#!/usr/bin/env perl

=pod

=head1 NAME

wrt-display - print static HTML from wrt entries

=head1 USAGE

    wrt display new       # newest entries
    wrt display all       # table of contents for all dated entries
    wrt display 2016/4/1  # a specific date
    wrt display 2016/4    # all entries for a specific month
    wrt display 2016/4    # summary of entries for a year
    wrt display fulltext  # complete text of archive
    wrt display feed      # Atom feed of most recent month's entries

    # Take list of entries to display from standard input:
    echo 2016/4/1 | wrt display --stdin

    # Specify a different config file:
    wrt display --config ./wrt.json ...

    # Display help:
    wrt display --help

=head1 DESCRIPTION

C<wrt-display> displays HTML for the given entry or entries in the current wrt
repository to F<stdout>.  Entries may be specified by date or name.

=head2 Special Entries

B<new> will return entries for the most recent month.

B<feed> will return an Atom feed for the most recent month.

B<all> will return a table-of-contents for all date-based entries.

B<fulltext> will return the full content of all date-based entries in the
archive.

Months in the form of B<yyyy/mm> will return all entries for that month.

Years in the form of B<yyyy> will return a summary of entries for the year.

Detailed documentation can be found in the L<App::WRT> man page or at
L<https://code.p1k3.com/gitea/brennen/wrt>.

=head1 LICENSE

    wrt is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

=head1 AUTHOR

Brennen Bearnes <code@p1k3.com>

=cut

use 5.10.0;

use strict;
use warnings;
no  warnings 'uninitialized';

# use Data::Dumper;
use App::WRT;

use Carp;
use Getopt::Long;
use Pod::Usage;

# Handle options, including help generated from the POD above.  See:
# - http://perldoc.perl.org/Getopt/Long.html#User-defined-subroutines-to-handle-options
# - https://metacpan.org/pod/Pod::Usage
# - http://michael.thegrebs.com/2014/06/08/Pod-Usage/
my $from_stdin  = 0;
my $config_file = 'wrt.json';
GetOptions(
  stdin      => \$from_stdin,
  'config=s' => \$config_file,
  help       => sub { pod2usage(0) },
) or pod2usage(2);

unless (-e $config_file) {
  croak "No wrt config file found.  Tried: $config_file";
}

my $w = App::WRT::new_from_file($config_file);

# With --stdin, take names of entries to display from standard input, one line
# per name.  Otherwise, take names from arguments.
my @to_display = ();
if ($from_stdin) {
  while (my $entry = <>) {
    chomp($entry);
    push @to_display, $entry;
  }
} else {
  (@to_display) = @ARGV;
}

# TODO: Better error reporting strategy, print this on stderr:
foreach my $entry (map { $w->expand_alias($_) } @to_display) {
  unless ($w->{entries}->is_extant($entry) || $entry eq $w->{feed_alias}) {
    say("No such entry: $entry");
    exit(1);
  }
}
print $w->display(@to_display);
exit(0);