#!/usr/bin/perl
##########################################################################
# get a URL content (html or otherwise) from a host server
# optionally snip a piece of the returned content
#     Receives the url requested
#              the case sensitive string to search for (optional) 
#              the offset from the beginning of the string (optional)
#              the length of the snipet (optional)
#     Returns the data requested, or an error message
##########################################################################

$requestURL = $ARGV[0];
$searchFor  = $ARGV[1];
$offset     = $ARGV[2];
$length     = $ARGV[3];

if ($requestURL eq '') {
    print ("Usage: $0 requestedURL [searchString offset length] \n");
    exit(-1);
}

if ($searchFor && ($offset == '' || $length == '')) {
    print ("Usage: $0 requestedURL [searchString offset length] \n");
    exit(-2);
}

$data = &getURL($requestURL);

if ($searchFor) {
    $data = &snip(\$data, $searchFor, $offset, $length);
}

print ($data, "\n");

############################################################################
# Get an HTML page or other URL from the web
#     Receives the url requested
#     Returns the data received or an error message
############################################################################
sub getURL {

    my $url = $_[0];                    # get requested URL from $_ 
       $url = "http://" . $url;         # prepend "http://"

    use LWP::UserAgent;                 # use LWP UserAgent method                                            
    $browser = new LWP::UserAgent;      # create a new user agent                                               
#   $browser->agent("Name: " . $browser->agent);                                    
    # Create a request 
    my $req = new HTTP::Request(GET => $url);

#   $req->content_type('application/x-www-form-urlencoded');
#   $req->content('match=www&errors=0');
                                                                                
    # Send request and get a response back 
    my $resp = $browser->request($req);                                                 
    ($resp->is_success) 
        ? return($resp->content)
        : return('Bad request, or URL not found');
}

########################################################################
# Snip a piece of data from large data
#     Receives a 'reference' to a large data string
#              a string to search for
#              an offset from the beginning of the search string
#              the length of the returned snipped
#     Returns the data snippet
########################################################################
sub snip {

    my $dataref = $_[0];           # get the reference to large data
    my $find    = $_[1];           # get the search string 
    my $from    = $_[2];           # get the offset + or - 
    my $lgth    = $_[3];           # get the length of the snipet

    $foundAt = index($$dataref, $find);   # search for $find in $data

    if ($foundAt == -1) {
        return("String not found");
    }

    my $snipet = substr($$dataref, $foundAt+$from, $lgth);   # snip it

    return $snipet;
}