use strict;
use warnings;
use File::Find;
use Getopt::Long;
use Pod::Usage;
use Carp;

# Parse command line arguments and assign corresponding variables
GetOptions
(
    'r|rootdir=s'   => \( my $rootdir = "./" ),
    'p|pattern=s'   => \( my $pattern = undef ),
    'i'             => \( my $case_sensitive = 0 ),
    'v|verbose'     => \( my $verbose = 0 ),
);

unless ( defined $pattern )
{
    print <<USAGE
Usage: $0 [options]
Options:
 -r|--rootdir [dir]      Specify the top directory
 -p|--pattern [pattern]  Specify the pattern to look for (regex)
 -i                      Case sensitive search
 -v|--verbose            Print more info
USAGE
;
    exit(0);
}

$pattern = "(?i)" . $pattern if $case_sensitive;
print "looking under $rootdir for { /$pattern/ }\n" if $verbose;

find({ wanted => \&filefilter }, $rootdir);

sub filefilter
{
    return if /^\.+$/;
    open FILE, "<$File::Find::name"
         or carp "could not open file: $File::Find::name";
    my $file = do { local $/; <FILE> };
    close FILE;

    print ">> ", $File::Find::name, "\n"
        if $file =~ /$pattern/;
}