From 03f6da019d3c2d954eaa28a5410e9814bad939ae Mon Sep 17 00:00:00 2001
From: Matthias Pfefferle <pfefferle@gmail.com>
Date: Tue, 22 Jan 2019 20:51:22 +0100
Subject: [PATCH] basic hashtag support

see #21 #20
---
 README.md                              |  6 ++-
 activitypub.php                        |  6 +++
 includes/class-activitypub-hashtag.php | 51 ++++++++++++++++++++++++++
 languages/activitypub.pot              |  2 +-
 readme.txt                             |  6 ++-
 5 files changed, 68 insertions(+), 3 deletions(-)
 create mode 100644 includes/class-activitypub-hashtag.php

diff --git a/README.md b/README.md
index dce067a..a189385 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 **Donate link:** https://notiz.blog/donate/  
 **Tags:** OStatus, fediverse, activitypub, activitystream  
 **Requires at least:** 4.7  
-**Tested up to:** 5.0.2  
+**Tested up to:** 5.0.3  
 **Stable tag:** 0.2.1  
 **Requires PHP:** 5.6  
 **License:** MIT  
@@ -55,6 +55,10 @@ To implement:
 
 Project maintained on github at [pfefferle/wordpress-activitypub](https://github.com/pfefferle/wordpress-activitypub).
 
+### 0.3.0 ###
+
+* basic hashtag support
+
 ### 0.2.1 ###
 
 * customizable backlink (permalink or shorturl)
diff --git a/activitypub.php b/activitypub.php
index 2845a26..4841a13 100644
--- a/activitypub.php
+++ b/activitypub.php
@@ -16,6 +16,8 @@
  * Initialize plugin
  */
 function activitypub_init() {
+	defined( 'ACTIVITYPUB_HASHTAGS_REGEXP' ) || define( 'ACTIVITYPUB_HASHTAGS_REGEXP', '(^|\s|>)#([^\s<>]+)\b' );
+
 	require_once dirname( __FILE__ ) . '/includes/class-activitypub-signature.php';
 	require_once dirname( __FILE__ ) . '/includes/class-activitypub-post.php';
 	require_once dirname( __FILE__ ) . '/includes/class-activitypub-activity.php';
@@ -65,6 +67,10 @@ function activitypub_init() {
 	add_action( 'admin_menu', array( 'Activitypub_Admin', 'admin_menu' ) );
 	add_action( 'admin_init', array( 'Activitypub_Admin', 'register_settings' ) );
 	add_action( 'show_user_profile', array( 'Activitypub_Admin', 'add_fediverse_profile' ) );
+
+	require_once dirname( __FILE__ ) . '/includes/class-activitypub-hashtag.php';
+	add_filter( 'wp_insert_post', array( 'Activitypub_Hashtag', 'insert_post' ), 99, 2 );
+	add_filter( 'the_content', array( 'Activitypub_Hashtag', 'the_content' ), 99, 2 );
 }
 add_action( 'plugins_loaded', 'activitypub_init' );
 
diff --git a/includes/class-activitypub-hashtag.php b/includes/class-activitypub-hashtag.php
new file mode 100644
index 0000000..efa3c2b
--- /dev/null
+++ b/includes/class-activitypub-hashtag.php
@@ -0,0 +1,51 @@
+<?php
+/**
+ * ActivityPub Hashtag Class
+ */
+class Activitypub_Hashtag {
+	/**
+	 * Filter to save #tags as real WordPress tags
+	 *
+	 * @param int $id the rev-id
+	 * @param array $data the post-data as array
+	 */
+	public static function insert_post( $id, $data ) {
+		if ( preg_match_all( '/' . ACTIVITYPUB_HASHTAGS_REGEXP . '/i', $data->post_content, $match ) ) {
+			$tags = implode( ', ', $match[2] );
+
+			wp_add_post_tags( $data->post_parent, $tags );
+		}
+
+		return $id;
+	}
+
+	/**
+	 * Filter to replace the #tags in the content with links
+	 *
+	 * @param string $the_content the post-content
+	 */
+	public static function the_content( $the_content ) {
+		$the_content = preg_replace_callback( '/' . ACTIVITYPUB_HASHTAGS_REGEXP . '/i', array( 'Activitypub_Hashtag', 'replace_with_links' ), $the_content );
+
+		return $the_content;
+	}
+
+	/**
+	 * A callback for preg_replace to build the term links
+	 *
+	 * @param array $result the preg_match results
+	 * @return string the final string
+	 */
+	public static function replace_with_links( $result ) {
+		$tag = $result[2];
+		$space = $result[1];
+		$tag_object = get_term_by( 'name', $result[2], 'post_tag' );
+
+		if ( $tag_object ) {
+			$link = get_term_link( $tag_object, 'post_tag' );
+			return "$space<a href='$link' rel='tag'>#$tag</a>";
+		}
+
+		return $space . '#' . $tag;
+	}
+}
diff --git a/languages/activitypub.pot b/languages/activitypub.pot
index 6712783..2602354 100644
--- a/languages/activitypub.pot
+++ b/languages/activitypub.pot
@@ -4,7 +4,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: ActivityPub 0.2.1\n"
 "Report-Msgid-Bugs-To: https://wordpress.org/support/plugin/activitypub\n"
-"POT-Creation-Date: 2019-01-16 20:52:51+00:00\n"
+"POT-Creation-Date: 2019-01-22 19:51:00+00:00\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=utf-8\n"
 "Content-Transfer-Encoding: 8bit\n"
diff --git a/readme.txt b/readme.txt
index bc842f2..4c8dc87 100644
--- a/readme.txt
+++ b/readme.txt
@@ -3,7 +3,7 @@ Contributors: pfefferle
 Donate link: https://notiz.blog/donate/
 Tags: OStatus, fediverse, activitypub, activitystream
 Requires at least: 4.7
-Tested up to: 5.0.2
+Tested up to: 5.0.3
 Stable tag: 0.2.1
 Requires PHP: 5.6
 License: MIT
@@ -55,6 +55,10 @@ To implement:
 
 Project maintained on github at [pfefferle/wordpress-activitypub](https://github.com/pfefferle/wordpress-activitypub).
 
+= 0.3.0 =
+
+* basic hashtag support
+
 = 0.2.1 =
 
 * customizable backlink (permalink or shorturl)