<?php

namespace Box\Spout\Reader\ODS\Helper;

/**
 * Class CellValueFormatter
 * This class provides helper functions to format cell values
 *
 * @package Box\Spout\Reader\ODS\Helper
 */
class CellValueFormatter {

	/** Definition of all possible cell types */
	const CELL_TYPE_STRING     = 'string';
	const CELL_TYPE_FLOAT      = 'float';
	const CELL_TYPE_BOOLEAN    = 'boolean';
	const CELL_TYPE_DATE       = 'date';
	const CELL_TYPE_TIME       = 'time';
	const CELL_TYPE_CURRENCY   = 'currency';
	const CELL_TYPE_PERCENTAGE = 'percentage';
	const CELL_TYPE_VOID       = 'void';

	/** Definition of XML nodes names used to parse data */
	const XML_NODE_P    = 'p';
	const XML_NODE_S    = 'text:s';
	const XML_NODE_A    = 'text:a';
	const XML_NODE_SPAN = 'text:span';

	/** Definition of XML attributes used to parse data */
	const XML_ATTRIBUTE_TYPE          = 'office:value-type';
	const XML_ATTRIBUTE_VALUE         = 'office:value';
	const XML_ATTRIBUTE_BOOLEAN_VALUE = 'office:boolean-value';
	const XML_ATTRIBUTE_DATE_VALUE    = 'office:date-value';
	const XML_ATTRIBUTE_TIME_VALUE    = 'office:time-value';
	const XML_ATTRIBUTE_CURRENCY      = 'office:currency';
	const XML_ATTRIBUTE_C             = 'text:c';

	/** @var bool Whether date/time values should be returned as PHP objects or be formatted as strings */
	protected $shouldFormatDates;

	/** @var \Box\Spout\Common\Escaper\ODS Used to unescape XML data */
	protected $escaper;

	/**
	 * @param bool $shouldFormatDates Whether date/time values should be returned as PHP objects or be formatted as strings
	 */
	public function __construct( $shouldFormatDates ) {
		 $this->shouldFormatDates = $shouldFormatDates;

		/** @noinspection PhpUnnecessaryFullyQualifiedNameInspection */
		$this->escaper = \Box\Spout\Common\Escaper\ODS::getInstance();
	}

	/**
	 * Returns the (unescaped) correctly marshalled, cell value associated to the given XML node.
	 * @see http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#refTable13
	 *
	 * @param \DOMNode $node
	 * @return string|int|float|bool|\DateTime|\DateInterval|null The value associated with the cell, empty string if cell's type is void/undefined, null on error
	 */
	public function extractAndFormatNodeValue( $node ) {
		$cellType = $node->getAttribute( self::XML_ATTRIBUTE_TYPE );

		switch ( $cellType ) {
			case self::CELL_TYPE_STRING:
				return $this->formatStringCellValue( $node );
			case self::CELL_TYPE_FLOAT:
				return $this->formatFloatCellValue( $node );
			case self::CELL_TYPE_BOOLEAN:
				return $this->formatBooleanCellValue( $node );
			case self::CELL_TYPE_DATE:
				return $this->formatDateCellValue( $node );
			case self::CELL_TYPE_TIME:
				return $this->formatTimeCellValue( $node );
			case self::CELL_TYPE_CURRENCY:
				return $this->formatCurrencyCellValue( $node );
			case self::CELL_TYPE_PERCENTAGE:
				return $this->formatPercentageCellValue( $node );
			case self::CELL_TYPE_VOID:
			default:
				return '';
		}
	}

	/**
	 * Returns the cell String value.
	 *
	 * @param \DOMNode $node
	 * @return string The value associated with the cell
	 */
	protected function formatStringCellValue( $node ) {
		 $pNodeValues = array();
		$pNodes       = $node->getElementsByTagName( self::XML_NODE_P );

		foreach ( $pNodes as $pNode ) {
			$currentPValue = '';

			foreach ( $pNode->childNodes as $childNode ) {
				if ( $childNode instanceof \DOMText ) {
					$currentPValue .= $childNode->nodeValue;
				} elseif ( $childNode->nodeName === self::XML_NODE_S ) {
					$spaceAttribute = $childNode->getAttribute( self::XML_ATTRIBUTE_C );
					$numSpaces      = ( ! empty( $spaceAttribute ) ) ? intval( $spaceAttribute ) : 1;
					$currentPValue .= str_repeat( ' ', $numSpaces );
				} elseif ( $childNode->nodeName === self::XML_NODE_A || $childNode->nodeName === self::XML_NODE_SPAN ) {
					$currentPValue .= $childNode->nodeValue;
				}
			}

