CodeIgniter Rating Library + Microdata (optional)

codeigniter-rating-lib.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**
 * Rating Library
 * Using jQuery Raty plugin to rate products
 * @author Nikola Katsarov 
 * @website http://katsarov.biz
 */
 
class Rating {

    private $rating_table = 'product_ratings';
    public $seo = true;

    public function __construct()
    {
        $this->CI =& get_instance();
        if(!$this->CI->db->table_exists($this->rating_table)){
            $this->install();
        }
    }

    private function install()
    {
    	$sql = "CREATE TABLE IF NOT EXISTS `".$this->rating_table."` (
				  `id` int(11) NOT NULL AUTO_INCREMENT,
				  `product_id` int(11) NOT NULL,
				  `score` int(11) NOT NULL DEFAULT '1',
				  `date_registered` datetime NOT NULL,
				  `user_ip` varchar(50) DEFAULT NULL,
				  PRIMARY KEY (`id`),
				  KEY `product_id` (`product_id`)
				) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
				";
        $this->CI->db->query($sql);
    }

    public function get($product_id)
    {
    	$rating->avg = $this->get_avarage($product_id);
    	$rating->votes = $this->get_total_votes($product_id);
    	if(!$rating->avg){
    		$rating->avg = 0;
    	}
    	return $rating;
    }

    public function generate_html($product_id, $product_name='', $product_photo='', $seo=true)
    {
    	$this->seo = $seo;
    	if ($this->seo) {
    		$html= '<div id="product-rating" data-score="'.$this->get($product_id)->avg.'"></div>';
    		$html.= '<div itemscope itemtype="http://data-vocabulary.org/Review-aggregate">';
    		if($product_name){
    			$html.= '<meta itemprop="itemreviewed" content = "'.$product_name.'"> ';
    		}
    		if($product_photo){
    			$html.= '<meta itemprop="photo" content = "'.$product_photo.'"> ';
    		}
    		$html.='<span itemprop="rating" itemscope itemtype="http://data-vocabulary.org/Rating">';
	    		$html.='<meta itemprop="average" content = "'.$this->get($product_id)->avg.'">';
	    		$html.='<meta itemprop="best" content = "5">';
	    		$html.='<meta itemprop="votes" content = "'.$this->get($product_id)->votes.'">';
    		$html.='</span>';
    		$html.='</div>';
    	}else{
    		$html = '<div id="product-rating" data-score="'.$this->get($product_id)->avg.'"></div>';
    	}

    	return $html;
    }

    private function get_total_votes($product_id)
    {
    	$this->CI->db->where('product_id', $product_id);
    	return $this->CI->db->count_all_results($this->rating_table);
    }

    private function get_avarage($product_id)
    {
    	$this->CI->db->where('product_id', $product_id);
    	$this->CI->db->select_avg('score');
    	$q = $this->CI->db->get($this->rating_table);
    	return round($q->row()->score, 2);
    }

    public function add($data)
    {
    	$this->CI->db->set('date_registered', 'NOW()', false);
    	if($this->CI->db->insert($this->rating_table, $data)){
    		return true;
    	}
    }

    public function update($data)
    {
    	$this->CI->db->set('date_registered', 'NOW()', false);
    	if($this->CI->db->update($this->rating_table)){
    		return true;
    	}
    }

    public function delete($rating_id)
    {
    	$this->CI->db->where('id', $rating_id);
    	if($this->CI->db->delete($this->rating_table)){
    		return true;
    	}
    }


}