From d7e1ce47bbc51f3f0b2fac6ce17b83378f5393b1 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 02:44:43 -0500
Subject: [PATCH 01/18] Use item.thr-parent as expected in Model\Item::insert()

- Rework Model\Item::getTopLevelParent
- Backward compatibility with item.parent-uri is ensured
---
 src/Model/Item.php | 175 ++++++++++++++++++++++-----------------------
 1 file changed, 85 insertions(+), 90 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index d5f57cff7..c03722372 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1379,7 +1379,7 @@ class Item
 	public static function isValid(array $item)
 	{
 		// When there is no content then we don't post it
-		if ($item['body'].$item['title'] == '') {
+		if ($item['body'] . $item['title'] == '') {
 			Logger::notice('No body, no title.');
 			return false;
 		}
@@ -1497,88 +1497,43 @@ class Item
 	}
 
 	/**
-	 * Fetch parent data for the given item array
+	 * Fetch top-level parent data for the given item array
 	 *
 	 * @param array $item
 	 * @return array item array with parent data
+	 * @throws \Exception
 	 */
-	private static function getParentData(array $item)
+	private static function getTopLevelParent(array $item)
 	{
-		// find the parent and snarf the item id and ACLs
-		// and anything else we need to inherit
-
-		$fields = ['uri', 'parent-uri', 'id', 'deleted',
+		$fields = ['uid', 'uri', 'parent-uri', 'id', 'deleted',
 			'allow_cid', 'allow_gid', 'deny_cid', 'deny_gid',
 			'wall', 'private', 'forum_mode', 'origin', 'author-id'];
-		$condition = ['uri' => $item['parent-uri'], 'uid' => $item['uid']];
+		$condition = ['uri' => $item['thr-parent'], 'uid' => $item['uid']];
 		$params = ['order' => ['id' => false]];
 		$parent = self::selectFirst($fields, $condition, $params);
 
 		if (!DBA::isResult($parent)) {
-			Logger::info('item parent was not found - ignoring item', ['parent-uri' => $item['parent-uri'], 'uid' => $item['uid']]);
+			Logger::info('item parent was not found - ignoring item', ['thr-parent' => $item['thr-parent'], 'uid' => $item['uid']]);
 			return [];
-		} else {
-			// is the new message multi-level threaded?
-			// even though we don't support it now, preserve the info
-			// and re-attach to the conversation parent.
-			if ($parent['uri'] != $parent['parent-uri']) {
-				$item['parent-uri'] = $parent['parent-uri'];
-
-				$condition = ['uri' => $item['parent-uri'],
-					'parent-uri' => $item['parent-uri'],
-					'uid' => $item['uid']];
-				$params = ['order' => ['id' => false]];
-				$toplevel_parent = self::selectFirst($fields, $condition, $params);
-
-				if (DBA::isResult($toplevel_parent)) {
-					$parent = $toplevel_parent;
-				}
-			}
-
-			$item['parent']        = $parent['id'];
-			$item["deleted"]       = $parent['deleted'];
-			$item["allow_cid"]     = $parent['allow_cid'];
-			$item['allow_gid']     = $parent['allow_gid'];
-			$item['deny_cid']      = $parent['deny_cid'];
-			$item['deny_gid']      = $parent['deny_gid'];
-			$item['parent_origin'] = $parent['origin'];
-
-			// Don't federate received participation messages
-			if ($item['verb'] != Activity::FOLLOW) {
-				$item['wall'] = $parent['wall'];
-			} else {
-				$item['wall'] = false;
-			}
-
-			/*
-			 * If the parent is private, force privacy for the entire conversation
-			 * This differs from the above settings as it subtly allows comments from
-			 * email correspondents to be private even if the overall thread is not.
-			 */
-			if ($parent['private']) {
-				$item['private'] = $parent['private'];
-			}
-
-			/*
-			 * Edge case. We host a public forum that was originally posted to privately.
-			 * The original author commented, but as this is a comment, the permissions
-			 * weren't fixed up so it will still show the comment as private unless we fix it here.
-			 */
-			if ((intval($parent['forum_mode']) == 1) && ($parent['private'] != self::PUBLIC)) {
-				$item['private'] = self::PUBLIC;
-			}
-
-			// If its a post that originated here then tag the thread as "mention"
-			if ($item['origin'] && $item['uid']) {
-				DBA::update('thread', ['mention' => true], ['iid' => $item['parent']]);
-				Logger::info('tagged thread as mention', ['parent' => $item['parent'], 'uid' => $item['uid']]);
-			}
-
-			// Update the contact relations
-			Contact\Relation::store($parent['author-id'], $item['author-id'], $item['created']);
 		}
 
-		return $item;
+		if ($parent['uri'] == $parent['parent-uri']) {
+			return $parent;
+		}
+
+		$condition = ['uri' => $item['parent-uri'],
+			'parent-uri' => $item['parent-uri'],
+			'uid' => $item['uid']];
+		// We select wall = 1 in priority for top level permission checks
+		$params = ['order' => ['wall' => true]];
+		$toplevel_parent = self::selectFirst($fields, $condition, $params);
+
+		if (!DBA::isResult($toplevel_parent)) {
+			Logger::info('item parent was not found - ignoring item', ['parent-uri' => $item['parent-uri'], 'uid' => $item['uid']]);
+			return [];
+		}
+
+		return $toplevel_parent;
 	}
 
 	/**
@@ -1636,13 +1591,14 @@ class Item
 		// Store URI data
 		$item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 
+		// Backward compatibility: parent-uri used to be the direct parent uri.
+		// If it is provided without a thr-parent, it probably is the old behavior.
+		$item['thr-parent'] = trim($item['thr-parent'] ?? $item['parent-uri'] ?? $item['uri']);
+		$item['parent-uri'] = $item['thr-parent'];
+
 		// Store conversation data
 		$item = Conversation::insert($item);
 
-		if (!empty($item['thr-parent'])) {
-			$item['parent-uri'] = $item['thr-parent'];
-		}
-
 		/*
 		 * Do we already have this item?
 		 * We have to check several networks since Friendica posts could be repeated
@@ -1740,6 +1696,62 @@ class Item
 			return 0;
 		}
 
+		if ($item['thr-parent'] != $item['uri']) {
+			$toplevel_parent = self::getTopLevelParent($item);
+			if (empty($toplevel_parent)) {
+				return 0;
+			}
+
+			$parent_id          = $toplevel_parent['id'];
+			$item['parent-uri'] = $toplevel_parent['uri'];
+			$item['deleted']    = $toplevel_parent['deleted'];
+			$item['allow_cid']  = $toplevel_parent['allow_cid'];
+			$item['allow_gid']  = $toplevel_parent['allow_gid'];
+			$item['deny_cid']   = $toplevel_parent['deny_cid'];
+			$item['deny_gid']   = $toplevel_parent['deny_gid'];
+			$parent_origin      = $toplevel_parent['origin'];
+
+			// Don't federate received participation messages
+			if ($item['verb'] != Activity::FOLLOW) {
+				$item['wall'] = $toplevel_parent['wall'];
+			} else {
+				$item['wall'] = false;
+			}
+
+			/*
+			 * If the parent is private, force privacy for the entire conversation
+			 * This differs from the above settings as it subtly allows comments from
+			 * email correspondents to be private even if the overall thread is not.
+			 */
+			if ($toplevel_parent['private']) {
+				$item['private'] = $toplevel_parent['private'];
+			}
+
+			/*
+			 * Edge case. We host a public forum that was originally posted to privately.
+			 * The original author commented, but as this is a comment, the permissions
+			 * weren't fixed up so it will still show the comment as private unless we fix it here.
+			 */
+			if ((intval($toplevel_parent['forum_mode']) == 1) && ($toplevel_parent['private'] != self::PUBLIC)) {
+				$item['private'] = self::PUBLIC;
+			}
+
+			// If its a post that originated here then tag the thread as "mention"
+			if ($item['origin'] && $item['uid']) {
+				DBA::update('thread', ['mention' => true], ['iid' => $parent_id]);
+				Logger::info('tagged thread as mention', ['parent' => $parent_id, 'uid' => $item['uid']]);
+			}
+
+			// Update the contact relations
+			Contact\Relation::store($toplevel_parent['author-id'], $item['author-id'], $item['created']);
+
+			unset($item['parent']);
+			unset($item['parent_origin']);
+		} else {
+			$parent_id = 0;
+			$parent_origin = $item['origin'];
+		}
+
 		// We don't store the causer link, only the id
 		unset($item['causer-link']);
 
@@ -1753,23 +1765,6 @@ class Item
 		unset($item['owner-name']);
 		unset($item['owner-avatar']);
 
-		$item['thr-parent'] = $item['parent-uri'];
-
-		if ($item['parent-uri'] != $item['uri']) {
-			$item = self::getParentData($item);
-			if (empty($item)) {
-				return 0;
-			}
-
-			$parent_id = $item['parent'];
-			unset($item['parent']);
-			$parent_origin = $item['parent_origin'];
-			unset($item['parent_origin']);
-		} else {
-			$parent_id = 0;
-			$parent_origin = $item['origin'];
-		}
-
 		$item['parent-uri-id'] = ItemURI::getIdByURI($item['parent-uri']);
 		$item['thr-parent-id'] = ItemURI::getIdByURI($item['thr-parent']);
 

