From e702fd91395e7664a313dc91d331f09bf70aa361 Mon Sep 17 00:00:00 2001
From: swaggboi <swaggboi@slackware.uk>
Date: Sun, 14 Aug 2022 18:30:22 -0400
Subject: [PATCH] Implement paging for viewing threads (and fixed a broken
 test)

---
 PostText.pl                              | 31 +++++++++++++---
 cpanfile                                 |  1 +
 lib/PostText/Model/Thread.pm             | 46 ++++++++++++++++++++++--
 t/post.t                                 |  2 +-
 templates/{view.html.ep => page.html.ep} |  5 +++
 5 files changed, 77 insertions(+), 8 deletions(-)
 rename templates/{view.html.ep => page.html.ep} (74%)

diff --git a/PostText.pl b/PostText.pl
index 03a3131..d9887bc 100755
--- a/PostText.pl
+++ b/PostText.pl
@@ -5,7 +5,7 @@
 
 use Mojolicious::Lite -signatures;
 use Mojo::Pg;
-#use Data::Dumper; # For your debugging pleasure
+use Data::Dumper; # For your debugging pleasure
 
 # Load the local modules too
 use lib 'lib';
@@ -13,6 +13,7 @@ use PostText::Model::Thread;
 
 # Load Mojo plugins
 plugin 'Config';
+plugin 'TagHelpers::Pagination';
 
 # Helpers
 helper pg => sub {
@@ -34,12 +35,28 @@ under sub ($c) {
 get '/', sub ($c) { $c->redirect_to('view') };
 
 # View
-get '/view', sub ($c) {
-    my $threads = $c->thread->get_threads();
+group {
+    under 'view';
 
-    $c->stash(threads => $threads);
+    get '/:page', [page => qr/[0-9]+/], {page => 1}, sub ($c) {
+        my $base_path = '/view';
+        my $this_page = $c->param('page');
+        my $last_page = $c->thread->get_last_page();
+        my $threads   = $c->thread->get_threads_by_page($this_page);
 
-    $c->render();
+        $c->stash(
+            threads   => $threads,
+            this_page => $this_page,
+            last_page => $last_page,
+            base_path => $base_path
+            );
+
+        unless (my $thread = @$threads[0]) {
+            $c->stash(status => 404)
+        }
+
+        $c->render();
+    };
 };
 
 # Post
@@ -71,5 +88,9 @@ app->secrets(app->config->{'secrets'}) || die $@;
 
 app->pg->migrations->from_dir('migrations')->migrate(3);
 
+if (my $threads_per_page = app->config->{'threads_per_page'}) {
+    app->thread->threads_per_page($threads_per_page)
+}
+
 # Send it
 app->start();
diff --git a/cpanfile b/cpanfile
index 24a65db..3aa5e26 100644
--- a/cpanfile
+++ b/cpanfile
@@ -1,2 +1,3 @@
 requires 'Mojolicious';
 requires 'Mojo::Pg';
+requires 'Mojolicious::Plugin::TagHelpers::Pagination';
diff --git a/lib/PostText/Model/Thread.pm b/lib/PostText/Model/Thread.pm
index 749cb0b..de475c2 100644
--- a/lib/PostText/Model/Thread.pm
+++ b/lib/PostText/Model/Thread.pm
@@ -7,7 +7,10 @@ use Mojo::Base -base, -signatures;
 has 'pg';
 
 sub new($class, $pg, $pg_reference) {
-    bless {$pg => $pg_reference}, $class
+    bless {
+        $pg              => $pg_reference,
+        threads_per_page => 5
+    }, $class
 }
 
 sub create_thread($self, $author, $title, $body, $hidden = 0, $flagged = 0) {
@@ -25,7 +28,7 @@ sub create_thread($self, $author, $title, $body, $hidden = 0, $flagged = 0) {
     END_SQL
 }
 
-sub get_threads($self) {
+sub get_all_threads($self) {
     $self->pg->db->query(<<~'END_SQL')->hashes()
         SELECT thread_id                                             AS id,
                TO_CHAR(thread_date, 'Dy Mon DD HH:MI:SS AM TZ YYYY') AS date,
@@ -38,4 +41,43 @@ sub get_threads($self) {
        END_SQL
 }
 
+sub get_threads_by_page($self, $this_page = 1) {
+    my $row_count = $self->{'threads_per_page'};
+    my $offset    = ($this_page - 1) * $row_count;
+
+    $self->pg->db->query(<<~'END_SQL', $row_count, $offset)->hashes();
+        SELECT thread_id                                             AS id,
+               TO_CHAR(thread_date, 'Dy Mon DD HH:MI:SS AM TZ YYYY') AS date,
+               thread_author                                         AS author,
+               thread_title                                          AS title,
+               thread_body                                           AS body
+          FROM threads
+         WHERE NOT hidden_status
+         ORDER BY thread_date DESC
+         LIMIT ? OFFSET ?;
+       END_SQL
+}
+
+sub threads_per_page($self, $value = undef) {
+    $self->{'threads_per_page'} = $value // $self->{'threads_per_page'}
+}
+
+sub get_last_page($self) {
+    my $thread_count = $self->get_thread_count();
+    my $last_page    = int($thread_count / $self->{'threads_per_page'});
+
+    # Add a page for 'remainder' posts
+    return ++$last_page if $thread_count % $self->{'threads_per_page'};
+
+    return $last_page;
+}
+
+sub get_thread_count($self) {
+    $self->pg->db->query(<<~'END_SQL')->text()
+        SELECT COUNT(*)
+          FROM threads
+         WHERE NOT hidden_status;
+       END_SQL
+}
+
 1;
diff --git a/t/post.t b/t/post.t
index aee4a27..33dd6cb 100644
--- a/t/post.t
+++ b/t/post.t
@@ -11,7 +11,7 @@ my $t      = Test::Mojo->new($script);
 my %valid_params = (
     name  => 'Anonymous',
     title => 'hi',
-    body  => 'ayy... lmao'
+    post  => 'ayy... lmao'
     );
 
 $t->ua->max_redirects(1);
diff --git a/templates/view.html.ep b/templates/page.html.ep
similarity index 74%
rename from templates/view.html.ep
rename to templates/page.html.ep
index 2a7c3db..49d68b3 100644
--- a/templates/view.html.ep
+++ b/templates/page.html.ep
@@ -11,3 +11,8 @@
     </article>
   <% } =%>
 </div>
+<% if ($last_page && $last_page != 1) { =%>
+<nav>
+  <%= pagination $this_page, $last_page, ($base_path . '/{page}') %>
+</nav>
+<% } =%>