<?php

namespace Box\Spout\Reader\CSV;

use Box\Spout\Reader\IteratorInterface;

/**
 * Class SheetIterator
 * Iterate over CSV unique "sheet".
 *
 * @package Box\Spout\Reader\CSV
 */
class SheetIterator implements IteratorInterface {

	/** @var \Box\Spout\Reader\CSV\Sheet The CSV unique "sheet" */
	protected $sheet;

	/** @var bool Whether the unique "sheet" has already been read */
	protected $hasReadUniqueSheet = false;

	/**
	 * @param resource $filePointer
	 * @param \Box\Spout\Reader\CSV\ReaderOptions $options
	 * @param \Box\Spout\Common\Helper\GlobalFunctionsHelper $globalFunctionsHelper
	 */
	public function __construct( $filePointer, $options, $globalFunctionsHelper ) {
		 $this->sheet = new Sheet( $filePointer, $options, $globalFunctionsHelper );
	}

	/**
	 * Rewind the Iterator to the first element
	 * @link http://php.net/manual/en/iterator.rewind.php
	 *
	 * @return void
	 */
	public function rewind() {
		$this->hasReadUniqueSheet = false;
	}

	/**
	 * Checks if current position is valid
	 * @link http://php.net/manual/en/iterator.valid.php
	 *
	 * @return bool
	 */
	public function valid() {
		return ( ! $this->hasReadUniqueSheet );
	}

	/**
	 * Move forward to next element
	 * @link http://php.net/manual/en/iterator.next.php
	 *
	 * @return void
	 */
	public function next() {
		$this->hasReadUniqueSheet = true;
	}

	/**
	 * Return the current element
	 * @link http://php.net/manual/en/iterator.current.php
	 *
	 * @return \Box\Spout\Reader\CSV\Sheet
	 */
	public function current() {
		 return $this->sheet;
	}

	/**
	 * Return the key of the current element
	 * @link http://php.net/manual/en/iterator.key.php
	 *
	 * @return int
	 */
	public function key() {
		 return 1;
	}

	/**
	 * Cleans up what was created to iterate over the object.
	 *
	 * @return void
	 */
	public function end() {
		 // do nothing
	}
}