diff --git a/blazer-six-gist-oembed.php b/blazer-six-gist-oembed.php
index 26d868e..cd67ad4 100644
--- a/blazer-six-gist-oembed.php
+++ b/blazer-six-gist-oembed.php
@@ -9,581 +9,87 @@
  * License: GPLv2 or later
  * License URI: http://www.gnu.org/licenses/gpl-2.0.html
  *
- * @package Blazer_Six_Gist_oEmbed
+ * @package BlazerSix\GistoEmbed
  * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <gary@garyjones.co.uk>
  * @copyright Copyright (c) 2012, Blazer Six, Inc.
  * @license GPL-2.0+
+ */
+
+// Instantiate main plugin class
+if ( ! class_exists( 'Blazer_Six_Gist_oEmbed' ) ) {
+	require( plugin_dir_path( __FILE__ ) . 'class-blazer-six-gist-oembed.php' );
+}
+$gist_oembed = new Blazer_Six_Gist_oEmbed;
+
+// Instantiate logging class
+if ( ! class_exists( 'Blazer_Six_Gist_oEmbed_Log' ) ) {
+	require( plugin_dir_path( __FILE__ ) . 'class-blazer-six-gist-oembed-log.php' );
+}
+$gist_oembed_logger = new Blazer_Six_Gist_oEmbed_Log;
+
+add_action( 'init', 'blazer_six_gist_oembed_localization' );
+/**
+ * Support localization for plugin.
+ *
+ * @see http://www.geertdedeckere.be/article/loading-wordpress-language-files-the-right-way
  *
- * @todo Feed support: link directly to post, directly to Gist, or wrap in iframe?
- * @todo Cache the stylesheet locally.
+ * @since 1.1.0
  */
+function blazer_six_gist_oembed_localization() {
+	$domain = 'blazersix-gist-oembed';
+	// The "plugin_locale" filter is also used in load_plugin_textdomain()
+	$locale = apply_filters( 'plugin_locale', get_locale(), $domain );
+	load_textdomain( $domain, WP_LANG_DIR . '/my-plugin/' . $domain . '-' . $locale . '.mo' );
+	load_plugin_textdomain( $domain, false, dirname( plugin_basename( __FILE__ ) ) . '/languages/' );
+}
 
+add_action( 'init', 'blazer_six_gist_oembed_init' );
 /**
- * Load the plugin when plugins are loaded.
+ * Set plugin logger class and initialise plugin.
+ *
+ * If you want a different logger class, then unhook this function, and hook
+ * in your own which does what you need.
+ *
+ * @since 1.1.0
  */
-add_action( 'plugins_loaded', array( 'Blazer_Six_Gist_oEmbed', 'instance' ) );
+function blazer_six_gist_oembed_init() {
+	global $gist_oembed, $gist_oembed_logger;
+	$gist_oembed->set_logger( $gist_oembed_logger );
+	$gist_oembed->run();
+}
 
+/** @todo Can the following two functions be made static methods of the debug
+ * bar class, since there is already an inherent dependency? */
+
+// Late priority to give Debug Bar plugin chance to initialise
+add_action( 'plugins_loaded', 'blazer_six_gist_oembed_add_debug_bar_panel_support', 15 );
 /**
- * The main plugin class.
+ * Add optional support for Debug Bar plugin, if enabled
  *
- * @since 1.0.0
+ * @return null Return early if Debug Bar plugin not enabled.
  */
-class Blazer_Six_Gist_oEmbed {
-	/**
-	 * @access private
-	 * @var Blazer_Six_Gist_oEmbed
-	 */
-	private static $instance;
-	
-	/**
-	 * Basic log for debug messages.
-	 *
-	 * @access protected
-	 * @var array
-	 */
-	protected $debug_log = array();
-	
-	/**
-	 * Key for grouping debug messages by shortcode.
-	 *
-	 * @access protected
-	 * @var int
-	 */
-	protected $debug_log_key = 0;
-	
-	/**
-	 * Toggle to short-circuit shortcode output and expire its corresponding
-	 * transient so output can be regenerated the next time it is run.
-	 *
-	 * @access protected
-	 * @var bool
-	 */
-	protected $expire_transients = false;
-	
-	/**
-	 * Main Blazer_Six_Gist_oEmbed instance.
-	 *
-	 * @since 1.1.0
-	 */
-	public static function instance() {
-		if ( ! self::$instance ) {
-			self::$instance = new self();
-		}
-		
-		return self::$instance;
+function blazer_six_gist_oembed_add_debug_bar_panel_support() {
+	if ( ! class_exists( 'Debug_Bar' ) || is_admin() || ! is_admin_bar_showing() ) {
+		return;
 	}
-	
-	/**
-	 * Set up the plugin.
-	 *
-	 * Adds a [gist] shortcode to do the bulk of the heavy lifting. An embed
-	 * handler is registered to mimic oEmbed functionality, but it relies on
-	 * the shortcode for processing.
-	 *
-	 * Old URL Format: https://gist.github.com/{{id}}#file_{{filename}}
-	 * New URL Format: https://gist.github.com/{{id}}#file-{{file_slug}}
-	 *
-	 * @since 1.1.0
-	 */
-	private function __construct() {
-		// File matching is maintained for backward compatibility, but won't work for the new Gist "bookmark" URLs.
-		wp_embed_register_handler( 'gist', '#(https://gist\.github\.com/([a-z0-9]+))(?:\#file_(.*))?#i', array( $this, 'wp_embed_handler' ) );
-		add_shortcode( 'gist', array( $this, 'shortcode' ) );
-		
-		add_action( 'init', array( $this, 'init' ) );
-		add_action( 'post_updated', array( $this, 'expire_gist_transients' ), 10, 3 );
 
-		if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
-			add_filter( 'debug_bar_panels', array( $this, 'add_debug_bar_panel' ) );
-		}
-	}
-	
-	/**
-	 * Register the Gist stylesheet so it can be embedded once.
-	 *
-	 * @since 1.0.0
-	 */
-	public function init() {
-		wp_register_style( 'github-gist', get_option( 'blazersix_gist_embed_stylesheet' ) );	
-	}
-	
-	/**
-	 * WP embed handler to generate a shortcode string from a Gist URL.
-	 *
-	 * Parses Gist URLs for oEmbed support. Returns the value as a shortcode
-	 * string to let the shortcode method handle processing. The value
-	 * returned also doesn't have wpautop() applied, which is a must for
-	 * source code.
-	 *
-	 * @since 1.0.0
-	 */
-	public function wp_embed_handler( $matches, $attr, $url, $rawattr ) {
-		$shortcode = '[gist';
-		
-		if ( isset( $matches[2] ) && ! empty( $matches[2] ) ) {
-			$shortcode .= ' id="' . esc_attr( $matches[2] ) . '"';
-		}
-		
-		// For backward compatibility.
-		if ( isset( $matches[3] ) && ! empty( $matches[3] ) ) {
-			$shortcode .= ' file="' . esc_attr( $matches[3] ) . '"';
-		}
-		
-		$shortcode .= ']';
-		
-		return $shortcode;
-	}
-	
-	/**
-	 * Gist shortcode.
