Introduce Bookmark object and Service layer to retrieve them

See https://github.com/shaarli/Shaarli/issues/1307 for details

3 files changed, 1648 insertions, 0 deletions

diff --git a/application/legacy/LegacyLinkDB.php b/application/legacy/LegacyLinkDB.php
new file mode 100644
index 00000000..7ccf5e54
--- /dev/null
+++ b/application/legacy/LegacyLinkDB.php
@@ -0,0 +1,580 @@
+<?php
+
+namespace Shaarli\Legacy;
+
+use ArrayAccess;
+use Countable;
+use DateTime;
+use Iterator;
+use Shaarli\Bookmark\Exception\BookmarkNotFoundException;
+use Shaarli\Exceptions\IOException;
+use Shaarli\FileUtils;
+
+/**
+ * Data storage for bookmarks.
+ *
+ * This object behaves like an associative array.
+ *
+ * Example:
+ *    $myLinks = new LinkDB();
+ *    echo $myLinks[350]['title'];
+ *    foreach ($myLinks as $link)
+ *       echo $link['title'].' at url '.$link['url'].'; description:'.$link['description'];
+ *
+ * Available keys:
+ *  - id:       primary key, incremental integer identifier (persistent)
+ *  - description: description of the entry
+ *  - created:  creation date of this entry, DateTime object.
+ *  - updated:  last modification date of this entry, DateTime object.
+ *  - private:  Is this link private? 0=no, other value=yes
+ *  - tags:     tags attached to this entry (separated by spaces)
+ *  - title     Title of the link
+ *  - url       URL of the link. Used for displayable bookmarks.
+ *              Can be absolute or relative in the database but the relative bookmarks
+ *              will be converted to absolute ones in templates.
+ *  - real_url  Raw URL in stored in the DB (absolute or relative).
+ *  - shorturl  Permalink smallhash
+ *
+ * Implements 3 interfaces:
+ *  - ArrayAccess: behaves like an associative array;
+ *  - Countable:   there is a count() method;
+ *  - Iterator:    usable in foreach () loops.
+ *
+ * ID mechanism:
+ *   ArrayAccess is implemented in a way that will allow to access a link
+ *   with the unique identifier ID directly with $link[ID].
+ *   Note that it's not the real key of the link array attribute.
+ *   This mechanism is in place to have persistent link IDs,
+ *   even though the internal array is reordered by date.
+ *   Example:
+ *     - DB: link #1 (2010-01-01) link #2 (2016-01-01)
+ *     - Order: #2 #1
+ *     - Import bookmarks containing: link #3 (2013-01-01)
+ *     - New DB: link #1 (2010-01-01) link #2 (2016-01-01) link #3 (2013-01-01)
+ *     - Real order: #2 #3 #1
+ *
+ * @deprecated
+ */
+class LegacyLinkDB implements Iterator, Countable, ArrayAccess
+{
+    // Links are stored as a PHP serialized string
+    private $datastore;
+
+    // Link date storage format
+    const LINK_DATE_FORMAT = 'Ymd_His';
+
+    // List of bookmarks (associative array)
+    //  - key:   link date (e.g. "20110823_124546"),
+    //  - value: associative array (keys: title, description...)
+    private $links;
+
+    // List of all recorded URLs (key=url, value=link offset)
+    // for fast reserve search (url-->link offset)
+    private $urls;
+
+    /**
+     * @var array List of all bookmarks IDS mapped with their array offset.
+     *            Map: id->offset.
+     */
+    protected $ids;
+
+    // List of offset keys (for the Iterator interface implementation)
+    private $keys;
+
+    // Position in the $this->keys array (for the Iterator interface)
+    private $position;
+
+    // Is the user logged in? (used to filter private bookmarks)
+    private $loggedIn;
+
+    // Hide public bookmarks
+    private $hidePublicLinks;
+
+    /**
+     * Creates a new LinkDB
+     *
+     * Checks if the datastore exists; else, attempts to create a dummy one.
+     *
+     * @param string  $datastore        datastore file path.
+     * @param boolean $isLoggedIn       is the user logged in?
+     * @param boolean $hidePublicLinks  if true all bookmarks are private.
