#!/usr/bin/perl
# PINSS.plx
# Short for "Pins Is Not a Sentient Searcher"

use strict;
use warnings;

sub pry;
my $file_in;
my $file_out;

print "Please input the phrase or perl regular expression you want to use to begin capturing data: ";
chomp(my $start_exp = <STDIN>);
print "Please input the phase or perl regular expression you want to use to cessate capture of data: ";
chomp(my $stop_exp = <STDIN>);

if(scalar  @ARGV > 1){
	$file_in = shift @ARGV;
	$file_out = shift @ARGV;
	print "\nINPUT FILE: $file_in\n";
	print "OUTPUT FILE: $file_out\n";

	pry($file_in, $file_out, $start_exp, $stop_exp);

	print "\n\nSee $file_out for results\n\n";
}elsif(scalar @ARGV == 1){
	$file_in = shift;
	print "Please specify an output file to print to (type 'screen' to print to terminal screen): ";
	chomp($file_out = <STDIN>);
	print "\nINPUT FILE: $file_in\n";
	print "OUTPUT FILE: $file_out\n";

	pry($file_in, $file_out, $start_exp, $stop_exp);

	print "\n\nSee $file_out for results\n\n";
}else{
	print "Please specify an input file to read from: ";
	chomp($file_in = <STDIN>);
	print "Please specify an output file to print to (type 'screen' to print to terminal screen): ";
	chomp($file_out = <STDIN>);

	print "\nINPUT FILE: $file_in\n";
	print "OUTPUT FILE: $file_out\n";

	pry($file_in, $file_out, $start_exp, $stop_exp);

	print "\n\nSee $file_out for results\n\n";
}


sub pry(){
	my $in_file = shift;
	my $out_file = shift;
	my $start = shift;
	my $stop = shift;

	# print "$in_file\n$out_file\n";

	my $flag;

	open INFILE, $in_file   or die "Cannot open input file to read from: $!";
	
	if($out_file =~ m/screen/i){
		*OUTFILE = *STDOUT;
	}else{
		open OUTFILE, ">$out_file" or die "Cannot open output file to read from: $!";
	}

	while(my $line = <INFILE>){
		chomp $line;
		next if $line =~ m/^\s*$/;   # Skip all blank and whitespace only lines

		if ($flag){
			if($line =~ m/$stop/){
				$flag = 0;
				print OUTFILE "CAPTURE ENDED AT: $line\n";
				next;
			}
			print OUTFILE "$line\n";
		}

		if($line =~ m/$start/){
			$flag = 1;
			print OUTFILE "\nCAPTURE STARTED AT: $line\n"
		}

	}

	close INFILE;
	return;
}
close OUTFILE;