From 1ad282df0f06ef489d39fd20e602d9b441eb0eca Mon Sep 17 00:00:00 2001
From: Denny Dai <i@daihan.cn>
Date: Thu, 31 Mar 2016 22:46:57 -0500
Subject: [PATCH] add Plugin.php

---
 plugin.php | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 plugin.php
diff --git a/plugin.php b/plugin.php
new file mode 100644
index 0000000..a79e8e2
--- /dev/null
+++ b/plugin.php
@@ -0,0 +1,59 @@
+<?php
+/*
+Plugin Name: Preview URL with QR Code
+Plugin URI: https://github.com/dennydai
+Description: Preview URLs before you're redirected there
+Version: 1.0
+Author: Denny Dai
+Author URI: https://dennydai.github.io
+*/
+
+// EDIT THIS
+
+// Character to add to a short URL to trigger the preview interruption
+define( 'OZH_PREVIEW_CHAR', '~' );
+
+// DO NO EDIT FURTHER
+
+// Handle failed loader request and check if there's a ~
+yourls_add_action( 'loader_failed', 'ozh_preview_loader_failed' );
+function ozh_preview_loader_failed( $args ) {
+        $request = $args[0];
+        $pattern = yourls_make_regexp_pattern( yourls_get_shorturl_charset() );
+        if( preg_match( "@^([$pattern]+)".OZH_PREVIEW_CHAR."$@", $request, $matches ) ) {
+                $keyword   = isset( $matches[1] ) ? $matches[1] : '';
+                $keyword = yourls_sanitize_keyword( $keyword );
+                ozh_preview_show( $keyword );
+                die();
+        }
+}
+
+// Show the preview screen for a short URL
+function ozh_preview_show( $keyword ) {
+        require_once( YOURLS_INC.'/functions-html.php' );
+
+        yourls_html_head( 'preview', 'Short URL preview' );
+        yourls_html_logo();
+
+        $title = yourls_get_keyword_title( $keyword );
+        $url   = yourls_get_keyword_longurl( $keyword );
+        $base  = YOURLS_SITE;
+        $char  = OZH_PREVIEW_CHAR;
+        $qrcode = 'data:image/png;base64,'.base64_encode(file_get_contents('http://chart.apis.google.com/chart?chs=200x200&cht=qr&chld=M&chl='.YOURLS_SITE.'/'.$keyword));
+
+        echo <<<HTML
+        <h2>Link Preview</h2>
+        <p>You requested the short URL <strong><a href="$base/$keyword">$base/$keyword</a></strong></p>
+        <p>This short URL points to:</p>
+        <ul>
+        <li>Long URL: <strong><a href="$base/$keyword">$url</a></strong></li>
+        <li>Page title: <strong>$title</strong></li>
+        <li>QR Code: <br><img src="$qrcode"></li>
+        </ul>
+        <p>If you still want to visit this link, please <strong><a href="$base/$keyword">click here</a></strong>.</p>
+
+        <p>Thank you for using our shortening service.</p>
+HTML;
+
+        yourls_html_footer();
+}
\ No newline at end of file
