#!/usr/bin/perl
use warnings;
use strict;

use Config;
use Perldoc::Search;
use Shell::POSIX::Select;
use File::Basename;
use Getopt::Std;
use Pod::Simple::TextContent;

our $LESS = "/usr/bin/less";

getopts("u", \my %opts);

my $searcher = Perldoc::Search->new();

if($opts{u}) {
    print "This will take a couple of minutes, please stand by.\n";
    $searcher->update();
    print "Done\n";
} elsif(@ARGV) {
    search();
}

###########################################
sub search {
###########################################

    # Search documents containing both "swish" and "install"
    my @hits = $searcher->search("@ARGV");

    if ( !@hits ) {
        print "No Results\n";
        return;
    }

    my @select  = ();
    my %map     = ();

        # Shut up the goofy  Shell::POSIX::Select implementation
    our($Eof, $Reply);

    for my $hit (@hits) {
        if(! defined $hit) {
            die "Before searching, please run the indexer: perldig -u\n";
        }
        my $path = my $org_path = $hit->path();
        $path = $searcher->relative($path);
        push @select, $path;
        $map{$path} = $org_path;
    }

    @select = sort @select;

    select my $file (@select) {
        system "$LESS $map{$file}";
        last;
    }
}

__END__

=head1 NAME

    perldig - Dig up keywords in the local Perl documentation

=head1 SYNOPSIS

       # Update the index (required before first start)
    perldig -u

       # Search for a keyword
    perldig keyword(s)

=head1 DESCRIPTION

When using C<perldig> for the first time, a new index needs to be
created. Just call

    $ perldig -u

and everything happens automatically: A crawler will detect locally
installed Perl documentation pages, rummage through the POD and index
them. When this initial run has been completed, C<perldig> is ready to
process search requests:

  $ perldig frobnicate

  1) pod/perlguts.pod    2) pod/perlxstut.pod   3) pod/perlnewmod.pod

  Enter number of choice: 

The command above shows a search for the keyword C<frobnicate>. Yes,
that's a word used in the Perl documentation! It shows three hits and
asks the user to enter a number between 1 and 3 to open the selected
documentation page in a pager program (typically C<less>). In there,
an in-text search for the expression can be started by using the C</>
(slash) command.

If two or more keywords are given, the search will yield pages that
contain all of them. When searching for phrases, please include quotes
(make sure to quote the quotes so the shell doesn't eat them):

   $ perldig '"floating point"'

The underlying I<swish-e> search engine also understands expressions
connected via AND and OR:

  $ perldig "'floating point' AND approximate AND 'real number'"

To keep the index up to date, it is probably a good idea to run a
cronjob every morning:

    00 4 * * * /usr/bin/perldig -u >/dev/null 2>&1

If you can read German, please check out this article in the "Linux-
Magazin", where this script was originally published:

    http://www.linux-magazin.de/Artikel/ausgabe/2003/10/perl/perl.html

=head1 EXAMPLES

    # Update/create the index 
  $ perldig -u
  
  $ perldig frobnicate

  1) pod/perlguts.pod    2) pod/perlxstut.pod   3) pod/perlnewmod.pod  

  Enter number of choice: 1
  [ ... perlguts man page shows ... ]

=head1 FILES

C<perldig> puts the I<swish-e> index files into the folder C<.perldig>
in the user's home directory.

=head1 LEGALESE

Copyright 2003-2005 by Mike Schilli, all rights reserved.
This program is free software, you can redistribute it and/or
modify it under the same terms as Perl itself.

=head1 AUTHOR

2003, Mike Schilli <m@perlmeister.com>