diff --git a/include/text.php b/include/text.php
index aae7393122..aa4b2c8dba 100644
--- a/include/text.php
+++ b/include/text.php
@@ -24,6 +24,7 @@ use Friendica\Util\Map;
 use Friendica\Util\Proxy as ProxyUtils;
 
 use Friendica\Core\Logger;
+use Friendica\Model\FileTag;
 
 require_once "include/conversation.php";
 
@@ -1099,9 +1100,9 @@ function get_cats_and_terms($item)
 	if ($cnt) {
 		foreach ($matches as $mtch) {
 			$categories[] = [
-				'name' => xmlify(file_tag_decode($mtch[1])),
+				'name' => xmlify(FileTag::decode($mtch[1])),
 				'url' =>  "#",
-				'removeurl' => ((local_user() == $item['uid'])?'filerm/' . $item['id'] . '?f=&cat=' . xmlify(file_tag_decode($mtch[1])):""),
+				'removeurl' => ((local_user() == $item['uid'])?'filerm/' . $item['id'] . '?f=&cat=' . xmlify(FileTag::decode($mtch[1])):""),
 				'first' => $first,
 				'last' => false
 			];
@@ -1120,9 +1121,9 @@ function get_cats_and_terms($item)
 		if ($cnt) {
 			foreach ($matches as $mtch) {
 				$folders[] = [
-					'name' => xmlify(file_tag_decode($mtch[1])),
+					'name' => xmlify(FileTag::decode($mtch[1])),
 					'url' =>  "#",
-					'removeurl' => ((local_user() == $item['uid']) ? 'filerm/' . $item['id'] . '?f=&term=' . xmlify(file_tag_decode($mtch[1])) : ""),
+					'removeurl' => ((local_user() == $item['uid']) ? 'filerm/' . $item['id'] . '?f=&term=' . xmlify(FileTag::decode($mtch[1])) : ""),
 					'first' => $first,
 					'last' => false
 				];
@@ -1360,199 +1361,6 @@ function item_post_type($item) {
 	return L10n::t('post');
 }
 
-// post categories and "save to file" use the same item.file table for storage.
-// We will differentiate the different uses by wrapping categories in angle brackets
-// and save to file categories in square brackets.
-// To do this we need to escape these characters if they appear in our tag.
-
-function file_tag_encode($s) {
-	return str_replace(['<','>','[',']'],['%3c','%3e','%5b','%5d'],$s);
-}
-
-function file_tag_decode($s) {
-	return str_replace(['%3c', '%3e', '%5b', '%5d'], ['<', '>', '[', ']'], $s);
-}
-
-function file_tag_file_query($table,$s,$type = 'file') {
-
-	if ($type == 'file') {
-		$str = preg_quote('[' . str_replace('%', '%%', file_tag_encode($s)) . ']');
-	} else {
-		$str = preg_quote('<' . str_replace('%', '%%', file_tag_encode($s)) . '>');
-	}
-	return " AND " . (($table) ? DBA::escape($table) . '.' : '') . "file regexp '" . DBA::escape($str) . "' ";
-}
-
-// ex. given music,video return <music><video> or [music][video]
-function file_tag_list_to_file($list, $type = 'file') {
-	$tag_list = '';
-	if (strlen($list)) {
-		$list_array = explode(",",$list);
-		if ($type == 'file') {
-			$lbracket = '[';
-			$rbracket = ']';
-		} else {
-			$lbracket = '<';
-			$rbracket = '>';
-		}
-
-		foreach ($list_array as $item) {
-			if (strlen($item)) {
-				$tag_list .= $lbracket . file_tag_encode(trim($item))  . $rbracket;
-			}
-		}
-	}
-	return $tag_list;
-}
-
-// ex. given <music><video>[friends], return music,video or friends
-function file_tag_file_to_list($file, $type = 'file') {
-	$matches = false;
-	$list = '';
-	if ($type == 'file') {
-		$cnt = preg_match_all('/\[(.*?)\]/', $file, $matches, PREG_SET_ORDER);
-	} else {
-		$cnt = preg_match_all('/<(.*?)>/', $file, $matches, PREG_SET_ORDER);
-	}
-	if ($cnt) {
-		foreach ($matches as $mtch) {
-			if (strlen($list)) {
-				$list .= ',';
-			}
-			$list .= file_tag_decode($mtch[1]);
-		}
-	}
-
-	return $list;
-}
-
-function file_tag_update_pconfig($uid, $file_old, $file_new, $type = 'file') {
-	// $file_old - categories previously associated with an item
-	// $file_new - new list of categories for an item
-
-	if (!intval($uid)) {
-		return false;
-	} elseif ($file_old == $file_new) {
-		return true;
-	}
-
-	$saved = PConfig::get($uid, 'system', 'filetags');
-	if (strlen($saved)) {
-		if ($type == 'file') {