From 0c3a5c815e7067aa587ac8f0bb8e32bb5892082e Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Mon, 9 Nov 2020 11:13:18 -0500
Subject: [PATCH 02/18] Remove obsolete references to item.parent-uri

---
 include/api.php             | 1 -
 mod/photos.php              | 3 ---
 src/Model/Event.php         | 1 -
 src/Model/Item.php          | 7 +++----
 src/Module/Contact/Poke.php | 1 -
 src/Worker/OnePoll.php      | 1 +
 6 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/include/api.php b/include/api.php
index 87ce982b0..5969ccd5f 100644
--- a/include/api.php
+++ b/include/api.php
@@ -4766,7 +4766,6 @@ function post_photo_item($hash, $allow_cid, $deny_cid, $allow_gid, $deny_gid, $f
 	$arr['guid']          = System::createUUID();
 	$arr['uid']           = intval(api_user());
 	$arr['uri']           = $uri;
-	$arr['parent-uri']    = $uri;
 	$arr['type']          = 'photo';
 	$arr['wall']          = 1;
 	$arr['resource-id']   = $hash;
diff --git a/mod/photos.php b/mod/photos.php
index bba12aace..e94a3ed8d 100644
--- a/mod/photos.php
+++ b/mod/photos.php
@@ -395,7 +395,6 @@ function photos_post(App $a)
 			$arr['guid']          = System::createUUID();
 			$arr['uid']           = $page_owner_uid;
 			$arr['uri']           = $uri;
-			$arr['parent-uri']    = $uri;
 			$arr['post-type']     = Item::PT_IMAGE;
 			$arr['wall']          = 1;
 			$arr['resource-id']   = $photo['resource-id'];
@@ -560,7 +559,6 @@ function photos_post(App $a)
 					$arr['guid']          = System::createUUID();
 					$arr['uid']           = $page_owner_uid;
 					$arr['uri']           = $uri;
-					$arr['parent-uri']    = $uri;
 					$arr['wall']          = 1;
 					$arr['contact-id']    = $owner_record['id'];
 					$arr['owner-name']    = $owner_record['name'];
@@ -791,7 +789,6 @@ function photos_post(App $a)
 	$arr['guid']          = System::createUUID();
 	$arr['uid']           = $page_owner_uid;
 	$arr['uri']           = $uri;
-	$arr['parent-uri']    = $uri;
 	$arr['type']          = 'photo';
 	$arr['wall']          = 1;
 	$arr['resource-id']   = $resource_id;
diff --git a/src/Model/Event.php b/src/Model/Event.php
index 6f8ed123c..5139abc43 100644
--- a/src/Model/Event.php
+++ b/src/Model/Event.php
@@ -347,7 +347,6 @@ class Event
 				$item_arr['uid']           = $event['uid'];
 				$item_arr['contact-id']    = $event['cid'];
 				$item_arr['uri']           = $event['uri'];
-				$item_arr['parent-uri']    = $event['uri'];
 				$item_arr['guid']          = $event['guid'];
 				$item_arr['plink']         = $arr['plink'] ?? '';
 				$item_arr['post-type']     = Item::PT_EVENT;
diff --git a/src/Model/Item.php b/src/Model/Item.php
index c03722372..e67b86234 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1633,7 +1633,6 @@ class Item
 		$item['coord']         = trim($item['coord'] ?? '');
 		$item['visible']       = (isset($item['visible']) ? intval($item['visible']) : 1);
 		$item['deleted']       = 0;
-		$item['parent-uri']    = trim(($item['parent-uri'] ?? '') ?: $item['uri']);
 		$item['post-type']     = ($item['post-type'] ?? '') ?: self::PT_ARTICLE;
 		$item['verb']          = trim($item['verb'] ?? '');
 		$item['object-type']   = trim($item['object-type'] ?? '');
@@ -2858,14 +2857,15 @@ class Item
 				unset($datarray["plink"]);
 				$datarray["uri"] = self::newURI($contact['uid'], $datarray["guid"]);
 				$datarray["uri-id"] = ItemURI::getIdByURI($datarray["uri"]);
-				$datarray["parent-uri"] = $datarray["uri"];
-				$datarray["thr-parent"] = $datarray["uri"];
 				$datarray["extid"] = Protocol::DFRN;
 				$urlpart = parse_url($datarray2['author-link']);
 				$datarray["app"] = $urlpart["host"];
 				if (!empty($old_uri_id)) {
 					Post\Media::copy($old_uri_id, $datarray["uri-id"]);
 				}
+
+				unset($datarray["parent-uri"]);
+				unset($datarray["thr-parent"]);
 			} else {
 				$datarray['private'] = self::PUBLIC;
 			}
@@ -3297,7 +3297,6 @@ class Item
 			'network'       => Protocol::DFRN,
 			'gravity'       => GRAVITY_ACTIVITY,
 			'parent'        => $item['id'],
-			'parent-uri'    => $item['uri'],
 			'thr-parent'    => $item['uri'],
 			'owner-id'      => $author_id,
 			'author-id'     => $author_id,
diff --git a/src/Module/Contact/Poke.php b/src/Module/Contact/Poke.php
index 9f2ae7bde..d9fab36c0 100644
--- a/src/Module/Contact/Poke.php
+++ b/src/Module/Contact/Poke.php
@@ -67,7 +67,6 @@ class Poke extends BaseModule
 		$arr['guid']          = System::createUUID();
 		$arr['uid']           = $uid;
 		$arr['uri']           = $uri;
-		$arr['parent-uri']    = $uri;
 		$arr['wall']          = 1;
 		$arr['contact-id']    = $actor['id'];
 		$arr['owner-name']    = $actor['name'];
diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index 93dff93ae..8f1e94580 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -625,6 +625,7 @@ class OnePoll
 					if (empty($datarray['parent-uri'])) {
 						$datarray['parent-uri'] = $datarray['uri'];
 					}
+					unset($datarray['parent-uri']);
 
 					$headers = imap_headerinfo($mbox, $meta->msgno);
 

From 0f2a5daf09b67c85b8c61b3db346697c612edf61 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 02:47:48 -0500
Subject: [PATCH 03/18] Replace confusing uses of item.parent-uri with expected
 item.thr-parent

---
 mod/item.php              |  5 ++-
 mod/tagger.php            |  2 +-
 src/Protocol/DFRN.php     | 39 ++++++++++++------------
 src/Protocol/Diaspora.php | 64 ++++++++++++++++++---------------------
 src/Protocol/Feed.php     |  8 ++---
 src/Protocol/OStatus.php  | 31 +++++++++----------
 src/Worker/OnePoll.php    |  6 ++--
 7 files changed, 74 insertions(+), 81 deletions(-)

diff --git a/mod/item.php b/mod/item.php
index 9828d1acb..3869ea910 100644
--- a/mod/item.php
+++ b/mod/item.php
@@ -605,8 +605,7 @@ function item_post(App $a) {
 	$datarray['pubmail']       = $pubmail_enabled;
 	$datarray['attach']        = $attachments;
 
-	// This is not a bug. The item store function changes 'parent-uri' to 'thr-parent' and fetches 'parent-uri' new. (We should change this)
-	$datarray['parent-uri']    = $thr_parent_uri;
+	$datarray['thr-parent']    = $thr_parent_uri;
 
 	$datarray['postopts']      = $postopts;
 	$datarray['origin']        = $origin;
@@ -627,7 +626,7 @@ function item_post(App $a) {
 	// This field is for storing the raw conversation data
 	$datarray['protocol'] = Conversation::PARCEL_DFRN;
 
-	$conversation = DBA::selectFirst('conversation', ['conversation-uri', 'conversation-href'], ['item-uri' => $datarray['parent-uri']]);
+	$conversation = DBA::selectFirst('conversation', ['conversation-uri', 'conversation-href'], ['item-uri' => $datarray['thr-parent']]);
 	if (DBA::isResult($conversation)) {
 		if ($conversation['conversation-uri'] != '') {
 			$datarray['conversation-uri'] = $conversation['conversation-uri'];
diff --git a/mod/tagger.php b/mod/tagger.php
index 86a6ff69f..63e7f2ca8 100644
--- a/mod/tagger.php
+++ b/mod/tagger.php
@@ -136,7 +136,7 @@ EOT;
 	$arr['wall'] = $item['wall'];
 	$arr['gravity'] = GRAVITY_COMMENT;
 	$arr['parent'] = $item['id'];
-	$arr['parent-uri'] = $item['uri'];
+	$arr['thr-parent'] = $item['uri'];
 	$arr['owner-name'] = $item['author-name'];
 	$arr['owner-link'] = $item['author-link'];
 	$arr['owner-avatar'] = $item['author-avatar'];
diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 11c4e3a14..165a63c7c 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -438,7 +438,7 @@ class DFRN
 		$mail->appendChild($sender);
 
