#!/usr/bin/perl -w

# Copyright 2013 Kevin Ryde

# This file is part of Perl-Critic-Pulp.
#
# Perl-Critic-Pulp 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 3, or (at your option) any
# later version.
#
# Perl-Critic-Pulp is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with Perl-Critic-Pulp.  If not, see <http://www.gnu.org/licenses/>.


# p-class.pl
# Acme::Tie::Eleet     duplicate BUGS

use 5.005;
use strict;
use warnings;
use Tie::IxHash;

use lib::abs '.';
use MyLocatePerl;
use MyStuff;

# uncomment this to run the ### lines
# use Smart::Comments;

my $verbose = 0;
my $scope = 'consecutive';

my $l = MyLocatePerl->new (exclude_t => 1,
                           include_pod => 1,
                           under_directory => '/usr/share/perl5',
                          );
while (my ($filename, $str) = $l->next) {
  if ($verbose) { print "look at $filename\n"; }

  my $seen = {};
  my @backtrack;
  my $prev_level = 0;
  while ($str =~ /^=head(\d+)\s+(.*?)\s*$/mg) {
    my $level = $1;
    my $name = $2;
    my $pos = $-[0];

    if ($scope eq 'all') {

    } elsif ($scope eq 'consecutive') {

    } elsif ($scope eq 'nested') {
      if ($level < $prev_level) {
        $seen = $backtrack[$level];
        ### ascend, backtrack to level: $level
      } elsif ($level > $prev_level) {
        ### descend, copy ...
        $seen = { %$seen };
      }

    } elsif ($scope eq 'level') {
      if ($level < $prev_level) {
        $seen = $backtrack[$level];
        ### ascend, backtrack to level: $level
      } elsif ($level > $prev_level) {
        ### descend, copy ...
        $seen = { %$seen };
      }

    } else {
      die "Unknown scope $scope";
    }

    ### look in: $seen
    if (my $prev_pos = $seen->{$name}) {
      {
        my ($line, $col) = MyStuff::pos_to_line_and_column ($str, $prev_pos);
        my $s = MyStuff::line_at_pos($str, $pos);
        print "$filename:$line:$col: duplicate heading here\n  $s";
      }
      {
        my ($line, $col) = MyStuff::pos_to_line_and_column ($str, $pos);
        my $s = MyStuff::line_at_pos($str, $pos);
        print "$filename:$line:$col: and here\n  $s";
        print "\n";
      }
    }

    if ($scope eq 'consecutive') { %$seen = (); }
    $seen->{$name} = $pos;
    $backtrack[$level] = $seen;
    $prev_level = $level;
  }
  # exit 0;

  # my %seen;
  # tie %seen, 'Tie::IxHash';
  # while (my ($name, $aref) = each %seen) {
  #   if (@$aref > 1) {
  #     foreach my $pos (@$aref) {
  #       my ($line, $col) = MyStuff::pos_to_line_and_column ($str, $pos);
  #       my $s = MyStuff::line_at_pos($str, $pos);
  #       print "$filename:$line:$col: duplicate heading\n  $s";
  #     }
  #   }
  # }
}

exit 0;

=head1 FOO

=head2 Dup

=head2 Dup

=head1 BAR

=head2 Dup