package Configuration;

=head1 NAME

Configuration -- An object that keeps track of the program configuration.

=head1 SYNOPSIS

my $configuration = Configuration->new;
my $boolean = Configuration->save;

Object hash entries:
  project_array         array of strings

=head1 DESCRIPTION

This object keeps track of the program configuration.

=head1 VERSION

0.001 (last update:  6/30/04)

=head1 AUTHOR

Chet Langin, clangin@siu.edu

SIU Plant Biotechnology and Genomics Core-facility

=head1 BUGS

None known.

=head1 SEE ALSO

extropy ExtropyConstants ExtropyUtils Extropy::MenuMain

=head1 COPYRIGHT

Copyright 2004, Chet Langin, All Rights Reserved.

This program is free software.  You may copy or
redistribute it under the same terms as Perl itself.

=head1 METHODS

The remainder of this document describes the methods available to the
programmer.

=cut

# load the pragmas
use warnings;
use strict;

# load other modules
use ExtropyConstants;
use ExtropyUtils;

# package variables
my $kbd_input_line = "";
# my $project_name = "";

# ********************************  new  ******************************

=head2 new

  Configuration->new;

Creates an instance of the Configuration object.

=cut

# ---------------------------------------------------------------------

sub new {
  # instantiate the oject
  my $self = {};
  bless $self;
  my $defined = TRUE;

  # see if a configuation file exists
  my $config_file_exists = TRUE;
  my $config_file_created = TRUE;
  open(CONF_FILE, "<", "extropy.cfg")
    or $config_file_exists = FALSE;

  if($config_file_exists) {
    my @project_array = ();
    # read the configuration file
    my @file_array = <CONF_FILE>;
    for(my $lcv = 0; $lcv < scalar(@file_array); $lcv++) {
      my $current_line = $file_array[$lcv];
      next if($current_line =~ /^#/);
      chomp $current_line;
      next if($current_line =~ /^\s*$/);
      my @line_array = split /=/, $current_line;
      if($line_array[0] =~ /project/) {
        push(@{$self->{project_array}}, $line_array[1]);
      } # if
    } # for
    close CONF_FILE;
  } # if
  else {
    # config file does not exist
    # try to create a configuration file
    $self->{project_exists} = FALSE;
    @{$self->{project_array}} = [];
    message_start;
    message("The \"extropy.cfg\" configuration file could not be opened:");
    message("  $!.");
    message("Creating an \"extropy.cfg\" file...");
    open(CONF_FILE, ">", "extropy.cfg")
      or $config_file_created = FALSE;
    if($config_file_created) {
      message("\"extropy.cfg\" file created.");
      close CONF_FILE;
    } # if
    else {
      message("extropy.cfg file could not be created:  $!");
      message("extropy cannot continue without an extropy.cfg file.");
      message("extropy is terminating...");
      blank_line;
      $defined = FALSE;
    } # else
  } # if

  # return values
  if($defined) {
    $self;
  } # if
  else {
    undef;
  } # else
} # new()

# ********************************  save  *****************************

=head2 save

  Configuration->save;

Saves the configuration to the extropy.cfg file.

=cut

# ---------------------------------------------------------------------

sub save {
  my $self = shift;
  my $project = shift;
  my $error = FALSE;

  open(CFG_FILE, ">", "extropy.cfg")
    or $error = TRUE;
  if($error) {
    message("Could not save to extropy.cfg");
    message("$!");
  } # if
  else {
    print CFG_FILE "# extropy.cfg\n";
    print CFG_FILE "# This is the configuration file for the program extropy.\n";
    print CFG_FILE "# This file is created automatically by extropy.\n";
    print CFG_FILE "# Any changes made directly to this file may be lost.\n";
    my $date = localtime;
    print CFG_FILE "# Last update:  $date\n\n";
    foreach my $project (@{$self->{project_array}}) {
      print CFG_FILE "project=$project\n";
    } # foreach
    message("The program configuration was saved to extropy.cfg");
  } # else
  close CFG_FILE;

  $project->save;

} # save

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