+     */
+    public function __construct(
+        $datastore,
+        $isLoggedIn,
+        $hidePublicLinks
+    ) {
+
+        $this->datastore = $datastore;
+        $this->loggedIn = $isLoggedIn;
+        $this->hidePublicLinks = $hidePublicLinks;
+        $this->check();
+        $this->read();
+    }
+
+    /**
+     * Countable - Counts elements of an object
+     */
+    public function count()
+    {
+        return count($this->links);
+    }
+
+    /**
+     * ArrayAccess - Assigns a value to the specified offset
+     */
+    public function offsetSet($offset, $value)
+    {
+        // TODO: use exceptions instead of "die"
+        if (!$this->loggedIn) {
+            die(t('You are not authorized to add a link.'));
+        }
+        if (!isset($value['id']) || empty($value['url'])) {
+            die(t('Internal Error: A link should always have an id and URL.'));
+        }
+        if (($offset !== null && !is_int($offset)) || !is_int($value['id'])) {
+            die(t('You must specify an integer as a key.'));
+        }
+        if ($offset !== null && $offset !== $value['id']) {
+            die(t('Array offset and link ID must be equal.'));
+        }
+
+        // If the link exists, we reuse the real offset, otherwise new entry
+        $existing = $this->getLinkOffset($offset);
+        if ($existing !== null) {
+            $offset = $existing;
+        } else {
+            $offset = count($this->links);
+        }
+        $this->links[$offset] = $value;
+        $this->urls[$value['url']] = $offset;
+        $this->ids[$value['id']] = $offset;
+    }
+
+    /**
+     * ArrayAccess - Whether or not an offset exists
+     */
+    public function offsetExists($offset)
+    {
+        return array_key_exists($this->getLinkOffset($offset), $this->links);
+    }
+
+    /**
+     * ArrayAccess - Unsets an offset
+     */
+    public function offsetUnset($offset)
+    {
+        if (!$this->loggedIn) {
+            // TODO: raise an exception
+            die('You are not authorized to delete a link.');
+        }
+        $realOffset = $this->getLinkOffset($offset);
+        $url = $this->links[$realOffset]['url'];
+        unset($this->urls[$url]);
+        unset($this->ids[$realOffset]);
+        unset($this->links[$realOffset]);
+    }
+
+    /**
+     * ArrayAccess - Returns the value at specified offset
+     */
+    public function offsetGet($offset)
+    {
+        $realOffset = $this->getLinkOffset($offset);
+        return isset($this->links[$realOffset]) ? $this->links[$realOffset] : null;
+    }
+
+    /**
+     * Iterator - Returns the current element
+     */
+    public function current()
+    {
+        return $this[$this->keys[$this->position]];
+    }
+
+    /**
+     * Iterator - Returns the key of the current element
+     */
+    public function key()
+    {
+        return $this->keys[$this->position];
+    }
+
+    /**
+     * Iterator - Moves forward to next element
+     */
+    public function next()
+    {
+        ++$this->position;
+    }
+
+    /**
+     * Iterator - Rewinds the Iterator to the first element
+     *
+     * Entries are sorted by date (latest first)
+     */
+    public function rewind()
+    {
+        $this->keys = array_keys($this->ids);
+        $this->position = 0;
+    }
+
+    /**
+     * Iterator - Checks if current position is valid
+     */
+    public function valid()
+    {
+        return isset($this->keys[$this->position]);
+    }
+
+    /**
+     * Checks if the DB directory and file exist
+     *
+     * If no DB file is found, creates a dummy DB.
+     */
+    private function check()
+    {
+        if (file_exists($this->datastore)) {
+            return;
+        }
+
+        // Create a dummy database for example
+        $this->links = array();
+        $link = array(
+            'id' => 1,
+            'title' => t('The personal, minimalist, super-fast, database free, bookmarking service'),
+            'url' => 'https://shaarli.readthedocs.io',
+            'description' => t(
+                'Welcome to Shaarli! This is your first public bookmark. '
+                . 'To edit or delete me, you must first login.
+
+To learn how to use Shaarli, consult the link "Documentation" at the bottom of this page.
+
+You use the community supported version of the original Shaarli project, by Sebastien Sauvage.'
+            ),
+            'private' => 0,
+            'created' => new DateTime(),
+            'tags' => 'opensource software',
+            'sticky' => false,
+        );
+        $link['shorturl'] = link_small_hash($link['created'], $link['id']);
+        $this->links[1] = $link;
+
+        $link = array(
+            'id' => 0,
+            'title' => t('My secret stuff... - Pastebin.com'),
+            'url' => 'http://sebsauvage.net/paste/?8434b27936c09649#bR7XsXhoTiLcqCpQbmOpBi3rq2zzQUC5hBI7ZT1O3x8=',
+            'description' => t('Shhhh! I\'m a private link only YOU can see. You can delete me too.'),
+            'private' => 1,
+            'created' => new DateTime('1 minute ago'),
+            'tags' => 'secretstuff',
+            'sticky' => false,
+        );
+        $link['shorturl'] = link_small_hash($link['created'], $link['id']);
+        $this->links[0] = $link;
+
+        // Write database to disk
+        $this->write();
+    }
+
+    /**
+     * Reads database from disk to memory
+     */
+    private function read()
+    {
+        // Public bookmarks are hidden and user not logged in => nothing to show
+        if ($this->hidePublicLinks && !$this->loggedIn) {
+            $this->links = array();
+            return;
+        }
+
+        $this->urls = [];
+        $this->ids = [];
+        $this->links = FileUtils::readFlatDB($this->datastore, []);
+
+        $toremove = array();
+        foreach ($this->links as $key => &$link) {
+            if (!$this->loggedIn && $link['private'] != 0) {
+                // Transition for not upgraded databases.
+                unset($this->links[$key]);
+                continue;
+            }
+
+            // Sanitize data fields.
+            sanitizeLink($link);
+
+            // Remove private tags if the user is not logged in.
+            if (!$this->loggedIn) {
+                $link['tags'] = preg_replace('/(^|\s+)\.[^($|\s)]+\s*/', ' ', $link['tags']);
+            }
+
+            $link['real_url'] = $link['url'];
+
+            $link['sticky'] = isset($link['sticky']) ? $link['sticky'] : false;
+
+            // To be able to load bookmarks before running the update, and prepare the update
+            if (!isset($link['created'])) {
+                $link['id'] = $link['linkdate'];
+                $link['created'] = DateTime::createFromFormat(self::LINK_DATE_FORMAT, $link['linkdate']);
+                if (!empty($link['updated'])) {
+                    $link['updated'] = DateTime::createFromFormat(self::LINK_DATE_FORMAT, $link['updated']);
+                }
+                $link['shorturl'] = smallHash($link['linkdate']);
+            }
+
+            $this->urls[$link['url']] = $key;
+            $this->ids[$link['id']] = $key;
+        }
+    }
+
+    /**
+     * Saves the database from memory to disk
+     *
+     * @throws IOException the datastore is not writable
+     */
+    private function write()
+    {
+        $this->reorder();
+        FileUtils::writeFlatDB($this->datastore, $this->links);
+    }
+
+    /**
+     * Saves the database from memory to disk
+     *
+     * @param string $pageCacheDir page cache directory
+     */
+    public function save($pageCacheDir)
+    {
+        if (!$this->loggedIn) {
+            // TODO: raise an Exception instead
+            die('You are not authorized to change the database.');
+        }
+
+        $this->write();
+
+        invalidateCaches($pageCacheDir);
+    }
+
+    /**
+     * Returns the link for a given URL, or False if it does not exist.
