[WIP] Add DateFormatParser

src/ValueParsers/DateFormatParser.php

@@ -0,0 +1,264 @@
+<?php
+
+namespace ValueParsers;
+
+use DataValues\TimeValue;
+
+/**
+ * This parser is in essence the inverse operation of Language::sprintfDate.
+ *
+ * @see Language::sprintfDate
+ *
+ * @since 0.8.1
+ *
+ * @licence GNU GPL v2+
+ * @author Thiemo Mättig
+ */
+class DateFormatParser extends StringValueParser {
+
+	const FORMAT_NAME = 'datetime';
+
+	const OPT_DATE_FORMAT = 'dateFormat';
+
+	/**
+	 * Option for unlocalizing non-canonical digits. Must be an array of strings, mapping canonical
+	 * digit characters ("1", "2" and so on, possibly including "." and ",") to localized
+	 * characters.
+	 */
+	const OPT_DIGIT_TRANSFORM_TABLE = 'digitTransformTable';
+
+	/**
+	 * Option for localized month names. Should be a two-dimensional array, the first dimension
+	 * mapping the month's numbers 1 to 12 to arrays of localized month names, possibly including
+	 * full month names, genitive names and abbreviations. Can also be a one-dimensional array of
+	 * strings.
+	 */
+	const OPT_MONTH_NAMES = 'monthNames';
+
+	public function __construct( ParserOptions $options = null ) {
+		parent::__construct( $options );
+
+		$this->defaultOption( self::OPT_DATE_FORMAT, 'j F Y' );
+		// FIXME: Should not be an option. Options should be trivial, never arrays or objects!
+		$this->defaultOption( self::OPT_DIGIT_TRANSFORM_TABLE, null );
+		$this->defaultOption( self::OPT_MONTH_NAMES, null );
+	}
+
+	/**
+	 * @see StringValueParser::stringParse
+	 *
+	 * @param string $value
+	 *
+	 * @throws ParseException
+	 * @return TimeValue
+	 */
+	protected function stringParse( $value ) {
+		$pattern = $this->parseDateFormat( $this->getDateFormat() );
+
+		if ( @preg_match( '<^\p{Z}*' . $pattern . '$>iu', $value, $matches )
+			&& isset( $matches['year'] )
+		) {
+			$precision = TimeValue::PRECISION_YEAR;
+			$time = array( $this->parseFormattedNumber( $matches['year'] ), 0, 0, 0, 0, 0 );
+
+			if ( isset( $matches['month'] ) ) {
+				$precision = TimeValue::PRECISION_MONTH;
+				$time[1] = $this->findMonthMatch( $matches );
+			}
+
+			if ( isset( $matches['day'] ) ) {
+				$precision = TimeValue::PRECISION_DAY;
+				$time[2] = $this->parseFormattedNumber( $matches['day'] );
+			}
+
+			if ( isset( $matches['hour'] ) ) {
+				$precision = TimeValue::PRECISION_HOUR;
+				$time[3] = $this->parseFormattedNumber( $matches['hour'] );
+			}
+
+			if ( isset( $matches['minute'] ) ) {
+				$precision = TimeValue::PRECISION_MINUTE;
+				$time[4] = $this->parseFormattedNumber( $matches['minute'] );
+			}
+
+			if ( isset( $matches['second'] ) ) {
+				$precision = TimeValue::PRECISION_SECOND;
+				$time[5] = $this->parseFormattedNumber( $matches['second'] );
+			}
+
+			$timestamp = vsprintf( '+%04s-%02s-%02sT%02s:%02s:%02sZ', $time );
+			return new TimeValue( $timestamp, 0, 0, 0, $precision, TimeValue::CALENDAR_GREGORIAN );
+		}
+
+		throw new ParseException( "Failed to parse $value ("
+			. $this->parseFormattedNumber( $value ) . ')', $value );
+	}
+
+	/**
+	 * @see Language::sprintfDate
+	 *
+	 * @param string $format A date format, as described in Language::sprintfDate.