-			$lbracket = '[';
-			$rbracket = ']';
-			$termtype = TERM_FILE;
-		} else {
-			$lbracket = '<';
-			$rbracket = '>';
-			$termtype = TERM_CATEGORY;
-		}
-
-		$filetags_updated = $saved;
-
-		// check for new tags to be added as filetags in pconfig
-		$new_tags = [];
-		$check_new_tags = explode(",",file_tag_file_to_list($file_new,$type));
-
-		foreach ($check_new_tags as $tag) {
-			if (!stristr($saved,$lbracket . file_tag_encode($tag) . $rbracket)) {
-				$new_tags[] = $tag;
-			}
-		}
-
-		$filetags_updated .= file_tag_list_to_file(implode(",",$new_tags),$type);
-
-		// check for deleted tags to be removed from filetags in pconfig
-		$deleted_tags = [];
-		$check_deleted_tags = explode(",",file_tag_file_to_list($file_old,$type));
-
-		foreach ($check_deleted_tags as $tag) {
-			if (!stristr($file_new,$lbracket . file_tag_encode($tag) . $rbracket)) {
-				$deleted_tags[] = $tag;
-			}
-		}
-
-		foreach ($deleted_tags as $key => $tag) {
-			$r = q("SELECT `oid` FROM `term` WHERE `term` = '%s' AND `otype` = %d AND `type` = %d AND `uid` = %d",
-				DBA::escape($tag),
-				intval(TERM_OBJ_POST),
-				intval($termtype),
-				intval($uid));
-
-			if (DBA::isResult($r)) {
-				unset($deleted_tags[$key]);
-			} else {
-				$filetags_updated = str_replace($lbracket . file_tag_encode($tag) . $rbracket,'',$filetags_updated);
-			}
-		}
-
-		if ($saved != $filetags_updated) {
-			PConfig::set($uid, 'system', 'filetags', $filetags_updated);
-		}
-		return true;
-	} elseif (strlen($file_new)) {
-		PConfig::set($uid, 'system', 'filetags', $file_new);
-	}
-	return true;
-}
-
-function file_tag_save_file($uid, $item_id, $file)
-{
-	if (!intval($uid)) {
-		return false;
-	}
-
-	$item = Item::selectFirst(['file'], ['id' => $item_id, 'uid' => $uid]);
-	if (DBA::isResult($item)) {
-		if (!stristr($item['file'],'[' . file_tag_encode($file) . ']')) {
-			$fields = ['file' => $item['file'] . '[' . file_tag_encode($file) . ']'];
-			Item::update($fields, ['id' => $item_id]);
-		}
-		$saved = PConfig::get($uid, 'system', 'filetags');
-		if (!strlen($saved) || !stristr($saved, '[' . file_tag_encode($file) . ']')) {
-			PConfig::set($uid, 'system', 'filetags', $saved . '[' . file_tag_encode($file) . ']');
-		}
-		info(L10n::t('Item filed'));
-	}
-	return true;
-}
-
-function file_tag_unsave_file($uid, $item_id, $file, $cat = false)
-{
-	if (!intval($uid)) {
-		return false;
-	}
-
-	if ($cat == true) {
-		$pattern = '<' . file_tag_encode($file) . '>' ;
-		$termtype = TERM_CATEGORY;
-	} else {
-		$pattern = '[' . file_tag_encode($file) . ']' ;
-		$termtype = TERM_FILE;
-	}
-
-	$item = Item::selectFirst(['file'], ['id' => $item_id, 'uid' => $uid]);
-	if (!DBA::isResult($item)) {
-		return false;
-	}
-
-	$fields = ['file' => str_replace($pattern,'',$item['file'])];
-	Item::update($fields, ['id' => $item_id]);
-
-	$r = q("SELECT `oid` FROM `term` WHERE `term` = '%s' AND `otype` = %d AND `type` = %d AND `uid` = %d",
-		DBA::escape($file),
-		intval(TERM_OBJ_POST),
-		intval($termtype),
-		intval($uid)
-	);
-	if (!DBA::isResult($r)) {
-		$saved = PConfig::get($uid, 'system', 'filetags');
-		PConfig::set($uid, 'system', 'filetags', str_replace($pattern, '', $saved));
-	}
-
-	return true;
-}
-
 function normalise_openid($s) {
 	return trim(str_replace(['http://', 'https://'], ['', ''], $s), '/');
 }
diff --git a/src/Model/FileTag.php b/src/Model/FileTag.php
new file mode 100644
index 0000000000..d2937a7312
--- /dev/null
+++ b/src/Model/FileTag.php
@@ -0,0 +1,266 @@
+<?php
+/**
+ * @file src/Model/FileTag.php
+ */
+
+namespace Friendica\Model;
+
+use Friendica\Core\L10n;
+use Friendica\Core\PConfig;
+use Friendica\Database\DBA;
+use Friendica\Model\Item;
+
+/**
+ * @brief This class handles FileTag related functions
+ */
+class FileTag
+{
+    // post categories and "save to file" use the same item.file table for storage.