+     *
+     * @param string $url URL to search for
+     *
+     * @return mixed the existing link if it exists, else 'false'
+     */
+    public function getLinkFromUrl($url)
+    {
+        if (isset($this->urls[$url])) {
+            return $this->links[$this->urls[$url]];
+        }
+        return false;
+    }
+
+    /**
+     * Returns the shaare corresponding to a smallHash.
+     *
+     * @param string $request QUERY_STRING server parameter.
+     *
+     * @return array $filtered array containing permalink data.
+     *
+     * @throws BookmarkNotFoundException if the smallhash is malformed or doesn't match any link.
+     */
+    public function filterHash($request)
+    {
+        $request = substr($request, 0, 6);
+        $linkFilter = new LegacyLinkFilter($this->links);
+        return $linkFilter->filter(LegacyLinkFilter::$FILTER_HASH, $request);
+    }
+
+    /**
+     * Returns the list of articles for a given day.
+     *
+     * @param string $request day to filter. Format: YYYYMMDD.
+     *
+     * @return array list of shaare found.
+     */
+    public function filterDay($request)
+    {
+        $linkFilter = new LegacyLinkFilter($this->links);
+        return $linkFilter->filter(LegacyLinkFilter::$FILTER_DAY, $request);
+    }
+
+    /**
+     * Filter bookmarks according to search parameters.
+     *
+     * @param array  $filterRequest  Search request content. Supported keys:
+     *                                - searchtags: list of tags
+     *                                - searchterm: term search
+     * @param bool   $casesensitive  Optional: Perform case sensitive filter
+     * @param string $visibility     return only all/private/public bookmarks
+     * @param bool   $untaggedonly   return only untagged bookmarks
+     *
+     * @return array filtered bookmarks, all bookmarks if no suitable filter was provided.
+     */
+    public function filterSearch(
+        $filterRequest = array(),
+        $casesensitive = false,
+        $visibility = 'all',
+        $untaggedonly = false
+    ) {
+
+        // Filter link database according to parameters.
+        $searchtags = isset($filterRequest['searchtags']) ? escape($filterRequest['searchtags']) : '';
+        $searchterm = isset($filterRequest['searchterm']) ? escape($filterRequest['searchterm']) : '';
+
+        // Search tags + fullsearch - blank string parameter will return all bookmarks.
+        $type = LegacyLinkFilter::$FILTER_TAG | LegacyLinkFilter::$FILTER_TEXT; // == "vuotext"
+        $request = [$searchtags, $searchterm];
+
+        $linkFilter = new LegacyLinkFilter($this);
+        return $linkFilter->filter($type, $request, $casesensitive, $visibility, $untaggedonly);
+    }
+
+    /**
+     * Returns the list tags appearing in the bookmarks with the given tags
+     *
+     * @param array  $filteringTags tags selecting the bookmarks to consider
+     * @param string $visibility    process only all/private/public bookmarks
+     *
+     * @return array tag => linksCount
+     */
+    public function linksCountPerTag($filteringTags = [], $visibility = 'all')
+    {
+        $links = $this->filterSearch(['searchtags' => $filteringTags], false, $visibility);
+        $tags = [];
+        $caseMapping = [];
+        foreach ($links as $link) {
+            foreach (preg_split('/\s+/', $link['tags'], 0, PREG_SPLIT_NO_EMPTY) as $tag) {
+                if (empty($tag)) {
+                    continue;
+                }
+                // The first case found will be displayed.
+                if (!isset($caseMapping[strtolower($tag)])) {
+                    $caseMapping[strtolower($tag)] = $tag;
+                    $tags[$caseMapping[strtolower($tag)]] = 0;
+                }
+                $tags[$caseMapping[strtolower($tag)]]++;
+            }
+        }
+
+        /*
+         * Formerly used arsort(), which doesn't define the sort behaviour for equal values.
+         * Also, this function doesn't produce the same result between PHP 5.6 and 7.
+         *
+         * So we now use array_multisort() to sort tags by DESC occurrences,
+         * then ASC alphabetically for equal values.
+         *
+         * @see https://github.com/shaarli/Shaarli/issues/1142
+         */
+        $keys = array_keys($tags);
+        $tmpTags = array_combine($keys, $keys);
+        array_multisort($tags, SORT_DESC, $tmpTags, SORT_ASC, $tags);
+        return $tags;
+    }
+
+    /**
+     * Rename or delete a tag across all bookmarks.
+     *
+     * @param string $from Tag to rename
+     * @param string $to   New tag. If none is provided, the from tag will be deleted
+     *
+     * @return array|bool List of altered bookmarks or false on error
+     */
+    public function renameTag($from, $to)
+    {
+        if (empty($from)) {
+            return false;
+        }
+        $delete = empty($to);
+        // True for case-sensitive tag search.