+	 *
+	 * @return string Regular expression
+	 */
+	private function parseDateFormat( $format ) {
+		$length = strlen( $format );
+		$numberPattern = '[' . $this->getNumberCharacters() . ']';
+		$pattern = '';
+
+		for ( $p = 0; $p < $length; $p++ ) {
+			$code = $format[$p];
+
+			if ( $code === 'x' && $p < $length - 1 ) {
+				$code .= $format[++$p];
+			}
+
+			if ( preg_match( '<^x[ijkmot]$>', $code ) && $p < $length - 1 ) {
+				$code .= $format[++$p];
+			}
+
+			switch ( $code ) {
+				case 'Y':
+					$pattern .= '(?P<year>' . $numberPattern . '+)\p{Z}*';
+					break;
+				case 'F':
+				case 'm':
+				case 'M':
+				case 'n':
+				case 'xg':
+					$pattern .= '(?P<month>' . $numberPattern . '{1,2}'
+						. $this->getMonthNamesPattern()
+						. ')\p{P}*\p{Z}*';
+					break;
+				case 'd':
+				case 'j':
+					$pattern .= '(?P<day>' . $numberPattern . '{1,2})\p{P}*\p{Z}*';
+					break;
+				case 'G':
+				case 'H':
+					$pattern .= '(?P<hour>' . $numberPattern . '{1,2})\p{Z}*';
+					break;
+				case 'i':
+					$pattern .= '(?P<minute>' . $numberPattern . '{1,2})\p{Z}*';
+					break;
+				case 's':
+					$pattern .= '(?P<second>' . $numberPattern . '{1,2})\p{Z}*';
+					break;
+				case '\\':
+					if ( $p < $length - 1 ) {
+						$pattern .= preg_quote( $format[++$p] );
+					} else {
+						$pattern .= '\\';
+					}
+					break;
+				case '"':
+					$endQuote = strpos( $format, '"', $p + 1 );
+					if ( $endQuote !== false ) {
+						$pattern .= preg_quote( substr( $format, $p + 1, $endQuote - $p - 1 ) );
+						$p = $endQuote;
+					} else {
+						$pattern .= '"';
+					}
+					break;
+				case 'xn':
+				case 'xN':
+					// We can ignore raw and raw toggle when parsing, because we always accept
+					// canonical digits.
+					break;
+				default:
+					if ( preg_match( '<^\p{P}+$>u', $format[$p] ) ) {
+						$pattern .= '\p{P}*';
+					} elseif ( preg_match( '<^\p{Z}+$>u', $format[$p] ) ) {
+						$pattern .= '\p{Z}*';
+					} else {
+						$pattern .= preg_quote( $format[$p] );
+					}
+			}
+		}
+
+		return $pattern;
+	}
+
+	/**
+	 * @return string
+	 */
+	private function getMonthNamesPattern() {
+		$pattern = '';
+
+		foreach ( $this->getMonthNames() as $i => $monthNames ) {
+			$pattern .= '|(?P<month' . $i . '>'
+				. implode( '|', array_map( 'preg_quote', (array)$monthNames ) )
+				. ')';
+		}
+
+		return $pattern;
+	}
+
+	/**
+	 * @param string[] $matches
+	 *
+	 * @return int
+	 */
+	private function findMonthMatch( $matches ) {
+		for ( $i = 1; $i <= 12; $i++ ) {
+			if ( !empty( $matches['month' . $i] ) ) {
+				return $i;
+			}
+		}
+
+		return $this->parseFormattedNumber( $matches['month'] );
+	}
+
+	/**
+	 * @param string $number
+	 *
+	 * @return string
+	 */
+	private function parseFormattedNumber( $number ) {
+		$transformTable = $this->getDigitTransformTable();
+
+		if ( is_array( $transformTable ) ) {
+			// Eliminate empty array values (bug T66347).
+			$transformTable = array_filter( $transformTable );
+			$number = strtr( $number, array_flip( $transformTable ) );
+		}
+
+		return $number;
+	}
+
+	/**
+	 * @return string
+	 */
+	private function getNumberCharacters() {
+		$numberCharacters = '\d';
+
+		$transformTable = $this->getDigitTransformTable();
+		if ( is_array( $transformTable ) ) {
+			$numberCharacters .= preg_quote( implode( '', $transformTable ) );
+		}
+
+		return $numberCharacters;
+	}
+
+	/**
+	 * @return string
+	 */
+	private function getDateFormat() {
+		return $this->getOption( self::OPT_DATE_FORMAT );
+	}
+
+	/**
+	 * @return string[]|null
+	 */
+	private function getDigitTransformTable() {
+		return $this->getOption( self::OPT_DIGIT_TRANSFORM_TABLE );
+	}
+
+	/**
+	 * @return array[]
+	 */
+	private function getMonthNames() {
+		return $this->getOption( self::OPT_MONTH_NAMES ) ?: array();
+	}
+
+}