-	 *
-	 * Works with secret Gists, too.
-	 *
-	 * Shortcode attributes:
-	 *
-	 * - id - The Gist id (found in the URL). The only required attribute.
-	 * - embed_stylesheet - Whether the external stylesheet should be enqueued for output in the footer.
-	 *     * If the footer is too late, set to false and enqueue the 'github-gist' style before 'wp_head'.
-	 *     * Any custom styles should be added to the theme's stylesheet.
-	 * - file - Name of a specific file in a Gist.
-	 * - highlight - Comma-separated list of line numbers to highlight.
-	 *     * Ranges can be specified. Ex: 2,4,6-10,12
-	 * - highlight_color - Background color of highlighted lines.
-	 *     * To change it globally, hook into the filter any supply a different color.
-	 * - lines - A range of lines to limit the Gist to.
-	 *     * Suited for single file Gists or shortcodes using the 'file' attribute.
-	 * - show_line_numbers - Whether line numbers should be displayed.
-	 * - show_meta - Whether the trailing meta information in default Gist embeds should be displayed.
-	 *
-	 * @since 1.0.0
-	 *
-	 * @param array $attr Attributes of the shortcode.
-	 * @return string HTML content to display the Gist.
-	 */
-	public function shortcode( $attr ) {
-		global $post;
-		
-		$defaults = apply_filters( 'blazersix_gist_shortcode_defaults', array(
-			'embed_stylesheet'  => apply_filters( 'blazersix_gist_embed_stylesheet_default', true ),
-			'file'              => '',
-			'highlight'         => array(),
-			'highlight_color'   => apply_filters( 'blazersix_gist_embed_highlight_color', '#ffffcc' ),
-			'id'                => '',
-			'lines'             => '',
-			'show_line_numbers' => true,
-			'show_meta'         => true
-		) );
-		
-		// Sanitize attributes.
-		$attr = shortcode_atts( $defaults, $attr );
-		$attr['embed_stylesheet'] = $this->shortcode_bool( $attr['embed_stylesheet'] );
-		$attr['show_line_numbers'] = $this->shortcode_bool( $attr['show_line_numbers'] );
-		$attr['show_meta'] = $this->shortcode_bool( $attr['show_meta'] );
-		$attr['highlight'] = $this->parse_highlight_arg( $attr['highlight'] );
-		$attr['lines'] = $this->parse_line_number_arg( $attr['lines'] );
-		
-		// Short-circuit the shortcode output and just expire the transient.
-		// This is set to true when posts are updated.
-		if ( $this->expire_transients ) {
-			$this->expire_gist_transient( $attr );
-			return;
-		}
-		
-		if ( ! empty( $attr['id'] ) ) {
-			$url = 'https://gist.github.com/' . $attr['id'];
-			$json_url = $url . '.json';
-		}
-		
-		// Bail if the JSON endpoint couldn't be determined.
-		if ( ! isset( $json_url ) ) {
-			return '';
-		}
-		
-		if ( $json_url && isset( $post->ID ) ) {
-			$html = $this->get_gist_html( $json_url, $attr );
-			
-			if ( '{{unknown}}' === $html ) {
-				return $wp_embed->maybe_make_link( $url );
-			}
-			
-			// If there was a result, return it.
-			if ( $html ) {
-				if ( $attr['embed_stylesheet'] ) {
-					wp_enqueue_style( 'github-gist' );
-				}
-				
-				$html = apply_filters( 'blazersix_gist_embed_html', $html, $url, $attr, $post->ID );
-				
-				$this->debug_log( $attr );
-				$this->debug_log( $html );
-				$this->debug_log_key ++;
-				
-				return $html;
-			}
-		}
-		
-		return '';
-	}
-	
-	/**
-	 * Helper method to determine if a shortcode attribute is true or false.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string|int|bool $var Attribute value.
-	 * @return bool
-	 */
-	public function shortcode_bool( $var ) {
-		$falsey = array( 'false', '0', 'no', 'n' );
-		return ( ! $var || in_array( strtolower( $var ), $falsey ) ) ? false : true;
-	}
-	
-	/**
-	 * Parses and expands the shortcode 'highlight' attribute and returns it
-	 * in a usable format.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $line_numbers Comma-separated list of line numbers and ranges.
-	 * @return array List of line numbers.
-	 */
-	public function parse_highlight_arg( $line_numbers ) {
-		if ( empty( $line_numbers ) ) {
-			return null;
-		}
-		
-		// Determine which lines should be highlighted.
-		$highlight = explode( ',', $line_numbers );
-		
-		// Convert any ranges.
-		foreach ( $highlight as $key => $num ) {
-			if ( false !== strpos( $num, '-' ) ) {
-				unset( $highlight[ $key ] );
-				
-				$range = explode( '-', $num );
-				$highlight += range( $range[0], $range[1] );
-			}
-		}
-		
-		return array_unique( $highlight );
-	}
-	
-	/**
-	 * Parses the shortcode 'lines' attribute into min and max values.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $line_numbers Range of line numbers separated by a dash.
-	 * @return array Array with min and max line numbers.
-	 */
-	public function parse_line_number_arg( $line_numbers ) {
-		if ( empty( $line_numbers ) ) {
-			return array( 'min' => 0, 'max' => 0 );
-		}
-		
-		if ( false === strpos( $line_numbers, '-' ) ) {
-			$range = array_fill_keys( array( 'min', 'max' ), absint( $line_numbers ) );
-		} else {
-			$numbers = array_map( 'absint', explode( '-', $line_numbers ) );
-			
-			$range = array(
-				'min' => $numbers[0],
-				'max' => $numbers[1]
-			);
-		}
-		
-		return $range;
-	}
-	
-	/**
-	 * Retrieve Gist HTML.
-	 *
-	 * Gist HTML can come from one of three different sources:
-	 * - Remote JSON endpoint.
-	 * - Transient.
-	 * - Post meta cache.
-	 *
-	 * When a Gist is intially requested, the HTML is fetched from the JSON
-	 * endpoint and cached in a post meta field. It is then processed to limit
-	 * line numbers, highlight specific lines, and add a few extra classes as
-	 * style hooks. The processed HTML is then stored in a transient using a
-	 * hash of the shortcodes attributes for the key.
-	 *
-	 * On subsequent requests, the HTML is fetched from the transient until it
-	 * expires, then it is requested from the remote URL again.
-	 *
-	 * In the event the HTML can't be fetched from the remote endpoint and the
-	 * transient is expired, the HTML is retrieved from the post meta backup.
-	 *
-	 * This algorithm allows Gist HTML to stay in sync with any changes GitHub
-	 * may make to their markup, while providing a local cache for faster
-	 * retrieval and a backup in case GitHub can't be reached.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $url The JSON endpoint for the Gist.
-	 * @param array $args List of shortcode attributes.
-	 * @return string Gist HTML or {{unknown}} if it couldn't be determined.
