# First, the current date is determined
use Date::Simple::D8 (':all');
my $today = Date::Simple::D8->today();
my $end_date = $today;

# Prompt user for start date and verify it
print "Please enter the collection start date (YYYYMMDD): ";
my $start_date = <>;
chomp ($start_date);
while ($start_date !~ (/\d\d\d\d\d\d\d\d/)) {
	print "ERROR: Invalid format! Start date (YYYYMMDD): ";
	$start_date = <>;
	chomp ($start_date);
	}
while ($start_date < 18960101) {
	print "ERROR: Data prior to 18960101 is not available! Start date (YYYYMMDD): ";
	$start_date = <>;
	chomp ($start_date);
	}
while ($start_date > "$today") {
	print "ERROR: Start date is in the future! Start date (YYYYMMDD): ";
	$start_date = <>;
	chomp ($start_date);
	}
print "Thank you, collection will begin with $start_date\n";

# Ask user if most recent available date should be used as end date
print "Would you like to collect through the most recent available date? (y/n): ";
my $ans = <>;
chomp ($ans);
if ($ans eq "n" || $ans eq "N") {
	print "Please enter the collection end date (YYYYMMDD): ";
	my $end_date = <>;
	chomp ($end_date);
	while ($end_date !~ (/\d\d\d\d\d\d\d\d/)) {
		print "ERROR: Invalid format! End date (YYYYMMDD): ";
		$end_date = <>;
		chomp ($end_date);
	}
	while ($end_date < 18960101) {
		print "ERROR: Data prior to 18960101 is not available! End date (YYYYMMDD): ";
		$end_date = <>;
		chomp ($end_date);
	}
	while ($end_date > "$today") {
		print "ERROR: End date is in the future! End date (YYYYMMDD): ";
		$end_date = <>;
		chomp ($end_date);
	}
	print "Thank you, collection will end with $end_date\n";
}