+    // We will differentiate the different uses by wrapping categories in angle brackets
+    // and save to file categories in square brackets.
+    // To do this we need to escape these characters if they appear in our tag.
+
+    /**
+     * @brief URL encode &lt, &gt, left and right brackets
+     */
+    public static function encode($s)
+    {
+        return str_replace(['<', '>', '[', ']'], ['%3c', '%3e', '%5b', '%5d'], $s);
+    }
+
+    /**
+     * @brief URL decode &lt, &gt, left and right brackets
+     */
+    public static function decode($s)
+    {
+        return str_replace(['%3c', '%3e', '%5b', '%5d'], ['<', '>', '[', ']'], $s);
+    }
+
+    /**
+     * @brief Query files for tag
+     */
+    public static function fileQuery($table, $s, $type = 'file')
+    {
+        if ($type == 'file') {
+            $str = preg_quote('[' . str_replace('%', '%%', self::encode($s)) . ']');
+        } else {
+            $str = preg_quote('<' . str_replace('%', '%%', self::encode($s)) . '>');
+        }
+
+        return " AND " . (($table) ? DBA::escape($table) . '.' : '') . "file regexp '" . DBA::escape($str) . "' ";
+    }
+
+    /**
+     * @brief Get file tags from list
+     * 
+     * ex. given music,video return <music><video> or [music][video]
+     */
+    public static function listToFile($list, $type = 'file')
+    {
+        $tag_list = '';
+        if (strlen($list)) {
+            $list_array = explode(",", $list);
+            if ($type == 'file') {
+                $lbracket = '[';
+                $rbracket = ']';
+            } else {
+                $lbracket = '<';
+                $rbracket = '>';
+            }
+
+            foreach ($list_array as $item)
+            {
+                if (strlen($item))
+                {
+                    $tag_list .= $lbracket . self::encode(trim($item))  . $rbracket;
+                }
+            }
+        }
+
+        return $tag_list;
+    }
+
+    /**
+     * @brief Get list from file tags
+     * 
+     * ex. given <music><video>[friends], return music,video or friends
+     */
+    public static function fileToList($file, $type = 'file')
+    {
+        $matches = false;
+        $list = '';
+        if ($type == 'file') {
+            $cnt = preg_match_all('/\[(.*?)\]/', $file, $matches, PREG_SET_ORDER);
+        } else {
+            $cnt = preg_match_all('/<(.*?)>/', $file, $matches, PREG_SET_ORDER);
+        }
+        if ($cnt) {
+            foreach ($matches as $mtch) {
+                if (strlen($list)) {
+                    $list .= ',';
+                }
+                $list .= self::decode($mtch[1]);
+            }
+        }
+
+        return $list;
+    }
+
+    /**
+     * @brief Update file tags in PConfig
+     */
+    public static function updatePconfig($uid, $file_old, $file_new, $type = 'file')
+    {
+        // $file_old - categories previously associated with an item
+        // $file_new - new list of categories for an item
+
+        if (!intval($uid)) {
+            return false;
+        } elseif ($file_old == $file_new) {
+            return true;
+        }
+
+        $saved = PConfig::get($uid, 'system', 'filetags');
+
+        if (strlen($saved))
+        {
+            if ($type == 'file') {
+                $lbracket = '[';
+                $rbracket = ']';
+                $termtype = TERM_FILE;
+            } else {
+                $lbracket = '<';
+                $rbracket = '>';
+                $termtype = TERM_CATEGORY;
+            }
+
+            $filetags_updated = $saved;
+
+            // check for new tags to be added as filetags in pconfig
+            $new_tags = [];
+            $check_new_tags = explode(",", self::fileToList($file_new, $type));
+
+            foreach ($check_new_tags as $tag)
+            {
