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#############################################################################

# Pod/Usage.pm -- print usage messages for the running script.

#

# Copyright (C) 1996-2000 by Bradford Appleton. All rights reserved.

# This file is part of "PodParser". PodParser is free software;

# you can redistribute it and/or modify it under the same terms

# as Perl itself.

#############################################################################

package Pod::Usage;

use strict;

use vars qw($VERSION @ISA @EXPORT);

use JatsError;

$VERSION = '1.36';  ## Current version of this package

require  5.005;    ## requires this Perl version or later

=head1 NAME

Pod::Usage, pod2usage() - print a usage message from embedded pod documentation

=head1 SYNOPSIS

  use Pod::Usage

  my $message_text  = "This text precedes the usage message.";

  my $exit_status   = 2;          ## The exit status to use

  my $verbose_level = 0;          ## The verbose level to use

  my $filehandle    = \*STDERR;   ## The filehandle to write to

  pod2usage($message_text);

  pod2usage($exit_status);

  pod2usage( { -message => $message_text ,

               -exitval => $exit_status  ,  

               -verbose => $verbose_level,  

               -output  => $filehandle } );

  pod2usage(   -msg     => $message_text ,

               -exitval => $exit_status  ,  

               -verbose => $verbose_level,  

               -output  => $filehandle   );

  pod2usage(   -verbose => 2,

               -noperldoc => 1  )

=head1 ARGUMENTS

B<pod2usage> should be given either a single argument, or a list of

arguments corresponding to an associative array (a "hash"). When a single

argument is given, it should correspond to exactly one of the following:

=over 4

=item *

A string containing the text of a message to print I<before> printing

the usage message

=item *

A numeric value corresponding to the desired exit status

=item *

A reference to a hash

=back

If more than one argument is given then the entire argument list is

assumed to be a hash.  If a hash is supplied (either as a reference or

as a list) it should contain one or more elements with the following

keys:

=over 4

=item C<-message>

=item C<-msg>

The text of a message to print immediately prior to printing the

program's usage message. 

=item C<-exitval>

The desired exit status to pass to the B<exit()> function.

This should be an integer, or else the string "NOEXIT" to

indicate that control should simply be returned without

terminating the invoking process.

=item C<-verbose>

The desired level of "verboseness" to use when printing the usage

message. If the corresponding value is 0, then only the "SYNOPSIS"

section of the pod documentation is printed. If the corresponding value

is 1, then the "SYNOPSIS" section, along with any section entitled

"OPTIONS", "ARGUMENTS", or "OPTIONS AND ARGUMENTS" is printed.  If the

corresponding value is 2 or more then the entire manpage is printed.

The special verbosity level 99 requires to also specify the -sections

parameter; then these sections are extracted (see L<Pod::Select>)

and printed.

=item C<-sections>

A string representing a selection list for sections to be printed

when -verbose is set to 99, e.g. C<"NAME|SYNOPSIS|DESCRIPTION|VERSION">.

Alternatively, an array reference of section specifications can be used:

  pod2usage(-verbose => 99, 

            -sections => [ qw(fred fred/subsection) ] );

=item C<-output>

A reference to a filehandle, or the pathname of a file to which the

usage message should be written. The default is C<\*STDERR> unless the

exit value is less than 2 (in which case the default is C<\*STDOUT>).

=item C<-input>

A reference to a filehandle, or the pathname of a file from which the

invoking script's pod documentation should be read.  It defaults to the

file indicated by C<$0> (C<$PROGRAM_NAME> for users of F<English.pm>).

If you are calling B<pod2usage()> from a module and want to display

that module's POD, you can use this:

  use Pod::Find qw(pod_where);

  pod2usage( -input => pod_where({-inc => 1}, __PACKAGE__) );

=item C<-pathlist>

A list of directory paths. If the input file does not exist, then it

will be searched for in the given directory list (in the order the

directories appear in the list). It defaults to the list of directories

implied by C<$ENV{PATH}>. The list may be specified either by a reference

to an array, or by a string of directory paths which use the same path

separator as C<$ENV{PATH}> on your system (e.g., C<:> for Unix, C<;> for

MSWin32 and DOS).

