Refactor sidebar configuration

Instead of editing an if statement (which could get ugly quickly), just
edit configuration arrays of conditional tags and page template checks.

lib/config.php

@@ -9,18 +9,37 @@ add_theme_support('rewrite-urls');          // Enable URL rewrites
 add_theme_support('h5bp-htaccess');         // Enable HTML5 Boilerplate's .htaccess
 add_theme_support('bootstrap-top-navbar');  // Enable Bootstrap's fixed navbar
 
-// Define which pages shouldn't have the sidebar
-function roots_sidebar() {
-  if (is_404() || is_page_template('page-custom.php')) {
-    return false;
-  } else {
-    return true;
-  }
+
+/**
+ * Define which pages shouldn't have the sidebar
+ *
+ * See lib/sidebar.php for more details
+ */
+function roots_display_sidebar() {
+  $exclude = new Roots_Sidebar(
+    /**
+     * Conditionals tag checks (http://codex.wordpress.org/Conditional_Tags)
+     * Any of these conditional tags that return true won't show the sidebar
+     */
+    array(
+      '404',
+      'front_page'
+    ),
+    /**
+     * Page template checks (via is_page_template())
+     * Any of these page templates that return true won't show the sidebar
+     */
+    array(
+      'page-custom'
+    )
+  );
+
+  return $exclude->display;
 }
 
 // #main CSS classes
 function roots_main_class() {
-  if (roots_sidebar()) {
+  if (roots_display_sidebar()) {
     echo 'span8';
   } else {
     echo 'span12';

lib/sidebar.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * Determines whether or not to display the sidebar based on an array of conditional tags or page templates.
+ *
+ * If any of the is_* conditional tags or is_page_template(template_file) checks return true, the sidebar will NOT be displayed.
+ *
+ * @param array list of conditional tags (http://codex.wordpress.org/Conditional_Tags) without the 'is_' prefix
+ * @param array list of templates without the '.php' extension. These will be checked via is_page_template()
+ *
+ * @return boolean True will display the sidebar, False will not
+ *
+ */
+class Roots_Sidebar {
+  const EXTENSION = '.php';
+  private $conditionals;
+  private $templates;
+  public $display = true;
+
+  function __construct($conditionals = array(), $templates = array()) {
+    $this->conditionals = $conditionals;
+    $this->templates    = $templates;
+
+    foreach($this->conditionals as $conditional_tag) {
+      if ($this->check_conditional_tag($conditional_tag)) {
+        $this->display = false;
+      }
+    }
+
+    foreach($this->templates as $page_template) {
+      if ($this->check_page_template($page_template)) {
+        $this->display = false;
+      }
+    }
+  }
+
+  private function check_conditional_tag($conditional_tag) {
+    $function = "is_$conditional_tag";
+    return $function();
+  }
+
+  private function check_page_template($page_template) {
+    return is_page_template($page_template . self::EXTENSION);
+  }
+}
+
+?>