#!"C:\xampp\perl\bin\perl.exe"

use strict;
use LWP::Simple;
use CGI qw(:standard :cgi-lib);
use CGI::Carp qw(fatalsToBrowser warningsToBrowser);

my $current;
my $currentUrl;
my $title;
my $alt;
my $cgi = new CGI;

print $cgi->header();

print start_html(-title =>'Save XKCD');

# Set Specifics
my $sitePrefix = "https://xkcd.com/";
#my $sitePrefix = "http://www.google.com/";

## Path to main XKCD directory ##
my $path = "c:/Comics";

mkdir "$path/xkcd", 0755 or print "$path/xkcd Directory Exists\n",br;
chomp($path = "$path/xkcd");

my $d = get("$sitePrefix");

if (!is_success($d)) {
	print "$d is not defined",br;
} else {
	print "[ $d ]",br;
}
my $status;
my $content;
print "status = $status",br,"Content = $content",br;
if ($d =~ /https:\/\/xkcd.com\/(\d+)\//) {
    $current = $1;
	print "Current = $current",br,"SitePrefix = $sitePrefix",br;
} else {
	print "Permanent link not found",br;
	print "sitePrefix - ",$sitePrefix,br;
	print "\$d - [",$d,"]",br;
}

# Obtains all individual comic data
sub getComicData {
    my $siteData = get("$sitePrefix$current/");
    my @data = split /\n/, $siteData;
    foreach (@data) {
        if (/http:\/\/xkcd.com\/(\d+)\//) {
            $current = $1;
        }
        if ((/src="(http:\/\/imgs.xkcd.com\/comics\/.+\.\w{3})"/) ||
		    (/src="(\/\/imgs.xkcd.com\/comics\/.+\.\w{3})"/) ) {
            $currentUrl = $1;
			  print "CurrentUrl = $currentUrl",br;
            if (/alt="(.+?)"/) {
                $title = $1;
                $title = "House of Pancakes" if $current == 472;  # Color title on comic 472 with weird syntax
				  print "Title = $title",br;
				}
            if (/title="(.+?)"/) {    #title commonly know as 'alt' text
                $alt = $1;
				  print "Alt = $alt",br;
            }
        }
    }
}

chdir "$path" or die "Cannot change directory: $!";
&getComicData();
while ( get("$sitePrefix$current/")){ 
    
    print "Writing Files $current: $title\n",br,"CurrentUrl = $currentUrl",br,br;
    # Create directories for individual comics
    mkdir "$current $title", 0755 or die "Previously Downloaded";
    chdir "$path/$current $title" or die "Cannot change directory: $!";
    # Save image file
	if (index($currentUrl,"http") != 0) {
		$currentUrl = "http:".$currentUrl;
	}
    my $image = get($currentUrl);
    open my $IMAGE, '>>', "$title.png"
      or die "Cannot create image file!";
	binmode($IMAGE);
    print $IMAGE $image;
    close $IMAGE;

    # Save alt text
    open my $TXT, '>>', "$title ALT.txt"
      or die "Cannot create text file!";
    print $TXT $alt;
    close $TXT;
    chdir "$path" or die "Cannot change directory: $!";
    $current--;

    # Check for non existent 404 comic
    $current-- if $current == 404;

    &getComicData();
}


# End Gracefully
print "Download Complete\n";
print end_html;