#!/usr/bin/perl -w

# "!read username" will read username's e-mail address.
# "!write username user@example.com" will set username's e-mail address
# to user@example.com.
#
# Commands must be handled case-insensitively.

use strict;

print ("Hello there, what would you like to do? ");
my $input_command = <STDIN>;
chomp ($input_command);

# Break $input_command into a space-delimited array and assign only the
# first element (which will be the command) to $command.
my $command = (split /\s/, $input_command)[0];
$command =~ tr/A-Z/a-z/; # lowercase everything

# Take the second element (the name) and assign it to $name
my $name = (split /\s/, $input_command)[1];

# Take the third element and assign it to $address
my $address = (split /\s/, $input_command)[2];

if ($command =~ /!read\b/ || $command =~ /!write\b/) {
    print ("The command you entered is $command\n");
    if ($name) { print ("The name you entered is $name\n"); }
    if ($address) { print ("The address you entered is $address\n"); }
    dbhandler($command, $name, $address);
}
else {
    print ("Sorry, only !read and !write are valid commands.\n");
}

sub dbhandler {
    my ($subcommand, $subname, $subaddress) = @_;
    
    # lowercase everything. $subcommand is already received lowercase
    $subname =~ tr/A-Z/a-z/;
    $subaddress =~ tr/A-Z/a-z/;

    if ($subcommand =~ /!read\b/ {
            open ADDYFILE, "addyfile" || die "Couldn't open file: $!";
    # rest of the subroutine should go here