParser.php
@@ -0,0 +1,153 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace LanguageDetection;
+
+use LanguageDetection\Tokenizer\TokenizerInterface;
+use LanguageDetection\Tokenizer\WhitespaceTokenizer;
+
+/**
+ * Class NgramParser
+ *
+ * @copyright Patrick Schur
+ * @license https://opensource.org/licenses/mit-license.html MIT
+ * @author Patrick Schur <patrick_schur@outlook.de>
+ * @package LanguageDetection
+ */
+abstract class NgramParser
+{
+    /**
+     * @var int
+     */
+    protected $minLength = 1;
+
+    /**
+     * @var int
+     */
+    protected $maxLength = 3;
+
+    /**
+     * @var int
+     */
+    protected $maxNgrams = 310;
+
+    /**
+     * @var TokenizerInterface
+     */
+    protected $tokenizer = null;
+
+    /**
+     * @param int $minLength
+     * @throws \LengthException
+     */
+    public function setMinLength(int $minLength)
+    {
+        if ($minLength <= 0 || $minLength >= $this->maxLength)
+        {
+            throw new \LengthException('$minLength must be greater than zero and less than $this->maxLength.');
+        }
+
+        $this->minLength = $minLength;
+    }
+
+    /**
+     * @param int $maxLength
+     * @throws \LengthException
+     */
+    public function setMaxLength(int $maxLength)
+    {
+        if ($maxLength <= $this->minLength)
+        {
+            throw new \LengthException('$maxLength must be greater than $this->minLength.');
+        }
+
+        $this->maxLength = $maxLength;
+    }
+
+    /**
+     * @param int $maxNgrams
+     * @throws \LengthException
+     */
+    public function setMaxNgrams(int $maxNgrams)
+    {
+        if ($maxNgrams <= 0)
+        {
+            throw new \LengthException('$maxNgrams must be greater than zero.');
+        }
+
+        $this->maxNgrams = $maxNgrams;
+    }
+
+    /**
+     * Sets the tokenizer
+     *
+     * @param TokenizerInterface $tokenizer
+     */
+    public function setTokenizer(TokenizerInterface $tokenizer)
+    {
+        $this->tokenizer = $tokenizer;
+    }
+
+    /**
+     * @param string $str
+     * @return array
+     */
+    private function tokenize(string $str)
+    {
+        if (null === $this->tokenizer)
+        {
+            $this->tokenizer = new WhitespaceTokenizer();
+        }
+
+        return $this->tokenizer->tokenize($str);
+    }
+
+    /**
+     * @param string $str
+     * @return array
+     */
+    protected function getNgrams(string $str): array
+    {
+        $tokens = [];
+
+        foreach ($this->tokenize($str) as $word)
+        {
+            $l = \mb_strlen($word);
+
+            for ($i = $this->minLength; $i <= $this->maxLength; ++$i)
+            {
+                for ($j = 0; ($i + $j - 1) < $l; ++$j, ++$tmp)
+                {
+                    $tmp = &$tokens[$i][\mb_substr($word, $j, $i)];
+                }
+            }
+        }
+
+        foreach ($tokens as $i => $token)
+        {
+            $sum = \array_sum($token);
+
+            foreach ($token as $j => $value)
+            {
+                $tokens[$i][$j] = $value / $sum;
+            }
+        }
+
+        if (!\count($tokens))
+        {
+            return [];
+        }
+
+        $tokens = \array_merge(...$tokens);
+        unset($tokens['_']);
+
+        \arsort($tokens, SORT_NUMERIC);
+
+        return \array_slice(
+            \array_keys($tokens),
+            0,
+            $this->maxNgrams
+        );
+    }
+}