remove autoload section in composer.json

[github/wallabag/wallabag.git] / inc / 3rdparty / htmlpurifier / HTMLPurifier / Zipper.php

<?php\r
\r
/**\r
 * A zipper is a purely-functional data structure which contains\r
 * a focus that can be efficiently manipulated.  It is known as\r
 * a "one-hole context".  This mutable variant implements a zipper\r
 * for a list as a pair of two arrays, laid out as follows:\r
 *\r
 *      Base list: 1 2 3 4 [ ] 6 7 8 9\r
 *      Front list: 1 2 3 4\r
 *      Back list: 9 8 7 6\r
 *\r
 * User is expected to keep track of the "current element" and properly\r
 * fill it back in as necessary.  (ToDo: Maybe it's more user friendly\r
 * to implicitly track the current element?)\r
 *\r
 * Nota bene: the current class gets confused if you try to store NULLs\r
 * in the list.\r
 */\r
\r
class HTMLPurifier_Zipper\r
{\r
    public $front, $back;\r
\r
    public function __construct($front, $back) {\r
        $this->front = $front;\r
        $this->back = $back;\r
    }\r
\r
    /**\r
     * Creates a zipper from an array, with a hole in the\r
     * 0-index position.\r
     * @param Array to zipper-ify.\r
     * @return Tuple of zipper and element of first position.\r
     */\r
    static public function fromArray($array) {\r
        $z = new self(array(), array_reverse($array));\r
        $t = $z->delete(); // delete the "dummy hole"\r
        return array($z, $t);\r
    }\r
\r
    /**\r
     * Convert zipper back into a normal array, optionally filling in\r
     * the hole with a value. (Usually you should supply a $t, unless you\r
     * are at the end of the array.)\r
     */\r
    public function toArray($t = NULL) {\r
        $a = $this->front;\r
        if ($t !== NULL) $a[] = $t;\r
        for ($i = count($this->back)-1; $i >= 0; $i--) {\r
            $a[] = $this->back[$i];\r
        }\r
        return $a;\r
    }\r
\r
    /**\r
     * Move hole to the next element.\r
     * @param $t Element to fill hole with\r
     * @return Original contents of new hole.\r
     */\r
    public function next($t) {\r
        if ($t !== NULL) array_push($this->front, $t);\r
        return empty($this->back) ? NULL : array_pop($this->back);\r
    }\r
\r
    /**\r
     * Iterated hole advancement.\r
     * @param $t Element to fill hole with\r
     * @param $i How many forward to advance hole\r
     * @return Original contents of new hole, i away\r
     */\r
    public function advance($t, $n) {\r
        for ($i = 0; $i < $n; $i++) {\r
            $t = $this->next($t);\r
        }\r
        return $t;\r
    }\r
\r
    /**\r
     * Move hole to the previous element\r
     * @param $t Element to fill hole with\r
     * @return Original contents of new hole.\r
     */\r
    public function prev($t) {\r
        if ($t !== NULL) array_push($this->back, $t);\r
        return empty($this->front) ? NULL : array_pop($this->front);\r
    }\r
\r
    /**\r
     * Delete contents of current hole, shifting hole to\r
     * next element.\r
     * @return Original contents of new hole.\r
     */\r
    public function delete() {\r
        return empty($this->back) ? NULL : array_pop($this->back);\r
    }\r
\r
    /**\r
     * Returns true if we are at the end of the list.\r
     * @return bool\r
     */\r
    public function done() {\r
        return empty($this->back);\r
    }\r
\r
    /**\r
     * Insert element before hole.\r
     * @param Element to insert\r
     */\r
    public function insertBefore($t) {\r
        if ($t !== NULL) array_push($this->front, $t);\r
    }\r
\r
    /**\r
     * Insert element after hole.\r
     * @param Element to insert\r
     */\r
    public function insertAfter($t) {\r
        if ($t !== NULL) array_push($this->back, $t);\r
    }\r
\r
    /**\r
     * Splice in multiple elements at hole.  Functional specification\r
     * in terms of array_splice:\r
     *\r
     *      $arr1 = $arr;\r
     *      $old1 = array_splice($arr1, $i, $delete, $replacement);\r
     *\r
     *      list($z, $t) = HTMLPurifier_Zipper::fromArray($arr);\r
     *      $t = $z->advance($t, $i);\r
     *      list($old2, $t) = $z->splice($t, $delete, $replacement);\r
     *      $arr2 = $z->toArray($t);\r
     *\r
     *      assert($old1 === $old2);\r
     *      assert($arr1 === $arr2);\r
     *\r
     * NB: the absolute index location after this operation is\r
     * *unchanged!*\r
     *\r
     * @param Current contents of hole.\r
     */\r
    public function splice($t, $delete, $replacement) {\r
        // delete\r
        $old = array();\r
        $r = $t;\r
        for ($i = $delete; $i > 0; $i--) {\r
            $old[] = $r;\r
            $r = $this->delete();\r
        }\r
        // insert\r
        for ($i = count($replacement)-1; $i >= 0; $i--) {\r
            $this->insertAfter($r);\r
            $r = $replacement[$i];\r
        }\r
        return array($old, $r);\r
    }\r
}\r