/system/libraries/Html.php

<?php
/**
 * This file is part of the Yet Another PHP Framework package.
 * (c) 2010 Adrian Videnie <{@link mailto:avidenie@gmail.com avidenie@gmail.com}>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 *
 * @package    Framework
 * @subpackage Helpers
 * @author     Adrian Videnie <avidenie@gmail.com>
 * @copyright  2010 Adrian Videnie
 * @license    http://www.opensource.org/licenses/mit-license.php The MIT license
 */

/**
 *
 * HTML helper class.
 *
 * @package    Framework
 * @subpackage Helpers
 * @author     Adrian Videnie <avidenie@gmail.com>
 * @copyright  2010 Adrian Videnie
 * @license    http://www.opensource.org/licenses/mit-license.php The MIT license
 */
class Html
{
    /**
     * Convert special characters to HTML entities
     *
     * @param  string  string to convert
     * @param  boolean encode existing entities
     * @return string
     */
    public static function escape($string, $doubleEncode = true)
    {
        return htmlspecialchars((string) $string, ENT_QUOTES, 'UTF-8', $doubleEncode);
    }

    /**
     * Compiles an array of HTML attributes into an attribute string.
     *
     * @param   string|array  array of attributes
     * @return  string
     */
    public static function attributes($attributes)
    {
        if (empty($attributes)) {
            return '';
        }

        if (is_string($attributes)) {
            return ' ' . trim($attributes);
        }

        $compiled = '';
        foreach ($attributes as $key => $value) {
            $compiled .= ' ' . $key . '="' . $value . '"';
        }

        return $compiled;
    }

    /**
     * Fix generated URIs.
     *
     * @param  string  URI string.
     * @param  mixed   Force absolute URI or force non-default protocol, eg.https.
     * @param  boolean Whether this is a public resource or not.
     * @return string  The fixed, transformed URI.
     */
    public static function href($uri, $absolute = false, $publicResource = false)
    {
        if (false === strpos($uri, '://')) {
            // Make sure the uri is in a proper form.
            $uri = '/' . ltrim($uri, '/');
            // The Request method to use to generate the Uri.
            $method = 'baseUri';
            // Change method and add the path to the public directory.
            if (true == $publicResource) {
                $method = 'basePath';
                $uri = Green::config('framework.public_path') . $uri;
            }
            $request = Request::instance();
            // Create the Uri.
            $uri = $request->$method() . $uri;
            if (false !== $absolute) {
                $uri = $request->hostname($absolute) . $uri;
            }
        }
        return $uri; 
    }

    /**
     * Generates an uri given the name of a route.
     *
     * @param  mixed $name The name of a Route to use. If null it will use the current Route.
     * @param  array $urlOptions Options passed to the assemble method of the Route object.
     * @param  boolean $absolute Whether or not to return an absolute URI.
     * @param  boolean $reset Whether or not to reset the route defaults with those provided.

     * @return string Url for the link href attribute.
     */
    public static function uri($name = null, array $urlOptions = array(), $absolute = false, $reset = true, $encode = true)
    {
        $router = Router::instance();
        $uri = $router->assemble($urlOptions, $name, $reset, $encode);

        return self::href($uri, $absolute);
    }

    /**
     * Generates an obfuscated version of an email address.
     *
     * @param  string E-mail address
     * @return string Obfuscated version of the e-mail address
     */
    public static function email($email)
    {
        $safe = '';
        foreach (str_split($email) as $letter) {
            switch (($letter === '@') ? rand(1, 2) : rand(1, 3)) {
                // HTML entity code
                case 1: $safe .= '&#'.ord($letter).';'; break;
                // Hex character code
                case 2: $safe .= '&#x'.dechex(ord($letter)).';'; break;
                // Raw (no) encoding
                case 3: $safe .= $letter;
            }
        }
        return $safe;
    }

