PO::read_entry( resource $f, int $lineno = 0 ): null|false|array

328		public function read_entry( $f, $lineno = 0 ) {329			$entry = new Translation_Entry();330			// Where were we in the last step.331			// Can be: comment, msgctxt, msgid, msgid_plural, msgstr, msgstr_plural.332			$context      = '';333			$msgstr_index = 0;334			while ( true ) {335				++$lineno;336				$line = PO::read_line( $f );337				if ( ! $line ) {338					if ( feof( $f ) ) {339						if ( self::is_final( $context ) ) {340							break;341						} elseif ( ! $context ) { // We haven't read a line and EOF came.342							return null;343						} else {344							return false;345						}346					} else {347						return false;348					}349				}350				if ( "\n" === $line ) {351					continue;352				}353				$line = trim( $line );354				if ( preg_match( '/^#/', $line, $m ) ) {355					// The comment is the start of a new entry.356					if ( self::is_final( $context ) ) {357						PO::read_line( $f, 'put-back' );358						--$lineno;359						break;360					}361					// Comments have to be at the beginning.362					if ( $context && 'comment' !== $context ) {363						return false;364					}365					// Add comment.366					$this->add_comment_to_entry( $entry, $line );367				} elseif ( preg_match( '/^msgctxt\s+(".*")/', $line, $m ) ) {368					if ( self::is_final( $context ) ) {369						PO::read_line( $f, 'put-back' );370						--$lineno;371						break;372					}373					if ( $context && 'comment' !== $context ) {374						return false;375					}376					$context         = 'msgctxt';377					$entry->context .= PO::unpoify( $m[1] );378				} elseif ( preg_match( '/^msgid\s+(".*")/', $line, $m ) ) {379					if ( self::is_final( $context ) ) {380						PO::read_line( $f, 'put-back' );381						--$lineno;382						break;383					}384					if ( $context && 'msgctxt' !== $context && 'comment' !== $context ) {385						return false;386					}387					$context          = 'msgid';388					$entry->singular .= PO::unpoify( $m[1] );389				} elseif ( preg_match( '/^msgid_plural\s+(".*")/', $line, $m ) ) {390					if ( 'msgid' !== $context ) {391						return false;392					}393					$context          = 'msgid_plural';394					$entry->is_plural = true;395					$entry->plural   .= PO::unpoify( $m[1] );396				} elseif ( preg_match( '/^msgstr\s+(".*")/', $line, $m ) ) {397					if ( 'msgid' !== $context ) {398						return false;399					}400					$context             = 'msgstr';401					$entry->translations = array( PO::unpoify( $m[1] ) );402				} elseif ( preg_match( '/^msgstr\[(\d+)\]\s+(".*")/', $line, $m ) ) {403					if ( 'msgid_plural' !== $context && 'msgstr_plural' !== $context ) {404						return false;405					}406					$context                      = 'msgstr_plural';407					$msgstr_index                 = $m[1];