-	 */
-	public function get_gist_html( $url, $args ) {
-		global $post;
-		
-		// Add a specific file from a Gist to the URL.
-		if ( ! empty( $args['file'] ) ) {
-			$url = add_query_arg( 'file', urlencode( $args['file'] ), $url );
-		}
-		
-		$post_meta_key = '_gist_embed_' . md5( $url );
-		$transient_key = 'gist_embed_' . $this->shortcode_hash( 'gist', $args );
-		
-		$html = get_transient( $transient_key );
-		
-		// Retrieve html from Gist JSON endpoint.
-		if ( empty( $html ) ) {
-			$json = $this->fetch_gist( $url );
-			
-			if ( ! empty( $json->div ) ) {
-				$html = $json->div;
-			}
-			
-			// Update the stylesheet reference.
-			if ( ! empty( $json->stylesheet ) ) {
-				update_option( 'blazersix_gist_embed_stylesheet', $json->stylesheet );
-			}
-			
-			// Failures are cached, too. Update the post to attempt to fetch again.
-			$html = ( $html ) ? $html : '{{unknown}}';
-			$transient_expire = 60 * 60 * 24;
-			
-			if ( '{{unknown}}' != $html ) {
-				// Update the post meta fallback.
-				// @link http://core.trac.wordpress.org/ticket/21767
-				update_post_meta( $post->ID, $post_meta_key, addslashes( $html ) );
-				$html = $this->process_gist_html( $html, $args );
-				$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Remote Request', 'blazersix-gist-oembed' ) . '</p>' );
-			} elseif ( $fallback = get_post_meta( $post->ID, $post_meta_key, true ) ) {
-				// Return the fallback instead of {{unknown}}
-				$html = $this->process_gist_html( $fallback, $args );
-				
-				// Cache the fallback for an hour.
-				$transient_expire = 60 * 60;
-				$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Post Meta Fallback', 'blazersix-gist-oembed' ) . '</p>' );
-			} else {
-				$this->debug_log( '<strong style="color: #ee0000">' . __( 'Remote call and transient failed and fallback was empty.', 'blazersix-gist-oembed' ) . '</strong>' );
-			}
-			
-			// Cache the processed HTML.
-			set_transient( $transient_key, $html, $transient_expire );
-		} else {
-			$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Transient Cache', 'blazersix-gist-oembed' ) . '</p>' );
-		}
-		
-		$this->debug_log( '<strong>' . __( 'JSON Endpoint:', 'blazersix-gist-oembed' ) . '</strong> ' . $url );
-		$this->debug_log( '<strong>' . __( 'Post Meta Cache Key:', 'blazersix-gist-oembed' ) . '</strong> ' . $post_meta_key );
-		$this->debug_log( '<strong>' . __( 'Transient Key:', 'blazersix-gist-oembed' ) . '</strong> ' . $transient_key );
-		
-		return $html;
-	}
-	
-	/**
-	 * Fetch Gist data from its JSON endpoint.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $url Gist JSON endpoint.
-	 * @return object|bool Gist JSON object or false.
-	 */
-	public function fetch_gist( $url ) {
-		$this->debug_log( '<strong>' . __( 'Doing remote request:', 'blazersix-gist-oembed' ) . '</strong><br>' . $url );
-		
-		$response = wp_remote_get( $url, array( 'sslverify' => false ) );
-		
-		if ( 200 == wp_remote_retrieve_response_code( $response ) ) {
-			return json_decode( wp_remote_retrieve_body( $response ) );
-		}
-		
-		return false;
-	}
-	
-	/**
-	 * Process the HTML returned from a Gist's JSON endpoint based on settings
-	 * passed through the shortcode.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $html HTML from the Gist's JSON endpoint.
-	 * @param array $args List of shortcode attributes.
-	 * @return string Modified HTML.
-	 */
-	public function process_gist_html( $html, $args ) {
-		// Remove the line number cell if it has been disabled.
-		if ( ! $args['show_line_numbers'] ) {
-			$html = preg_replace( '#<td class="line_numbers">.*?</td>#s', '', $html );
-		}
-		
-		// Remove the meta section if it has been disabled.
-		if ( ! $args['show_meta'] ) {
-			$html = preg_replace( '#<div class="gist-meta">.*?</div>#s', '', $html );
-		}
-		
-		$lines_pattern = '#(<td class="line_data"[^>]+>)(.+?)</td>#s';
-		preg_match( $lines_pattern, $html, $lines_matches );
-		
-		if( ! empty( $lines_matches[2] ) ) {
-			// Restrict the line number display if a range has been specified.
-			if ( $args['show_line_numbers'] && $args['lines']['min'] && $args['lines']['max'] ) {
-				$html = $this->limit_gist_line_numbers( $html, $args['lines'] );
-			}
-			
-			if ( ! empty( $args['highlight'] ) ) {
-				// Flip to use isset() when looping through the lines.
-				$highlight = array_flip( $args['highlight'] );
-			}
-			
-			// Extract and cleanup the individual lines from the Gist HTML into an array for processing.
-			$lines = trim( $lines_matches[2] );
-			$lines = preg_split( '#</pre>[\s]*<pre>#', substr( $lines, 5, strlen( $lines ) - 6 ) );
-			
-			foreach ( $lines as $key => $line ) {
-				// Remove lines if they're not in the specified range and continue.
-				if ( ( $args['lines']['min'] && $key < $args['lines']['min'] - 1 ) || ( $args['lines']['max'] && $key > $args['lines']['max'] - 1 ) ) {
-					unset( $lines[ $key ] );
-					continue;
-				}
-				
-				// Add classes for styling.
-				$classes = array( 'pre-line' );
-				$classes[] = ( $key % 2 ) ? 'pre-line-odd' : 'pre-line-even';
-				$style = '';
-				
-				if ( isset( $highlight[ $key + 1 ] ) ) {
-					$classes[] = 'pre-line-highlight';
-					
-					if ( ! empty( $args['highlight_color'] ) ) {
-						$style = ' style="background-color: ' . $args['highlight_color'] . ' !important"';
-					}
-				}
-				
-				$prepend = '<pre class="' . join( ' ', $classes ) . '"' . $style . '>';
-				
-				$lines[ $key ] = $prepend . $line . '</pre>';
-			}
-			
-			$replacement = $lines_matches[1] . join( "\n", $lines ) . '</td>';
-			$html = preg_replace( $lines_pattern, $replacement, $html, 1 );
-		}
-		
-		return $html;
-	}
-	
-	/**
-	 * Removes line numbers from the Gist's HTML that fall outside the
-	 * supplied range.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param string $html HTML from the Gist's JSON endpoint.
-	 * @param array $range Array of min and max values.
-	 * @return string Modified HTML.
-	 */
-	public function limit_gist_line_numbers( $html, $range ) {
-		// Limit the line numbers that should show.