=item C<-noperldoc>

By default, Pod::Usage will call L<perldoc> when -verbose >= 2 is

specified. This does not work well e.g. if the script was packed

with L<PAR>. The -noperldoc option suppresses the external call to

L<perldoc> and uses the simple text formatter (L<Pod::Text>) to 

output the POD.

=back

=head1 DESCRIPTION

B<pod2usage> will print a usage message for the invoking script (using

its embedded pod documentation) and then exit the script with the

desired exit status. The usage message printed may have any one of three

levels of "verboseness": If the verbose level is 0, then only a synopsis

is printed. If the verbose level is 1, then the synopsis is printed

along with a description (if present) of the command line options and

arguments. If the verbose level is 2, then the entire manual page is

printed.

Unless they are explicitly specified, the default values for the exit

status, verbose level, and output stream to use are determined as

follows:

=over 4

=item *

If neither the exit status nor the verbose level is specified, then the

default is to use an exit status of 2 with a verbose level of 0.

=item *

If an exit status I<is> specified but the verbose level is I<not>, then the

verbose level will default to 1 if the exit status is less than 2 and

will default to 0 otherwise.

=item *

If an exit status is I<not> specified but verbose level I<is> given, then

the exit status will default to 2 if the verbose level is 0 and will

default to 1 otherwise.

=item *

If the exit status used is less than 2, then output is printed on

C<STDOUT>.  Otherwise output is printed on C<STDERR>.

=back

Although the above may seem a bit confusing at first, it generally does

"the right thing" in most situations.  This determination of the default

values to use is based upon the following typical Unix conventions:

=over 4

=item *

An exit status of 0 implies "success". For example, B<diff(1)> exits

with a status of 0 if the two files have the same contents.

=item *

An exit status of 1 implies possibly abnormal, but non-defective, program

termination.  For example, B<grep(1)> exits with a status of 1 if

it did I<not> find a matching line for the given regular expression.

=item *

An exit status of 2 or more implies a fatal error. For example, B<ls(1)>

exits with a status of 2 if you specify an illegal (unknown) option on

the command line.

=item *

Usage messages issued as a result of bad command-line syntax should go

to C<STDERR>.  However, usage messages issued due to an explicit request

to print usage (like specifying B<-help> on the command line) should go

to C<STDOUT>, just in case the user wants to pipe the output to a pager

(such as B<more(1)>).

=item *

If program usage has been explicitly requested by the user, it is often

desirable to exit with a status of 1 (as opposed to 0) after issuing

the user-requested usage message.  It is also desirable to give a

more verbose description of program usage in this case.

=back

B<pod2usage> doesn't force the above conventions upon you, but it will

use them by default if you don't expressly tell it to do otherwise.  The

ability of B<pod2usage()> to accept a single number or a string makes it

convenient to use as an innocent looking error message handling function:

    use Pod::Usage;

    use Getopt::Long;

    ## Parse options

    GetOptions("help", "man", "flag1")  ||  pod2usage(2);

    pod2usage(1)  if ($opt_help);

    pod2usage(-verbose => 2)  if ($opt_man);

    ## Check for too many filenames

    pod2usage("$0: Too many files given.\n")  if (@ARGV > 1);

Some user's however may feel that the above "economy of expression" is

not particularly readable nor consistent and may instead choose to do

something more like the following:

    use Pod::Usage;

    use Getopt::Long;

    ## Parse options

    GetOptions("help", "man", "flag1")  ||  pod2usage(-verbose => 0);

    pod2usage(-verbose => 1)  if ($opt_help);

    pod2usage(-verbose => 2)  if ($opt_man);

    ## Check for too many filenames

    pod2usage(-verbose => 2, -message => "$0: Too many files given.\n")

        if (@ARGV > 1);

As with all things in Perl, I<there's more than one way to do it>, and

B<pod2usage()> adheres to this philosophy.  If you are interested in

seeing a number of different ways to invoke B<pod2usage> (although by no

means exhaustive), please refer to L<"EXAMPLES">.

