Class::CSV - Class based CSV parser/writer

  use Class::CSV;

  my $csv = Class::CSV->parse(
    filename => 'test.csv',
    fields   => [qw/item qty sub_total/]
  );

  foreach my $line (@{$csv->lines()}) {
    $line->sub_total('$'. sprintf("%0.2f", $line->sub_total()));

    print 'Item:     '. $line->item(). "\n".
          'Qty:      '. $line->qty(). "\n".
          'SubTotal: '. $line->sub_total(). "\n";
  }

  my $cvs_as_string = $csv->string();

  $csv->print();

  my $csv = Class::CSV->new(
    fields         => [qw/userid username/],
    line_separator => "\r\n";
  );

  $csv->add_line([2063, 'testuser']);
  $csv->add_line({
    userid   => 2064,
    username => 'testuser2'
  });

# Class::CSV
#  Class Based CSV Parser/Writer
# Written by DJ <dj@boxen.net>
#
# $Id: CSV.pm,v 1.2 2005/03/07 02:43:48 david Exp $

# Class::CSV::Base
package Class::CSV::Base;

use strict;
use warnings;

BEGIN {
  ## Modules
  # Core
  use Carp qw/confess/;

  # Base
  use base qw(Class::Accessor);

  ## Constants
  use constant TRUE => 1;
  use constant FALSE => 0;

  ## Variables
  use vars qw($VERSION);
  $VERSION = do { my @r=(q$Revision: 1.3 $=~/\d+/g); sprintf "%d."."%02d"x$#r,@r};
}

sub _build_fields {
  my ($self, $fields) = @_;

  confess "Field list must be an array reference\n"
    unless (defined $fields and ref $fields eq 'ARRAY');

  $self->{_field_list} = $fields;

  # make the accessors via Class::Accessor
  __PACKAGE__->mk_accessors(@{$fields});

  foreach my $field (@{$fields}) {
    $self->{__fields}->{$field} = TRUE;
  }
}

sub set {
  my ($self, %items) = @_;

  foreach my $field (keys %items) {
    if (exists $self->{__fields}->{$field}) {
      $self->_set($field, $items{$field});
    } else {
      confess "Cannot set field: ". $field. " as it doesnt exist!\n";
    }
  }
}

sub _set {
  my ($self, $key, $value) = @_;

  return $self->{$key} = $value;
}

sub get {
  my ($self, @fields) = @_;

  # sanity check
  foreach my $field (@fields) {
    unless (exists $self->{__fields}->{$field}) {
      confess "Cannot get field: ". $field. " as it doesnt exist!\n";
    }
  }

  return $self->_get(@fields);
}

sub _get {
  my $self = shift;

  if(@_ == 1) {
    return $self->{$_[0]};
  } elsif( @_ > 1 ) {
    return @{$self}{@_};
  }

  return;
}

1;

# Class::CSV::CSV_XS_Options
package Class::CSV::CSV_XS_Options;

BEGIN {
  ## Modules
  # Core
  use Carp qw/confess/;

  ## Constants
  use constant TRUE => 1;
  use constant FALSE => 0;

  # Base
  use base qw(Class::CSV::Base);
}

sub new {
  my ($class, $opts) = @_;

  my $self = bless({}, $class);

  $self->_build_fields([qw/quote_char eol escape_char sep_char binary
                        types always_quote/]);

  if (defined $opts) {
    if (ref $opts eq 'HASH') {
      $self->set(%{$opts});
    } else {
      confess "Please provide csv_xs_options as a HASH ref!\n";
    }
  }

  return $self;
}

sub set {
  my ($self, %items) = @_;

  foreach my $field (keys %items) {
    unless (exists $self->{__fields}->{$field}) {
      $self->{__fields}->{$field} = TRUE;
      $self->mk_accessors($field);
    }
    $self->_set($field => $items{$field});
  }
}

sub to_hash_ref {
  my ($self) = @_;

  my $hash = {};
  foreach my $field (keys %{$self->{__fields}}) {
    my $value = $self->get($field);
    if (defined $value) {
      $hash->{$field} = $value;
    }
  }

  return $hash;
}

# Class::CSV::Line
package Class::CSV::Line;

BEGIN {
  ## Modules
  # Core
  use Carp qw/confess/;

