<?php

/**
 * Kunena Component
 *
 * @package       Kunena.Framework
 * @subpackage    Collection
 *
 * @copyright     Copyright (C) 2008 - @currentyear@ Kunena Team. All rights reserved.
 * @license       https://www.gnu.org/copyleft/gpl.html GNU/GPL
 * @link          https://www.kunena.org
 **/

namespace Kunena\Forum\Libraries\Collection;

use ArrayAccess;
use ArrayIterator;
use Closure;
use Countable;
use IteratorAggregate;

\defined('_JEXEC') or die();

/**
 * Kunena Item Collection.
 *
 * @since   Kunena 6.0
 */
class KunenaCollection implements ArrayAccess, Countable, IteratorAggregate
{
    /**
     * The items in the collection.
     *
     * @var     array
     * @since   Kunena 6.0
     */
    protected $items = [];

    /**
     * Create a new collection.
     *
     * @param   array  $items  Initial items to be added into the collection.
     *
     * @since   Kunena 6.0
     */
    public function __construct(array $items = [])
    {
        $this->items = $items;
    }

    /**
     * Get all items in the collection.
     *
     * @return  array
     *
     * @since   Kunena 6.0
     */
    public function all(): array
    {
        return $this->items;
    }

    /**
     * Get the first item from the collection.
     *
     * @return  mixed|null
     *
     * @since   Kunena 6.0
     */
    public function first()
    {
        return !empty($this->items) ? reset($this->items) : null;
    }

    /**
     * Get the last item from the collection.
     *
     * @return  mixed|null
     *
     * @since   Kunena 6.0
     */
    public function last()
    {
        return !empty($this->items) ? end($this->items) : null;
    }

    /**
     * Run a filter over each of the items.
     *
     * @param   Closure  $callback  callback
     *
     * @return  KunenaCollection
     *
     * @since   Kunena 6.0
     */
    public function filter(Closure $callback): KunenaCollection
    {
        return new static(array_filter($this->items, $callback));
    }

    /**
     * Execute a callback over each item.
     *
     * @param   Closure  $callback  callback
     *
     * @return  KunenaCollection
     *
     * @since   Kunena 6.0
     */
    public function each(Closure $callback): KunenaCollection
    {
        array_map($callback, $this->items);

        return $this;
    }

    /**
     * Run a map over each of the items.
     *
     * @param   Closure  $callback  callback
     *
     * @return  KunenaCollection
     *
     * @since   Kunena 6.0
     */
    public function map(Closure $callback): KunenaCollection
    {
        return new static(array_map($callback, $this->items, array_keys($this->items)));
    }

    /**
     * Get an iterator for the items.
     *
     * @return  arrayIterator
     *
     * @since   Kunena 6.0
     */
    public function getIterator(): ArrayIterator
    {
        return new ArrayIterator($this->items);
    }

    /**
     * Count the number of items in the collection.
     *
     * @return  integer
     *
     * @since   Kunena 6.0
     */
    public function count(): int
    {
        return \count($this->items);
    }

    /**
     * Determine if an item exists at an offset.
     *
     * @param   mixed  $key  key
     *
     * @return  boolean
     *
     * @since   Kunena 6.0
     */
    public function offsetExists($key): bool
    {
        return \array_key_exists($key, $this->items);
    }

    /**
     * Get an item at a given offset.
     *
     * @param   mixed  $key  key
     *
     * @return  mixed
     *
     * @since   Kunena 6.0
     */
    #[\ReturnTypeWillChange]
    public function offsetGet($key)
    {
        return $this->items[$key];
    }

    /**
     * Set the item at a given offset.
     *
     * @param   mixed  $key    key
     * @param   mixed  $value  value
     *
     * @return  void
     *
     * @since   Kunena 6.0
     */
    #[\ReturnTypeWillChange]
    public function offsetSet($key, $value)
    {
        if (\is_null($key)) {
            $this->items[] = $value;
        } else {
            $this->items[$key] = $value;
        }
    }

    /**
     * Unset the item at a given offset.
     *
     * @param   string  $key  key
     *
     * @return  void
     *
     * @since   Kunena 6.0
     */
    #[\ReturnTypeWillChange]
    public function offsetUnset($key)
    {
        unset($this->items[$key]);
    }
}