=head1 EXAMPLES

Each of the following invocations of C<pod2usage()> will print just the

"SYNOPSIS" section to C<STDERR> and will exit with a status of 2:

    pod2usage();

    pod2usage(2);

    pod2usage(-verbose => 0);

    pod2usage(-exitval => 2);

    pod2usage({-exitval => 2, -output => \*STDERR});

    pod2usage({-verbose => 0, -output  => \*STDERR});

    pod2usage(-exitval => 2, -verbose => 0);

    pod2usage(-exitval => 2, -verbose => 0, -output => \*STDERR);

Each of the following invocations of C<pod2usage()> will print a message

of "Syntax error." (followed by a newline) to C<STDERR>, immediately

followed by just the "SYNOPSIS" section (also printed to C<STDERR>) and

will exit with a status of 2:

    pod2usage("Syntax error.");

    pod2usage(-message => "Syntax error.", -verbose => 0);

    pod2usage(-msg  => "Syntax error.", -exitval => 2);

    pod2usage({-msg => "Syntax error.", -exitval => 2, -output => \*STDERR});

    pod2usage({-msg => "Syntax error.", -verbose => 0, -output => \*STDERR});

    pod2usage(-msg  => "Syntax error.", -exitval => 2, -verbose => 0);

    pod2usage(-message => "Syntax error.",

              -exitval => 2,

              -verbose => 0,

              -output  => \*STDERR);

Each of the following invocations of C<pod2usage()> will print the

"SYNOPSIS" section and any "OPTIONS" and/or "ARGUMENTS" sections to

C<STDOUT> and will exit with a status of 1:

    pod2usage(1);

    pod2usage(-verbose => 1);

    pod2usage(-exitval => 1);

    pod2usage({-exitval => 1, -output => \*STDOUT});

    pod2usage({-verbose => 1, -output => \*STDOUT});

    pod2usage(-exitval => 1, -verbose => 1);

    pod2usage(-exitval => 1, -verbose => 1, -output => \*STDOUT});

Each of the following invocations of C<pod2usage()> will print the

entire manual page to C<STDOUT> and will exit with a status of 1:

    pod2usage(-verbose  => 2);

    pod2usage({-verbose => 2, -output => \*STDOUT});

    pod2usage(-exitval  => 1, -verbose => 2);

    pod2usage({-exitval => 1, -verbose => 2, -output => \*STDOUT});

=head2 Recommended Use

Most scripts should print some type of usage message to C<STDERR> when a

command line syntax error is detected. They should also provide an

option (usually C<-H> or C<-help>) to print a (possibly more verbose)

usage message to C<STDOUT>. Some scripts may even wish to go so far as to

provide a means of printing their complete documentation to C<STDOUT>

(perhaps by allowing a C<-man> option). The following complete example

uses B<Pod::Usage> in combination with B<Getopt::Long> to do all of these

things:

    use Getopt::Long;

    use Pod::Usage;

    my $man = 0;

    my $help = 0;

    ## Parse options and print usage if there is a syntax error,

    ## or if usage was explicitly requested.

    GetOptions('help|?' => \$help, man => \$man) or pod2usage(2);

    pod2usage(1) if $help;

    pod2usage(-verbose => 2) if $man;

    ## If no arguments were given, then allow STDIN to be used only

    ## if it's not connected to a terminal (otherwise print usage)

    pod2usage("$0: No files given.")  if ((@ARGV == 0) && (-t STDIN));

    __END__

    =head1 NAME

    sample - Using GetOpt::Long and Pod::Usage

    =head1 SYNOPSIS

    sample [options] [file ...]

     Options:

       -help            brief help message

       -man             full documentation

    =head1 OPTIONS

    =over 8

    =item B<-help>

    Print a brief help message and exits.

    =item B<-man>

    Prints the manual page and exits.

    =back

    =head1 DESCRIPTION

    B<This program> will read the given input file(s) and do something

    useful with the contents thereof.

