Huffman encoding implemented

Utils/Encoding/Huffman.php

@@ -1,6 +0,0 @@
-<?php
-
-final class Huffman
-{
-
-}

Utils/Encoding/Huffman/Dictionary.php

@@ -0,0 +1,229 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.0
+ *
+ * @category   TBD
+ * @package    TBD
+ * @author     OMS Development Team <dev@oms.com>
+ * @author     Dennis Eichhorn <d.eichhorn@oms.com>
+ * @copyright  2013 Dennis Eichhorn
+ * @license    OMS License 1.0
+ * @version    1.0.0
+ * @link       http://orange-management.com
+ */
+namespace phpOMS\Utils\Encoding\Huffman;
+
+/**
+ * Gray encoding class
+ *
+ * @category   Framework
+ * @package    phpOMS\Utils
+ * @author     OMS Development Team <dev@oms.com>
+ * @author     Dennis Eichhorn <d.eichhorn@oms.com>
+ * @license    OMS License 1.0
+ * @link       http://orange-management.com
+ * @since      1.0.0
+ */
+final class Dictionary
+{
+    /**
+     * Huffman dictionary.
+     *
+     * @var array
+     * @since 1.0.0
+     */
+    private $dictionary = [];
+
+    /**
+     * Minimum length.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    private $min = -1;
+
+    /**
+     * Maximum length.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    private $max = -1;
+
+    /**
+     * Constructor.
+     *
+     * @param string $source Source to create the dictionary from
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function __construct(string $source = '')
+    {
+        if (isset($source)) {
+            $this->generate($source);
+        }
+    }
+
+    /**
+     * Get dictionary value by entry
+     *
+     * @param string $entry 1 character entry
+     *
+     * @return string
+     *
+     * @throws
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function get(string $entry) : string
+    {
+        if (strlen($entry) !== 1) {
+            throw new \Exception('Must be a character.');
+        }
+
+        if (!isset($this->dictionary[$entry])) {
+            throw new \Exception('Character does not exist');
+        }
+
+        return $this->dictionary[$entry];
+    }
+
+    /**
+     * Get dictionary entry and reduce value
+     *
+     * @param string $value Dictionary value
+     *
+     * @return null|string
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function getEntry(&$value)
+    {
+        $length = strlen($value);
+        if ($length < $this->min) {
+            return null;
+        }
+
+        for ($i = $this->min; $i <= $this->max; ++$i) {
+            $needle = substr($value, 0, $i);
+
+            foreach ($this->dictionary as $key => $val) {
+                if ($needle === $val) {
+                    $value = substr($value, $i);
+
+                    return $key;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Set dictionary value
+     *
+     * @param string $entry 1 character entry
+     * @param string $value Dictionary value
+     *
+     * @return void
+     *
+     * @throws
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function set(string $entry, string $value)
+    {
+        if (strlen($entry) !== 1) {
+            throw new \Exception('Must be a character.');
+        }
+
+        if (!isset($this->dictionary[$entry])) {
+            throw new \Exception('Character does not exist');
+        }
+
+        if (strlen(str_replace('0', '', str_replace('1', '', $value))) !== 0) {
+            throw new \Exception('Bad formatting.');
+        }
+
+        $length = strlen($value);
+
+        if ($this->min === -1 || $length < $this->min) {
+            $this->min = $length;
+        }
+
+        if ($this->max === -1 || $length > $this->max) {
+            $this->max = $length;
+        }
+
+        $this->dictionary[$entry] = $value;
+    }
+
+    /**
+     * Generate dictionary from data.
+     *
+     * @param string $source Source data to generate dictionary from
+     *
+     * @return void
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function generate(string $source)
+    {
+        $this->dictionary = [];
+        $this->min        = -1;
+        $this->max        = -1;
+
+        $count = [];
+        while (isset($source[0])) {
+            $count[] = [substr_count($source, $source[0]), $source[0]];
+            $source  = str_replace($source[0], '', $source);
+        }
+
+        sort($count);
+
+        while (count($count) > 1) {
+            $row1    = array_shift($count);
+            $row2    = array_shift($count);
+            $count[] = [$row1[0] + $row2[0], [$row1, $row2]];
+
+            sort($count);
+        }
+
+        $this->fill(is_array($count[0][1]) ? $count[0][1] : $count);
+    }
+
+    /**
+     * Fill dictionary.
+     *
+     * @param string $entry Source data to generate dictionary from
+     * @param string $value Dictionary value
+     *
+     * @return void
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    private function fill(string $entry, string $value = '')
+    {
+        if (!is_array($entry[0][1])) {
+            $this->set($entry[0][1], $value . '0');
+        } else {
+            $this->fill($entry[0][1], $value . '0');
+        }
+
+        if (isset($entry[1])) {
+            if (!is_array($entry[1][1])) {
+                $this->set($entry[1][1], $value . '1');
+            } else {
+                $this->fill($entry[1][1], $value . '1');
+            }
+        }
+    }
+}

