<?php

namespace Box\Spout\Writer\CSV;

use Box\Spout\Writer\AbstractWriter;
use Box\Spout\Common\Exception\IOException;
use Box\Spout\Common\Helper\EncodingHelper;

/**
 * Class Writer
 * This class provides support to write data to CSV files
 *
 * @package Box\Spout\Writer\CSV
 */
class Writer extends AbstractWriter {

	/** Number of rows to write before flushing */
	const FLUSH_THRESHOLD = 500;

	/** @var string Content-Type value for the header */
	protected static $headerContentType = 'text/csv; charset=UTF-8';

	/** @var string Defines the character used to delimit fields (one character only) */
	protected $fieldDelimiter = ',';

	/** @var string Defines the character used to enclose fields (one character only) */
	protected $fieldEnclosure = '"';

	/** @var int */
	protected $lastWrittenRowIndex = 0;

	/** @var bool */
	protected $shouldAddBOM = true;

	/**
	 * Sets the field delimiter for the CSV
	 *
	 * @api
	 * @param string $fieldDelimiter Character that delimits fields
	 * @return Writer
	 */
	public function setFieldDelimiter( $fieldDelimiter ) {
		$this->fieldDelimiter = $fieldDelimiter;
		return $this;
	}

	/**
	 * Sets the field enclosure for the CSV
	 *
	 * @api
	 * @param string $fieldEnclosure Character that enclose fields
	 * @return Writer
	 */
	public function setFieldEnclosure( $fieldEnclosure ) {
		$this->fieldEnclosure = $fieldEnclosure;
		return $this;
	}

	/**
	 * Set if a BOM has to be added to the file
	 *
	 * @param bool $shouldAddBOM
	 * @return Writer
	 */
	public function setShouldAddBOM( $shouldAddBOM ) {
		$this->shouldAddBOM = (bool) $shouldAddBOM;
		return $this;
	}

	/**
	 * Opens the CSV streamer and makes it ready to accept data.
	 *
	 * @return void
	 */
	protected function openWriter() {
		if ( $this->shouldAddBOM ) {
			// Adds UTF-8 BOM for Unicode compatibility
			$this->globalFunctionsHelper->fputs( $this->filePointer, EncodingHelper::BOM_UTF8 );
		}
	}

	/**
	 * Adds data to the currently opened writer.
	 *
	 * @param  array $dataRow Array containing data to be written.
	 *          Example $dataRow = ['data1', 1234, null, '', 'data5'];
	 * @param \Box\Spout\Writer\Style\Style $style Ignored here since CSV does not support styling.
	 * @return void
	 * @throws \Box\Spout\Common\Exception\IOException If unable to write data
	 */
	protected function addRowToWriter( array $dataRow, $style ) {
		$wasWriteSuccessful = $this->globalFunctionsHelper->fputcsv( $this->filePointer, $dataRow, $this->fieldDelimiter, $this->fieldEnclosure );
		if ( $wasWriteSuccessful === false ) {
			throw new IOException( 'Unable to write data' );
		}

		$this->lastWrittenRowIndex++;
		if ( $this->lastWrittenRowIndex % self::FLUSH_THRESHOLD === 0 ) {
			$this->globalFunctionsHelper->fflush( $this->filePointer );
		}
	}

	/**
	 * Closes the CSV streamer, preventing any additional writing.
	 * If set, sets the headers and redirects output to the browser.
	 *
	 * @return void
	 */
	protected function closeWriter() {
		$this->lastWrittenRowIndex = 0;
	}
}