Add support for 'subject' argument in safe-email shortcode. (#113)

* Add support for 'subject' argument in safe-email shortcode.

* safe-email: Add 'subject' argument to nextgen editor attributes.

* Update README for safe-email 'subject' option.

Author: woutgg

README.md

@@ -241,10 +241,10 @@ Do not process the shortcodes between these raw shortcode tags
 
 #### Safe-Email
 
-Encode an email address so that it's not so easily 'scrapable' by nefarious scripts.  This one has a couple of options: `autolink` toggle to turn the email into a link, and an `icon` option that lets you pick a font-awesome icon to prefix the email.  Both settings are optional.
+Encode an email address so that it's not so easily 'scrapable' by nefarious scripts.  This one has a couple of options: `autolink` toggle to turn the email into a link, an `icon` option that lets you pick a font-awesome icon to prefix the email, and a `subject` option that let's you specify the subject line for the user's mail agent to prefill.  All settings are optional.
 
 ```
-Safe-Email Address: [safe-email autolink="true" icon="envelope-o"]user@domain.com[/safe-email]
+Safe-Email Address: [safe-email autolink="true" icon="envelope-o" subject="Feedback"]user@domain.com[/safe-email]
 ```
 
 #### Section

classes/shortcodes/SafeEmailShortcode.php

@@ -14,23 +14,28 @@ public function init()
             }
 
             // Get shortcode content and parameters
-            $str = $sc->getContent();
+            $addr_str = $sc->getContent();
             $icon = $sc->getParameter('icon', false);
             $icon_base = "fa fa-";
             $autolink = $sc->getParameter('autolink', false);
+            $subject = $sc->getParameter('subject', false);
 
-            // Encode email
-            $email = '';
-            $str_len = strlen($str);
-            for ($i = 0; $i < $str_len; $i++) {
-                $email .= '&#' . ord($str[$i]). ';';
+            // Add subject, if any, to the link target.
+            $link_str = $addr_str;
+            if ($subject) {
+              $subject = html_entity_decode($subject);
+              $link_str .= '?subject=' . rawurlencode($subject);
             }
 
+            // Encode display text and link target
+            $email_disp = static::encodeText($addr_str);
+            $email_link = static::encodeText($link_str);
+
             // Handle autolinking
             if ($autolink) {
-                $output = '<a href="mailto:' . $email . '">' . $email . '</a>';
+                $output = '<a href="mailto:' . $email_link . '">' . $email_disp . '</a>';
             } else {
-                $output = $email;
+                $output = $email_disp;
             }
 
             // Handle icon option
@@ -48,4 +53,21 @@ public function init()
             return $output;
         });
     }
-}
+
+    /**
+     * encodes text as numeric HTML entities
+     * @param string $text the text to encode
+     * @return string the encoded text
+     */
+    private static function encodeText($text)
+    {
+      $encoded = '';
+      $str_len = strlen($text);
+
+      for ($i = 0; $i < $str_len; $i++) {
+        $encoded .= '&#' . ord($text[$i]). ';';
+      }
+
+      return $encoded;
+    }
+}

nextgen-editor/shortcodes/safe-email/safe-email.js

@@ -8,6 +8,12 @@ window.nextgenEditor.addShortcode('safe-email', {
     icon: '<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M19 9.25a4.924 4.924 0 011.666.291.25.25 0 00.334-.236V1.75a.158.158 0 00-.1-.147.16.16 0 00-.173.034L12.2 10.164a2.407 2.407 0 01-3.4 0L.271 1.637A.159.159 0 000 1.75v10.5A1.749 1.749 0 001.75 14h12.043a.25.25 0 00.249-.226A4.992 4.992 0 0119 9.25z"/><path d="M9.726 9.236a1.094 1.094 0 001.547 0L19.748.761A.437.437 0 0019.5.019 1.62 1.62 0 0019.249 0h-17.5A1.62 1.62 0 001.5.019a.437.437 0 00-.352.3.441.441 0 00.102.442zM22.5 15.5v-1.25a3.5 3.5 0 00-7 0v1.25A1.5 1.5 0 0014 17v5.5a1.5 1.5 0 001.5 1.5h7a1.5 1.5 0 001.5-1.5V17a1.5 1.5 0 00-1.5-1.5zM19 12.75a1.5 1.5 0 011.5 1.5v1.25h-3v-1.25a1.5 1.5 0 011.5-1.5zm1 7.5a1 1 0 11-1-1 1 1 0 011 1z"/></svg>',
   },
   attributes: {
+    subject: {
+      type: String,
+      title: 'Subject',
+      widget: 'input-text',
+      default: '',
+    },
     icon: {
       type: String,
       title: 'Icon',