# Based on Mojolicious-Plugin-TagHelpers-Pagination and slightly modified for bootstrap

# Under Artistic License 2.0

package Mojolicious::Plugin::TagHelpers::BootstrapPagination;

use Mojo::Base 'Mojolicious::Plugin';

use Mojo::ByteStream 'b';

use Scalar::Util 'blessed';

use POSIX 'ceil';

our $VERSION = 0.01;

our @value_list =

  qw/prev

     next

     current_start

     current_end

     page_start

     page_end

     separator

     ellipsis

     placeholder/;

# Register plugin

sub register {

  my ($plugin, $mojo, $param) = @_;

  $param ||= {};

  # Load parameter from Config file

  if (my $config_param = $mojo->config('TagHelpers-Pagination')) {

    $param = { %$config_param, %$param };

  };

  foreach (@value_list) {

    $plugin->{$_} = $param->{$_} if defined $param->{$_};

  };

  # Set 'current_start' and 'current_end' symbols,

  # if 'current' template is available.

  # Same for 'page'.

  foreach (qw/page current/) {

    if (defined $param->{$_}) {

      @{$plugin}{$_ . '_start', $_ . '_end'} = split("{$_}", $param->{$_});

      $plugin->{$_ . '_end'} ||= '';

    };

  };

  # Default current start and current end symbols

  for ($plugin) {

    $_->{current_start} //= '';

    $_->{current_end}   //= '';

    $_->{page_start}    //= '';

    $_->{page_end}      //= '';

    $_->{prev}          //= '<';

    $_->{next}          //= '>';

    $_->{separator}     //= '';

    $_->{ellipsis}      //= '<li><span>...</span></li>';

    $_->{placeholder}   //= 'page';

  };

  # Establish pagination helper

  $mojo->helper(

    pagination => sub {

      shift; # Controller

      return b( $plugin->pagination( @_ ) );

    });

};

# Pagination helper

sub pagination {

  my $self = shift;

  # $_[0] = current page

  # $_[1] = page count

  # $_[2] = template or Mojo::URL

  return '' unless $_[0] || $_[1];

  # No valid count given

  local $_[1] = !$_[1] ? 1 : ceil($_[1]);

  # New parameter hash

  my %values =

    map { $_ => $self->{$_} } @value_list;

  # Overwrite plugin defaults

  if ($_[3] && ref $_[3] eq 'HASH') {

    my $overwrite = $_[3];

    foreach (@value_list) {

      $values{$_}  = $overwrite->{$_} if defined $overwrite->{$_};

    };

    foreach (qw/page current/) {

      if (defined $overwrite->{$_}) {

	@values{$_ . '_start', $_ . '_end'} = split("{$_}", $overwrite->{$_});

	$values{$_ . '_end'} ||= '';

      };

    };

  };

  # Establish string variables

  my ($p, $n, $cs, $ce, $ps, $pe, $s, $el, $ph) = @values{@value_list};

  # prev next current_start current_end

  # page_start page_end separator ellipsis placeholder

  # Template

  my $t = $_[2];

  if (blessed $t && blessed $t eq 'Mojo::URL') {

    $t = $t->to_string;

    $t =~ s/\%7[bB]$ph\%7[dD]/{$ph}/g;

  };

  my $sub = sublink_gen($t,$ps,$pe,$ph);

  # Pagination string

  my $e;

  my $counter = 1;

  if ($_[1] >= 7){

    # < [1] #2 #3

    if ($_[0] == 1){

      $e .= $sub->(undef, [$p, 'prev']) . $s .

	    $sub->(undef, [$cs . 1  . $ce, 'self']) . $s .

	    $sub->('2') . $s .

	    $sub->('3') . $s;

    }

    # < #1 #2 #3

    elsif (!$_[0]) {

      $e .= $sub->(undef, [$p, 'prev']) . $s;

      $e .= $sub->($_) . $s foreach (1 .. 3);

    }

    # #< #1

    else {

      $e .= $sub->(($_[0] - 1), [$p, 'prev']) . $s .