+        $linksToAlter = $this->filterSearch(['searchtags' => $from], true);
+        foreach ($linksToAlter as $key => &$value) {
+            $tags = preg_split('/\s+/', trim($value['tags']));
+            if (($pos = array_search($from, $tags)) !== false) {
+                if ($delete) {
+                    unset($tags[$pos]); // Remove tag.
+                } else {
+                    $tags[$pos] = trim($to);
+                }
+                $value['tags'] = trim(implode(' ', array_unique($tags)));
+                $this[$value['id']] = $value;
+            }
+        }
+
+        return $linksToAlter;
+    }
+
+    /**
+     * Returns the list of days containing articles (oldest first)
+     * Output: An array containing days (in format YYYYMMDD).
+     */
+    public function days()
+    {
+        $linkDays = array();
+        foreach ($this->links as $link) {
+            $linkDays[$link['created']->format('Ymd')] = 0;
+        }
+        $linkDays = array_keys($linkDays);
+        sort($linkDays);
+
+        return $linkDays;
+    }
+
+    /**
+     * Reorder bookmarks by creation date (newest first).
+     *
+     * Also update the urls and ids mapping arrays.
+     *
+     * @param string $order ASC|DESC
+     */
+    public function reorder($order = 'DESC')
+    {
+        $order = $order === 'ASC' ? -1 : 1;
+        // Reorder array by dates.
+        usort($this->links, function ($a, $b) use ($order) {
+            if (isset($a['sticky']) && isset($b['sticky']) && $a['sticky'] !== $b['sticky']) {
+                return $a['sticky'] ? -1 : 1;
+            }
+            if ($a['created'] == $b['created']) {
+                return $a['id'] < $b['id'] ? 1 * $order : -1 * $order;
+            }
+            return $a['created'] < $b['created'] ? 1 * $order : -1 * $order;
+        });
+
+        $this->urls = [];
+        $this->ids = [];
+        foreach ($this->links as $key => $link) {
+            $this->urls[$link['url']] = $key;
+            $this->ids[$link['id']] = $key;
+        }
+    }
+
+    /**
+     * Return the next key for link creation.
+     * E.g. If the last ID is 597, the next will be 598.
+     *
+     * @return int next ID.
+     */
+    public function getNextId()
+    {
+        if (!empty($this->ids)) {
+            return max(array_keys($this->ids)) + 1;
+        }
+        return 0;
+    }
+
+    /**
+     * Returns a link offset in bookmarks array from its unique ID.
+     *
+     * @param int $id Persistent ID of a link.
+     *
+     * @return int Real offset in local array, or null if doesn't exist.
+     */
+    protected function getLinkOffset($id)
+    {
+        if (isset($this->ids[$id])) {
+            return $this->ids[$id];
+        }
+        return null;
+    }
+}
diff --git a/application/legacy/LegacyLinkFilter.php b/application/legacy/LegacyLinkFilter.php
new file mode 100644
index 00000000..7cf93d60
--- /dev/null
+++ b/application/legacy/LegacyLinkFilter.php
@@ -0,0 +1,451 @@
+<?php
+
+namespace Shaarli\Legacy;
+
+use Exception;
+use Shaarli\Bookmark\Exception\BookmarkNotFoundException;
+
+/**
+ * Class LinkFilter.
+ *
+ * Perform search and filter operation on link data list.
+ *
+ * @deprecated
+ */
+class LegacyLinkFilter
+{
+    /**
+     * @var string permalinks.
+     */
+    public static $FILTER_HASH = 'permalink';
+
+    /**
+     * @var string text search.
+     */
+    public static $FILTER_TEXT = 'fulltext';
+
+    /**
+     * @var string tag filter.
+     */
+    public static $FILTER_TAG = 'tags';
+
+    /**
+     * @var string filter by day.
+     */
+    public static $FILTER_DAY = 'FILTER_DAY';
+
+    /**
+     * @var string Allowed characters for hashtags (regex syntax).
+     */
+    public static $HASHTAG_CHARS = '\p{Pc}\p{N}\p{L}\p{Mn}';
+
+    /**
+     * @var LegacyLinkDB all available links.
+     */
+    private $links;
+
+    /**
+     * @param LegacyLinkDB $links initialization.
+     */
+    public function __construct($links)
+    {
+        $this->links = $links;
+    }
+
+    /**
+     * Filter links according to parameters.
+     *
+     * @param string $type          Type of filter (eg. tags, permalink, etc.).
+     * @param mixed  $request       Filter content.
+     * @param bool   $casesensitive Optional: Perform case sensitive filter if true.
+     * @param string $visibility    Optional: return only all/private/public links
+     * @param string $untaggedonly  Optional: return only untagged links. Applies only if $type includes FILTER_TAG
+     *
+     * @return array filtered link list.
