#!/usr/bin/perl -w

use strict;

use Chemistry::Elements qw/get_name get_Z get_symbol/;

my $test_type = shift || "";

my %tests = (
    name   => \&name_test,
    number => \&number_test,
    symbol => \&symbol_test,  );

if (exists $tests{$test_type}) {
    $tests{$test_type}->();
} else {
    error("Invalid Test type. Choose 'name', 'number', or 'symbol'.");
}

sub name_test {

    while (1) {

        my $number = int(rand 109) + 1;
        my $symbol = get_symbol($number);
        my $name   = get_name($number);

        print "Element name = $name\n";
        print "Enter symbol: ";

        chomp (my $ans_symbol = <STDIN>);

        if (lc($ans_symbol) eq lc($symbol)) {
            print "Correct. $symbol is the atomic symbol for $name\n";
        } else {
            print "Incorrect. $symbol is the atomic symbol for $name\n
+";
        }

        print "Enter $name\'s atomic number: ";

        chomp (my $ans_number = <STDIN>);

        if ($ans_number eq $number) {
            print "Correct. The atomic number for $name is $number\n";
        } else {
            print "Incorrect. The atomic number for $name is $number\n
+";
        }

        print "\n";
    }

}

sub number_test {

    while (1) {

        my $number = int(rand 109) + 1;
        my $symbol = get_symbol($number);
        my $name   = get_name($number);

        print "Atomic number = $number\n";
        print "Enter symbol: ";

        chomp (my $ans_symbol = <STDIN>);

        if (lc($ans_symbol) eq lc($symbol)) {
            print "Correct. $symbol has the atomic number $number\n";
        } else {
            print "Incorrect. $symbol has the atomic number $number\n"
+;
        }

        print "Which element has the atomic number $number: ";

        chomp (my $ans_name = <STDIN>);

        if (lc($ans_name) eq lc($name)) {
            print "Correct. $number is the atomic number for $name\n";
        } else {
            print "Incorrect. $number is the atomic number for $name\n
+";
        }

        print "\n";
    }

}

sub symbol_test {

    while (1) {

        my $number = int(rand 109) + 1;
        my $symbol = get_symbol($number);
        my $name   = get_name($number);

        print "Element symbol = $symbol\n";
        print "Enter Name: ";

        chomp (my $ans_name = <STDIN>);

        if (lc($ans_name) eq lc($name)) {
            print "Correct. $symbol is the symbol for $name\n";
        } else {
            print "Incorrect. $symbol is the symbol for $name\n";
        }

        print "Enter $symbol\'s atomic number: ";

        chomp (my $ans_number = <STDIN>);

        if ($ans_number eq $number) {
            print "Correct. $symbol\'s atomic number is $number\n";
        } else {
            print "Incorrect. $symbol\'s atomic number is $number\n";
        }

        print "\n";
    }

}


sub error {
    my $error = shift;
    print "Error: $error\n";
    exit;
}