bbp_get_time_since( string $older_date, string $newer_date = false, int $gmt = false )

	function bbp_get_time_since( $older_date, $newer_date = false, $gmt = false ) {

		// Setup the strings
		$unknown_text   = apply_filters( 'bbp_core_time_since_unknown_text',   __( 'sometime',  'buddyboss' ) );
		$right_now_text = apply_filters( 'bbp_core_time_since_right_now_text', __( 'right now', 'buddyboss' ) );
		$ago_text       = apply_filters( 'bbp_core_time_since_ago_text',       __( '%s ago',    'buddyboss' ) );

		// array of time period chunks
		$chunks = array(
			array( 60 * 60 * 24 * 365 , __( 'year',   'buddyboss' ), __( 'years',   'buddyboss' ) ),
			array( 60 * 60 * 24 * 30 ,  __( 'month',  'buddyboss' ), __( 'months',  'buddyboss' ) ),
			array( 60 * 60 * 24 * 7,    __( 'week',   'buddyboss' ), __( 'weeks',   'buddyboss' ) ),
			array( 60 * 60 * 24 ,       __( 'day',    'buddyboss' ), __( 'days',    'buddyboss' ) ),
			array( 60 * 60 ,            __( 'hour',   'buddyboss' ), __( 'hours',   'buddyboss' ) ),
			array( 60 ,                 __( 'minute', 'buddyboss' ), __( 'minutes', 'buddyboss' ) ),
			array( 1,                   __( 'second', 'buddyboss' ), __( 'seconds', 'buddyboss' ) )
		);

		if ( !empty( $older_date ) && !is_numeric( $older_date ) ) {
			$time_chunks = explode( ':', str_replace( ' ', ':', $older_date ) );
			$date_chunks = explode( '-', str_replace( ' ', '-', $older_date ) );
			$older_date  = gmmktime( (int) $time_chunks[1], (int) $time_chunks[2], (int) $time_chunks[3], (int) $date_chunks[1], (int) $date_chunks[2], (int) $date_chunks[0] );
		}

		// $newer_date will equal false if we want to know the time elapsed
		// between a date and the current time. $newer_date will have a value if
		// we want to work out time elapsed between two known dates.
		$newer_date = ( !$newer_date ) ? strtotime( current_time( 'mysql', $gmt ) ) : $newer_date;

		// Difference in seconds
		$since = $newer_date - $older_date;

		// Something went wrong with date calculation and we ended up with a negative date.
		if ( 0 > $since ) {
			$output = $unknown_text;

		// We only want to output two chunks of time here, eg:
		//     x years, xx months
		//     x days, xx hours
		// so there's only two bits of calculation below:
		} else {

			// Step one: the first chunk
			for ( $i = 0, $j = count( $chunks ); $i < $j; ++$i ) {
				$seconds = $chunks[$i][0];

				// Finding the biggest chunk (if the chunk fits, break)
				$count = floor( $since / $seconds );
				if ( 0 != $count ) {
					break;
				}
			}

			// If $i iterates all the way to $j, then the event happened 0 seconds ago
			if ( !isset( $chunks[$i] ) ) {
				$output = $right_now_text;

			} else {

				// Set output var
				$output = ( 1 == $count ) ? '1 '. $chunks[$i][1] : $count . ' ' . $chunks[$i][2];

				// Step two: the second chunk
				if ( $i + 2 < $j ) {
					$seconds2 = $chunks[$i + 1][0];
					$name2    = $chunks[$i + 1][1];
					$count2   = floor( ( $since - ( $seconds * $count ) ) / $seconds2 );

					// Add to output var
					if ( 0 != $count2 ) {
						$output .= ( 1 == $count2 ) ? _x( ',', 'Separator in time since', 'buddyboss' ) . ' 1 '. $name2 : _x( ',', 'Separator in time since', 'buddyboss' ) . ' ' . $count2 . ' ' . $chunks[$i + 1][2];
					}
				}

				// No output, so happened right now
				if ( ! (int) trim( $output ) ) {
					$output = $right_now_text;
				}
			}
		}

		// Append 'ago' to the end of time-since if not 'right now'
		if ( $output != $right_now_text ) {
			$output = sprintf( $ago_text, $output );
		}

		return apply_filters( 'bbp_get_time_since', $output, $older_date, $newer_date );
	}