-		$line_num_pattern = '#(<td class="line_numbers">)(.*?)</td>#s';
-		
-		preg_match( $line_num_pattern, $html, $line_num_matches );
-		
-		if ( $line_num_matches[2] ) {
-			$line_numbers = array_slice( explode( "\n", trim( $line_num_matches[2] ) ), $range['min'] - 1, $range['max'] - $range['min'] + 1 );
-			
-			$replacement = $line_num_matches[1] . join( "\n", $line_numbers ) . '</td>';
-			$html = preg_replace( $line_num_pattern, $replacement, $html, 1 );
-		}
-		
-		return $html;
-	}
-	
-	/**
-	 * Removes transients associated with Gists embedded in a post.
-	 *
-	 * Retrieves the keys of meta data associated with a post and deletes any
-	 * transients with a matching embed key.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param int $post_id Post ID.
-	 * @param WP_Post $post_after Post object after update.
-	 * @param WP_Post $post_before Post object before update.
-	 */
-	public function expire_gist_transients( $post_id, $post_after, $post_before ) {
-		$this->expire_transients = true;
-		
-		// Run the shorcodes to clear associated transients.
-		do_shortcode( $post_after->post_content );
-		do_shortcode( $post_before->post_content );
-	}
-	
-	/**
-	 * Expire the transient associated with a particular shortcode so its HTML
-	 * will be regenerated the next time it is requested.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param array $args List of shortcode attributes.
-	 */
-	public function expire_gist_transient( $args ) {
-		$key = 'gist_embed_' . $this->shortcode_hash( 'gist', $args );
-		set_transient( $key, null, -1 );
-	}
-	
-	/**
-	 * Get the debug log property.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @return array
-	 */
-	public function get_debug_log() {
-		return $this->debug_log;
-	}
-	
-	/**
-	 * Simple debug logger.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param mixed $value A value to log for the current shortcode.
-	 */
-	protected function debug_log( $value ) {
-		if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
-			$this->debug_log[ $this->debug_log_key ][] = $value;
-		}
-	}
-	
-	/**
-	 * Sort a shortcode's attributes by name and hash it for use as a cache
-	 * key.
-	 *
-	 * @since 1.1.0
-	 */
-	protected function shortcode_hash( $tag, $args ) {
-		ksort( $args );
-		return md5( $tag . '_' . serialize( $args ) );
-	}
-	
-	/**
-	 * Add a custom panel to the debug bar.
-	 *
-	 * @since 1.1.0
-	 *
-	 * @param array $panels List of panels.
-	 * @return array
-	 */
-	public function add_debug_bar_panel( $panels ) {
-		if ( ! class_exists( 'Blazer_Six_Gist_oEmbed_Debug_Bar_Panel' ) ) {
-			include( plugin_dir_path( __FILE__ ) . 'class-blazer-six-gist-oembed-debug-bar-panel.php' );
-			$panels[] = new Blazer_Six_Gist_oEmbed_Debug_Bar_Panel();
-		}
-		
-		return $panels;
-	}
-}
\ No newline at end of file
+	add_filter( 'debug_bar_panels', 'blazer_six_gist_oembed_add_debug_bar_panel' );
+}
+
+/**
+ * Add instance of our debug bar panel to Debug Bar plugin.
+ *
+ * @param array $panels
+ *
+ * @return Blazer_Six_Gist_oEmbed_Debug_Bar_Panel
+ */
+function blazer_six_gist_oembed_add_debug_bar_panel( array $panels ) {
+	global $gist_oembed_logger;
+//	wp_die('panel being added');
+	if ( ! class_exists( 'Blazer_Six_Gist_oEmbed_Debug_Bar_Panel' ) ) {
+		require( plugin_dir_path( __FILE__ ) . 'class-blazer-six-gist-oembed-debug-bar-panel.php' );
+	}
+	$panels[] = new Blazer_Six_Gist_oEmbed_Debug_Bar_Panel( $gist_oembed_logger );
+	return $panels;
+}
diff --git a/class-blazer-six-gist-oembed-debug-bar-panel.php b/class-blazer-six-gist-oembed-debug-bar-panel.php
index dee7b27..f230d2a 100644
--- a/class-blazer-six-gist-oembed-debug-bar-panel.php
+++ b/class-blazer-six-gist-oembed-debug-bar-panel.php
@@ -1,86 +1,84 @@
 <?php
+/**
+ * Blazer Six Gist oEmbed
+ *
+ * @package BlazerSix\GistoEmbed
+ * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <gary@garyjones.co.uk>
+ * @copyright Copyright (c) 2012, Blazer Six, Inc.
+ * @license GPL-2.0+
+ */
+
 /**
  * Class for displaying a custom panel on the debug bar with information about
  * Gist shortcodes used in a post.
  *
- * @since 1.1.0
+ * @package BlazerSix\GistoEmbed
+ * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <gary@garyjones.co.uk>
  */
 class Blazer_Six_Gist_oEmbed_Debug_Bar_Panel extends Debug_Bar_Panel {
+	/** @var object Logger object. */
+	protected $logger;
+
+	/**
+	 * Assign properties, and call parent constructor.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param object $logger
+	 */
+	public function __construct( $logger ) {
+		$this->logger = $logger;
+		parent::__construct();
+	}
+
 	/**
 	 * Initialize the panel and set its title.
 	 *
 	 * @since 1.1.0
 	 */
-	public function init(){
+	public function init() {
 		$this->title( __( 'Gist oEmbed', 'blazersix-gist-oembed' ) );
 	}
 
 	/**
-	 * Make the panel visibile.
+	 * Make the panel visible, only if there is something to display.
 	 *
 	 * @since 1.1.0
 	 */
 	public function prerender() {
-		$this->set_visible( true );
+		$logs = $this->logger->get_logs();
+		$this->set_visible( ! empty( $logs ) );
 	}
 
 	/**
-	 * Requests the debug log from the Gist oEmbed class and displays it in
-	 * the custom debug bar panel.
+	 * Request the log from the logger class and display it in the custom debug
+	 * bar panel.
 	 *
 	 * @since 1.1.0
 	 */
 	public function render() {
-		$gists = Blazer_Six_Gist_oEmbed::instance();
-		
-		$log = $gists->get_debug_log();
-		
-		foreach ( $log as $gist ) {
+		$logs = $this->logger->get_logs();
+		foreach ( $logs as $log_id => $gist ) {
 			echo '<div class="b6go-gist-debug">';
-				foreach ( $gist as $entry ) {
-					if ( is_scalar( $entry ) ) {
-						echo ( false === strpos( $entry, '<table' ) ) ? wpautop ( $entry ) : $entry;
-					} elseif ( is_array( $entry ) ) {
-						?>
-						<table>
-							<thead>
-								<tr>
-									<th><?php _e( 'Attribute', 'blazersix-gist-oembed' ); ?></th>
-									<th><?php _e( 'Value', 'blazersix-gist-oembed' ); ?></th>
-								</tr>
-							</thead>
-							<tbody>
-								<?php foreach ( $entry as $key => $value ) : ?>
-									<tr>
-										<th><?php echo esc_html( $key ); ?></th>
-										<td><?php echo ( is_scalar( $value ) ) ? $value : print_r( $value, true ); ?></td>
-									</tr>
-								<?php endforeach; ?>
-							</tbody>
-						</table>
-						<?php
-					}
-				}
+			foreach ( $gist as $entry ) {
+				// Don't wpautop tabular data, as it adds <br> between line number spans.