  # CPAN
  use Text::CSV_XS;

  ## Constants
  use constant TRUE => 1;
  use constant FALSE => 0;

  # Base
  use base qw(Class::CSV::Base);
}

sub new {
  my ($class, %opts) = @_;

  confess "Please provide a list of fields\n"
    unless (exists $opts{fields});

  my $self = bless({}, $class);

  $self->{__csv_xs_options} = $opts{csv_xs_options};

  $self->_build_fields($opts{fields});
  $self->_do_parse($opts{line}) if (exists $opts{line});

  return $self;
}

sub parse {
  my ($class, %opts) = @_;

  confess "Please provide a line to parse\n"
    unless (exists $opts{line});

  my $self = $class->new(%opts);

  $self->_do_parse($opts{line});

  return $self;
}

sub _build_fields {
  my ($self, $fields) = @_;

  confess "Field list must be an array reference\n"
    unless (defined $fields and ref $fields eq 'ARRAY');

  $self->{_field_list} = $fields;

  # make the accessors via Class::Accessor
  __PACKAGE__->mk_accessors(@{$fields});

  foreach my $field (@{$fields}) {
    $self->{__fields}->{$field} = TRUE;
    $self->_set($field, undef);
  }
}

sub _do_parse {
  my ($self, $line) = @_;

  confess "Unable to find field array ref to build object with\n"
    unless (defined $self->{_field_list}
      and ref $self->{_field_list} eq 'ARRAY');

  my $csv = new Text::CSV_XS($self->{__csv_xs_options}->to_hash_ref());
  my $r = $csv->parse($line);
  if (defined $r and $r) {
    my @columns = $csv->fields();
    for (my $i = 0; $i < @columns; $i++) {
      $self->set(${$self->{_field_list}}[$i], $columns[$i]);
    }
  } else {
    if ($csv->error_input()) {
      confess "Failed to parse line: ". $csv->error_input(). "\n";
    } else {
      confess "Failed to parse line: unknown reason\n";
    }
  }
}

sub string {
  my ($self) = @_;

  confess "Uninitiated Line Objects cannot be converted to a string!\n"
    unless (exists $self->{_field_list}
    and ref $self->{_field_list} eq 'ARRAY');

  my @cols = ();
  foreach my $field (@{$self->{_field_list}}) {
    push(@cols, $self->_get($field));
  }

  my $csv = new Text::CSV_XS($self->{__csv_xs_options}->to_hash_ref());
  my $r = $csv->combine(@cols);
  if ($r) {
    return $csv->string();
  } else {
    confess "Failed to create CSV line from line: ". $csv->error_input(). "\n"
  }
}

1;


# Class::CSV
package Class::CSV;

BEGIN {
  ## Modules
  # Core
  use Carp qw/confess/;

  # Base
  use base qw(Class::CSV::Base);

  ## Constants
  use constant TRUE => 1;
  use constant FALSE => 0;

  use constant DEFAULT_LINE_SEPARATOR => "\n";

  ## Setup Accessors
  __PACKAGE__->mk_ro_accessors(qw(fields));
  __PACKAGE__->mk_accessors(qw(lines line_separator csv_xs_options));
}

sub new {
  my ($class, %opts) = @_;

  my $self = bless({}, $class);

  confess "Please provide an array ref of fields\n"
    unless (exists $opts{fields}
      and ref $opts{fields} eq 'ARRAY');

