#!/usr/bin/env perl

use strict;
use warnings;

use Perlanet::Simple;
use Getopt::Std;
use File::Basename;

our $VERSION = $Perlanet::VERSION;

my %opts;
getopts('hv', \%opts);

version() if $opts{v} || $opts{h};
help()    if $opts{h};
exit      if $opts{v} || $opts{h};

my $cfg = shift || './perlanetrc';
my $p = Perlanet::Simple->new_with_config(configfile => $cfg);


sub version {
  my ($me) = fileparse $0;

  print "\n$me, version $VERSION\n\n";

sub help {
  my ($me) = fileparse $0;

  print <<EOTEXT;
Usage: $me [-h] [-v] [config_file]

  -h Display this help message
  -v Display version information

     Name of configuration file (defaults to perlanetrc)


=head1 NAME

perlanet - command line interface to Perlanet.pm


  $ perlanet


  $ perlanet config_file


C<perlanet> is a command line program for aggregating web feeds (both Atom
and RSS) and publishing a new web page and a new web feed containing the
results of that aggregation.


C<perlanet> takes one optional command line argument, which is the name of
a configuration file to use. If no filename is given then the program looks
for a file called C<perlanetrc> in the current directory.


C<perlanet> requires a configuration file which contains details of which
feeds to aggregate and what to do with the results of the aggregation. By
default, C<perlanet> looks for a file called C<perlanetrc> in the current
directory, but this name can be overridden by passing the name of a different
file when calling the program.

The configuration file is in YAML format. YAML is a simple text-based file
format. See L<http://yaml.org/> for further details.

=head2 Configuration Options

The configuration file can contain the following options.

=over 4

=item title

The title of the resulting page and web feed. This option is mandatory.

=item description

The description of the resulting page and web feed. This option is mandatory.

=item url

A URL which will be associated with the resulting page and web feed. This will
usually be the address where the web page will be published. This option is

=item author

The name and email address of the author of the aggregated content. This
item has two sub-items - one each for the name and email address. This option
is mandatory.

=item agent

This optional entry defines the agent string that perlanet will use when
requesting data from web sites. It's the name of the program that site owners
will see in their web site access logs. Although it is optional, it is strongly
recommended that you give a value for this configuration option and that the
value you use includes contact details so that web site owners can get in
touch with you if they have any concerns about your use of their site.

=item entries

The maximum number of entries to include in the aggregated content. This option
is mandatory.

=item entries_per_feed

The C<entries> value above defines the total number of entries in the
aggregated output feed. The <entries_per_feed> value defines the number of
entries to take from each of your source feeds. For example, if this is
set to 1 then there will only be one entry from each feed in your output.
If this value is 0 (or missing) then all values from all source feeds are

=item entry_sort_order

Entries have two dates, issued (which is the date that the item was first
published) and modified (which is the date that the item was last updated).
This configuration option controls which of these two dates are used to sort
the entries in a feed. It can be one of the two values C<issued> or
C<modified>. If this option is omitted, then C<modified> is used.

=item cutoff_duration

Sometimes you might want your generated feed to only contain entries from,
say, the last month. You can do that with the C<cutoff_duration> configuration
option. This takes the form of sub-parameters which are in the same format
as you would use when calling the constructor for
L<DateTime::Duration> (which isn't surprising as that's what happens to
them). For example the to exclude entries that are more than a month old,
you would use:

      months: 1

=item opml

The system can optionally create an OPML file containing details of the
feeds which are being aggregated. This optional option controls whether or not
this file is created. If it exists, it should be the name of the OPML file
to be created. If an OPML file is being created, then the C<feeds> options
(described below) will all require a C<web> sub-option.

=item page

This mandatory option contains the details of the web page to be created.
There are two sub-options - C<file> gives the name of the file to be created
and C<template> gives the name of a Template Toolkit template which will be
processed in order to create this file. See the section L<Output Template>
for more details on this template, and the web site L<http://tt2.org/> for
more information about the Template Toolkit.

=item feed

This mandatory option contains the details of the web feed to be created.
There are two sub-options - C<file> gives the name of the file to be created
and C<format> gives the format of the output (currently 'Atom' or 'RSS').

=item cache_dir

This if you give a directory name in this option then perlanet will use the
cache facility of URI::Fetch. This means that web feeds will only be downloaded
when they change.

=item feeds

This mandatory option gives details of the web feeds to be aggregated. Each
item on the list has one mandatory sub-option and two optional sub-options.
The mandatory sub-option is C<url> which gives the URL of the feed. The
optional sub-option C<title> gives a title to the feed which can be used
to identify the entries that originate from this feed. The optional C<web>
sub-option gives a web site URL associated with the feed (often the address
of the web site that the feed comes from). This can be used to create a list
of the aggregated sites. The C<web> sub-option becomes mandatory if you are
creating an OPML file. You can also add a C<max_entries> option which will
override the global C<entries_per_feed> setting. If this setting exists
and is set to zero, then the output feed will contain all of the entries
from this input feed.


=head2 Example Configuration File

  title: planet test
  description: A Test Planet
  url: http://planet.example.com/
    name: Dave Cross
    email: dave@dave.org.uk
  entries: 20
  opml: opml.xml
    file: index.html
    template: index.tt
    file: atom.xml
    format: Atom
  cache_dir: /tmp/feeds
    - url: http://blog.dave.org.uk/atom.xml
      title: Dave's Blog
      web: http://blog.dave.org.uk/
    - url: http://use.perl.org/~davorg/journal/rss
      title: Dave's use.perl Journal
      web: http://use.perl.org/~davorg/journal/
    - url: http://www.oreillynet.com/pub/feed/31?au=2607
      title: Dave on O'Reillynet
      web: http://www.oreillynet.com/pub/au/2607

=head2 Output Template

The web page is created from a Template Toolkit template. This template is
passed two variables.

=over 4

=item feed

This is the XML::Feed object which has been used to create the aggregated
feed. See the L<XML::Feed> documentation for details of the data that is
held in this object.

=item cfg

This is the contents of the configuration file, converted to a (nested)
Perl hash.


=head2 Example Output Template

This is a simple template which uses the C<feed> variable to display details
of the aggregated feeds.

  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
  <html xmlns="http://www.w3.org/1999/xhtml">
      <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
      <title>[% feed.title %]</title>
      <h1>[% feed.title | html %]</h1>
      <p>[% feed.description | html %]</p>
  [% FOREACH entry IN feed.entries %]
      <h2><a href="[% entry.link | url | html %]">[% entry.title | html %]</h2></a>
      [% entry.content.body %]
  [% IF entry.author OR entry.issued %]
      <p>Published[% IF entry.author %] by [% entry.author | html; END %]
      [% IF entry.issued %] on [% entry.issued | html; END %]</p>
  [% END %]
  [% END %]
      <hr />
      <address>[% feed.author | html %] / [% feed.modified | html %]</address>

In the future, the Perlanet wiki at L<http://wiki.github.com/davorg/perlanet>
will contain a cookbook of useful ideas to include in the output template.

=head1 SUPPORT

To report bugs in Perlanet, please use the CPAN request tracker. You can
either use the web page at
L<http://rt.cpan.org/Public/Bug/Report.html?Queue=Perlanet> or send an email
to bug-Perlanet@rt.cpan.org.

=head1 SEE ALSO

=over 4

=item *


=item *



=head1 AUTHOR

Dave Cross, <dave@perlhacks.com>


Copyright (C) 2008 by Magnum Solutions Ltd.

This progam library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself, either Perl version 5.10.0 or,
at your option, any later version of Perl 5 you may have available.