+                if (!stristr($saved,$lbracket . self::encode($tag) . $rbracket)) {
+                    $new_tags[] = $tag;
+                }
+            }
+
+            $filetags_updated .= self::listToFile(implode(",", $new_tags), $type);
+
+            // check for deleted tags to be removed from filetags in pconfig
+            $deleted_tags = [];
+            $check_deleted_tags = explode(",", self::fileToList($file_old, $type));
+
+            foreach ($check_deleted_tags as $tag)
+            {
+                if (!stristr($file_new,$lbracket . self::encode($tag) . $rbracket)) {
+                    $deleted_tags[] = $tag;
+                }
+            }
+
+            foreach ($deleted_tags as $key => $tag)
+            {
+                $r = q("SELECT `oid` FROM `term` WHERE `term` = '%s' AND `otype` = %d AND `type` = %d AND `uid` = %d",
+                    DBA::escape($tag),
+                    intval(TERM_OBJ_POST),
+                    intval($termtype),
+                    intval($uid));
+
+                if (DBA::isResult($r)) {
+                    unset($deleted_tags[$key]);
+                } else {
+                    $filetags_updated = str_replace($lbracket . self::encode($tag) . $rbracket, '', $filetags_updated);
+                }
+            }
+
+            if ($saved != $filetags_updated)
+            {
+                PConfig::set($uid, 'system', 'filetags', $filetags_updated);
+            }
+
+            return true;
+        } elseif (strlen($file_new)) {
+            PConfig::set($uid, 'system', 'filetags', $file_new);
+        }
+
+        return true;
+    }
+
+    /**
+     * @brief Add tag to file
+     */
+    public static function saveFile($uid, $item_id, $file)
+    {
+        if (!intval($uid))
+        {
+            return false;
+        }
+
+        $item = Item::selectFirst(['file'], ['id' => $item_id, 'uid' => $uid]);
+        if (DBA::isResult($item))
+        {
+            if (!stristr($item['file'], '[' . self::encode($file) . ']'))
+            {
+                $fields = ['file' => $item['file'] . '[' . self::encode($file) . ']'];
+                Item::update($fields, ['id' => $item_id]);
+            }
+
+            $saved = PConfig::get($uid, 'system', 'filetags');
+
+            if (!strlen($saved) || !stristr($saved, '[' . self::encode($file) . ']'))
+            {
+                PConfig::set($uid, 'system', 'filetags', $saved . '[' . self::encode($file) . ']');
+            }
+
+            info(L10n::t('Item filed'));
+        }
+
+        return true;
+    }
+
+    /**
+     * @brief Remove tag from file
+     */
+    public static function unsaveFile($uid, $item_id, $file, $cat = false)
+    {
+        if (!intval($uid))
+        {
+            return false;
+        }
+
+        if ($cat == true) {
+            $pattern = '<' . self::encode($file) . '>' ;
+            $termtype = TERM_CATEGORY;
+        } else {
+            $pattern = '[' . self::encode($file) . ']' ;
+            $termtype = TERM_FILE;
+        }
+
+        $item = Item::selectFirst(['file'], ['id' => $item_id, 'uid' => $uid]);
+
+        if (!DBA::isResult($item))
+        {
+            return false;
+        }
+
+        $fields = ['file' => str_replace($pattern, '', $item['file'])];
+        Item::update($fields, ['id' => $item_id]);
+
+        $r = q("SELECT `oid` FROM `term` WHERE `term` = '%s' AND `otype` = %d AND `type` = %d AND `uid` = %d",
+            DBA::escape($file),
+            intval(TERM_OBJ_POST),
+            intval($termtype),
+            intval($uid)
+        );
+
+        if (!DBA::isResult($r))
+        {
+            $saved = PConfig::get($uid, 'system', 'filetags');
+            PConfig::set($uid, 'system', 'filetags', str_replace($pattern, '', $saved));
+        }
+
+        return true;
+    }
+}