Utils/Encoding/Huffman/Huffman.php

@@ -0,0 +1,159 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.0
+ *
+ * @category   TBD
+ * @package    TBD
+ * @author     OMS Development Team <dev@oms.com>
+ * @author     Dennis Eichhorn <d.eichhorn@oms.com>
+ * @copyright  2013 Dennis Eichhorn
+ * @license    OMS License 1.0
+ * @version    1.0.0
+ * @link       http://orange-management.com
+ */
+namespace phpOMS\Utils\Encoding\Huffman;
+
+/**
+ * Gray encoding class
+ *
+ * @category   Framework
+ * @package    phpOMS\Utils
+ * @author     OMS Development Team <dev@oms.com>
+ * @author     Dennis Eichhorn <d.eichhorn@oms.com>
+ * @license    OMS License 1.0
+ * @link       http://orange-management.com
+ * @since      1.0.0
+ */
+final class Huffman
+{
+    /**
+     * Huffman dictionary.
+     *
+     * @var Dictionary
+     * @since 1.0.0
+     */
+    private $dictionary = null;
+
+    /**
+     * Set dictionary
+     *
+     * @param Dictionary $dictionary Huffman dictionary
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function setDictionary(Dictionary $dictionary)
+    {
+        $this->dictionary = $dictionary;
+    }
+
+    /**
+     * Remove dictionary
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function removeDictionary()
+    {
+        $this->dictionary = null;
+    }
+
+    /**
+     * Get dictionary
+     *
+     * @return Dictionary
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function getDictionary() : Dictionary
+    {
+        return $this->dictionary;
+    }
+
+    /**
+     * Encode.
+     *
+     * @param string $source Source to encode
+     *
+     * @return string
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function encode(string $source) : string
+    {
+        if (empty($source)) {
+            return '';
+        }
+
+        if (!isset($this->dictionary)) {
+            $this->dictionary = new Dictionary($source);
+        }
+
+        $binary = '';
+        for ($i = 0; isset($source[$i]); ++$i) {
+            $binary .= $this->dictionary->get($source[$i]);
+        }
+
+        $splittedBinaryString = str_split('1' . $binary . '1', 8);
+        $binary               = '';
+
+        foreach ($splittedBinaryString as $i => $c) {
+            while (strlen($c) < 8) {
+                $c .= '0';
+            }
+
+            $binary .= chr(bindec($c));
+        }
+
+        return $binary;
+    }
+
+    /**
+     * Decode.
+     *
+     * @param string $raw Raw to decode
+     *
+     * @return string
+     *
+     * @since  1.0.0
+     * @author Dennis Eichhorn <d.eichhorn@oms.com>
+     */
+    public function decode(string $raw) : string
+    {
+        if (empty($raw)) {
+            return '';
+        }
+
+        $binary    = '';
+        $rawLenght = strlen($raw);
+        $source    = '';
+
+        for ($i = 0; $i < $rawLenght; ++$i) {
+            $decbin = decbin(ord($raw[$i]));
+
+            while (strlen($decbin) < 8) {
+                $decbin = '0' . $decbin;
+            }
+
+            if ($i === 0) {
+                $decbin = substr($decbin, strpos($decbin, '1') + 1);
+            }
+
+            if ($i + 1 === $rawLenght) {
+                $decbin = substr($decbin, 0, strrpos($decbin, '1'));
+            }
+
+            $binary .= $decbin;
+
+            while (($entry = $this->dictionary->getEntry($binary)) !== null) {
+                $source .= $entry;
+            }
+        }
+
+        return $source;
+    }
+}