#!/usr/bin/perl

use LWP::Simple;
use strict;
use Irssi;
use vars qw($VERSION %IRSSI);

my $feed = "";

%IRSSI = (
	authors => 'Rob Mitchelmore',
	contact => 'rob@midworld.co.uk',
	name => 'Currency Convertor Script',
	description => 'Converts currencies',
	license => 'Common sense, folks.  Share and enjoy.'
);

my $url = "http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml";

sub getcurr {
	my $content = get $url;
	if (!(defined $content)) {
		return 0;
		print "NO! NO! NO!";
	} else {
		return $content;
	}
}

sub getRate($$) {
	my $stuff = shift;
	my $currency = shift;
	if ($stuff =~ /<Cube currency='$currency' rate='([0-9\.]*)'\s*\/>/) {
		return $1;
	}
}

sub iterCurrs($) {
	my @fish = split /\n/, shift;
	my $currs = "";
	foreach (@fish) {
		if ($_ =~ /<Cube currency='([A-Z]*)' rate='[0-9\.]*'\s*\/>/) {
			if ($currs ne "") {
				$currs = $currs . ", " . $1;
			} else {
				$currs = $1;
			}
		}
	}
	return $currs;
}

sub toEuro($$$) {
	my $stuff = shift;
	my $currency = shift;
	my $amount = shift;

	my $rate = getRate($stuff, $currency);
	if ($rate != 0) {
		return $amount / getRate($stuff, $currency);
	} else {
		return 0;
	}
}

sub fromEuro($$$) {
	my $stuff = shift;
	my $currency = shift;
	my $amount = shift;

	return $amount * getRate($stuff, $currency);
}

sub fromto($$$$) {
	my $stuff = shift;
	my $from = shift;
	my $to = shift;
	my $amount = shift;

	$from =~ tr/[a-z]/[A-Z]/;
	$to =~ tr/[a-z]/[A-Z]/;

	my $val = $amount;
	if ($from ne "EUR") {
		$val = toEuro($stuff, $from, $amount);
	}
	if ($to ne "EUR") {
		$val = fromEuro($stuff, $to, $val);
	}
	return $val;
}

sub pt ($$) {
	my ($win, $data) = @_;
	if ($win) {
		$win->print($data);
	} else {
		Irssi::print($data);
	}
}

sub roundage($) {
	my $a = shift;
	return int($a * 1000) / 1000;
}

sub currconv {
	my ($data, $server, $win) = @_;

	my @whatever = split / /, $data;
	
	if (@whatever < 3) {
		pt $win, "Not enough parameters - requires <amount> <from> <to>";
	} else {
		my ($amount, $from, $to) = @whatever;
		my $result = roundage(fromto($feed, $from, $to, $amount));
		if (defined $result) {
			if ($amount == 0) {
				pt $win, "0 $from => 0 $to";
			} elsif ($result == 0) {
				pt $win, "This currency does not exist.  Use /curlist to get a list of available currencies.";
			} else {
				pt $win, "$amount $from => $result $to";
			}
		} else {
			pt $win, "Something's gone a bit wrong, possibly I don't know that currency.";
		}
	}
}

sub listcurrs {
	my ($data, $server, $win) = @_;
	pt $win, "Currencies available: " . iterCurrs($feed);
}

sub refresh {
	$feed = getcurr;
}

$feed = getcurr;

Irssi::command_bind cur => \&currconv;
Irssi::command_bind curlist => \&listcurrs;
Irssi::timeout_add(12 * 60 * 60 * 1000, \&refresh, undef);