			$pNodeValues[] = $currentPValue;
		}

		$escapedCellValue = implode( "\n", $pNodeValues );
		$cellValue        = $this->escaper->unescape( $escapedCellValue );
		return $cellValue;
	}

	/**
	 * Returns the cell Numeric value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return int|float The value associated with the cell
	 */
	protected function formatFloatCellValue( $node ) {
		$nodeValue    = $node->getAttribute( self::XML_ATTRIBUTE_VALUE );
		$nodeIntValue = intval( $nodeValue );
		// The "==" is intentionally not a "===" because only the value matters, not the type
		$cellValue = ( $nodeIntValue == $nodeValue ) ? $nodeIntValue : floatval( $nodeValue );
		return $cellValue;
	}

	/**
	 * Returns the cell Boolean value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return bool The value associated with the cell
	 */
	protected function formatBooleanCellValue( $node ) {
		$nodeValue = $node->getAttribute( self::XML_ATTRIBUTE_BOOLEAN_VALUE );
		// !! is similar to boolval()
		$cellValue = ! ! $nodeValue;
		return $cellValue;
	}

	/**
	 * Returns the cell Date value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return \DateTime|string|null The value associated with the cell or NULL if invalid date value
	 */
	protected function formatDateCellValue( $node ) {
		// The XML node looks like this:
		// <table:table-cell calcext:value-type="date" office:date-value="2016-05-19T16:39:00" office:value-type="date">
		//   <text:p>05/19/16 04:39 PM</text:p>
		// </table:table-cell>

		if ( $this->shouldFormatDates ) {
			// The date is already formatted in the "p" tag
			$nodeWithValueAlreadyFormatted = $node->getElementsByTagName( self::XML_NODE_P )->item( 0 );
			return $nodeWithValueAlreadyFormatted->nodeValue;
		} else {
			// otherwise, get it from the "date-value" attribute
			try {
				$nodeValue = $node->getAttribute( self::XML_ATTRIBUTE_DATE_VALUE );
				return new \DateTime( $nodeValue );
			} catch ( \Exception $e ) {
				return null;
			}
		}
	}

	/**
	 * Returns the cell Time value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return \DateInterval|string|null The value associated with the cell or NULL if invalid time value
	 */
	protected function formatTimeCellValue( $node ) {
		// The XML node looks like this:
		// <table:table-cell calcext:value-type="time" office:time-value="PT13H24M00S" office:value-type="time">
		//   <text:p>01:24:00 PM</text:p>
		// </table:table-cell>

		if ( $this->shouldFormatDates ) {
			// The date is already formatted in the "p" tag
			$nodeWithValueAlreadyFormatted = $node->getElementsByTagName( self::XML_NODE_P )->item( 0 );
			return $nodeWithValueAlreadyFormatted->nodeValue;
		} else {
			// otherwise, get it from the "time-value" attribute
			try {
				$nodeValue = $node->getAttribute( self::XML_ATTRIBUTE_TIME_VALUE );
				return new \DateInterval( $nodeValue );
			} catch ( \Exception $e ) {
				return null;
			}
		}
	}

	/**
	 * Returns the cell Currency value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return string The value associated with the cell (e.g. "100 USD" or "9.99 EUR")
	 */
	protected function formatCurrencyCellValue( $node ) {
		$value    = $node->getAttribute( self::XML_ATTRIBUTE_VALUE );
		$currency = $node->getAttribute( self::XML_ATTRIBUTE_CURRENCY );

		return "$value $currency";
	}

	/**
	 * Returns the cell Percentage value from the given node.
	 *
	 * @param \DOMNode $node
	 * @return int|float The value associated with the cell
	 */
	protected function formatPercentageCellValue( $node ) {
		 // percentages are formatted like floats
		return $this->formatFloatCellValue( $node );
	}
}