+     */
+    public function filter($type, $request, $casesensitive = false, $visibility = 'all', $untaggedonly = false)
+    {
+        if (!in_array($visibility, ['all', 'public', 'private'])) {
+            $visibility = 'all';
+        }
+
+        switch ($type) {
+            case self::$FILTER_HASH:
+                return $this->filterSmallHash($request);
+            case self::$FILTER_TAG | self::$FILTER_TEXT: // == "vuotext"
+                $noRequest = empty($request) || (empty($request[0]) && empty($request[1]));
+                if ($noRequest) {
+                    if ($untaggedonly) {
+                        return $this->filterUntagged($visibility);
+                    }
+                    return $this->noFilter($visibility);
+                }
+                if ($untaggedonly) {
+                    $filtered = $this->filterUntagged($visibility);
+                } else {
+                    $filtered = $this->links;
+                }
+                if (!empty($request[0])) {
+                    $filtered = (new LegacyLinkFilter($filtered))->filterTags($request[0], $casesensitive, $visibility);
+                }
+                if (!empty($request[1])) {
+                    $filtered = (new LegacyLinkFilter($filtered))->filterFulltext($request[1], $visibility);
+                }
+                return $filtered;
+            case self::$FILTER_TEXT:
+                return $this->filterFulltext($request, $visibility);
+            case self::$FILTER_TAG:
+                if ($untaggedonly) {
+                    return $this->filterUntagged($visibility);
+                } else {
+                    return $this->filterTags($request, $casesensitive, $visibility);
+                }
+            case self::$FILTER_DAY:
+                return $this->filterDay($request);
+            default:
+                return $this->noFilter($visibility);
+        }
+    }
+
+    /**
+     * Unknown filter, but handle private only.
+     *
+     * @param string $visibility Optional: return only all/private/public links
+     *
+     * @return array filtered links.
+     */
+    private function noFilter($visibility = 'all')
+    {
+        if ($visibility === 'all') {
+            return $this->links;
+        }
+
+        $out = array();
+        foreach ($this->links as $key => $value) {
+            if ($value['private'] && $visibility === 'private') {
+                $out[$key] = $value;
+            } elseif (!$value['private'] && $visibility === 'public') {
+                $out[$key] = $value;
+            }
+        }
+
+        return $out;
+    }
+
+    /**
+     * Returns the shaare corresponding to a smallHash.
+     *
+     * @param string $smallHash permalink hash.
+     *
+     * @return array $filtered array containing permalink data.
+     *
+     * @throws BookmarkNotFoundException if the smallhash doesn't match any link.
+     */
+    private function filterSmallHash($smallHash)
+    {
+        $filtered = array();
+        foreach ($this->links as $key => $l) {
+            if ($smallHash == $l['shorturl']) {
+                // Yes, this is ugly and slow
+                $filtered[$key] = $l;
+                return $filtered;
+            }
+        }
+
+        if (empty($filtered)) {
+            throw new BookmarkNotFoundException();
+        }
+
+        return $filtered;
+    }
+
+    /**
+     * Returns the list of links corresponding to a full-text search
+     *
+     * Searches:
+     *  - in the URLs, title and description;
+     *  - are case-insensitive;
+     *  - terms surrounded by quotes " are exact terms search.
+     *  - terms starting with a dash - are excluded (except exact terms).
+     *
+     * Example:
+     *    print_r($mydb->filterFulltext('hollandais'));
+     *
+     * mb_convert_case($val, MB_CASE_LOWER, 'UTF-8')
+     *  - allows to perform searches on Unicode text
+     *  - see https://github.com/shaarli/Shaarli/issues/75 for examples
+     *
+     * @param string $searchterms search query.
+     * @param string $visibility  Optional: return only all/private/public links.
+     *
+     * @return array search results.
+     */
+    private function filterFulltext($searchterms, $visibility = 'all')
+    {
+        if (empty($searchterms)) {
+            return $this->noFilter($visibility);
+        }
+
+        $filtered = array();
+        $search = mb_convert_case(html_entity_decode($searchterms), MB_CASE_LOWER, 'UTF-8');
+        $exactRegex = '/"([^"]+)"/';
+        // Retrieve exact search terms.
+        preg_match_all($exactRegex, $search, $exactSearch);
+        $exactSearch = array_values(array_filter($exactSearch[1]));
+
+        // Remove exact search terms to get AND terms search.
+        $explodedSearchAnd = explode(' ', trim(preg_replace($exactRegex, '', $search)));
+        $explodedSearchAnd = array_values(array_filter($explodedSearchAnd));
+
+        // Filter excluding terms and update andSearch.
+        $excludeSearch = array();
+        $andSearch = array();
+        foreach ($explodedSearchAnd as $needle) {
+            if ($needle[0] == '-' && strlen($needle) > 1) {
+                $excludeSearch[] = substr($needle, 1);
+            } else {
+                $andSearch[] = $needle;
+            }
+        }
+
+        $keys = array('title', 'description', 'url', 'tags');
+
+        // Iterate over every stored link.
+        foreach ($this->links as $id => $link) {
+            // ignore non private links when 'privatonly' is on.
+            if ($visibility !== 'all') {
+                if (!$link['private'] && $visibility === 'private') {
+                    continue;
+                } elseif ($link['private'] && $visibility === 'public') {
+                    continue;
+                }
+            }
+
+            // Concatenate link fields to search across fields.
+            // Adds a '\' separator for exact search terms.
+            $content = '';
+            foreach ($keys as $key) {
+                $content .= mb_convert_case($link[$key], MB_CASE_LOWER, 'UTF-8') . '\\';
+            }
+
+            // Be optimistic
+            $found = true;
+
+            // First, we look for exact term search
+            for ($i = 0; $i < count($exactSearch) && $found; $i++) {
+                $found = strpos($content, $exactSearch[$i]) !== false;
+            }
+
+            // Iterate over keywords, if keyword is not found,
+            // no need to check for the others. We want all or nothing.
+            for ($i = 0; $i < count($andSearch) && $found; $i++) {
+                $found = strpos($content, $andSearch[$i]) !== false;
+            }
+
+            // Exclude terms.