            $sub->('1') . $s;

    };

    # [2] #3

    if ($_[0] == 2){

      $e .= $sub->(undef, [$cs . 2 . $ce, 'self']) . $s .

	    $sub->('3') . $s;

    }

    # ...

    elsif ($_[0] > 3){

      $e .= $el . $s;

    };

    # #x-1 [x] #x+1

    if (($_[0] >= 3) && ($_[0] <= ($_[1] - 2))){

      $e .= $sub->($_[0] - 1) . $s .

	    $sub->(undef, [$cs .$_[0] . $ce, 'self']) . $s .

	    $sub->($_[0] + 1) . $s;

    };

    # ...

    if ($_[0] < ($_[1] - 2)){

      $e .= $el . $s;

    };

    # number is prefinal

    if ($_[0] == ($_[1] - 1)){

      $e .= $sub->($_[1] - 2) . $s .

	    $sub->(undef, [$cs . $_[0] . $ce, 'self']) . $s;

    };

    # Number is final

    if ($_[0] == $_[1]){

      $e .= $sub->($_[1] - 1) . $s .

            $sub->(undef, [$cs . $_[1] . $ce, 'self']) . $s .

	    $sub->(undef, [$n, 'next']);

    }

    # Number is anywhere in between

    else {

      $e .= $sub->($_[1]) . $s .

            $sub->(($_[0] + 1), [$n,'next']);

    };

  }

  # Counter < 7

  else {

    # Previous

    if ($_[0] > 1){

      $e .= $sub->(($_[0] - 1), [$p, 'prev']) . $s;

    } else {

      $e .= $sub->(undef, [$p, 'prev']) . $s;

    };

    # All numbers in between

    while ($counter <= $_[1]){

      if ($_[0] != $counter) {

        $e .= $sub->($counter) . $s;

      }

      # Current

      else {

        $e .= $sub->(undef, [$cs . $counter . $ce, 'self']) . $s;

      };

      $counter++;

    };

    # Next

    if ($_[0] != $_[1]){

      $e .= $sub->(($_[0] + 1), [$n, 'next']);

    }

    else {

      $e .= $sub->(undef, [$n, 'next']);

    };

  };

  # Pagination string

  $e;

};

# Sublink function generator

sub sublink_gen {

  my ($url, $ps, $pe, $ph) = @_;

  my $s = 'sub {';

  # $_[0] = number

  # $_[1] = number_shown

  # Url is template

  if ($url) {

    $s .= 'my $url=' . b($url)->quote . ';';

    $s .= 'if($_[0]){$url=~s/\{' . $ph . '\}/$_[0]/g}else{$url=undef};';

  }

  # No template given

  else {

    $s .= 'my $url = $_[0];';

  };

  $s .= 'my$n=$_[1]||' . b($ps)->quote . '.$_[0].' . b($pe)->quote . ';';

  $s .= q{my $liclass='';};

  $s .= q{if(ref $n && $n->[1] eq "self"){$liclass = "active"};};

  $s .= q{my $rel='';};

  $s .= q{if(ref $n){$rel=' rel="'.$n->[1].'"';$n=$n->[0]};};

  $s .= q!if($url){$url=~s/&/&/g;!;

  $s .= q{$url=~s/</&lt;/g;};

  $s .= q{$url=~s/>/>/g;};

  $s .= q{$url=~s/"/"/g;};

  $s .= q!$url=~s/'/'/g;};!;

  # Create sublink

  $s .= q{return '<li'.($liclass?' class="'.$liclass.'"':'').'><a'.($url?' href="'.$url.'"':'').$rel.'>' . $n . '</a></li>';};

  $s .= '}';

  my $x = eval($s);

  warn $@ if $@;

  $x;

};

1;

