<?php
/**
 * Represents a new HashMap.
 *
 * @author Vendetta <admin@vendetta-media.nl>
 * @copyright (c) 2011 Vendetta Media
 */
class HashMap {

    /**
     * Associative array that contains the data of this hashmap.
     *
     * @var Array
     */
    protected $data;

    /**
     * The current index in the array.
     *
     * @var int
     */
    protected $offset = 0;

    /**
     * Constructs a new HashMap.
     */
    public function __construct() {

    }

    /**
     * Adds a new value to the HashMap.
     *
     * @param Mixed $key
     * @param Mixed $value
     */
    public function put($key, $value) {
        if (is_numeric($key)) {
            $this->data[] = $value;
        } else {
            $this->data[$key] = $value;
        }
        $this->offset++;
    }

    /**
     * Adds a complete array to the HashMap.
     *
     * @param Array $data
     */
    public function putAll(array $data) {
        foreach($data as $key => $value) {
            $this->put($key, $value);
        }
    }

    /**
     * Gets a value from the HashMap.
     * If $key is NULL it will return the item,
     * at the current offset.
     *
     * @param Mixed $key
     * @return Mixed $value
     */
    public function get($key = NULL) {
        return $this->data[(is_null($key) ? $this->offset : $key)];
    }

    /**
     * Removes an element from the array.
     * If the $key is NULL, the element at the current,
     * offset will be deleted.
     *
     * @param Mixed $key
     */
    public function remove($key = NULL) {
        if (is_null($offset)) {
            unset($this->data[$this->offset]);
        } else {
            if (array_key_exists($key, $this->data)) {
                unset($this->data[$key]);
            }
        }
    }

    /**
     * Returns the total length of the HashMap.
     *
     * @return int
     */
    public function size() {
        return (int) count($this->data);
    }

    /**
     * Clears all data from the HashMap,
     * and resets the offset.
     */
    public function clear() {
        $this->data = array();
        $this->offset = 0;
    }

    /**
     * Sets the offset to the next element.
     */
    public function next() {
        $this->offset++;
    }

    /**
     * Sets the offset to the previous element.
     */
    public function previous() {
        $this->offset--;
    }

    /**
     * Reset the offset back to 0.
     */
    public function rewind() {
        $this->offset = 0;
    }

    /**
     * If the param is null, the function will return the,
     * current offset else it will set the current offset.
     *
     * @param Mixed $offset
     * @return int $offset
     * @throws InvalidArgumentException
     */
    public function offset($offset = NULL) {
        if (is_null($offset)) {
            return (int) $this->offset;
        }
        if (!is_numeric($offset)) {
            throw new InvalidArgumentException("$offset must be of type Integer.");
        }
        $this->offset = $offset;
    }

    /**
     * Returns the HashMap as array.
     *
     * @return Array $data
     */
    public function asArray() {
        return (array) $this->data;
    }

    /**
     * Checks if a $key exists or not.
     *
     * @param Mixed $key
     * @return Boolean
     */
    public function containsKey($key) {
        return (boolean) array_key_exists($key);
    }

    /**
     * Checks if a $value exists in the array or not.
     *
     * @param Mixed $value
     * @return Boolean
     */
    public function containsKey($value) {
        return (boolean) in_array($value);
    }

    /**
     * Returns true if the HashMap is empty.
     *
     * @return Boolean
     */
    public function isEmpty() {
        return (boolean) (count($this->data) == 0 ? true : false);
    }
}
?>