+				echo ( false === strpos( $entry['message'], '<table' ) ) ? wpautop ( $entry['message'] ) : $entry['message'];
+			}
 			echo '</div>';
 		}
 		?>
 		<style type="text/css">
-		.b6go-gist-debug { margin: 0 0 20px 0; padding: 10px; background: #e8e8e8;}
-		.b6go-gist-debug p { margin: 0 0 10px 0;}
-		.b6go-gist-debug p.source { padding: 5px; background: #ffffdd;}
-		.b6go-gist-debug table { margin: 0 0 10px 0;}
-		.b6go-gist-debug td { padding: 3px 5px;}
-		.b6go-gist-debug th { padding: 3px 5px; font-weight: bold;}
-		.b6go-gist-debug thead th { background: #dfdfdf; border-bottom: 1px solid #ccc;}
-		.b6go-gist-debug .gist table { margin: 0;}
-		#querylist .b6go-gist-debug .gist .gist-file .gist-data .line_data { padding: 0;}
-		#querylist .b6go-gist-debug .gist .gist-file .gist-data .line_data pre { overflow: auto; margin: 0; padding: 0;
-			white-space: pre;
+		.b6go-gist-debug { margin: 2em 0; padding: 10px; background: #e8e8e8;}
+		#querylist .b6go-gist-debug .gist .gist-file .gist-data .line_data pre {
+			overflow: auto;
 			word-wrap: normal;
 			-moz-tab-size: 4;
 			-o-tab-size: 4;
 			tab-size: 4;}
-		#querylist .b6go-gist-debug .gist .gist-file .gist-data .line_data .line { padding: 0 0.5em;}
+		.b6go-gist-debug .gist .gist-file .gist-data .line_numbers span {font-size: 12px;}
+		#querylist .b6go-gist-debug h2 {border: 0; float: none; font-size: 22px; text-align: left; margin: 0 !important; padding-left: 0;}
 		</style>
 		<?php
 	}
diff --git a/class-blazer-six-gist-oembed-log.php b/class-blazer-six-gist-oembed-log.php
new file mode 100644
index 0000000..078fadf
--- /dev/null
+++ b/class-blazer-six-gist-oembed-log.php
@@ -0,0 +1,111 @@
+<?php
+/**
+ * Blazer Six Gist oEmbed
+ *
+ * @package BlazerSix\GistoEmbed
+ * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <garyy@garyjones.co.uk>
+ * @copyright Copyright (c) 2012, Blazer Six, Inc.
+ * @license GPL-2.0+
+ */
+
+/**
+ * Logging class.
+ *
+ * This class handles the recording of log messages - in particular, messages at
+ * the debug level.
+ *
+ * It follows a subset of PSR-3 and when WordPress bumps to PHP 5.3 as
+ * its minimum, then it can implement Psr\Log\LoggerInterface with minimal
+ * changes to the interface. Note however, that code in this file doesn't
+ * interact directly with WordPress at all.
+ *
+ * @see https://github.com/php-fig/log
+ *
+ * @package BlazerSix\GistoEmbed
+ * @author Gary Jones <garyy@garyjones.co.uk>
+ * @author Brady Vercher <brady@blazersix.com>
+ */
+class Blazer_Six_Gist_oEmbed_Log {
+	/**
+	 * Holds the log messages and contextual data.
+	 *
+	 * The format is something like the following:
+	 *
+	 * $logs = array(
+	 *     'fookey' => array(
+	 *         array(
+	 *             'message' => 'Some message.',
+	 *             'qwe'     => 'rty';
+	 *         ),
+	 *         array(
+	 *             'message' => 'Another message for the same gist shortcode.',
+	 *             'extra'     => 'data';
+	 *             'if'     => 'needed';
+	 *         ),
+	 *     ),
+	 *     'barkey' => array(
+	 *         array(
+	 *             'message' => 'Some message for gist bar.',
+	 *             'qwe'     => 'rty';
+	 *         ),
+	 *         array(
+	 *             'message' => 'Another message for gist bar.',
+	 *             'extra'     => 'data';
+	 *             'if'     => 'needed';
+	 *         ),
+	 *     ),
+	 * );
+	 */
+	protected $logs = array();
+
+	/**
+	 * Detailed debug information.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @uses Blazer_Six_Gist_oEmbed_Log::log()
+	 *
+	 * @param string $message
+	 * @param array  $context
+	 */
+	public function debug( $message, array $context = array() ) {
+		$this->log( 'debug', $message, $context );
+	}
+
+	/**
+	 * Log with an arbitrary level.
+	 *
+	 * Include a 'key' key in the $context argument to group log messages
+	 * together. If none is provided, the message is grouped by itself under an
+	 * md5() hash of the message itself.
+	 *
+	 * Note that at this point in time, we don't actually do anything with the
+	 * $level argument.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param mixed  $level
+	 * @param string $message
+	 * @param array  $context
+	 */
+	public function log( $level, $message, array $context = array() ) {
+		$context['message'] = $message;
+		$key = isset( $context['key'] ) ? $context['key'] : md5( $message );
+		unset( $context['key'] );
+		$this->logs[$key][] = $context;
+	}
+
+	/**
+	 * Return recorded logs data.
+	 *
+	 * Under PSR-1, this method would be called getLogs().
+	 *
+	 * @since 1.1.0
+	 *
+	 * @return array
+	 */
+	public function get_logs() {
+		return $this->logs;
+	}
+}
\ No newline at end of file
diff --git a/class-blazer-six-gist-oembed.php b/class-blazer-six-gist-oembed.php
new file mode 100644
index 0000000..a19ba67
--- /dev/null
+++ b/class-blazer-six-gist-oembed.php
@@ -0,0 +1,579 @@
+<?php
+/**
+ * Blazer Six Gist oEmbed
+ *
+ * @package BlazerSix/GistoEmbed
+ * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <gary@garyjones.co.uk>
+ * @copyright Copyright (c) 2012, Blazer Six, Inc.
+ * @license GPL-2.0+
+ *
+ * @todo Feed support: link directly to post, directly to Gist, or wrap in iframe?
+ * @todo Cache the style sheet locally.
+ */
+
+/**
+ * The main plugin class.
+ *
+ * @package BlazerSix/GistoEmbed
+ * @author Brady Vercher <brady@blazersix.com>
+ * @author Gary Jones <gary@garyjones.co.uk>
+ */
+class Blazer_Six_Gist_oEmbed {
+	/** @var object Logger object. */
+	protected $logger = null;
+
+	/**
+	 * Toggle to short-circuit shortcode output and expire its corresponding
+	 * transient so output can be regenerated the next time it is run.
+	 *
+	 * @var bool
+	 */
+	protected $expire_transients = false;
+
+	/**
+	 * Sets a logger instance on the object.