  $self->_private_set(
    line_separator  => $opts{line_separator} || DEFAULT_LINE_SEPARATOR,
    csv_xs_options  =>
      new Class::CSV::CSV_XS_Options($opts{csv_xs_options}),
    fields          => $opts{fields},
    lines           => []
  );

  return $self;
}

sub parse {
  my ($class, %opts) = @_;

  my $self = $class->new(%opts);

  if (exists $opts{classdbi_objects}) {
    $opts{objects} = $opts{classdbi_objects};
    delete($opts{classdbi_objects});
  }

  if (exists $opts{filename} or exists $opts{filehandle}) {
    $self->_do_parse(%opts);
  } elsif (exists $opts{objects}) {
    $self->_do_parse_objects(%opts);
  } else {
    confess "Please provide objects or a filename/filehandle to parse\n";
  }

  return $self;
}

sub _do_parse {
  my ($self, %opts) = @_;

  my @CSV_Content = ();
  if (exists $opts{'filename'} and defined $opts{'filename'}) {
    confess "Cannot find filename: ". $opts{'filename'}. "\n"
      unless (-f $opts{'filename'});
    confess "Cannot read filename: ". $opts{'filename'}. "\n"
      unless (-r $opts{'filename'});
    open(CSV, $opts{'filename'})
      or confess "Failed to open filename: ". $opts{'filename'}. ': '. $!. "\n";
    while (my $line = <CSV>) {
      push(@CSV_Content, $self->strip_crlf($line));
    }
    close(CSV);
  } elsif (exists $opts{'filehandle'} and defined $opts{'filehandle'}) {
    confess "filehandle provided is not a file handle\n"
      unless (defined(fileno($opts{'filehandle'})));
    my $fh = $opts{'filehandle'};
    while (my $line = <$fh>) {
      push(@CSV_Content, $self->strip_crlf($line));
    }
  } else {
    confess "Please provide a filename/filehandle to parse\n";
  }

  foreach my $line (@CSV_Content) {
    unless ($line and $line !~ /^([,"']|\s)+$/) {
      # Skip empty lines
      next;
    }
    push(@{$self->{lines}}, $self->new_line(undef, { line => $line }));
  }
}

sub _do_parse_objects {
  my ($self, %opts) = @_;

  confess "Please specify objects as an ARRAY ref!\n"
    unless (ref $opts{objects} eq 'ARRAY');

  foreach my $object (@{$opts{objects}}) {
    my $line = $self->new_line();

    foreach my $field (@{$self->fields()}) {
      confess ((ref $object). " does not contain method ". $field. "\n")
        unless ($object->can($field));

      $line->set( $field => $object->$field );
    }

    push(@{$self->{lines}}, $line);
  }
}

sub new_line {
  my ($self, $args, $opts) = @_;

  my %opts = ();
  if ($opts and ref $opts eq 'HASH') {
    %opts = %{$opts};
  }

  my $line = new Class::CSV::Line(
    fields         => $self->fields(),
    csv_xs_options => $self->csv_xs_options(),
    %opts
  );

  confess "Failed to create new line\n"
    unless ($line);

  if (defined $args) {
    if (ref $args eq 'ARRAY') {
      my @dr_array = @{$args};
      foreach my $field (@{$self->fields()}) {
        my $value = shift @dr_array;
        $line->set( $field => $value );
      }
    } elsif (ref $args eq 'HASH') {
      foreach my $field (keys %{$args}) {
        $line->set( $field => $args->{$field} );
      }
    } else {
      confess "Need the arguments passed as either an ARRAY ref or a HASH ref!\n";
    }
  }

  return $line;
}

sub add_line {
  my ($self, $args) = @_;

  confess "Cannot call add_line without an argument!\n"
    unless (defined $args and $args);

  my $line = $self->new_line($args);

  push(@{$self->{lines}}, $line);
}

sub string {
  my ($self) = @_;

  confess "No lines to write!\n" unless (ref $self->lines() eq 'ARRAY');

  my @string = ();
  map { push(@string, $_->string()); } @{$self->lines()};

  return join($self->line_separator(), @string). $self->line_separator();
}

sub print {
  my ($self) = @_;

  print $self->string();
}

sub strip_crlf {
  my ($self, $string) = @_;

  $string =~ s/[\n\r]+$//g;

  return $string;
}

sub _private_set {
  my ($self, %items) = @_;

  foreach my $field (keys %items) {
    $self->{$field} = $items{$field};
    $self->{__fields}->{$field} = TRUE;
  }
}

1;

__END__