    =cut

=head1 CAVEATS

By default, B<pod2usage()> will use C<$0> as the path to the pod input

file.  Unfortunately, not all systems on which Perl runs will set C<$0>

properly (although if C<$0> isn't found, B<pod2usage()> will search

C<$ENV{PATH}> or else the list specified by the C<-pathlist> option).

If this is the case for your system, you may need to explicitly specify

the path to the pod docs for the invoking script using something

similar to the following:

    pod2usage(-exitval => 2, -input => "/path/to/your/pod/docs");

In the pathological case that a script is called via a relative path

I<and> the script itself changes the current working directory

(see L<perlfunc/chdir>) I<before> calling pod2usage, Pod::Usage will

fail even on robust platforms. Don't do that.

=head1 AUTHOR

Please report bugs using L<http://rt.cpan.org>.

Marek Rouchal E<lt>marekr@cpan.orgE<gt>

Brad Appleton E<lt>bradapp@enteract.comE<gt>

Based on code for B<Pod::Text::pod2text()> written by

Tom Christiansen E<lt>tchrist@mox.perl.comE<gt>

=head1 ACKNOWLEDGMENTS

Steven McDougall E<lt>swmcd@world.std.comE<gt> for his help and patience

with re-writing this manpage.

=head1 SEE ALSO

L<Pod::Parser>, L<Getopt::Long>, L<Pod::Find>

=cut

#############################################################################

#use diagnostics;

use Carp;

use Config;

use Exporter;

use File::Spec;

@EXPORT = qw(&pod2usage);

BEGIN {

       require Pod::PlainText;

       @ISA = qw( Pod::PlainText );

}

require Pod::Select;

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

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

## Function definitions begin here

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

sub pod2usage {

    local($_) = shift;

    my %opts ;

    ## Collect arguments

    if (@_ > 0) {

        ## Too many arguments - assume that this is a hash and

        ## the user forgot to pass a reference to it.

        %opts = ($_, @_);

    }

    elsif (!defined $_) {

      $_ = '';

    }

    elsif (ref $_) {

        ## User passed a ref to a hash

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

    }

    elsif (/^[-+]?\d+$/) {

        ## User passed in the exit value to use

        $opts{'-exitval'} =  $_;

    }

    else {

        ## User passed in a message to print before issuing usage.

        $_  and  $opts{'-message'} = $_;

    }

    #

    #   Defaults

    #   Don't use perldoc - it creates different output

    #

    $opts{-noperldoc} ||= 1;

    ## Need this for backward compatibility since we formerly used

    ## options that were all uppercase words rather than ones that

    ## looked like Unix command-line options.

    ## to be uppercase keywords)

    %opts = map {

        my ($key, $val) = ($_, $opts{$_});

        $key =~ s/^(?=\w)/-/;

        $key =~ /^-msg/i   and  $key = '-message';

        $key =~ /^-exit/i  and  $key = '-exitval';

        lc($key) => $val;

    } (keys %opts);

    ## Now determine default -exitval and -verbose values to use

    if ((! defined $opts{'-exitval'}) && (! defined $opts{'-verbose'})) {

        $opts{'-exitval'} = 2;

        $opts{'-verbose'} = 0;

    }

    elsif (! defined $opts{'-exitval'}) {

        $opts{'-exitval'} = ($opts{'-verbose'} > 0) ? 1 : 2;

    }

    elsif (! defined $opts{'-verbose'}) {

        $opts{'-verbose'} = (lc($opts{'-exitval'}) eq 'noexit' ||

                             $opts{'-exitval'} < 2);

    }

    ## Default the output file

    $opts{'-output'} = (lc($opts{'-exitval'}) eq 'noexit' ||

                        $opts{'-exitval'} < 2) ? \*STDOUT : \*STDERR

            unless (defined $opts{'-output'});

    ## Default the input file

    $opts{'-input'} = $0  unless (defined $opts{'-input'});

    ## Look up input file in path if it doesnt exist.

    unless ((ref $opts{'-input'}) || (-e $opts{'-input'})) {

        my $basename = $opts{'-input'};

        my $pathsep = ($^O =~ /^(?:dos|os2|MSWin32)$/i) ? ';'