+	 *
+	 * Since logging is optional, the dependcy injection is done via this
+	 * method, instead of being required through a constructor.
+	 *
+	 * Under PSR-1, this method would be called setLogger().
+	 *
+	 * @see https://github.com/php-fig/log/blob/master/Psr/Log/LoggerAwareInterface.php
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param object $logger
+	 */
+	public function set_logger( $logger ) {
+		$this->logger = $logger;
+	}
+
+	/**
+	 * Return logger instance.
+	 *
+	 * Under PSR-1, this method would be called getLogger().
+	 *
+	 * @since 1.1.0
+	 *
+	 * @return object
+	 */
+	public function get_logger() {
+		return $this->$logger;
+	}
+
+	/**
+	 * Set up the plugin.
+	 *
+	 * Adds a [gist] shortcode to do the bulk of the heavy lifting. An embed
+	 * handler is registered to mimic oEmbed functionality, but it relies on
+	 * the shortcode for processing.
+	 *
+	 * Old URL Format: https://gist.github.com/{{id}}#file_{{filename}}
+	 * New URL Format: https://gist.github.com/{{id}}#file-{{file_slug}}
+	 *
+	 * @since 1.1.0
+	 */
+	public function run() {
+		// File matching is maintained for backward compatibility, but won't work for the new Gist "bookmark" URLs.
+		wp_embed_register_handler( 'gist', '#(https://gist\.github\.com/([a-z0-9]+))(?:\#file_(.*))?#i', array( $this, 'wp_embed_handler' ) );
+		add_shortcode( 'gist', array( $this, 'shortcode' ) );
+
+		add_action( 'wp_enqueue_scripts', array( $this, 'style' ) );
+		add_action( 'post_updated', array( $this, 'expire_gist_transients' ), 10, 3 );
+	}
+
+	/**
+	 * Register the Gist style sheet so it can be embedded once.
+	 *
+	 * @since 1.0.0
+	 */
+	public function style() {
+		wp_register_style( 'github-gist', get_option( 'blazersix_gist_embed_stylesheet' ) );
+	}
+
+	/**
+	 * WP embed handler to generate a shortcode string from a Gist URL.
+	 *
+	 * Parses Gist URLs for oEmbed support. Returns the value as a shortcode
+	 * string to let the shortcode method handle processing. The value
+	 * returned also doesn't have wpautop() applied, which is a must for
+	 * source code.
+	 *
+	 * @since 1.0.0
+	 */
+	public function wp_embed_handler( $matches, $attr, $url, $rawattr ) {
+		$shortcode = '[gist';
+
+		if ( isset( $matches[2] ) && ! empty( $matches[2] ) ) {
+			$shortcode .= ' id="' . esc_attr( $matches[2] ) . '"';
+		}
+
+		// For backward compatibility.
+		if ( isset( $matches[3] ) && ! empty( $matches[3] ) ) {
+			$shortcode .= ' file="' . esc_attr( $matches[3] ) . '"';
+		}
+
+		// This attribute added so we can identify if a oembed URL or direct shortcode was used.
+		$shortcode .= ' oembed="1"]';
+
+		return $shortcode;
+	}
+
+	/**
+	 * Gist shortcode.
+	 *
+	 * Works with secret Gists, too.
+	 *
+	 * Shortcode attributes:
+	 *
+	 * - id - The Gist id (found in the URL). The only required attribute.
+	 * - embed_stylesheet - Whether the external style sheet should be enqueued for output in the footer.
+	 *     * If the footer is too late, set to false and enqueue the 'github-gist' style before 'wp_head'.
+	 *     * Any custom styles should be added to the theme's style sheet.
+	 * - file - Name of a specific file in a Gist.
+	 * - highlight - Comma-separated list of line numbers to highlight.
+	 *     * Ranges can be specified. Ex: 2,4,6-10,12
+	 * - highlight_color - Background color of highlighted lines.
+	 *     * To change it globally, hook into the filter and supply a different color.
+	 * - lines - A range of lines to limit the Gist to.
+	 *     * Suited for single file Gists or shortcodes using the 'file' attribute.
+	 * - show_line_numbers - Whether line numbers should be displayed.
+	 * - show_meta - Whether the trailing meta information in default Gist embeds should be displayed.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param array $attr Attributes of the shortcode.
+	 *
+	 * @return string HTML content to display the Gist.
+	 */
+	public function shortcode( $attr ) {
+		global $post;
+
+		// Rebuild the original shortcode as a string with raw attributes
+		$rawattr = array();
+		foreach ( $attr as $key => $value ) {
+			if ( 'oembed' != $key ) {
+				$rawattr[] = $key . '="' . $value . '"';
+			}
+		}
+		$shortcode = '[gist ' . implode(' ', $rawattr) . ']';
+
+		$defaults = apply_filters(
+			'blazersix_gist_shortcode_defaults',
+			array(
+				'embed_stylesheet'  => apply_filters( 'blazersix_gist_embed_stylesheet_default', true ),
+				'file'              => '',
+				'highlight'         => array(),
+				'highlight_color'   => apply_filters( 'blazersix_gist_embed_highlight_color', '#ffffcc' ),
+				'id'                => '',
+				'lines'             => '',
+				'show_line_numbers' => true,
+				'show_meta'         => true,
+				'oembed'            => 0, // private use only
+			)
+		);
+
+		// Sanitize attributes.
+		$attr = shortcode_atts( $defaults, $attr );
+		$attr['embed_stylesheet']  = $this->shortcode_bool( $attr['embed_stylesheet'] );
+		$attr['show_line_numbers'] = $this->shortcode_bool( $attr['show_line_numbers'] );
+		$attr['show_meta']         = $this->shortcode_bool( $attr['show_meta'] );
+		$attr['highlight']         = $this->parse_highlight_arg( $attr['highlight'] );
+		$attr['lines']             = $this->parse_line_number_arg( $attr['lines'] );
+
+		// Log what we're dealing with - title uses original attributes, but hashed against processed attributes.
+		$this->debug_log( '<h2>' . $shortcode . '</h2>', $this->shortcode_hash( 'gist', $attr ) );
+
+		// Short-circuit the shortcode output and just expire the transient.
+		// This is set to true when posts are updated.
+		if ( $this->expire_transients ) {
+			$this->expire_gist_transient( $attr );
+			return;
+		}
+
+		// Bail if the ID is not set.
+		if ( empty( $attr['id'] ) ) {
+			$this->debug_log( __( 'Shortcode did not have a required id attribute.', 'blazer_six_gist_oembed' ), $this->shortcode_hash( 'gist', $attr ) );
+			return '';
+		}
+
+		$url = 'https://gist.github.com/' . $attr['id'];
+		$json_url = $url . '.json';
+
+		if ( isset( $post->ID ) ) {
+			$html = $this->get_gist_html( $json_url, $attr );
+
+			if ( '{{unknown}}' === $html ) {
+				return;
+				/** @todo Get reference to $wp_embed. Global? */
+				return $wp_embed->maybe_make_link( $url );
+			}
+
+			// If there was a result, return it.