 		XML::addElement($doc, $mail, "dfrn:id", $item['uri']);
-		XML::addElement($doc, $mail, "dfrn:in-reply-to", $item['parent-uri']);
+		XML::addElement($doc, $mail, "dfrn:in-reply-to", $item['thr-parent']);
 		XML::addElement($doc, $mail, "dfrn:sentdate", DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM));
 		XML::addElement($doc, $mail, "dfrn:subject", $item['title']);
 		XML::addElement($doc, $mail, "dfrn:content", $item['body']);
@@ -956,10 +956,9 @@ class DFRN
 		$entry->appendChild($dfrnowner);
 
 		if ($item['gravity'] != GRAVITY_PARENT) {
-			$parent_item = (($item['thr-parent']) ? $item['thr-parent'] : $item['parent-uri']);
-			$parent = Item::selectFirst(['guid', 'plink'], ['uri' => $parent_item, 'uid' => $item['uid']]);
+			$parent = Item::selectFirst(['guid', 'plink'], ['uri' => $item['thr-parent'], 'uid' => $item['uid']]);
 			if (DBA::isResult($parent)) {
-				$attributes = ["ref" => $parent_item, "type" => "text/html",
+				$attributes = ["ref" => $item['thr-parent'], "type" => "text/html",
 					"href" => $parent['plink'],
 					"dfrn:diaspora_guid" => $parent['guid']];
 				XML::addElement($doc, $entry, "thr:in-reply-to", "", $attributes);
@@ -971,7 +970,7 @@ class DFRN
 		$conversation_uri = $conversation_href;
 
 		if (isset($parent_item)) {
-			$conversation = DBA::selectFirst('conversation', ['conversation-uri', 'conversation-href'], ['item-uri' => $item['parent-uri']]);
+			$conversation = DBA::selectFirst('conversation', ['conversation-uri', 'conversation-href'], ['item-uri' => $item['thr-parent']]);
 			if (DBA::isResult($conversation)) {
 				if ($conversation['conversation-uri'] != '') {
 					$conversation_uri = $conversation['conversation-uri'];
@@ -1768,7 +1767,7 @@ class DFRN
 		$msg["from-photo"] = XML::getFirstValue($xpath, "dfrn:sender/dfrn:avatar/text()", $mail);
 		$msg["contact-id"] = $importer["id"];
 		$msg["uri"] = XML::getFirstValue($xpath, "dfrn:id/text()", $mail);
-		$msg["parent-uri"] = XML::getFirstValue($xpath, "dfrn:in-reply-to/text()", $mail);
+		$msg["thr-parent"] = XML::getFirstValue($xpath, "dfrn:in-reply-to/text()", $mail);
 		$msg["created"] = DateTimeFormat::utc(XML::getFirstValue($xpath, "dfrn:sentdate/text()", $mail));
 		$msg["title"] = XML::getFirstValue($xpath, "dfrn:subject/text()", $mail);
 		$msg["body"] = XML::getFirstValue($xpath, "dfrn:content/text()", $mail);
@@ -1918,7 +1917,7 @@ class DFRN
 	 */
 	private static function getEntryType($importer, $item)
 	{
-		if ($item["parent-uri"] != $item["uri"]) {
+		if ($item["thr-parent"] != $item["uri"]) {
 			$community = false;
 
 			if ($importer["page-flags"] == User::PAGE_FLAGS_COMMUNITY || $importer["page-flags"] == User::PAGE_FLAGS_PRVGROUP) {
@@ -1934,18 +1933,18 @@ class DFRN
 
 			$is_a_remote_action = false;
 
-			$parent = Item::selectFirst(['parent-uri'], ['uri' => $item["parent-uri"]]);
+			$parent = Item::selectFirst(['thr-parent'], ['uri' => $item["thr-parent"]]);
 			if (DBA::isResult($parent)) {
 				$r = q(
 					"SELECT `item`.`forum_mode`, `item`.`wall` FROM `item`
 					INNER JOIN `contact` ON `contact`.`id` = `item`.`contact-id`
-					WHERE `item`.`uri` = '%s' AND (`item`.`parent-uri` = '%s' OR `item`.`thr-parent` = '%s')
+					WHERE `item`.`uri` = '%s' AND (`item`.`thr-parent` = '%s' OR `item`.`thr-parent` = '%s')
 					AND `item`.`uid` = %d
 					$sql_extra
 					LIMIT 1",
-					DBA::escape($parent["parent-uri"]),
-					DBA::escape($parent["parent-uri"]),
-					DBA::escape($parent["parent-uri"]),
+					DBA::escape($parent["thr-parent"]),
+					DBA::escape($parent["thr-parent"]),
+					DBA::escape($parent["thr-parent"]),
 					intval($importer["importer_uid"])
 				);
 				if (DBA::isResult($r)) {
@@ -2008,7 +2007,7 @@ class DFRN
 			if ($Blink && Strings::compareLink($Blink, DI::baseUrl() . "/profile/" . $importer["nickname"])) {
 				$author = DBA::selectFirst('contact', ['name', 'thumb', 'url'], ['id' => $item['author-id']]);
 
-				$parent = Item::selectFirst(['id'], ['uri' => $item['parent-uri'], 'uid' => $importer["importer_uid"]]);
+				$parent = Item::selectFirst(['id'], ['uri' => $item['thr-parent'], 'uid' => $importer["importer_uid"]]);
 				$item['parent'] = $parent['id'];
 
 				// send a notification
@@ -2090,15 +2089,15 @@ class DFRN
 				$is_like = true;
 				$item["gravity"] = GRAVITY_ACTIVITY;
 				// only one like or dislike per person
-				// splitted into two queries for performance issues
+				// split into two queries for performance issues
 				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"], 'gravity' => GRAVITY_ACTIVITY,
-					'verb' => $item["verb"], 'parent-uri' => $item["parent-uri"]];
+					'verb' => $item['verb'], 'parent-uri' => $item['thr-parent']];
 				if (Item::exists($condition)) {
 					return false;
 				}
 
 				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"], 'gravity' => GRAVITY_ACTIVITY,
-					'verb' => $item["verb"], 'thr-parent' => $item["parent-uri"]];
+					'verb' => $item['verb'], 'thr-parent' => $item['thr-parent']];
 				if (Item::exists($condition)) {
 					return false;
 				}
@@ -2370,19 +2369,19 @@ class DFRN
 		}
 
 		// Is it a reply or a top level posting?
-		$item["parent-uri"] = $item["uri"];
+		$item['thr-parent'] = $item['uri'];
 
 		$inreplyto = $xpath->query("thr:in-reply-to", $entry);
 		if (is_object($inreplyto->item(0))) {
 			foreach ($inreplyto->item(0)->attributes as $attributes) {
 				if ($attributes->name == "ref") {
-					$item["parent-uri"] = $attributes->textContent;
+					$item['thr-parent'] = $attributes->textContent;
 				}
 			}
 		}
 
 		// Check if the message is wanted
-		if (($importer["importer_uid"] == 0) && ($item['uri'] == $item['parent-uri'])) {
+		if (($importer['importer_uid'] == 0) && ($item['uri'] == $item['thr-parent'])) {
 			if (!self::isSolicitedMessage($item)) {
 				DBA::delete('item-uri', ['uri' => $item['uri']]);
 				return 403;
@@ -2760,7 +2759,7 @@ class DFRN
 
 		// check that the message originated elsewhere and is a top-level post
 
-		if ($item['wall'] || $item['origin'] || ($item['uri'] != $item['parent-uri'])) {
+		if ($item['wall'] || $item['origin'] || ($item['uri'] != $item['thr-parent'])) {
 			return false;
 		}
 
diff --git a/src/Protocol/Diaspora.php b/src/Protocol/Diaspora.php
index 8c93d7c0f..04d076c03 100644
--- a/src/Protocol/Diaspora.php
+++ b/src/Protocol/Diaspora.php
@@ -1697,9 +1697,9 @@ class Diaspora
 
 		if (isset($data->thread_parent_guid)) {
 			$thread_parent_guid = Strings::escapeTags(XML::unescape($data->thread_parent_guid));
-			$thr_uri = self::getUriFromGuid("", $thread_parent_guid, true);
+			$thr_parent = self::getUriFromGuid("", $thread_parent_guid, true);
 		} else {
-			$thr_uri = "";
+			$thr_parent = "";
 		}
 
 		$contact = self::allowedContactByHandle($importer, $sender, true);
@@ -1712,8 +1712,8 @@ class Diaspora
 			return true;
 		}
 
-		$parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
-		if (!$parent_item) {
+		$toplevel_parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
+		if (!$toplevel_parent_item) {
 			return false;
 		}
 
@@ -1754,11 +1754,8 @@ class Diaspora
 		$datarray["verb"] = Activity::POST;
 		$datarray["gravity"] = GRAVITY_COMMENT;
 
-		if ($thr_uri != "") {
-			$datarray["parent-uri"] = $thr_uri;
-		} else {
-			$datarray["parent-uri"] = $parent_item["uri"];
-		}
+		$datarray['thr-parent'] = $thr_parent ?: $toplevel_parent_item['uri'];
+		$datarray['parent-uri'] = $toplevel_parent_item['uri'];
 
 		$datarray["object-type"] = Activity\ObjectType::COMMENT;
 
@@ -1767,7 +1764,7 @@ class Diaspora
 
 		$datarray["changed"] = $datarray["created"] = $datarray["edited"] = $created_at;
 
-		$datarray["plink"] = self::plink($author, $guid, $parent_item['guid']);
+		$datarray["plink"] = self::plink($author, $guid, $toplevel_parent_item['guid']);
 		$body = Markdown::toBBCode($text);
 
 		$datarray["body"] = self::replacePeopleGuid($body, $person["url"]);
@@ -1779,7 +1776,7 @@ class Diaspora
 