                            : (($^O eq 'MacOS' || $^O eq 'VMS') ? ',' :  ':');

        my $pathspec = $opts{'-pathlist'} || $ENV{PATH} || $ENV{PERL5LIB};

        my @paths = (ref $pathspec) ? @$pathspec : split($pathsep, $pathspec);

        for my $dirname (@paths) {

            $_ = File::Spec->catfile($dirname, $basename)  if length;

            last if (-e $_) && ($opts{'-input'} = $_);

        }

    }

    ## Now create a pod reader and constrain it to the desired sections.

    my $parser = new Pod::Usage(USAGE_OPTIONS => \%opts);

    if ($opts{'-verbose'} == 0) {

        $parser->select('(?:SYNOPSIS|USAGE)\s*');

    }

    elsif ($opts{'-verbose'} == 1) {

        my $opt_re = '(?i)' .

                     '(?:OPTIONS|ARGUMENTS)' .

                     '(?:\s*(?:AND|\/)\s*(?:OPTIONS|ARGUMENTS))?';

        $parser->select( '(?:SYNOPSIS|USAGE)\s*', $opt_re, "DESCRIPTION/$opt_re" );

    }

    elsif ($opts{'-verbose'} >= 2 && $opts{'-verbose'} != 99) {

        $parser->select('.*');

    }

    elsif ($opts{'-verbose'} == 99) {

        my $sections = $opts{'-sections'};

        $parser->select( (ref $sections) ? @$sections : $sections );

        $opts{'-verbose'} = 1;

    }

    ## Now translate the pod document and then exit with the desired status

    if (      !$opts{'-noperldoc'}

         and  $opts{'-verbose'} >= 2

         and  !ref($opts{'-input'})

         and  $opts{'-output'} == \*STDOUT )

    {

       ## spit out the entire PODs. Might as well invoke perldoc

       my $progpath = File::Spec->catfile($Config{scriptdir}, 'perldoc');

       print { $opts{'-output'} } ($opts{'-message'}, "\n") if($opts{'-message'});

       if(defined $opts{-input} && $opts{-input} =~ /^\s*(\S.*?)\s*$/) {

         # the perldocs back to 5.005 should all have -F

	 # without -F there are warnings in -T scripts

         system($progpath, '-F', $1);

         if($?) {

           # RT16091: fall back to more if perldoc failed

           system(($Config{pager} || $ENV{PAGER} || '/bin/more'), $1);

         }

       } else {

         croak "Unspecified input file or insecure argument.\n";

       }

    }

    else {

       $parser->parse_from_file($opts{'-input'}, $opts{'-output'});

    }

    exit($opts{'-exitval'})  unless (lc($opts{'-exitval'}) eq 'noexit');

}

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

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

## Method definitions begin here

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

sub new {

    my $this = shift;

    my $class = ref($this) || $this;

    my %params = @_;

    my $self = {%params};

    bless $self, $class;

    if ($self->can('initialize')) {

        $self->initialize();

    } else {

        $self = $self->SUPER::new();

        %$self = (%$self, %params);

    }

    return $self;

}

sub select {

    my ($self, @sections) = @_;

    if ($ISA[0]->can('select')) {

        $self->SUPER::select(@sections);

    } else {

        # we're using Pod::Simple - need to mimic the behavior of Pod::Select

        my $add = ($sections[0] eq '+') ? shift(@sections) : '';

        ## Reset the set of sections to use

        unless (@sections) {

          delete $self->{USAGE_SELECT} unless ($add);

          return;

        }

        $self->{USAGE_SELECT} = []

          unless ($add && $self->{USAGE_SELECT});

        my $sref = $self->{USAGE_SELECT};

        ## Compile each spec

        for my $spec (@sections) {

          my $cs = Pod::Select::_compile_section_spec($spec);

          if ( defined $cs ) {

            ## Store them in our sections array

            push(@$sref, $cs);

          } else {

            carp qq{Ignoring section spec "$spec"!\n};