+			if ( $html ) {
+				if ( $attr['embed_stylesheet'] ) {
+					wp_enqueue_style( 'github-gist' );
+				}
+
+				$html = apply_filters( 'blazersix_gist_embed_html', $html, $url, $attr, $post->ID );
+
+				foreach ( $attr as $key => $value ) {
+					$message  = '<strong>' . $key . __(' (shortcode attribute)', 'blazer_six_gist_oembed') . ':</strong> ';
+					$message .= is_scalar( $value ) ? $value : print_r( $value, true );
+					$this->debug_log( $message, $this->shortcode_hash( 'gist', $attr ) );
+				}
+				$this->debug_log( '<strong>Gist:</strong><br />' . $html, $this->shortcode_hash( 'gist', $attr ) );
+
+				return $html;
+			}
+		}
+		return '';
+	}
+
+	/**
+	 * Helper method to determine if a shortcode attribute is true or false.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string|int|bool $var Attribute value.
+	 *
+	 * @return bool
+	 */
+	public function shortcode_bool( $var ) {
+		$falsey = array( 'false', '0', 'no', 'n' );
+		return ( ! $var || in_array( strtolower( $var ), $falsey ) ) ? false : true;
+	}
+
+	/**
+	 * Parses and expands the shortcode 'highlight' attribute and returns it
+	 * in a usable format.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $line_numbers Comma-separated list of line numbers and ranges.
+	 *
+	 * @return array|null List of line numbers, or null if no line numbers given
+	 */
+	public function parse_highlight_arg( $line_numbers ) {
+		if ( empty( $line_numbers ) ) {
+			return null;
+		}
+
+		// Determine which lines should be highlighted.
+		$highlight = array_map('trim', explode( ',', $line_numbers ));
+
+		// Convert any ranges.
+		foreach ( $highlight as $index => $num ) {
+			if ( false !== strpos( $num, '-' ) ) {
+				unset( $highlight[ $index ] );
+
+				$range = array_map( 'trim', explode( '-', $num ) );
+				foreach ( range( $range[0], $range[1] ) as $line ) {
+					array_push($highlight, $line);
+				}
+			}
+		}
+		return array_unique( $highlight );
+	}
+
+	/**
+	 * Parses the shortcode 'lines' attribute into min and max values.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $line_numbers Range of line numbers separated by a dash.
+	 *
+	 * @return array Array with min and max line numbers.
+	 */
+	public function parse_line_number_arg( $line_numbers ) {
+		if ( empty( $line_numbers ) ) {
+			return array( 'min' => 0, 'max' => 0, );
+		}
+
+		if ( false === strpos( $line_numbers, '-' ) ) {
+			$range = array_fill_keys( array( 'min', 'max', ), absint( trim( $line_numbers ) ) );
+		} else {
+			$numbers = array_map( 'absint', array_map( 'trim', explode( '-', $line_numbers ) ) );
+
+			$range = array(
+				'min' => $numbers[0],
+				'max' => $numbers[1],
+			);
+		}
+
+		return $range;
+	}
+
+	/**
+	 * Retrieve Gist HTML.
+	 *
+	 * Gist HTML can come from one of three different sources:
+	 * - Remote JSON endpoint.
+	 * - Transient.
+	 * - Post meta cache.
+	 *
+	 * When a Gist is intially requested, the HTML is fetched from the JSON
+	 * endpoint and cached in a post meta field. It is then processed to limit
+	 * line numbers, highlight specific lines, and add a few extra classes as
+	 * style hooks. The processed HTML is then stored in a transient using a
+	 * hash of the shortcodes attributes for the key.
+	 *
+	 * On subsequent requests, the HTML is fetched from the transient until it
+	 * expires, then it is requested from the remote URL again.
+	 *
+	 * In the event the HTML can't be fetched from the remote endpoint and the
+	 * transient is expired, the HTML is retrieved from the post meta backup.
+	 *
+	 * This algorithm allows Gist HTML to stay in sync with any changes GitHub
+	 * may make to their markup, while providing a local cache for faster
+	 * retrieval and a backup in case GitHub can't be reached.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $url  The JSON endpoint for the Gist.
+	 * @param array  $args List of shortcode attributes.
+	 *
+	 * @return string Gist HTML or {{unknown}} if it couldn't be determined.
+	 */
+	public function get_gist_html( $url, $args ) {
+		global $post;
+
+		// Add a specific file from a Gist to the URL.
+		if ( ! empty( $args['file'] ) ) {
+			$url = add_query_arg( 'file', urlencode( $args['file'] ), $url );
+		}
+
+		$post_meta_key = '_gist_embed_' . md5( $url );
+		$transient_key = 'gist_embed_' . $this->shortcode_hash( 'gist', $args );
+
+		$html = get_transient( $transient_key );
+
+		// Retrieve html from Gist JSON endpoint.
+		if ( empty( $html ) ) {
+			$this->debug_log( '<strong>' . __( 'Doing remote request:', 'blazersix-gist-oembed' ) . '</strong> ' . $url, $this->shortcode_hash( 'gist', $args ) );
+			$json = $this->fetch_gist( $url );
+
+			if ( ! empty( $json->div ) ) {
+				$html = $json->div;
+			}
+
+			// Update the style sheet reference.
+			if ( ! empty( $json->stylesheet ) ) {
+				update_option( 'blazersix_gist_embed_stylesheet', $json->stylesheet );
+			}
+
+			// Failures are cached, too. Update the post to attempt to fetch again.
+			$html = ( $html ) ? $html : '{{unknown}}';
+			$transient_expire = 60 * 60 * 24;
+
+			if ( '{{unknown}}' != $html ) {
+				// Update the post meta fallback.
+				// @link http://core.trac.wordpress.org/ticket/21767
+				update_post_meta( $post->ID, $post_meta_key, addslashes( $html ) );
+				$html = $this->process_gist_html( $html, $args );
+				$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Remote Request', 'blazersix-gist-oembed' ) . '</p>', $this->shortcode_hash( 'gist', $args ) );
+			} elseif ( $fallback = get_post_meta( $post->ID, $post_meta_key, true ) ) {
+				// Return the fallback instead of {{unknown}}
+				$html = $this->process_gist_html( $fallback, $args );
+
+				// Cache the fallback for an hour.
+				$transient_expire = 60 * 60;
+				$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Post Meta Fallback', 'blazersix-gist-oembed' ) . '</p>', $this->shortcode_hash( 'gist', $args ) );
+			} else {
+				$this->debug_log( '<strong style="color: #e00">' . __( 'Remote call and transient failed and fallback was empty.', 'blazersix-gist-oembed' ) . '</strong>', $this->shortcode_hash( 'gist', $args ) );
+			}
+
+			// Cache the processed HTML.