 		// If we are the origin of the parent we store the original data.
 		// We notify our followers during the item storage.
-		if ($parent_item["origin"]) {
+		if ($toplevel_parent_item["origin"]) {
 			$datarray['diaspora_signed_text'] = json_encode($data);
 		}
 
@@ -1953,8 +1950,8 @@ class Diaspora
 			return true;
 		}
 
-		$parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
-		if (!$parent_item) {
+		$toplevel_parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
+		if (!$toplevel_parent_item) {
 			return false;
 		}
 
@@ -1991,7 +1988,7 @@ class Diaspora
 
 		$datarray["verb"] = $verb;
 		$datarray["gravity"] = GRAVITY_ACTIVITY;
-		$datarray["parent-uri"] = $parent_item["uri"];
+		$datarray['thr-parent'] = $toplevel_parent_item['uri'];
 
 		$datarray["object-type"] = Activity\ObjectType::NOTE;
 
@@ -2001,11 +1998,11 @@ class Diaspora
 		$datarray["changed"] = $datarray["created"] = $datarray["edited"] = DateTimeFormat::utcNow();
 
 		// like on comments have the comment as parent. So we need to fetch the toplevel parent
-		if ($parent_item['gravity'] != GRAVITY_PARENT) {
-			$toplevel = Item::selectFirst(['origin'], ['id' => $parent_item['parent']]);
+		if ($toplevel_parent_item['gravity'] != GRAVITY_PARENT) {
+			$toplevel = Item::selectFirst(['origin'], ['id' => $toplevel_parent_item['parent']]);
 			$origin = $toplevel["origin"];
 		} else {
-			$origin = $parent_item["origin"];
+			$origin = $toplevel_parent_item["origin"];
 		}
 
 		// If we are the origin of the parent we store the original data.
@@ -2116,16 +2113,16 @@ class Diaspora
 			return true;
 		}
 
-		$parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
-		if (!$parent_item) {
+		$toplevel_parent_item = self::parentItem($importer["uid"], $parent_guid, $author, $contact);
+		if (!$toplevel_parent_item) {
 			return false;
 		}
 
-		if (!$parent_item['origin']) {
+		if (!$toplevel_parent_item['origin']) {
 			Logger::info('Not our origin. Participation is ignored', ['parent_guid' => $parent_guid, 'guid' => $guid, 'author' => $author]);
 		}
 
-		if (!in_array($parent_item['private'], [Item::PUBLIC, Item::UNLISTED])) {
+		if (!in_array($toplevel_parent_item['private'], [Item::PUBLIC, Item::UNLISTED])) {
 			Logger::info('Item is not public, participation is ignored', ['parent_guid' => $parent_guid, 'guid' => $guid, 'author' => $author]);
 			return false;
 		}
@@ -2155,7 +2152,8 @@ class Diaspora
 
 		$datarray["verb"] = Activity::FOLLOW;
 		$datarray["gravity"] = GRAVITY_ACTIVITY;
-		$datarray["parent-uri"] = $parent_item["uri"];
+		$datarray['thr-parent'] = $toplevel_parent_item['uri'];
+		$datarray['parent-uri'] = $toplevel_parent_item['parent-uri'];
 
 		$datarray["object-type"] = Activity\ObjectType::NOTE;
 
@@ -2170,7 +2168,7 @@ class Diaspora
 
 		// Send all existing comments and likes to the requesting server
 		$comments = Item::select(['id', 'uri-id', 'parent-author-network', 'author-network', 'verb'],
-			['parent' => $parent_item['id'], 'gravity' => [GRAVITY_COMMENT, GRAVITY_ACTIVITY]]);
+			['parent' => $toplevel_parent_item['id'], 'gravity' => [GRAVITY_COMMENT, GRAVITY_ACTIVITY]]);
 		while ($comment = Item::fetch($comments)) {
 			if (in_array($comment['verb'], [Activity::FOLLOW, Activity::TAG])) {
 				Logger::info('participation messages are not relayed', ['item' => $comment['id']]);
@@ -2547,7 +2545,8 @@ class Diaspora
 
 		$datarray['guid'] = $parent['guid'] . '-' . $guid;
 		$datarray['uri'] = self::getUriFromGuid($author, $datarray['guid']);
-		$datarray['parent-uri'] = $parent['uri'];
+		$datarray['thr-parent'] = $parent['uri'];
+		$datarray['parent-uri'] = $parent['parent-uri'];
 
 		$datarray['verb'] = $datarray['body'] = Activity::ANNOUNCE;
 		$datarray['gravity'] = GRAVITY_ACTIVITY;
@@ -2618,7 +2617,7 @@ class Diaspora
 		$datarray["owner-id"] = $datarray["author-id"];
 
 		$datarray["guid"] = $guid;
-		$datarray["uri"] = $datarray["parent-uri"] = self::getUriFromGuid($author, $guid);
+		$datarray["uri"] = $datarray["thr-parent"] = self::getUriFromGuid($author, $guid);
 		$datarray['uri-id'] = ItemURI::insert(['uri' => $datarray['uri'], 'guid' => $datarray['guid']]);
 
 		$datarray["verb"] = Activity::POST;
@@ -2703,7 +2702,7 @@ class Diaspora
 		}
 
 		// Fetch items that are about to be deleted
-		$fields = ['uid', 'id', 'parent', 'parent-uri', 'author-link', 'file'];
+		$fields = ['uid', 'id', 'parent', 'author-link', 'file'];
 
 		// When we receive a public retraction, we delete every item that we find.
 		if ($importer['uid'] == 0) {
@@ -2872,7 +2871,7 @@ class Diaspora
 		$datarray = [];
 
 		$datarray["guid"] = $guid;
-		$datarray["uri"] = $datarray["parent-uri"] = self::getUriFromGuid($author, $guid);
+		$datarray["uri"] = $datarray["thr-parent"] = self::getUriFromGuid($author, $guid);
 		$datarray['uri-id'] = ItemURI::insert(['uri' => $datarray['uri'], 'guid' => $datarray['guid']]);
 
 		// Attach embedded pictures to the body
@@ -3681,12 +3680,12 @@ class Diaspora
 	 */
 	private static function constructLike(array $item, array $owner)
 	{
-		$parent = Item::selectFirst(['guid', 'uri', 'parent-uri'], ['uri' => $item["thr-parent"]]);
+		$parent = Item::selectFirst(['guid', 'uri', 'thr-parent'], ['uri' => $item["thr-parent"]]);
 		if (!DBA::isResult($parent)) {
 			return false;
 		}
 
-		$target_type = ($parent["uri"] === $parent["parent-uri"] ? "Post" : "Comment");
+		$target_type = ($parent["uri"] === $parent["thr-parent"] ? "Post" : "Comment");
 		$positive = null;
 		if ($item['verb'] === Activity::LIKE) {
 			$positive = "true";
@@ -3713,7 +3712,7 @@ class Diaspora
 	 */
 	private static function constructAttend(array $item, array $owner)
 	{
-		$parent = Item::selectFirst(['guid', 'uri', 'parent-uri'], ['uri' => $item["thr-parent"]]);
+		$parent = Item::selectFirst(['guid'], ['uri' => $item['thr-parent']]);
 		if (!DBA::isResult($parent)) {
 			return false;
 		}
@@ -4242,10 +4241,7 @@ class Diaspora
 			return false;
 		}
 
-		// This is a workaround for the behaviour of the "insert" function, see mod/item.php
-		$item['thr-parent'] = $item['parent-uri'];
-
-		$parent = Item::selectFirst(['parent-uri'], ['uri' => $item['parent-uri']]);
+		$parent = Item::selectFirst(['parent-uri'], ['uri' => $item['thr-parent']]);
 		if (!DBA::isResult($parent)) {
 			return;
 		}
diff --git a/src/Protocol/Feed.php b/src/Protocol/Feed.php
index fee765f25..c7d19a996 100644
--- a/src/Protocol/Feed.php
+++ b/src/Protocol/Feed.php
@@ -354,7 +354,7 @@ class Feed
 
 			$item["plink"] = DI::httpRequest()->finalUrl($item["plink"]);
 
-			$item["parent-uri"] = $item["uri"];
+			$item["thr-parent"] = $item["uri"];
 
 			$item["title"] = XML::getFirstNodeValue($xpath, 'atom:title/text()', $entry);
 
@@ -602,6 +602,7 @@ class Feed
 			if ($notify) {
 				$item['guid'] = Item::guidFromUri($orig_plink, DI::baseUrl()->getHostname());
 				unset($item['uri']);
+				unset($item['thr-parent']);
 				unset($item['parent-uri']);
 
 				// Set the delivery priority for "remote self" to "medium"
@@ -1108,9 +1109,8 @@ class Feed
 
 		if ($item['gravity'] != GRAVITY_PARENT) {
 			$parent = Item::selectFirst(['guid', 'author-link', 'owner-link'], ['id' => $item['parent']]);
-			$parent_item = (($item['thr-parent']) ? $item['thr-parent'] : $item['parent-uri']);
 