+            for ($i = 0; $i < count($excludeSearch) && $found; $i++) {
+                $found = strpos($content, $excludeSearch[$i]) === false;
+            }
+
+            if ($found) {
+                $filtered[$id] = $link;
+            }
+        }
+
+        return $filtered;
+    }
+
+    /**
+     * generate a regex fragment out of a tag
+     *
+     * @param string $tag to to generate regexs from. may start with '-' to negate, contain '*' as wildcard
+     *
+     * @return string generated regex fragment
+     */
+    private static function tag2regex($tag)
+    {
+        $len = strlen($tag);
+        if (!$len || $tag === "-" || $tag === "*") {
+            // nothing to search, return empty regex
+            return '';
+        }
+        if ($tag[0] === "-") {
+            // query is negated
+            $i = 1; // use offset to start after '-' character
+            $regex = '(?!'; // create negative lookahead
+        } else {
+            $i = 0; // start at first character
+            $regex = '(?='; // use positive lookahead
+        }
+        $regex .= '.*(?:^| )'; // before tag may only be a space or the beginning
+        // iterate over string, separating it into placeholder and content
+        for (; $i < $len; $i++) {
+            if ($tag[$i] === '*') {
+                // placeholder found
+                $regex .= '[^ ]*?';
+            } else {
+                // regular characters
+                $offset = strpos($tag, '*', $i);
+                if ($offset === false) {
+                    // no placeholder found, set offset to end of string
+                    $offset = $len;
+                }
+                // subtract one, as we want to get before the placeholder or end of string
+                $offset -= 1;
+                // we got a tag name that we want to search for. escape any regex characters to prevent conflicts.
+                $regex .= preg_quote(substr($tag, $i, $offset - $i + 1), '/');
+                // move $i on
+                $i = $offset;
+            }
+        }
+        $regex .= '(?:$| ))'; // after the tag may only be a space or the end
+        return $regex;
+    }
+
+    /**
+     * Returns the list of links associated with a given list of tags
+     *
+     * You can specify one or more tags, separated by space or a comma, e.g.
+     *  print_r($mydb->filterTags('linux programming'));
+     *
+     * @param string $tags          list of tags separated by commas or blank spaces.
+     * @param bool   $casesensitive ignore case if false.
+     * @param string $visibility    Optional: return only all/private/public links.
+     *
+     * @return array filtered links.
+     */
+    public function filterTags($tags, $casesensitive = false, $visibility = 'all')
+    {
+        // get single tags (we may get passed an array, even though the docs say different)
+        $inputTags = $tags;
+        if (!is_array($tags)) {
+            // we got an input string, split tags
+            $inputTags = preg_split('/(?:\s+)|,/', $inputTags, -1, PREG_SPLIT_NO_EMPTY);
+        }
+
+        if (!count($inputTags)) {
+            // no input tags
+            return $this->noFilter($visibility);
+        }
+
+        // build regex from all tags
+        $re = '/^' . implode(array_map("self::tag2regex", $inputTags)) . '.*$/';
+        if (!$casesensitive) {
+            // make regex case insensitive
+            $re .= 'i';
+        }
+
+        // create resulting array
+        $filtered = array();
+
+        // iterate over each link
+        foreach ($this->links as $key => $link) {
+            // check level of visibility
+            // ignore non private links when 'privateonly' is on.
+            if ($visibility !== 'all') {
+                if (!$link['private'] && $visibility === 'private') {
+                    continue;
+                } elseif ($link['private'] && $visibility === 'public') {
+                    continue;
+                }
+            }
+            $search = $link['tags']; // build search string, start with tags of current link
+            if (strlen(trim($link['description'])) && strpos($link['description'], '#') !== false) {
+                // description given and at least one possible tag found
+                $descTags = array();
+                // find all tags in the form of #tag in the description
+                preg_match_all(
+                    '/(?<![' . self::$HASHTAG_CHARS . '])#([' . self::$HASHTAG_CHARS . ']+?)\b/sm',
+                    $link['description'],
+                    $descTags
+                );
+                if (count($descTags[1])) {
+                    // there were some tags in the description, add them to the search string
+                    $search .= ' ' . implode(' ', $descTags[1]);
+                }
+            };
+            // match regular expression with search string
+            if (!preg_match($re, $search)) {
+                // this entry does _not_ match our regex
+                continue;
+            }
+            $filtered[$key] = $link;
+        }
+        return $filtered;
+    }
+
+    /**
+     * Return only links without any tag.
+     *
+     * @param string $visibility return only all/private/public links.
+     *
+     * @return array filtered links.
+     */
+    public function filterUntagged($visibility)
+    {
+        $filtered = [];
+        foreach ($this->links as $key => $link) {
+            if ($visibility !== 'all') {
+                if (!$link['private'] && $visibility === 'private') {
+                    continue;
+                } elseif ($link['private'] && $visibility === 'public') {
+                    continue;
+                }
+            }
+
+            if (empty(trim($link['tags']))) {
+                $filtered[$key] = $link;
+            }
+        }
+
+        return $filtered;
+    }
+
+    /**
+     * Returns the list of articles for a given day, chronologically sorted
+     *
+     * Day must be in the form 'YYYYMMDD' (e.g. '20120125'), e.g.
+     *  print_r($mydb->filterDay('20120125'));
+     *
+     * @param string $day day to filter.
+     *
+     * @return array all link matching given day.
+     *
+     * @throws Exception if date format is invalid.