          }

        }

    }

}

# Override Pod::Text->seq_i to return just "arg", not "*arg*".

sub seq_i { return $_[1] }

# This overrides the Pod::Text method to do something very akin to what

# Pod::Select did as well as the work done below by preprocess_paragraph.

# Note that the below is very, very specific to Pod::Text.

sub _handle_element_end {

    my ($self, $element) = @_;

    if ($element eq 'head1') {

        $self->{USAGE_HEADINGS} = [ $$self{PENDING}[-1][1] ];

        if ($self->{USAGE_OPTIONS}->{-verbose} < 2) {

            $$self{PENDING}[-1][1] =~ s/^\s*SYNOPSIS\s*$/USAGE/;

        }

    } elsif ($element =~ /^head(\d+)$/ && $1) { # avoid 0

        my $idx = $1 - 1;

        $self->{USAGE_HEADINGS} = [] unless($self->{USAGE_HEADINGS});

        $self->{USAGE_HEADINGS}->[$idx] = $$self{PENDING}[-1][1];

    }

    if ($element =~ /^head\d+$/) {

        $$self{USAGE_SKIPPING} = 1;

        if (!$$self{USAGE_SELECT} || !@{ $$self{USAGE_SELECT} }) {

            $$self{USAGE_SKIPPING} = 0;

        } else {

            my @headings = @{$$self{USAGE_HEADINGS}};

            for my $section_spec ( @{$$self{USAGE_SELECT}} ) {

                my $match = 1;

                for (my $i = 0; $i < $Pod::Select::MAX_HEADING_LEVEL; ++$i) {

                    $headings[$i] = '' unless defined $headings[$i];

                    my $regex   = $section_spec->[$i];

                    my $negated = ($regex =~ s/^\!//);

                    $match  &= ($negated ? ($headings[$i] !~ /${regex}/)

                                         : ($headings[$i] =~ /${regex}/));

                    last unless ($match);

                } # end heading levels

                if ($match) {

                  $$self{USAGE_SKIPPING} = 0;

                  last;

                }

            } # end sections

        }

        # Try to do some lowercasing instead of all-caps in headings, and use

        # a colon to end all headings.

        if($self->{USAGE_OPTIONS}->{-verbose} < 2) {

            local $_ = $$self{PENDING}[-1][1];

            s{([A-Z])([A-Z]+)}{((length($2) > 2) ? $1 : lc($1)) . lc($2)}ge;

            s/\s*$/:/  unless (/:\s*$/);

            $_ .= "\n";

            $$self{PENDING}[-1][1] = $_;

        }

    }

    if ($$self{USAGE_SKIPPING} && $element !~ m/^over-/) {

        pop @{ $$self{PENDING} };

    } else {

        $self->SUPER::_handle_element_end($element);

    }

}

# required for Pod::Simple API

sub start_document {

    my $self = shift;

    $self->SUPER::start_document();

    my $msg = $self->{USAGE_OPTIONS}->{-message}  or  return 1;

    my $out_fh = $self->output_fh();

    print $out_fh "$msg\n";

}

# required for old Pod::Parser API

sub begin_pod {

    my $self = shift;

    $self->SUPER::begin_pod();  ## Have to call superclass

    my $msg = $self->{USAGE_OPTIONS}->{-message}  or  return 1;

    my $out_fh = $self->output_handle();

    print $out_fh "$msg\n";

}

sub preprocess_paragraph {

    my $self = shift;

    local $_ = shift;

    my $line = shift;

    ## See if this is a heading and we arent printing the entire manpage.

    if (($self->{USAGE_OPTIONS}->{-verbose} < 2) && /^=head/) {

        ## Change the title of the SYNOPSIS section to USAGE

        s/^=head1\s+SYNOPSIS\s*$/=head1 USAGE/;

        ## Try to do some lowercasing instead of all-caps in headings

        s{([A-Z])([A-Z]+)}{((length($2) > 2) ? $1 : lc($1)) . lc($2)}ge;

        ## Use a colon to end all headings

        s/\s*$/:/  unless (/:\s*$/);

        $_ .= "\n";

    }

    return  $self->SUPER::preprocess_paragraph($_);

}

1; # keep require happy