From f7e665c42f3f4678cce512416eeca6f032146fe1 Mon Sep 17 00:00:00 2001
From: Max Kostikov <max@kostikov.co>
Date: Sat, 12 Oct 2019 19:03:21 +0200
Subject: Add Opengraph function

---
 include/opengraph.php | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 include/opengraph.php

(limited to 'include/opengraph.php')

diff --git a/include/opengraph.php b/include/opengraph.php
new file mode 100644
index 000000000..b177673ac
--- /dev/null
+++ b/include/opengraph.php
@@ -0,0 +1,68 @@
+<?php
+/**
+ * @file include/opengraph.php
+ * @brief Add Opengraph metadata and related functions.
+ */
+ 
+ 
+ /**
+ * @brief Adds Opengraph meta tags into HTML head
+ *
+ * @param array $item
+ * @param array $profile
+ *
+ */
+ 
+ function opengraph_add_meta($item, $profile) {
+
+	if(! empty($item)) {
+
+		if(! empty($item['title']))
+			$ogtitle = $item['title'];
+
+		// find first image if exist
+		if(preg_match("/\[[zi]mg(=[0-9]+x[0-9]+)?\]([^\[]+)/is", $item['body'], $matches))
+			$ogimage = $matches[2];
+
+		// use summary as description if exist
+		$ogdesc = (empty($item['summary']) ? $item['body'] : $item['summary'] );
+		
+		$ogdesc = str_replace("#^[", "[", $ogdesc);
+	
+		$ogdesc = bbcode($ogdesc, [ 'tryoembed' => false ]);
+		$ogdesc = trim(html2plain($ogdesc, 0, true));
+		$ogdesc = html_entity_decode($ogdesc, ENT_QUOTES, 'UTF-8');
+		
+		// remove all URLs
+		$ogdesc = preg_replace("/https?\:\/\/[a-zA-Z0-9\:\/\-\?\&\;\.\=\_\~\#\%\$\!\+\,\@]+/", "", $ogdesc);
+		
+		// shorten description
+		$ogdesc = substr($ogdesc, 0, 300);
+		$ogdesc = str_replace("\n", " ", $ogdesc);
+		while (strpos($ogdesc, "  ") !== false)
+			$ogdesc = str_replace("  ", " ", $ogdesc);
+		if (substr($ogdesc, -1) != "\n")
+			$ogdesc = rtrim(substr($ogdesc, 0, strrpos($ogdesc, " ")), "?.,:;!-") . "...";
+		
+		$ogtype = "article";
+	}
+
+	$channel = channelx_by_n($profile['profile_uid']);
+
+	if(! isset($ogdesc)) {
+		if($profile['about'] && perm_is_allowed($channel['channel_id'],get_observer_hash(),'view_profile')) {
+			$ogdesc = $profile['about'];
+		}
+		else {
+			$ogdesc = sprintf( t('This is the home page of %s.'), $channel['channel_name']);
+		}
+	}
+
+	App::$page['htmlhead'] .= '<meta property="og:title" content="' . htmlspecialchars((isset($ogtitle) ? $ogtitle : $channel['channel_name'])) . '">' . "\r\n";
+	App::$page['htmlhead'] .= '<meta property="og:image" content="' . (isset($ogimage) ? $ogimage : $channel['xchan_photo_l']) . '">' . "\r\n";
+	App::$page['htmlhead'] .= '<meta property="og:description" content="' . htmlspecialchars($ogdesc) . '">' . 	"\r\n";
+	App::$page['htmlhead'] .= '<meta property="og:type" content="' . (isset($ogtype) ? $ogtype : "profile") . '">' . "\r\n";
+
+	return true;
+ }
+ 
\ No newline at end of file
-- 
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