+     */
+    public function filterDay($day)
+    {
+        if (!checkDateFormat('Ymd', $day)) {
+            throw new Exception('Invalid date format');
+        }
+
+        $filtered = array();
+        foreach ($this->links as $key => $l) {
+            if ($l['created']->format('Ymd') == $day) {
+                $filtered[$key] = $l;
+            }
+        }
+
+        // sort by date ASC
+        return array_reverse($filtered, true);
+    }
+
+    /**
+     * Convert a list of tags (str) to an array. Also
+     * - handle case sensitivity.
+     * - accepts spaces commas as separator.
+     *
+     * @param string $tags          string containing a list of tags.
+     * @param bool   $casesensitive will convert everything to lowercase if false.
+     *
+     * @return array filtered tags string.
+     */
+    public static function tagsStrToArray($tags, $casesensitive)
+    {
+        // We use UTF-8 conversion to handle various graphemes (i.e. cyrillic, or greek)
+        $tagsOut = $casesensitive ? $tags : mb_convert_case($tags, MB_CASE_LOWER, 'UTF-8');
+        $tagsOut = str_replace(',', ' ', $tagsOut);
+
+        return preg_split('/\s+/', $tagsOut, -1, PREG_SPLIT_NO_EMPTY);
+    }
+}
diff --git a/application/legacy/LegacyUpdater.php b/application/legacy/LegacyUpdater.php
new file mode 100644
index 00000000..3a5de79f
--- /dev/null
+++ b/application/legacy/LegacyUpdater.php
@@ -0,0 +1,617 @@
+<?php
+
+namespace Shaarli\Legacy;
+
+use Exception;
+use RainTPL;
+use ReflectionClass;
+use ReflectionException;
+use ReflectionMethod;
+use Shaarli\ApplicationUtils;
+use Shaarli\Bookmark\Bookmark;
+use Shaarli\Bookmark\BookmarkArray;
+use Shaarli\Bookmark\LinkDB;
+use Shaarli\Bookmark\BookmarkFilter;
+use Shaarli\Bookmark\BookmarkIO;
+use Shaarli\Config\ConfigJson;
+use Shaarli\Config\ConfigManager;
+use Shaarli\Config\ConfigPhp;
+use Shaarli\Exceptions\IOException;
+use Shaarli\Thumbnailer;
+use Shaarli\Updater\Exception\UpdaterException;
+
+/**
+ * Class updater.
+ * Used to update stuff when a new Shaarli's version is reached.
+ * Update methods are ran only once, and the stored in a JSON file.
+ *
+ * @deprecated
+ */
+class LegacyUpdater
+{
+    /**
+     * @var array Updates which are already done.
+     */
+    protected $doneUpdates;
+
+    /**
+     * @var LegacyLinkDB instance.
+     */
+    protected $linkDB;
+
+    /**
+     * @var ConfigManager $conf Configuration Manager instance.
+     */
+    protected $conf;
+
+    /**
+     * @var bool True if the user is logged in, false otherwise.
+     */
+    protected $isLoggedIn;
+
+    /**
+     * @var array $_SESSION
+     */
+    protected $session;
+
+    /**
+     * @var ReflectionMethod[] List of current class methods.
+     */
+    protected $methods;
+
+    /**
+     * Object constructor.
+     *
+     * @param array         $doneUpdates Updates which are already done.
+     * @param LegacyLinkDB  $linkDB      LinkDB instance.
+     * @param ConfigManager $conf        Configuration Manager instance.
+     * @param boolean       $isLoggedIn  True if the user is logged in.
+     * @param array         $session     $_SESSION (by reference)
+     *
+     * @throws ReflectionException
+     */
+    public function __construct($doneUpdates, $linkDB, $conf, $isLoggedIn, &$session = [])
+    {
+        $this->doneUpdates = $doneUpdates;
+        $this->linkDB = $linkDB;
+        $this->conf = $conf;
+        $this->isLoggedIn = $isLoggedIn;
+        $this->session = &$session;
+
+        // Retrieve all update methods.
+        $class = new ReflectionClass($this);
+        $this->methods = $class->getMethods();
+    }
+
+    /**
+     * Run all new updates.
+     * Update methods have to start with 'updateMethod' and return true (on success).
+     *
+     * @return array An array containing ran updates.
+     *
+     * @throws UpdaterException If something went wrong.
+     */
+    public function update()
+    {
+        $updatesRan = array();
+
+        // If the user isn't logged in, exit without updating.
+        if ($this->isLoggedIn !== true) {
+            return $updatesRan;
+        }
+
+        if ($this->methods === null) {
+            throw new UpdaterException(t('Couldn\'t retrieve updater class methods.'));
+        }
+
+        foreach ($this->methods as $method) {
+            // Not an update method or already done, pass.
+            if (!startsWith($method->getName(), 'updateMethod')
+                || in_array($method->getName(), $this->doneUpdates)
+            ) {
+                continue;
+            }
+
+            try {
+                $method->setAccessible(true);
+                $res = $method->invoke($this);
+                // Update method must return true to be considered processed.
+                if ($res === true) {
+                    $updatesRan[] = $method->getName();
+                }
+            } catch (Exception $e) {
+                throw new UpdaterException($method, $e);
+            }
+        }
+
+        $this->doneUpdates = array_merge($this->doneUpdates, $updatesRan);
+
+        return $updatesRan;
+    }
+
+    /**
+     * @return array Updates methods already processed.
+     */
+    public function getDoneUpdates()
+    {
+        return $this->doneUpdates;
+    }
+
+    /**
+     * Move deprecated options.php to config.php.
