#!/usr/bin/perl

pp_addpm({At=>Top},<<'EOD');

$PDL::onlinedoc->scan(__FILE__) if $PDL::onlinedoc;

=head1 NAME

PDL::GSL::CDF - PDL interface to GSL Cumulative Distribution Functions

=head1 DESCRIPTION

This is an interface to the Cumulative Distribution Function package present in the GNU Scientific Library. 

=head1 SYNOPSIS

    use PDL;
    use PDL::GSL::CDF;

    my $p = gsl_cdf_tdist_P( $t, $df );

    my $t = gsl_cdf_tdist_Pinv( $p, $df );

=cut

EOD

pp_addhdr('
#include <gsl/gsl_cdf.h>

');

my ($header) = `gsl-config --cflags` =~ m/-I(.+)$/;
$header .= '/gsl/gsl_cdf.h';
# for win32. Thanks Sisyphus!
$header =~ s/"//g;

open my $fh, "< $header" or die "$!";

local $/ = undef;
my $h = <$fh>;
my @functions = $h =~ m/\n(double .+? ;)\n/xmsg;

my %p_type = (
  'double'       => 'double',
  'unsigned int' => 'ushort',
);

for (@functions) {
  s/\n\s+/ /xmsg;
  s/const //g;
  if (m/^(\w+)\ (\w+)\ \( (.+) \)\;$/xs) {
    my ($out_type, $function, $pars) = ($1, $2, $3);
    my @pars = split /,/, $pars;
    for (@pars) {
      if (m/^(.+)( \w+)$/) {
        my ($type, $par) = ($1, $2);
        s/^ | $//g for ($type, $par);
        $par = lc $par;
          # numbers interfere with $ISGOOD in BadCode
        $par =~ s/1/a/g;
        $par =~ s/2/b/g;
        $_ = [$p_type{$type}, $par];
      }
    }
    my ($p, $code, $badcode) = print_ppdef( $out_type, $function, @pars );
    pp_def($function,
      HandleBad => 1,
      GenericTypes => [D],
      Pars => $p,
      Code => $code,
      BadCode => $badcode,
      Doc  => '',
    );
  }
}

sub print_ppdef {
  my ($out_type, $function, @pars) = @_;
 
  my ($pars, $code, $badcode);

  for (@pars) {
    my ($type, $par) = @$_;
    $pars .= "$type $par(); ";
  }
  $pars .= "$out [o]out()";

  $code = "\$out() = $function( ";
  $code .= "\$" . $_->[1] . "(), "
    for (@pars);
  $code .= ");";
  $code =~ s/, \);/ );/;

  $badcode
    = "if ( " . join(' && ', map { "\$ISGOOD($_->[1]())" } @pars ) . " ) {\n";
  $badcode .= '  ' . $code . "\n}\n";
  $badcode .= "else {\n  \$SETBAD(out());\n}";
 
#  print "pp_def('$function',\n";
#  print "  HandleBad => 1,\n";
#  print "  GenericTypes => [D],\n";
#  print "  Pars => '$pars',\n";
#  print "  Code => '\n$code\n',\n";
#  print "  BadCode => '\n$badcode\n',\n";
#  print "  Doc  => '',\n";
#  print ");\n\n";
  return ($pars, $code, $badcode);
}

pp_addpm({At=>Bot},<<'EOD');

=head1 AUTHOR

Copyright (C) 2009 Maggie J. Xiong <maggiexyz users.sourceforge.net>

The GSL CDF module was written by J. Stover.

All rights reserved. There is no warranty. You are allowed to redistribute this software / documentation as described in the file COPYING in the PDL distribution.

=cut

EOD

pp_done();