-			$thrparent = Item::selectFirst(['guid', 'author-link', 'owner-link', 'plink'], ['uid' => $owner["uid"], 'uri' => $parent_item]);
+			$thrparent = Item::selectFirst(['guid', 'author-link', 'owner-link', 'plink'], ['uid' => $owner["uid"], 'uri' => $item['thr-parent']]);
 
 			if (DBA::isResult($thrparent)) {
 				$mentioned[$thrparent["author-link"]] = $thrparent["author-link"];
@@ -1123,7 +1123,7 @@ class Feed
 			}
 
 			$attributes = [
-					"ref" => $parent_item,
+					"ref" => $item['thr-parent'],
 					"href" => $parent_plink];
 			XML::addElement($doc, $entry, "thr:in-reply-to", "", $attributes);
 
diff --git a/src/Protocol/OStatus.php b/src/Protocol/OStatus.php
index e394877b3..9218f2665 100644
--- a/src/Protocol/OStatus.php
+++ b/src/Protocol/OStatus.php
@@ -482,7 +482,7 @@ class OStatus
 				Logger::log("Favorite ".$orig_uri." ".print_r($item, true));
 
 				$item["verb"] = Activity::LIKE;
-				$item["parent-uri"] = $orig_uri;
+				$item["thr-parent"] = $orig_uri;
 				$item["gravity"] = GRAVITY_ACTIVITY;
 				$item["object-type"] = Activity\ObjectType::NOTE;
 			}
@@ -495,7 +495,7 @@ class OStatus
 			self::processPost($xpath, $entry, $item, $importer);
 
 			if ($initialize && (count(self::$itemlist) > 0)) {
-				if (self::$itemlist[0]['uri'] == self::$itemlist[0]['parent-uri']) {
+				if (self::$itemlist[0]['uri'] == self::$itemlist[0]['thr-parent']) {
 					// We will import it everytime, when it is started by our contacts
 					$valid = Contact::isSharingByURL(self::$itemlist[0]['author-link'], self::$itemlist[0]['uid']);
 
@@ -523,9 +523,9 @@ class OStatus
 					}
 				} else {
 					// But we will only import complete threads
-					$valid = Item::exists(['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['parent-uri']]);
+					$valid = Item::exists(['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['thr-parent']]);
 					if ($valid) {
-						Logger::log("Item with uri ".self::$itemlist[0]["uri"]." belongs to parent ".self::$itemlist[0]['parent-uri']." of user ".$importer["uid"].". It will be imported.", Logger::DEBUG);
+						Logger::log("Item with uri ".self::$itemlist[0]["uri"]." belongs to parent ".self::$itemlist[0]['thr-parent']." of user ".$importer["uid"].". It will be imported.", Logger::DEBUG);
 					}
 				}
 
@@ -621,7 +621,7 @@ class OStatus
 		if (is_object($inreplyto->item(0))) {
 			foreach ($inreplyto->item(0)->attributes as $attributes) {
 				if ($attributes->name == "ref") {
-					$item["parent-uri"] = $attributes->textContent;
+					$item["thr-parent"] = $attributes->textContent;
 				}
 				if ($attributes->name == "href") {
 					$related = $attributes->textContent;
@@ -702,16 +702,16 @@ class OStatus
 			self::fetchConversation($item['conversation-href'], $item['conversation-uri']);
 		}
 
-		if (isset($item["parent-uri"])) {
-			if (!Item::exists(['uid' => $importer["uid"], 'uri' => $item['parent-uri']])) {
+		if (isset($item["thr-parent"])) {
+			if (!Item::exists(['uid' => $importer["uid"], 'uri' => $item['thr-parent']])) {
 				if ($related != '') {
-					self::fetchRelated($related, $item["parent-uri"], $importer);
+					self::fetchRelated($related, $item["thr-parent"], $importer);
 				}
 			} else {
 				Logger::log('Reply with URI '.$item["uri"].' already existed for user '.$importer["uid"].'.', Logger::DEBUG);
 			}
 		} else {
-			$item["parent-uri"] = $item["uri"];
+			$item["thr-parent"] = $item["uri"];
 			$item["gravity"] = GRAVITY_PARENT;
 		}
 
@@ -1074,7 +1074,7 @@ class OStatus
 		if (is_object($inreplyto->item(0))) {
 			foreach ($inreplyto->item(0)->attributes as $attributes) {
 				if ($attributes->name == "ref") {
-					$item["parent-uri"] = $attributes->textContent;
+					$item["thr-parent"] = $attributes->textContent;
 				}
 			}
 		}
@@ -1126,8 +1126,8 @@ class OStatus
 						break;
 					case "related":
 						if ($item["object-type"] != Activity\ObjectType::BOOKMARK) {
-							if (!isset($item["parent-uri"])) {
-								$item["parent-uri"] = $attribute['href'];
+							if (!isset($item["thr-parent"])) {
+								$item["thr-parent"] = $attribute['href'];
 							}
 							$link_data['related'] = $attribute['href'];
 						} else {
@@ -1934,9 +1934,8 @@ class OStatus
 
 		if ($item['gravity'] != GRAVITY_PARENT) {
 			$parent = Item::selectFirst(['guid', 'author-link', 'owner-link'], ['id' => $item['parent']]);
-			$parent_item = (($item['thr-parent']) ? $item['thr-parent'] : $item['parent-uri']);
 
-			$thrparent = Item::selectFirst(['guid', 'author-link', 'owner-link', 'plink'], ['uid' => $owner["uid"], 'uri' => $parent_item]);
+			$thrparent = Item::selectFirst(['guid', 'author-link', 'owner-link', 'plink'], ['uid' => $owner["uid"], 'uri' => $item['thr-parent']]);
 
 			if (DBA::isResult($thrparent)) {
 				$mentioned[$thrparent["author-link"]] = $thrparent["author-link"];
@@ -1949,7 +1948,7 @@ class OStatus
 			}
 
 			$attributes = [
-					"ref" => $parent_item,
+					"ref" => $item['thr-parent'],
 					"href" => $parent_plink];
 			XML::addElement($doc, $entry, "thr:in-reply-to", "", $attributes);
 
@@ -1960,7 +1959,7 @@ class OStatus
 		}
 
 		if (intval($item['parent']) > 0) {
-			$conversation_href = $conversation_uri = str_replace('/objects/', '/context/', $item['parent-uri']);
+			$conversation_href = $conversation_uri = str_replace('/objects/', '/context/', $item['thr-parent']);
 
 			if (isset($parent_item)) {
 				$conversation = DBA::selectFirst('conversation', ['conversation-uri', 'conversation-href'], ['item-uri' => $parent_item]);
diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index 8f1e94580..bdef1ac4d 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -622,8 +622,8 @@ class OnePoll
 						}
 					}
 
-					if (empty($datarray['parent-uri'])) {
-						$datarray['parent-uri'] = $datarray['uri'];
+					if (!empty($datarray['parent-uri'])) {
+						$datarray['thr-parent'] = $datarray['parent-uri'];
 					}
 					unset($datarray['parent-uri']);
 
@@ -664,7 +664,7 @@ class OnePoll
 					$datarray['owner-link'] = "mailto:".$contact['addr'];
 					$datarray['owner-avatar'] = $contact['photo'];
 
-					if ($datarray['parent-uri'] === $datarray['uri']) {
+					if ($datarray['thr-parent'] === $datarray['uri']) {
 						$datarray['private'] = Item::PRIVATE;
 					}
 

From 5e76def1ff1269b4e21297f5ce18e58f60996b64 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 02:48:52 -0500
Subject: [PATCH 04/18] Clarify item.parent-uri use in database field comment

---
 static/dbstructure.config.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/static/dbstructure.config.php b/static/dbstructure.config.php
index 9fb0c9911..d1da02412 100644
--- a/static/dbstructure.config.php
+++ b/static/dbstructure.config.php
@@ -709,8 +709,8 @@ return [
 			"uri-id" => ["type" => "int unsigned", "foreign" => ["item-uri" => "id"], "comment" => "Id of the item-uri table entry that contains the item uri"],
 			"uri-hash" => ["type" => "varchar(80)", "not null" => "1", "default" => "", "comment" => "RIPEMD-128 hash from uri"],
 			"parent" => ["type" => "int unsigned", "not null" => "1", "default" => "0", "relation" => ["item" => "id"], "comment" => "item.id of the parent to this item if it is a reply of some form; otherwise this must be set to the id of this item"],
-			"parent-uri" => ["type" => "varchar(255)", "not null" => "1", "default" => "", "comment" => "uri of the parent to this item"],
-			"parent-uri-id" => ["type" => "int unsigned", "foreign" => ["item-uri" => "id"], "comment" => "Id of the item-uri table that contains the parent uri"],
+			"parent-uri" => ["type" => "varchar(255)", "not null" => "1", "default" => "", "comment" => "uri of the top-level parent to this item"],
+			"parent-uri-id" => ["type" => "int unsigned", "foreign" => ["item-uri" => "id"], "comment" => "Id of the item-uri table that contains the top-level parent uri"],
 			"thr-parent" => ["type" => "varchar(255)", "not null" => "1", "default" => "", "comment" => "If the parent of this item is not the top-level item in the conversation, the uri of the immediate parent; otherwise set to parent-uri"],
 			"thr-parent-id" => ["type" => "int unsigned", "foreign" => ["item-uri" => "id"], "comment" => "Id of the item-uri table that contains the thread parent uri"],
 			"created" => ["type" => "datetime", "not null" => "1", "default" => DBA::NULL_DATETIME, "comment" => "Creation timestamp."],

