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/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);
+  }
+}
+
+?>