<?php

App::uses('AppHelper','View/Helper');

App::import(array('Security', 'Validation'));

/**
 * CakePHP Gravatar Helper
 *
 * A CakePHP View Helper for the display of Gravatar images (http://www.gravatar.com)
 *
 * @copyright Copyright 2010, Graham Weldon
 * @license http://www.opensource.org/licenses/mit-license.php The MIT License
 * @package goodies
 * @subpackage goodies.tests.cases.helpers
 *
 */
class GravatarHelper extends AppHelper {

/**
 * Gravatar avatar image base URL
 *
 * @var string
 * @access private
 */
    private $__url = array(
        'http' => 'http://www.gravatar.com/avatar/',
        'https' => 'https://secure.gravatar.com/avatar/'
    );

/**
 * Hash type to use for email addresses
 *
 * @var string
 * @access private
 */
    private $__hashType = 'md5';

/**
 * Collection of allowed ratings
 *
 * @var array
 * @access private
 */
    private $__allowedRatings = array('g', 'pg', 'r', 'x');

/**
 * Default Icon sets
 *
 * @var array
 * @access private
 */
    private $__defaultIcons = array('none', 'identicon', 'mm', 'monsterid', 'wavatar', '404');

/**
 * Default settings
 *
 * @var array
 * @access private
 */
    private $__default = array(
        'default' => null,
        'size' => null,
        'rating' => null,
        'ext' => false);

/**
 * Helpers used by this helper
 *
 * @var array
 * @access public
 */
    public $helpers = array('Html');

/**
 * Constructor
 *
 * @access public
 */
    public function __construct() {
        // Default the secure option to match the current URL.
        $this->__default['secure'] = env('HTTPS');
    }

/**
 * Show gravatar for the supplied email address
 *
 * @param string $email Email address
 * @param array $options Array of options, keyed from default settings
 * @return string Gravatar image string
 * @access public
 */
    public function image($email, $options = array()) {
        $imageUrl = $this->url($email, $options);
        unset($options['default'], $options['size'], $options['rating'], $options['ext']);

        return $this->Html->image($imageUrl, $options);
    }

/**
 * Generate image URL
 *
 * @param string $email Email address
 * @param string $options Array of options, keyed from default settings
 * @return string Gravatar Image URL
 * @access public
 */
    public function url($email, $options = array()) {
        $options = $this->__cleanOptions(array_merge($this->__default, $options));
        $ext = $options['ext'];
        $secure = $options['secure'];
        unset($options['ext'], $options['secure']);
        $protocol = $secure === true ? 'https' : 'http';

        $imageUrl = $this->__url[$protocol] . $this->__emailHash($email, $this->__hashType);
        if ($ext === true) {
            // If 'ext' option is supplied and true, append an extension to the generated image URL.
            // This helps systems that don't display images unless they have a specific image extension on the URL.
            $imageUrl .= '.jpg';
        }
        $imageUrl .= $this->__buildOptions($options);
        return $imageUrl;
    }

/**
 * Sanitize the options array
 *
 * @param array $options Array of options, keyed from default settings
 * @return array Clean options array
 * @access private
 */
    private function __cleanOptions($options) {
        if (!isset($options['size']) || empty($options['size']) || !is_numeric($options['size'])) {
            unset($options['size']);
        } else {
            $options['size'] = min(max($options['size'], 1), 512);
        }

        if (!$options['rating'] || !in_array(mb_strtolower($options['rating']), $this->__allowedRatings)) {
            unset($options['rating']);
        }

        if (!$options['default']) {
            unset($options['default']);
        } else {
            if (!in_array($options['default'], $this->__defaultIcons) && !Validation::url($options['default'])) {
                unset($options['default']);
            }
        }
        return $options;
    }

/**
 * Generate email address hash
 *
 * @param string $email Email address
 * @param string $type Hash type to employ
 * @return string Email address hash
 * @access private
 */
    private function __emailHash($email, $type) {
        return Security::hash(mb_strtolower($email), $type);
    }

/**
 * Build Options URL string
 *
 * @param array $options Array of options, keyed from default settings
 * @return string URL string of options
 * @access private
 */
    private function __buildOptions($options = array()) {
        $gravatarOptions = array_intersect(array_keys($options), array_keys($this->__default));
        if (!empty($gravatarOptions)) {
            $optionArray = array();
            foreach ($gravatarOptions as $key) {
                $value = $options[$key];
                $optionArray[] = $key . '=' . mb_strtolower($value);
            }
            return '?' . implode('&amp;', $optionArray);
        }
        return '';
    }
}
?>