use diagnostics;
use strict;
use warnings;

#sets password ranges
my @password;
my $password;
my $password_length = 0;
my $user_length = 0;
#seperate arrays for each password type
my @chars1 = ('0'..'9');
my @chars2 = ('A'..'Z');
my @chars3 = ('a'..'z');
my @chars4 = ('A'..'Z', 'a'..'z');
my @chars5 = ('A'..'Z', 'a'..'z', '0'..'9');
my @chars6 = ('0'..'9', 'a'..'z', 'A'..'Z', '!','@', '#', '$', '%',
'^', '&', '*', '(', ')', '<', '>', '?', '`', '+', '/', '[', '{', ']',
'}', '|', '=', '_','~', ',', '.');

#user inputs required length of password
print "Enter the required password length. ";
chomp($user_length = <STDIN>);
print "\n";

#user selects level of complexity12
print "Select a level of complexity for your password: \n";
print "1. Numeric passcode\t\t\t\t(low level of security) \n";
print "2. Single case alphabetic\t\t\t(low level of security) \n";
print "3. Multi-case alphabetic\t\t\t(low level of security) \n";
print "4. Alphanumeric\t\t\t\t\t(medium level of security) \n";
print "5. Alphanumeric with special characters\t\t(high level of security) \n";
print "Complexity level: ";
chomp(my $level = <STDIN>);
print "\n";

if ($level > 1) {
	while ($user_length < 14) {
		print "*********************************\n";
		print "*\t\tError!\t\t*\n";
		print "*********************************\n";
		print "\n";
		print "Strong password guidelines require a minimum password length of 14 characters.";
		print "\n";
		print "\n";
		print "Do you want to generate a password which conforms to strong password guidelines? \n";
		chomp (my $guidelines = <STDIN>);
		if ($guidelines =~ m/^y/i) {
			print "Enter a new password length: ";
			chomp ($user_length = <STDIN>);
		} elsif ($guidelines =~ m/^n/i) {
			goto PW;
		}
	}
}

PW:
if ($level == 1) {
 	#mixed case password
 	print "Generating a numeric passcode.";
 	#increments until $user_length is met
 	while ($password_length <= ($user_length-1)) {
  		$password = $chars1[int rand @chars1];
  		push @password, $password;
		++$password_length;
	}
} elsif ( $level == 2) {
	#single case password
	print "Select case: \n";
	print "1. Upper \n";
	print "2. Lower \n";
	print "Case: ";
	chomp(my $case = <STDIN>);	
		if ($case == 1) {
			#uppercase password
  			print "Generating an uppercase password.";
  			#increments until $user_length is met
  			while ($password_length <= ($user_length-1)) {
   				$password = $chars2[int rand @chars2];
   				push @password, $password;
   				++$password_length;
  			}
 		} else {
  			#lower case password
  			print "Generating a lower case password.";
  			#increments until $user_length is met
  			while ($password_length <= ($user_length-1)) {
   				$password = $chars3[int rand @chars3];
   				push @password, $password;
   				++$password_length;
  			}
 		}
} elsif ($level == 3) {
 	#mixed case password
 	print "Generating a mixed case password.";
 	#increments until $user_length is met
 	while ($password_length <= ($user_length-1)) {
  		$password = $chars4[int rand @chars4];
  		push @password, $password;
		++$password_length;
	}
} elsif ($level == 4) {
	#alphanumeric password
 	print "Generating an alphanumeric password.";
	#increments until $user_length is met
	while ($password_length <= ($user_length-1)) {
		$password = $chars5[int rand @chars5];
		push @password, $password;
		++$password_length;
	}
} else {
	#alphanumeric password with special characters
	print "Generating an alphanumeric password with special characters.";
	#increments until $user_length is met
	while ($password_length <= ($user_length-1)) {
 		$password = $chars6[int rand @chars6];
 		push @password, $password;
		++$password_length;
	}
}

#start export function
print "Do you want to export your password to a text file? (y/n) ";
chomp(my $export = <STDIN>);
print "\n";

if ($export =~ m/^y/i) {
	open (FH, '>>password.txt') or die $!;
	print FH "Your password is: ", @password, "\n";
	close FH;
} elsif ($export =~ m/^n/i) {
	print "Your password is: ", @password ,"\n";
} else {
	print "Enter either y or n to continue. \n" ;
	#needs to return to top of $export function
}

print "\n";
print "\n";
print "Your password has been generated. \n";