__END__

=pod

=head1 NAME

Mojolicious::Plugin::TagHelpers::Pagination - Pagination Helper for Mojolicious

=head1 SYNOPSIS

  # Mojolicious

  $app->plugin('TagHelpers::Pagination' => {

    separator => ' ',

    current => '<strong>{current}</strong>'

  });

  # Mojolicious::Lite

  plugin 'TagHelpers::Pagination' => {

    separator => ' ',

    current   =>  '<strong>{current}</strong>'

  };

  # In Templates

  %= pagination(2, 4, '?page={page}' => { separator => "\n" })

  # <a href="?page=1" rel="prev">&lt;</a>

  # <a href="?page=1">1</a>

  # <a rel="self"><strong>2</strong></a>

  # <a href="?page=3">3</a>

  # <a href="?page=4">4</a>

  # <a href="?page=3" rel="next">&gt;</a>

=head1 DESCRIPTION

L<Mojolicious::Plugin::TagHelpers::Pagination> helps you to create

pagination elements in your templates, like this:

L<E<lt>|/#> L<1|/#> ... L<5|/#> B<[6]> L<7|/#> ... L<18|/#> L<E<gt>|/#>

=head1 METHODS

L<Mojolicious::Plugin::TagHelpers::Pagination> inherits all methods from

L<Mojolicious::Plugin> and implements the following new one.

=head2 register

  # Mojolicious

  $app->plugin('TagHelpers::Pagination' => {

    separator => ' ',

    current => '<strong>{current}</strong>'

  });

  # Or in your config file

  {

    'TagHelpers-Pagination' => {

      separator => ' ',

      current => '<strong>{current}</strong>'

    }

  }

Called when registering the plugin.

All L<parameters|/PARAMETERS> can be set either on registration or

as part of the configuration file with the key C<TagHelpers-Pagination>.

=head1 HELPERS

=head2 pagination

  # In Templates:

  %= pagination(4, 6 => '/page-{page}.html');

  % my $url = Mojo::URL->new->query({ page => '{page}'});

  %= pagination(4, 6 => $url);

  %= pagination(4, 6 => '/page/{page}.html', { current => '<b>{current}</b>' });

Generates a pagination string.

Expects at least two numeric values: the current page number and

the total count of pages.

Additionally it accepts a link pattern and a hash reference

with parameters overwriting the default plugin parameters for

pagination.

The link pattern can be a string using a placeholder in curly brackets

(defaults to C<page>) for the page number it should link to.

It's also possible to give a

L<Mojo::URL> object containing the placeholder.

The placeholder can be used multiple times.

=head1 PARAMETERS

For the layout of the pagination string, the plugin accepts the

following parameters, that are able to overwrite the default

layout elements. These parameters can again be overwritten in

the pagination helper.

=over 2

=item current

Pattern for current page number. The C<{current}> is a

placeholder for the current number.

Defaults to C<[{current}]>.

Instead of a pattern, both sides of the current number

can be defined with C<current_start> and C<current_end>.

=item ellipsis

Placeholder symbol for hidden pages. Defaults to C<...>.

=item next

Symbol for next pages. Defaults to C<&gt;>.

=item page

Pattern for page number. The C<{page}> is a

placeholder for the page number.

Defaults to C<{page}>.

Instead of a pattern, both sides of the page number

can be defined with C<page_start> and C<page_end>.

=item placeholder

String representing the placeholder for the page number in the URL

pattern. Defaults to C<page>.

=item prev

Symbol for previous pages. Defaults to C<&lt;>.

=item separator

Symbol for the separation of pagination elements.

Defaults to C<&nbsp;>.

=back

=head1 DEPENDENCIES

L<Mojolicious>.

=head1 AVAILABILITY

  https://github.com/Akron/Mojolicious-Plugin-TagHelpers-Pagination

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2012-2014, L<Nils Diewald|http://nils-diewald.de/>.

This program is free software, you can redistribute it

and/or modify it under the terms of the Artistic License version 2.0.

=cut