bookboon/api-php

<?php

namespace Bookboon\Api\Entity;

use Bookboon\Api\Exception\UsageException;
use Countable;
use Iterator;
use JsonSerializable;

/**
 * Class EntityStore
 * @package Bookboon\Api\Entity
 * @template T extends Entity
 */
class EntityStore implements Iterator, Countable, JsonSerializable
{
    /**
     * @var array<T>
     */
    protected $contents;

    /**
     * @var int
     */
    private $index = 0;

    /**
     * EntityStore constructor.
     * @param array<T> $contents
     * @psalm-param class-string<T> $classString
     */
    public function __construct(array $contents = [], string $className = Entity::class)
    {
        $this->contents = $contents;
    }

    /**
     * @return array<Entity>
     * @psalm-return array<T>
     */
    public function get() : array
    {
        return $this->contents;
    }

    /**
     * @return Entity
     * @psalm-return T
     * @throws UsageException
     */
    public function getSingle() : Entity
    {
        if (count($this->contents) === 1) {
            return $this->contents[0];
        }

        throw new UsageException("Multiple responses exists");
    }

    /**
     * Return the current element
     * @link https://php.net/manual/en/iterator.current.php
     * @return Entity
     * @psalm-return T
     * @since 5.0.0
     */
    public function current()
    {
        return $this->contents[$this->index];
    }

    /**
     * Move forward to next element
     * @link https://php.net/manual/en/iterator.next.php
     * @return void Any returned value is ignored.
     * @since 5.0.0
     */
    public function next()
    {
        $this->index++;
    }

    /**
     * Return the key of the current element
     * @link https://php.net/manual/en/iterator.key.php
     * @return mixed scalar on success, or null on failure.
     * @since 5.0.0
     */
    public function key()
    {
        return $this->index;
    }

    /**
     * Checks if current position is valid
     * @link https://php.net/manual/en/iterator.valid.php
     * @return boolean The return value will be casted to boolean and then evaluated.
     * Returns true on success or false on failure.
     * @since 5.0.0
     */
    public function valid()
    {
        return isset($this->contents[$this->key()]);
    }

    /**
     * Rewind the Iterator to the first element
     * @link https://php.net/manual/en/iterator.rewind.php
     * @return void Any returned value is ignored.
     * @since 5.0.0
     */
    public function rewind()
    {
        $this->index = 0;
    }

    /**
     * Count elements of an object
     * @link https://php.net/manual/en/countable.count.php
     * @return int The custom count as an integer.
     * </p>
     * <p>
     * The return value is cast to an integer.
     * @since 5.1.0
     */
    public function count()
    {
        return count($this->contents);
    }

    /**
     * Specify data which should be serialized to JSON
     * @link https://php.net/manual/en/jsonserializable.jsonserialize.php
     * @return mixed data which can be serialized by <b>json_encode</b>,
     * which is a value of any type other than a resource.
     * @since 5.4.0
     */
    public function jsonSerialize()
    {
        return $this->contents;
    }
}