From ffc364f2a4c8ed14c28fa01061d11c4f1a28af06 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 02:50:22 -0500
Subject: [PATCH 05/18] Reject replies when author is blocked by thread owner
 in Model\Item::insert

- Move user-level item permission to Model\Item::isAllowedByUser
- Add user-level check for comments on top-level item
---
 src/Model/Contact/User.php |  4 +--
 src/Model/Item.php         | 63 +++++++++++++++++++++++++++-----------
 2 files changed, 47 insertions(+), 20 deletions(-)

diff --git a/src/Model/Contact/User.php b/src/Model/Contact/User.php
index 34a3d6f34..be60c119b 100644
--- a/src/Model/Contact/User.php
+++ b/src/Model/Contact/User.php
@@ -64,7 +64,7 @@ class User
 	{
 		$cdata = Contact::getPublicAndUserContacID($cid, $uid);
 		if (empty($cdata)) {
-			return;
+			return false;
 		}
 
 		$public_blocked = false;
@@ -127,7 +127,7 @@ class User
 	{
 		$cdata = Contact::getPublicAndUserContacID($cid, $uid);
 		if (empty($cdata)) {
-			return;
+			return false;
 		}
 
 		$public_ignored = false;
diff --git a/src/Model/Item.php b/src/Model/Item.php
index e67b86234..3239c4a8f 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1415,11 +1415,6 @@ class Item
 			return false;
 		}
 
-		if (!empty($item['uid']) && !empty($item['author-id']) && Contact\User::isBlocked($item['author-id'], $item['uid'])) {
-			Logger::notice('Author is blocked by user', ['author-link' => $item['author-link'], 'uid' => $item['uid'], 'item-uri' => $item['uri']]);
-			return false;
-		}
-
 		if (!empty($item['owner-id']) && Contact::isBlocked($item['owner-id'])) {
 			Logger::notice('Owner is blocked node-wide', ['owner-link' => $item['owner-link'], 'item-uri' => $item['uri']]);
 			return false;
@@ -1430,22 +1425,10 @@ class Item
 			return false;
 		}
 
-		if (!empty($item['uid']) && !empty($item['owner-id']) && Contact\User::isBlocked($item['owner-id'], $item['uid'])) {
-			Logger::notice('Owner is blocked by user', ['owner-link' => $item['owner-link'], 'uid' => $item['uid'], 'item-uri' => $item['uri']]);
+		if (!empty($item['uid']) && !self::isAllowedByUser($item, $item['uid'])) {
 			return false;
 		}
 
-		// The causer is set during a thread completion, for example because of a reshare. It countains the responsible actor.
-		if (!empty($item['uid']) && !empty($item['causer-id']) && Contact\User::isBlocked($item['causer-id'], $item['uid'])) {
-			Logger::notice('Causer is blocked by user', ['causer-link' => $item['causer-link'], 'uid' => $item['uid'], 'item-uri' => $item['uri']]);
-			return false;
-		}
-
-		if (!empty($item['uid']) && !empty($item['causer-id']) && ($item['parent-uri'] == $item['uri']) && Contact\User::isIgnored($item['causer-id'], $item['uid'])) {
-			Logger::notice('Causer is ignored by user', ['causer-link' => $item['causer-link'], 'uid' => $item['uid'], 'item-uri' => $item['uri']]);
-			return false;
-		}
-		
 		if ($item['verb'] == Activity::FOLLOW) {
 			if (!$item['origin'] && ($item['author-id'] == Contact::getPublicIdByUserId($item['uid']))) {
 				// Our own follow request can be relayed to us. We don't store it to avoid notification chaos.
@@ -1533,6 +1516,13 @@ class Item
 			return [];
 		}
 
+		if ($toplevel_parent['wall']
+			&& $toplevel_parent['uid'] &&
+			!self::isAllowedByUser($item, $toplevel_parent['uid'])
+		) {
+			return [];
+		}
+
 		return $toplevel_parent;
 	}
 
@@ -3955,4 +3945,41 @@ class Item
 
 		return array_merge($item, $shared_item);
 	}
+
+	/**
+	 * Check a prospective item array against user-level permissions
+	 *
+	 * @param array $item Expected keys: uri, gravity, and
+	 *                    author-link if is author-id is set,
+	 *                    owner-link if is owner-id is set,
+	 *                    causer-link if is causer-id is set.
+	 * @param int   $user_id Local user ID
+	 * @return bool
+	 * @throws \Exception
+	 */
+	protected static function isAllowedByUser(array $item, int $user_id)
+	{
+		if (!empty($item['author-id']) && Contact\User::isBlocked($item['author-id'], $user_id)) {
+			Logger::notice('Author is blocked by user', ['author-link' => $item['author-link'], 'uid' => $user_id, 'item-uri' => $item['uri']]);
+			return false;
+		}
+
+		if (!empty($item['owner-id']) && Contact\User::isBlocked($item['owner-id'], $user_id)) {
+			Logger::notice('Owner is blocked by user', ['owner-link' => $item['owner-link'], 'uid' => $user_id, 'item-uri' => $item['uri']]);
+			return false;
+		}
+
+		// The causer is set during a thread completion, for example because of a reshare. It countains the responsible actor.
+		if (!empty($item['causer-id']) && Contact\User::isBlocked($item['causer-id'], $user_id)) {
+			Logger::notice('Causer is blocked by user', ['causer-link' => $item['causer-link'], 'uid' => $user_id, 'item-uri' => $item['uri']]);
+			return false;
+		}
+
+		if (!empty($item['causer-id']) && ($item['gravity'] === GRAVITY_PARENT) && Contact\User::isIgnored($item['causer-id'], $user_id)) {
+			Logger::notice('Causer is ignored by user', ['causer-link' => $item['causer-link'], 'uid' => $user_id, 'item-uri' => $item['uri']]);
+			return false;
+		}
+
+		return true;
+	}
 }

From 355cd401ae077bad6f3e37cf4e41004ff7570e72 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 10:07:39 -0500
Subject: [PATCH 06/18] Replace uri fields conditions by gravity condition in
 Model\Item::insert

---
 src/Model/Item.php | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index 3239c4a8f..a8ac82ede 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1576,7 +1576,7 @@ class Item
 		$uid = intval($item['uid']);
 
 		$item['guid'] = self::guid($item, $notify);
-		$item['uri'] = substr(Strings::escapeTags(trim(($item['uri'] ?? '') ?: self::newURI($item['uid'], $item['guid']))), 0, 255);
+		$item['uri'] = substr(trim($item['uri'] ?? '') ?: self::newURI($item['uid'], $item['guid']), 0, 255);
 
 		// Store URI data
 		$item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
@@ -1685,7 +1685,7 @@ class Item
 			return 0;
 		}
 
-		if ($item['thr-parent'] != $item['uri']) {
+		if ($item['gravity'] !== GRAVITY_PARENT) {
 			$toplevel_parent = self::getTopLevelParent($item);
 			if (empty($toplevel_parent)) {
 				return 0;
@@ -1917,7 +1917,7 @@ class Item
 
 		Logger::notice('created item', ['id' => $current_post, 'uid' => $item['uid'], 'network' => $item['network'], 'uri-id' => $item['uri-id'], 'guid' => $item['guid']]);
 
-		if (!$parent_id || ($item['parent-uri'] === $item['uri'])) {
+		if (!$parent_id || ($item['gravity'] === GRAVITY_PARENT)) {
 			$parent_id = $current_post;
 		}
 
@@ -1942,7 +1942,7 @@ class Item
 			DBA::update('item', ['changed' => DateTimeFormat::utcNow()], ['id' => $parent_id]);
 		}
 
-		if ($item['parent-uri'] === $item['uri']) {
+		if ($item['gravity'] === GRAVITY_PARENT) {
 			self::addThread($current_post);
 		} else {
 			self::updateThread($parent_id);
@@ -1970,7 +1970,7 @@ class Item
 			}
 		}
 
-		if ($item['parent-uri'] === $item['uri']) {
+		if ($item['gravity'] === GRAVITY_PARENT) {
 			self::addShadow($current_post);
 		} else {
 			self::addShadowPost($current_post);

From eebcf1ae86f16bf3022f4c9a7d91d878ed2d2298 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 22:58:34 -0500
Subject: [PATCH 07/18] Separate $parent_item and $toplevel_item in mod/item

---
 mod/item.php | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/mod/item.php b/mod/item.php
index 3869ea910..d70353d9b 100644
--- a/mod/item.php
+++ b/mod/item.php
@@ -100,29 +100,32 @@ function item_post(App $a) {
 	}
 
 	// Is this a reply to something?
-	$toplevel_item_id = intval($_REQUEST['parent'] ?? 0);
+	$parent_item_id = intval($_REQUEST['parent'] ?? 0);
 	$thr_parent_uri = trim($_REQUEST['parent_uri'] ?? '');
 
+	$parent_item = null;
 	$toplevel_item = null;
-	$parent_user = null;
+	$toplevel_item_id = null;
+	$toplevel_user_id = null;
 
 	$objecttype = null;
 	$profile_uid = ($_REQUEST['profile_uid'] ?? 0) ?: local_user();
 	$posttype = ($_REQUEST['post_type'] ?? '') ?: Item::PT_ARTICLE;
 
