#!/usr/bin/perl
#
# Srijith K. Nair (http://srijith.net)
#
# Perl script to send expense to Clearcheckbook's GMail/XMPP Bot
# Now with offline support!
#
# Note that this does not support transactions like 'bal' which requires 
# a reply from the Bot since the Net::XMPP::Client->MessageSend doesn't 
# seem to handle responses!
#
# Copyright: Perl Artistic License 2.0
# http://www.opensource.org/licenses/artistic-license-2.0.php
#
# Version : 1.0
# Release : 06-Nov-2007

use strict;
use Net::XMPP;
use Getopt::Std;

############## Configuration ####################

my $username = ""; # don't add 'gmail.com'
my $password = "";
my $offlineFile = '/home/username/.offline-b4b';

my $componentname = 'gmail.com';
my $to = "clearcheckbot";
my $resource = "Bot4Bot";
my $DEBUG = 0;
my $XMPP_DEBUG = 0;

############ End of configuration #################

my %options=();
getopts("osh",\%options);
my $msg = $ARGV[0];

if($options{'h'}) {
	&usage();
	exit(0);
}elsif (($msg eq "") and !($options{'s'})) {
	print "Wrong input\n\n";
	&usage();
	exit(0);
}

if ($options{'o'} and $options{'s'}) {
	print "You cannot set both 'offline' and 'sync' mode at the same time. Exiting!\n";
	exit(0);
}

my $datetime = localtime();

if ($options{'o'}) {
	print "DEBUG: offline mode set\n" if $DEBUG;
	print "Adding to offline file ...";
	&addEntry($msg);
	print "Done!\n";
	exit(1);
}

my $Connection = new Net::XMPP::Client(debuglevel=>$XMPP_DEBUG,debugfile=>"stdout");
my $status = &connAuth();

if (!($options{'s'})) {
	# Send message
	my @result= $Connection->MessageSend(
       to => "$to\@$componentname", body => $msg,
       resource => $resource);
	if($result[0] == 0) {
		print "Successful sent transaction!\n";
	}
	else {
		print "There was some error. Try again!\n";
		exit(0);
	}
}
else {
	print "DEBUG: sync mode set\n" if $DEBUG;
}

&sendOfflineContent();


#-------------------------- subroutines -----------------------------#

sub addEntry {
	my $newTran = shift;
	open(FILE,">>$offlineFile") || die("Cannot open offline file $offlineFile");
	print FILE "$newTran on $datetime\n"; #Bot does not support time field so we need to add it to description
	close (FILE);
	print "DEBUG: '$newTran' added to offline file\n" if $DEBUG;
}

sub promptUser {

   # two possible input arguments - $promptString, and $defaultValue
   my ($promptString,$defaultValue) = @_;

   if ($defaultValue) {
      print $promptString, "[", $defaultValue, "]: ";
   } else {
      print $promptString, ": ";
   }

   $| = 1;               # force a flush after our print
   $_ = <STDIN>;         # get the input from STDIN (presumably the keyboard)
   chomp;

   #-----------------------------------------------------------------#
   #  if we had a $default value, and the user gave us input, then   #
   #  return the input; if we had a default, and they gave us no     #
   #  no input, return the $defaultValue.                            #
   #                                                                 # 
   #  if we did not have a default value, then just return whatever  #
   #  the user gave us.  if they just hit the <enter> key,           #
   #  the calling routine will have to deal with that.               #
   #-----------------------------------------------------------------#

   if ("$defaultValue") {
      return $_ ? $_ : $defaultValue;    # return $_ if it has a value
   } else {
      return $_;
   }
}

sub sendOfflineContent {
	open(FILE, "<$offlineFile");
	my @rawData=<FILE>;
	close(FILE);
	my $index=0;
	my @result;
	if($rawData[0]) {
		print "You have old offline data. Let me send it. Hold on *";
		while($rawData[0]) {
			@result= $Connection->MessageSend(
       				to => "$to\@$componentname", body => $rawData[0],
       				resource => $resource);
			if($result[0] != 0) {
				print "There was some error. Saving unsent data!\n";
				open(FILE, ">$offlineFile");
				print FILE @rawData;
				close FILE;
				exit(0);
			}
			print "DEBUG: Sent $rawData[0]" if $DEBUG;
			print "*";sleep 1;
			splice(@rawData, 0, 1);
		}
		print " Done\n";
		open(FILE, ">$offlineFile");
		print FILE @rawData;
		close FILE;
	}
	else {
		print "No offline data to send!\n";
	}
}


sub connAuth{

	# Google Talk parameters
	my $hostname = 'talk.google.com';
	my $port = 5222;
	my $connectiontype = 'tcpip';
	my $tls = 1;
	my $timeout = 10;

	# Connect
	my $status = $Connection->Connect(
      hostname => $hostname, 
	   port => $port,
      componentname => $componentname,
      connectiontype => $connectiontype, 
	   tls => $tls,
	   timeout => $timeout);

	if (!(defined($status)) and !($options{'s'})) {
	   print "ERROR:  Connection failed.\n";
	   print "DEBUG:        ($!)\n" if $DEBUG;
	   my $useOffline = &promptUser("Resort to Offline mode? (y/n) ","y");
		if($useOffline eq 'y') {
	   	addEntry($msg);
			print ("Appened transaction to offline file. Will send it over the next you call me, if we are back online.\n");
			exit(1);
		} elsif ($useOffline eq 'n') {
			exit(0);	
		}
	} elsif(!(defined($status))) {
		print "Connection Error. Sync Failed\n";
		exit(0);
	}

	# Change hostname
	my $sid = $Connection->{SESSION}->{id};
	$Connection->{STREAM}->{SIDS}->{$sid}->{hostname} = $componentname;

	# Authenticate
	my @result = $Connection->AuthSend(
       username => $username, password => $password,
       resource => $resource);

	if ($result[0] ne "ok") {
   	print "ERROR: Authorization failed: $result[0] - $result[1]\n";
   	exit(0);
	}
}

sub usage() {
	print "Usage:\n";
	print "$0 [-o -s] [transaction]\n\n";
	print "Invoked without -o or -s, the script sends specified transaction to Clearcheckbook.com\n"; 
	print "and also uploads older locally stored transactions. Note that the transaction string should\n";
	print "be enclosed in a single quote. For example: $0 'w 5.61 ck f subway sandwich' \n\n";
	print "-o\tOffline mode. New transaction is added into local file for synchronisation later.\n";
	print "-s\tSend transactions stored in offline file. Does not expect new transaction.\n";
}