guestbook-ng/lib/GuestbookNg/Model/Message.pm

#!/usr/bin/env perl

package GuestbookNg::Model::Message;

use Mojo::Base -base, -signatures;

has 'pg';

sub new($class, $pg, $pg_object) {
    bless {
        $pg       => $pg_object,
        max_posts => 5
    }
}

sub get_posts($self) {
    $self->pg->db->query(<<~'END_SQL')->arrays()
        SELECT to_char(message_date, 'Dy Mon DD HH:MI:SS AM TZ YYYY'),
               visitor_name,
               message
          FROM messages
         ORDER BY message_date DESC;
       END_SQL
}

sub create_post($self, $name, $message) {
    $self->pg->db->query(<<~'END_SQL', $name, $message)
        INSERT INTO messages (message_date, visitor_name, message)
        VALUES (NOW(), ?, ?);
       END_SQL
}

sub view_posts($self, $this_page, $last_page = undef, @posts) {
    $last_page //= get_last_page(@posts);

    my $last_post  = $this_page * $self->{'max_posts'} - 1;
    my $first_post = $last_post - $self->{'max_posts'} + 1;

    grep defined, @posts[$first_post..$last_post];
}

sub max_posts($self, $value = undef) {
    $self->{'max_posts'} = $value // $self->{'max_posts'}
}

sub get_last_page($self, @posts) {
    # Add a page if we have "remainder" posts
    if (scalar(@posts) % $self->{'max_posts'}) {
        sprintf('%d', scalar(@posts) / $self->{'max_posts'}) + 1
    }
    else {
        sprintf('%d', scalar(@posts) / $self->{'max_posts'})
    }
}

1;