-	if ($toplevel_item_id || $thr_parent_uri) {
-		if ($toplevel_item_id) {
-			$toplevel_item = Item::selectFirst([], ['id' => $toplevel_item_id]);
+	if ($parent_item_id || $thr_parent_uri) {
+		if ($parent_item_id) {
+			$parent_item = Item::selectFirst([], ['id' => $parent_item_id]);
 		} elseif ($thr_parent_uri) {
-			$toplevel_item = Item::selectFirst([], ['uri' => $thr_parent_uri, 'uid' => $profile_uid]);
+			$parent_item = Item::selectFirst([], ['uri' => $thr_parent_uri, 'uid' => $profile_uid]);
 		}
 
 		// if this isn't the top-level parent of the conversation, find it
-		if (DBA::isResult($toplevel_item)) {
+		if (DBA::isResult($parent_item)) {
 			// The URI and the contact is taken from the direct parent which needn't to be the top parent
-			$thr_parent_uri = $toplevel_item['uri'];
+			$thr_parent_uri = $parent_item['uri'];
+			$toplevel_item = $parent_item;
 
-			if ($toplevel_item['gravity'] != GRAVITY_PARENT) {
+			if ($parent_item['gravity'] != GRAVITY_PARENT) {
 				$toplevel_item = Item::selectFirst([], ['id' => $toplevel_item['parent']]);
 			}
 		}
@@ -146,7 +149,7 @@ function item_post(App $a) {
 		}
 
 		$toplevel_item_id = $toplevel_item['id'];
-		$parent_user = $toplevel_item['uid'];
+		$toplevel_user_id = $toplevel_item['uid'];
 
 		$objecttype = Activity\ObjectType::COMMENT;
 	}
@@ -168,8 +171,8 @@ function item_post(App $a) {
 	}
 
 	// Ensure that the user id in a thread always stay the same
-	if (!is_null($parent_user) && in_array($parent_user, [local_user(), 0])) {
-		$profile_uid = $parent_user;
+	if (!is_null($toplevel_user_id) && in_array($toplevel_user_id, [local_user(), 0])) {
+		$profile_uid = $toplevel_user_id;
 	}
 
 	// Check for multiple posts with the same message id (when the post was created via API)

From d3708cf1c2c819bb3a1711884cbd1b7328fcc4ac Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Wed, 11 Nov 2020 22:59:57 -0500
Subject: [PATCH 08/18] Fix wrong variable use in Model\Item::getTopLevelParent

- It was preventing items at levels 3 and beyond to be inserted
- Logging for missing top level parent has been bumped to notice
---
 src/Model/Item.php | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index a8ac82ede..1ccd85c64 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1496,7 +1496,7 @@ class Item
 		$parent = self::selectFirst($fields, $condition, $params);
 
 		if (!DBA::isResult($parent)) {
-			Logger::info('item parent was not found - ignoring item', ['thr-parent' => $item['thr-parent'], 'uid' => $item['uid']]);
+			Logger::notice('item parent was not found - ignoring item', ['thr-parent' => $item['thr-parent'], 'uid' => $item['uid']]);
 			return [];
 		}
 
@@ -1504,21 +1504,21 @@ class Item
 			return $parent;
 		}
 
-		$condition = ['uri' => $item['parent-uri'],
-			'parent-uri' => $item['parent-uri'],
-			'uid' => $item['uid']];
+		$condition = ['uri' => $parent['parent-uri'],
+			'parent-uri' => $parent['parent-uri'],
+			'uid' => $parent['uid']];
 		// We select wall = 1 in priority for top level permission checks
 		$params = ['order' => ['wall' => true]];
 		$toplevel_parent = self::selectFirst($fields, $condition, $params);
 
 		if (!DBA::isResult($toplevel_parent)) {
-			Logger::info('item parent was not found - ignoring item', ['parent-uri' => $item['parent-uri'], 'uid' => $item['uid']]);
+			Logger::notice('item top level parent was not found - ignoring item', ['parent-uri' => $parent['parent-uri'], 'uid' => $parent['uid']]);
 			return [];
 		}
 
 		if ($toplevel_parent['wall']
-			&& $toplevel_parent['uid'] &&
-			!self::isAllowedByUser($item, $toplevel_parent['uid'])
+			&& $toplevel_parent['uid']
+			&& !self::isAllowedByUser($item, $toplevel_parent['uid'])
 		) {
 			return [];
 		}

From c36ca3cffea2f168683e1c5d2119b23de8028165 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Thu, 12 Nov 2020 09:29:37 -0500
Subject: [PATCH 09/18] Fix null value for item.parent column

---
 mod/item.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mod/item.php b/mod/item.php
index d70353d9b..2e5560f5c 100644
--- a/mod/item.php
+++ b/mod/item.php
@@ -105,7 +105,7 @@ function item_post(App $a) {
 
 	$parent_item = null;
 	$toplevel_item = null;
-	$toplevel_item_id = null;
+	$toplevel_item_id = 0;
 	$toplevel_user_id = null;
 
 	$objecttype = null;

From a9d114316d9ba423cb7440a78e0190e81d2f9625 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Thu, 12 Nov 2020 10:23:50 -0500
Subject: [PATCH 10/18] Ensure the parent field isn't set during Item insertion

- Avoid a database error if a null value is provided
---
 src/Model/Item.php | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index 1ccd85c64..4645f553a 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1734,7 +1734,6 @@ class Item
 			// Update the contact relations
 			Contact\Relation::store($toplevel_parent['author-id'], $item['author-id'], $item['created']);
 
-			unset($item['parent']);
 			unset($item['parent_origin']);
 		} else {
 			$parent_id = 0;
@@ -1777,11 +1776,13 @@ class Item
 			$item['parent'] = $parent_id;
 			Hook::callAll('post_local', $item);
 			unset($item['edit']);
-			unset($item['parent']);
 		} else {
 			Hook::callAll('post_remote', $item);
 		}
 
+		// Set after the insert because top-level posts are self-referencing
+		unset($item['parent']);
+
 		if (!empty($item['cancel'])) {
 			Logger::log('post cancelled by addon.');
 			return 0;

From ff66633a44dbe7d714008e3836a91ae19e63ff3b Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 04:54:01 -0500
Subject: [PATCH 11/18] Remove references to item.parent-uri in Worker\OnePoll

---
 src/Worker/OnePoll.php | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index bdef1ac4d..c5dfb70ab 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -583,9 +583,9 @@ class OnePoll
 							}
 						}
 						$condition = ['uri' => $refs_arr, 'uid' => $importer_uid];
-						$parent = Item::selectFirst(['parent-uri'], $condition);
+						$parent = Item::selectFirst(['uri'], $condition);
 						if (DBA::isResult($parent)) {
-							$datarray['parent-uri'] = $parent['parent-uri'];  // Set the parent as the top-level item
+							$datarray['thr-parent'] = $parent['uri'];
 						}
 					}
 
@@ -613,20 +613,15 @@ class OnePoll
 					$datarray['title'] = self::RemoveReply($datarray['title']);
 
 					// If it seems to be a reply but a header couldn't be found take the last message with matching subject
-					if (empty($datarray['parent-uri']) && $reply) {
+					if (empty($datarray['thr-parent']) && $reply) {
 						$condition = ['title' => $datarray['title'], 'uid' => $importer_uid, 'network' => Protocol::MAIL];
 						$params = ['order' => ['created' => true]];
-						$parent = Item::selectFirst(['parent-uri'], $condition, $params);
+						$parent = Item::selectFirst(['uri'], $condition, $params);
 						if (DBA::isResult($parent)) {
-							$datarray['parent-uri'] = $parent['parent-uri'];
+							$datarray['thr-parent'] = $parent['uri'];
 						}
 					}
 
-					if (!empty($datarray['parent-uri'])) {
-						$datarray['thr-parent'] = $datarray['parent-uri'];
-					}
-					unset($datarray['parent-uri']);
-
 					$headers = imap_headerinfo($mbox, $meta->msgno);
 
 					$object = [];

From 5ce8cc24de5dc184ba5f4250c05d69244454b9fd Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 05:00:31 -0500
Subject: [PATCH 12/18] Clarify parameter type in DFRN::mail

---
 src/Protocol/DFRN.php | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 165a63c7c..7189588a8 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -414,36 +414,36 @@ class DFRN
 	/**
 	 * Create XML text for DFRN mails
 	 *
-	 * @param array $item  message elements
+	 * @param array $mail  Mail record
 	 * @param array $owner Owner record
 	 *
 	 * @return string DFRN mail
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @todo  Find proper type-hints
 	 */
-	public static function mail($item, $owner)
+	public static function mail(array $mail, array $owner)
 	{
 		$doc = new DOMDocument('1.0', 'utf-8');
 		$doc->formatOutput = true;
 
 		$root = self::addHeader($doc, $owner, "dfrn:owner", "", false);
 
-		$mail = $doc->createElement("dfrn:mail");
-		$sender = $doc->createElement("dfrn:sender");
+		$mailElement = $doc->createElement("dfrn:mail");
+		$senderElement = $doc->createElement("dfrn:sender");
 
