#! /usr/bin/perl

#
# FXController
# the controller for the FX Arbitrage appliation
# mediates interaction between the Model (FXEngine, FXData)
# and the View (index.pl)
# 
#

package FXController;

use FXData;
use FXSessionManager;
use FXEngine;
use strict;

# constructor FXController(FXSession object)
sub new {
    my $class = shift;
    my $self = {};

    $self->{fxsession} = shift;
    $self->{fxdata}    = undef; 
    $self->{limit}     = 5; 

    bless ($self, $class);
    
    $self->_initialize();
    
    return $self;
}

# instantiates FXData object
sub _initialize {
    my $self = shift;
    $self->{fxdata} = $self->{fxsession}->fxdata_factory();
}

# udpates currency data using FXData
sub update_data {
    my $self = shift;
    $self->{fxdata}->sync_rates();
}


#
# Public Methods
#

# currency_listing()
# returns a hash of currency symbols and their descriptions
# available to the user.  
# { SYMBOL1 => DESCRIPTION1, ... } 
sub currency_listing {
    my $self = shift;
    return %{$self->{fxdata}->currency_listing()};   
}

# do_update(bool)
# if true updates currency data 
sub do_update {
    my $self = shift;
    my $bool = shift;
    $self->update_data() if $bool;
}

# set_table_limit(int)
# determines the size of the 
# arbitrage table listing given to the view
sub set_table_limit {
    my $self = shift;
    $self->{limit} = shift;
}

# arbitrage_table(start, array) -> string
# start - the currency that starts every currency transaction
# array - array of currency symbols used in the arbitrage table
# returns a string of possible fx arbitrage transactions.
sub aribitrage_table {
    my $self = shift;
    my $start = shift;
    my @currencies = @_;

    @currencies = grep { $_ ne $start } @currencies;
    unshift @currencies, $start;
    
    my $fxe = new FXEngine($self->{fxdata}, \@currencies);
    $fxe->set_limit($self->{limit}-1);
    return join "<br>", $fxe->get_transactions();
}


1;