+			set_transient( $transient_key, $html, $transient_expire );
+		} else {
+			$this->debug_log( '<p class="source">' . __( '<strong>Output Source:</strong> Transient Cache', 'blazersix-gist-oembed' ) . '</p>', $this->shortcode_hash( 'gist', $args ) );
+		}
+
+		$this->debug_log( '<strong>' . __( 'JSON Endpoint:', 'blazersix-gist-oembed' ) . '</strong> ' . $url, $this->shortcode_hash( 'gist', $args ) );
+		$this->debug_log( '<strong>' . __( 'Post Meta Cache Key:', 'blazersix-gist-oembed' ) . '</strong> ' . $post_meta_key, $this->shortcode_hash( 'gist', $args ) );
+		$this->debug_log( '<strong>' . __( 'Transient Key:', 'blazersix-gist-oembed' ) . '</strong> ' . $transient_key, $this->shortcode_hash( 'gist', $args ) );
+
+		return $html;
+	}
+
+	/**
+	 * Fetch Gist data from its JSON endpoint.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $url Gist JSON endpoint.
+	 *
+	 * @return object|bool Gist JSON object or false.
+	 */
+	public function fetch_gist( $url ) {
+		$response = wp_remote_get( $url, array( 'sslverify' => false ) );
+
+		if ( 200 == wp_remote_retrieve_response_code( $response ) ) {
+			return json_decode( wp_remote_retrieve_body( $response ) );
+		}
+
+		return false;
+	}
+
+	/**
+	 * Process the HTML returned from a Gist's JSON endpoint based on settings
+	 * passed through the shortcode.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $html HTML from the Gist's JSON endpoint.
+	 * @param array  $args List of shortcode attributes.
+	 *
+	 * @return string Modified HTML.
+	 */
+	public function process_gist_html( $html, $args ) {
+		// Remove the line number cell if it has been disabled.
+		if ( ! $args['show_line_numbers'] ) {
+			$html = preg_replace( '#<td class="line_numbers">.*?</td>#s', '', $html );
+		}
+
+		// Remove the meta section if it has been disabled.
+		if ( ! $args['show_meta'] ) {
+			$html = preg_replace( '#<div class="gist-meta">.*?</div>#s', '', $html );
+		}
+
+		$lines_pattern = '#(<td class="line_data"[^>]+>)(.+?)</td>#s';
+		preg_match( $lines_pattern, $html, $lines_matches );
+
+		if ( ! empty( $lines_matches[2] ) ) {
+			// Restrict the line number display if a range has been specified.
+			if ( $args['show_line_numbers'] && $args['lines']['min'] && $args['lines']['max'] ) {
+				$html = $this->limit_gist_line_numbers( $html, $args['lines'] );
+			}
+
+			if ( ! empty( $args['highlight'] ) ) {
+				// Flip to use isset() when looping through the lines.
+				$highlight = array_flip( $args['highlight'] );
+			}
+
+			// Extract and cleanup the individual lines from the Gist HTML into an array for processing.
+			$lines = trim( $lines_matches[2] );
+			$lines = preg_split( '#</pre>[\s]*<pre>#', substr( $lines, 5, strlen( $lines ) - 6 ) );
+
+			foreach ( $lines as $key => $line ) {
+				// Remove lines if they're not in the specified range and continue.
+				if ( ( $args['lines']['min'] && $key < $args['lines']['min'] - 1 ) || ( $args['lines']['max'] && $key > $args['lines']['max'] - 1 ) ) {
+					unset( $lines[ $key ] );
+					continue;
+				}
+
+				// Add classes for styling.
+				$classes = array( 'pre-line' );
+				$classes[] = ( $key % 2 ) ? 'pre-line-odd' : 'pre-line-even';
+				$style = '';
+
+				if ( isset( $highlight[ $key + 1 ] ) ) {
+					$classes[] = 'pre-line-highlight';
+
+					if ( ! empty( $args['highlight_color'] ) ) {
+						$style = ' style="background-color: ' . $args['highlight_color'] . ' !important"';
+					}
+				}
+
+				$prepend = '<pre class="' . join( ' ', $classes ) . '"' . $style . '>';
+
+				$lines[ $key ] = $prepend . $line . '</pre>';
+			}
+
+			$replacement = $lines_matches[1] . join( "\n", $lines ) . '</td>';
+			$html = preg_replace( $lines_pattern, $replacement, $html, 1 );
+		}
+
+		return $html;
+	}
+
+	/**
+	 * Removes line numbers from the Gist's HTML that fall outside the
+	 * supplied range.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $html  HTML from the Gist's JSON endpoint.
+	 * @param array  $range Array of min and max values.
+	 *
+	 * @return string Modified HTML.
+	 */
+	public function limit_gist_line_numbers( $html, $range ) {
+		// Limit the line numbers that should show.
+		$line_num_pattern = '#(<td class="line_numbers">)(.*?)</td>#s';
+
+		preg_match( $line_num_pattern, $html, $line_num_matches );
+
+		if ( $line_num_matches[2] ) {
+			$line_numbers = array_slice( explode( "\n", trim( $line_num_matches[2] ) ), $range['min'] - 1, $range['max'] - $range['min'] + 1 );
+
+			$replacement = $line_num_matches[1] . join( "\n", $line_numbers ) . '</td>';
+			$html = preg_replace( $line_num_pattern, $replacement, $html, 1 );
+		}
+
+		return $html;
+	}
+
+	/**
+	 * Removes transients associated with Gists embedded in a post.
+	 *
+	 * Retrieves the keys of meta data associated with a post and deletes any
+	 * transients with a matching embed key.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param int     $post_id     Post ID.
+	 * @param WP_Post $post_after  Post object after update.
+	 * @param WP_Post $post_before Post object before update.
+	 */
+	public function expire_gist_transients( $post_id, $post_after, $post_before ) {
+		$this->expire_transients = true;
+
+		// Run the shortcodes to clear associated transients.
+		do_shortcode( $post_after->post_content );
+		do_shortcode( $post_before->post_content );
+	}
+
+	/**
+	 * Expire the transient associated with a particular shortcode so its HTML
+	 * will be regenerated the next time it is requested.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param array $args List of shortcode attributes.
+	 */
+	public function expire_gist_transient( $args ) {
+		$key = 'gist_embed_' . $this->shortcode_hash( 'gist', $args );
+		set_transient( $key, null, -1 );
+	}
+
+	/**
+	 * Wrapper for a PSR-3 compatible logger.
+	 *
+	 * If no logger has been set via the set_logger() method on an instance of
+	 * this class, or WP_DEBUG is not enabled, then log messages quietly die
+	 * here.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @param string $message A message to log for the current shortcode.
+	 * @param mixed  $id      An ID under which the message should be grouped.
+	 */
+	protected function debug_log( $message, $id = null ) {
+		if ( defined( 'WP_DEBUG' ) && WP_DEBUG && isset( $this->logger ) ) {
+			$this->logger->debug( $message, array('key' => $id ) );
+		}
+	}
+
+	/**
+	 * Sort a shortcode's attributes by name and hash it for use as a cache
+	 * key and logger message grouping.
+	 *
+	 * @since 1.1.0
+	 */
+	protected function shortcode_hash( $tag, $args ) {
+		ksort( $args );
+		return md5( $tag . '_' . serialize( $args ) );
+	}
+}