-		XML::addElement($doc, $sender, "dfrn:name", $owner['name']);
-		XML::addElement($doc, $sender, "dfrn:uri", $owner['url']);
-		XML::addElement($doc, $sender, "dfrn:avatar", $owner['thumb']);
+		XML::addElement($doc, $senderElement, "dfrn:name", $owner['name']);
+		XML::addElement($doc, $senderElement, "dfrn:uri", $owner['url']);
+		XML::addElement($doc, $senderElement, "dfrn:avatar", $owner['thumb']);
 
-		$mail->appendChild($sender);
+		$mailElement->appendChild($senderElement);
 
-		XML::addElement($doc, $mail, "dfrn:id", $item['uri']);
-		XML::addElement($doc, $mail, "dfrn:in-reply-to", $item['thr-parent']);
-		XML::addElement($doc, $mail, "dfrn:sentdate", DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM));
-		XML::addElement($doc, $mail, "dfrn:subject", $item['title']);
-		XML::addElement($doc, $mail, "dfrn:content", $item['body']);
+		XML::addElement($doc, $mailElement, "dfrn:id", $mail['uri']);
+		XML::addElement($doc, $mailElement, "dfrn:in-reply-to", $mail['parent-uri']);
+		XML::addElement($doc, $mailElement, "dfrn:sentdate", DateTimeFormat::utc($mail['created'] . '+00:00', DateTimeFormat::ATOM));
+		XML::addElement($doc, $mailElement, "dfrn:subject", $mail['title']);
+		XML::addElement($doc, $mailElement, "dfrn:content", $mail['body']);
 
-		$root->appendChild($mail);
+		$root->appendChild($mailElement);
 
 		return trim($doc->saveXML());
 	}

From 042f6b98ac1299f63b9c8d58423f2b252e20ed53 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 05:00:52 -0500
Subject: [PATCH 13/18] Remove unnecessary data array assignment in
 Protocol\Feed

---
 src/Protocol/Feed.php | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/Protocol/Feed.php b/src/Protocol/Feed.php
index c7d19a996..93e68241c 100644
--- a/src/Protocol/Feed.php
+++ b/src/Protocol/Feed.php
@@ -354,8 +354,6 @@ class Feed
 
 			$item["plink"] = DI::httpRequest()->finalUrl($item["plink"]);
 
-			$item["thr-parent"] = $item["uri"];
-
 			$item["title"] = XML::getFirstNodeValue($xpath, 'atom:title/text()', $entry);
 
 			if (empty($item["title"])) {

From 2e7c505ac079b0d3b11076e1ad5fb378b03d5453 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 05:01:29 -0500
Subject: [PATCH 14/18] Revert wrong item.thr-parent field usage in
 Protocol\OStatus

---
 src/Protocol/OStatus.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Protocol/OStatus.php b/src/Protocol/OStatus.php
index 9218f2665..9d9e10f7a 100644
--- a/src/Protocol/OStatus.php
+++ b/src/Protocol/OStatus.php
@@ -523,7 +523,7 @@ class OStatus
 					}
 				} else {
 					// But we will only import complete threads
-					$valid = Item::exists(['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['thr-parent']]);
+					$valid = Item::exists(['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['parent-uri']]);
 					if ($valid) {
 						Logger::log("Item with uri ".self::$itemlist[0]["uri"]." belongs to parent ".self::$itemlist[0]['thr-parent']." of user ".$importer["uid"].". It will be imported.", Logger::DEBUG);
 					}

From c98da630413b5c420d624f1895de57b5c15a1be4 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 05:05:52 -0500
Subject: [PATCH 15/18] [Database version 1375] Add update method to populate
 missing item.thr-parent values

---
 static/dbstructure.config.php | 2 +-
 update.php                    | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/static/dbstructure.config.php b/static/dbstructure.config.php
index d1da02412..290550174 100644
--- a/static/dbstructure.config.php
+++ b/static/dbstructure.config.php
@@ -54,7 +54,7 @@
 use Friendica\Database\DBA;
 
 if (!defined('DB_UPDATE_VERSION')) {
-	define('DB_UPDATE_VERSION', 1374);
+	define('DB_UPDATE_VERSION', 1375);
 }
 
 return [
diff --git a/update.php b/update.php
index 37cccd768..460fad885 100644
--- a/update.php
+++ b/update.php
@@ -749,3 +749,12 @@ function pre_update_1365()
 
 	return Update::SUCCESS;
 }
+
+function update_1375()
+{
+	if (!DBA::e("UPDATE `item` SET `thr-parent` = `parent-uri`, `thr-parent-id` = `parent-uri-id` WHERE `thr-parent` = ''")) {
+		return Update::FAILED;
+	}
+
+	return Update::SUCCESS;
+}

From cb963a3259f6cbe20af3eed06223cb4f85169f0d Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Fri, 13 Nov 2020 23:56:19 -0500
Subject: [PATCH 16/18] Retrieve local top level parent item separately to
 check permissions in Model\Item::getTopLevelParentData

---
 src/Model/Item.php | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index 4645f553a..508cb691c 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1507,19 +1507,17 @@ class Item
 		$condition = ['uri' => $parent['parent-uri'],
 			'parent-uri' => $parent['parent-uri'],
 			'uid' => $parent['uid']];
-		// We select wall = 1 in priority for top level permission checks
-		$params = ['order' => ['wall' => true]];
+		$params = ['order' => ['id' => false]];
 		$toplevel_parent = self::selectFirst($fields, $condition, $params);
-
 		if (!DBA::isResult($toplevel_parent)) {
 			Logger::notice('item top level parent was not found - ignoring item', ['parent-uri' => $parent['parent-uri'], 'uid' => $parent['uid']]);
 			return [];
 		}
 
-		if ($toplevel_parent['wall']
-			&& $toplevel_parent['uid']
-			&& !self::isAllowedByUser($item, $toplevel_parent['uid'])
-		) {
+		// If the thread originated from this node, we check the permission against the thread starter
+		$condition = ['uri' => $toplevel_parent['uri'], 'wall' => true];
+		$localTopLevelParent = self::selectFirst(['uid'], $condition);
+		if (!empty($localTopLevelParent['uid']) && !self::isAllowedByUser($item, $localTopLevelParent['uid'])) {
 			return [];
 		}
 

From b5d3fcb8d4ec29d072779480c5afcca1201e5300 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Sat, 14 Nov 2020 07:41:01 -0500
Subject: [PATCH 17/18] Move top-level permission check outside of
 Model\Item::getTopLevelParentData

- It wasn't checked when the direct parent was also the top-level parent
---
 src/Model/Item.php | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Model/Item.php b/src/Model/Item.php
index 508cb691c..fc4d81e43 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1514,13 +1514,6 @@ class Item
 			return [];
 		}
 
-		// If the thread originated from this node, we check the permission against the thread starter
-		$condition = ['uri' => $toplevel_parent['uri'], 'wall' => true];
-		$localTopLevelParent = self::selectFirst(['uid'], $condition);
-		if (!empty($localTopLevelParent['uid']) && !self::isAllowedByUser($item, $localTopLevelParent['uid'])) {
-			return [];
-		}
-
 		return $toplevel_parent;
 	}
 
@@ -1689,6 +1682,13 @@ class Item
 				return 0;
 			}
 
+			// If the thread originated from this node, we check the permission against the thread starter
+			$condition = ['uri' => $toplevel_parent['uri'], 'wall' => true];
+			$localTopLevelParent = self::selectFirst(['uid'], $condition);
+			if (!empty($localTopLevelParent['uid']) && !self::isAllowedByUser($item, $localTopLevelParent['uid'])) {
+				return 0;
+			}
+
 			$parent_id          = $toplevel_parent['id'];
 			$item['parent-uri'] = $toplevel_parent['uri'];
 			$item['deleted']    = $toplevel_parent['deleted'];

From 682b9c24f8e494dd2caaffe72184ab89040b087f Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Sun, 15 Nov 2020 11:42:46 -0500
Subject: [PATCH 18/18] Update database.sql with the latest structure changes

---
 database.sql | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/database.sql b/database.sql
index daf65d7c8..e2a0f243a 100644
--- a/database.sql
+++ b/database.sql
@@ -641,8 +641,8 @@ CREATE TABLE IF NOT EXISTS `item` (
 	`uri-id` int unsigned COMMENT 'Id of the item-uri table entry that contains the item uri',
 	`uri-hash` varchar(80) NOT NULL DEFAULT '' COMMENT 'RIPEMD-128 hash from uri',
 	`parent` int unsigned NOT NULL DEFAULT 0 COMMENT 'item.id of the parent to this item if it is a reply of some form; otherwise this must be set to the id of this item',
-	`parent-uri` varchar(255) NOT NULL DEFAULT '' COMMENT 'uri of the parent to this item',
-	`parent-uri-id` int unsigned COMMENT 'Id of the item-uri table that contains the parent uri',
+	`parent-uri` varchar(255) NOT NULL DEFAULT '' COMMENT 'uri of the top-level parent to this item',
+	`parent-uri-id` int unsigned COMMENT 'Id of the item-uri table that contains the top-level parent uri',
 	`thr-parent` varchar(255) NOT NULL DEFAULT '' COMMENT 'If the parent of this item is not the top-level item in the conversation, the uri of the immediate parent; otherwise set to parent-uri',
 	`thr-parent-id` int unsigned COMMENT 'Id of the item-uri table that contains the thread parent uri',
 	`created` datetime NOT NULL DEFAULT '0001-01-01 00:00:00' COMMENT 'Creation timestamp.',