d', $baseTimestamp );

		$this->setDateRange( $startDate, $endDate );
	}

	/**
	 * Updates the date range.
	 *
	 * @since 4.3.0
	 *
	 * @param  string $startDate The start date.
	 * @param  string $endDate   The end date.
	 * @return void
	 */
	public function setDateRange( $startDate, $endDate ) {
		$this->startDate = $startDate;
		$this->endDate   = $endDate;

		// Timestamp.
		$this->startTimestamp = strtotime( $startDate );
		$this->endTimestamp   = strtotime( $endDate );

		// Compare date.
		$this->days       = ceil( abs( $this->endTimestamp - $this->startTimestamp ) / DAY_IN_SECONDS ) + 1;
		$compareEndDate   = $this->startTimestamp - DAY_IN_SECONDS;
		$compareStartDate = $compareEndDate - ( $this->days * DAY_IN_SECONDS );

		$this->compareStartDate = date( 'Y-m-d', $compareStartDate );
		$this->compareEndDate   = date( 'Y-m-d', $compareEndDate );
	}

	/**
	 * Returns the current date range.
	 *
	 * @since 4.3.0
	 *
	 * @return array The current date range.
	 */
	public function getDateRange() {
		return [
			'start'        => $this->startDate,
			'end'          => $this->endDate,
			'compareStart' => $this->compareStartDate,
			'compareEnd'   => $this->compareEndDate
		];
	}
}