    /**
     * Creates a image link.
     *
     * @param  string         Image source.
     * @param  string|array   Image alt attribute, or an array of attributes
     * @param  boolean|string Absolute uri, force non-default protocol, eg.https
     * @return string         The image link.
     */
    public static function image($src, $alt = null, $absolute = false)
    {
        // Create attribute list
        $attributes = array('src' => self::href($src, $absolute, true));
        
        if (is_array($alt)) {
            $attributes += $alt;
        } elseif (!empty($alt)) {
            // Add alt to attributes
            $attributes['alt'] = htmlspecialchars((string) $alt, ENT_QUOTES, 'UTF-8');
        }
        if (!isset($attributes['alt'])) {
            // Calculate a default alt.
            $attributes['alt'] = basename($attributes['src'], substr($attributes['src'], strrpos($attributes['src'], '.')));
        }

        return '<img' . self::attributes($attributes) . ' />';
    }

    /**
     * Creates an email anchor.
     *
     * @param  string E-mail address to send to
     * @param  string Link text
     * @param  array  HTML anchor attributes
     * @return string The e-mail anchor
     */
    public static function mailto($email, $title = null, $attributes = null)
    {
        // Remove the subject or other parameters that do not need to be encoded
        if (false !== strpos($email, '?')) {
            // Extract the parameters from the email address
            list ($email, $params) = explode('?', $email, 2);

            // Make the params into a query string, replacing spaces
            $params = '?' . str_replace(' ', '%20', $params);
        } else {
            // No parameters
            $params = '';
        }

        // Obfuscate email address
        $safe = self::email($email);

        // Title defaults to the encoded email address
        if (empty($title)) {
            $title = $safe;
        } else {
            $title = htmlspecialchars((string) $title, ENT_QUOTES, 'UTF-8');
        }

        // Parse attributes
        if (!empty($attributes)) {
            $attributes = self::attributes($attributes);
        }

        // Encoded start of the href="" is a static encoded version of 'mailto:'
        return '<a href="&#109;&#097;&#105;&#108;&#116;&#111;&#058;' . $safe . $params . '"' . $attributes . '>' . $title . '</a>';
    }
  
    /**
     * Returns a <script></script> tag.
     * 
     * @param  string The source href for the script.
     * @param  array  Additional attributes for the <script> tag.
     * @param  mixed  Whether to force absolute URI or a non-default protocol, eg.https.
     * @return string The <script></script> tag.
     */
    public static function script($src, array $attributes = array(), $absolute = false)
    {       
        // Create a proper relative or absolute URI, as requested.
        $attributes['src'] = self::href($src, $absolute, true);
        
        if (isset($attributes['anti_cache'])) {
            $attributes['src'] .= '?' . date('U');
            unset($attributes['anti_cache']);
        }
        
        if (empty($attributes['type'])) {
            $attributes['type'] = 'text/javascript';
        }
        
        return '<script' . self::attributes($attributes) . '></script>';
    }

    /** 
     * Returns a <script></script> block that properly commented for inclusion
     * in XHTML documents.
     * 
     * @see    http://developer.mozilla.org/en/docs/Properly_Using_CSS_and_JavaScript_in_XHTML_Documents 
     * @param  string The source of the script.
     * @param  array  Additional attributes for the <script> tag.
     * @return string The <script></script> tag with the inline script.
     */
	public static function inlineScript($code, array $attributes = array())
    {
        // Make sure we don't accidentally write a source script href.
        unset($attributes['src']);
        
        if (empty($attributes['type'])) {
            $attributes['type'] = 'text/javascript';
        }
        
        return '<script'
             . self::attributes($attributes) . ">\n"
             . "//<![CDATA[\n"
             . trim($code)
             . "\n//]]>\n"
             . "</script>\n";
    }

    /**
     * Returns a <link>...</link> tag for external stylesheets.
     * 
     * Adds "media" attribute if not specified, and always uses "type" attribute
     * of "text/css".
     * 
     * @param  string         The source href for the stylesheet.
     * @param  array          Additional attributes for the <style> tag.
     * @param  boolean|string Absolute uri, force non-default protocol, eg.https
     * @return string         The <link>...</link> tag.
     * 
     */
    public static function style($href, array $attributes = array(), $absolute = false)
    {
        // Build the URI as an href to a public resource.
        $attributes['href'] = self::href($href, $absolute, true);
        
        // Force type="text/css" and rel="stylesheet".
        $attributes['type'] = 'text/css';
        $attributes['rel'] = 'stylesheet';
        
        // Default to media="screen".
        if (empty($attributes['media'])) {
            $attributes['media'] = 'screen';
        }
               
        // Build and return the tag.
        return '<link' . self::attributes($attributes) . ' />';
    }
} // End Html class.