+     *
+     * Milestone 0.9 (old versioning) - shaarli/Shaarli#41:
+     *    options.php is not supported anymore.
+     */
+    public function updateMethodMergeDeprecatedConfigFile()
+    {
+        if (is_file($this->conf->get('resource.data_dir') . '/options.php')) {
+            include $this->conf->get('resource.data_dir') . '/options.php';
+
+            // Load GLOBALS into config
+            $allowedKeys = array_merge(ConfigPhp::$ROOT_KEYS);
+            $allowedKeys[] = 'config';
+            foreach ($GLOBALS as $key => $value) {
+                if (in_array($key, $allowedKeys)) {
+                    $this->conf->set($key, $value);
+                }
+            }
+            $this->conf->write($this->isLoggedIn);
+            unlink($this->conf->get('resource.data_dir') . '/options.php');
+        }
+
+        return true;
+    }
+
+    /**
+     * Move old configuration in PHP to the new config system in JSON format.
+     *
+     * Will rename 'config.php' into 'config.save.php' and create 'config.json.php'.
+     * It will also convert legacy setting keys to the new ones.
+     */
+    public function updateMethodConfigToJson()
+    {
+        // JSON config already exists, nothing to do.
+        if ($this->conf->getConfigIO() instanceof ConfigJson) {
+            return true;
+        }
+
+        $configPhp = new ConfigPhp();
+        $configJson = new ConfigJson();
+        $oldConfig = $configPhp->read($this->conf->getConfigFile() . '.php');
+        rename($this->conf->getConfigFileExt(), $this->conf->getConfigFile() . '.save.php');
+        $this->conf->setConfigIO($configJson);
+        $this->conf->reload();
+
+        $legacyMap = array_flip(ConfigPhp::$LEGACY_KEYS_MAPPING);
+        foreach (ConfigPhp::$ROOT_KEYS as $key) {
+            $this->conf->set($legacyMap[$key], $oldConfig[$key]);
+        }
+
+        // Set sub config keys (config and plugins)
+        $subConfig = array('config', 'plugins');
+        foreach ($subConfig as $sub) {
+            foreach ($oldConfig[$sub] as $key => $value) {
+                if (isset($legacyMap[$sub . '.' . $key])) {
+                    $configKey = $legacyMap[$sub . '.' . $key];
+                } else {
+                    $configKey = $sub . '.' . $key;
+                }
+                $this->conf->set($configKey, $value);
+            }
+        }
+
+        try {
+            $this->conf->write($this->isLoggedIn);
+            return true;
+        } catch (IOException $e) {
+            error_log($e->getMessage());
+            return false;
+        }
+    }
+
+    /**
+     * Escape settings which have been manually escaped in every request in previous versions:
+     *   - general.title
+     *   - general.header_link
+     *   - redirector.url
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodEscapeUnescapedConfig()
+    {
+        try {
+            $this->conf->set('general.title', escape($this->conf->get('general.title')));
+            $this->conf->set('general.header_link', escape($this->conf->get('general.header_link')));
+            $this->conf->write($this->isLoggedIn);
+        } catch (Exception $e) {
+            error_log($e->getMessage());
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Update the database to use the new ID system, which replaces linkdate primary keys.
+     * Also, creation and update dates are now DateTime objects (done by LinkDB).
+     *
+     * Since this update is very sensitve (changing the whole database), the datastore will be
+     * automatically backed up into the file datastore.<datetime>.php.
+     *
+     * LinkDB also adds the field 'shorturl' with the precedent format (linkdate smallhash),
+     * which will be saved by this method.
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodDatastoreIds()
+    {
+        $first = 'update';
+        foreach ($this->linkDB as $key => $link) {
+            $first = $key;
+            break;
+        }
+
+        // up to date database
+        if (is_int($first)) {
+            return true;
+        }
+
+        $save = $this->conf->get('resource.data_dir') . '/datastore.' . date('YmdHis') . '.php';
+        copy($this->conf->get('resource.datastore'), $save);
+
+        $links = array();
+        foreach ($this->linkDB as $offset => $value) {
+            $links[] = $value;
+            unset($this->linkDB[$offset]);
+        }
+        $links = array_reverse($links);
+        $cpt = 0;
+        foreach ($links as $l) {
+            unset($l['linkdate']);
+            $l['id'] = $cpt;
+            $this->linkDB[$cpt++] = $l;
+        }
+
+        $this->linkDB->save($this->conf->get('resource.page_cache'));
+        $this->linkDB->reorder();
+
+        return true;
+    }
+
+    /**
+     * Rename tags starting with a '-' to work with tag exclusion search.
+     */
+    public function updateMethodRenameDashTags()
+    {
+        $linklist = $this->linkDB->filterSearch();
+        foreach ($linklist as $key => $link) {
+            $link['tags'] = preg_replace('/(^| )\-/', '$1', $link['tags']);
+            $link['tags'] = implode(' ', array_unique(BookmarkFilter::tagsStrToArray($link['tags'], true)));
+            $this->linkDB[$key] = $link;
+        }
+        $this->linkDB->save($this->conf->get('resource.page_cache'));
+        return true;
+    }
+
+    /**
+     * Initialize API settings:
+     *   - api.enabled: true
+     *   - api.secret: generated secret
+     */
+    public function updateMethodApiSettings()
+    {
+        if ($this->conf->exists('api.secret')) {
+            return true;
+        }
+
+        $this->conf->set('api.enabled', true);
+        $this->conf->set(
+            'api.secret',
+            generate_api_secret(
+                $this->conf->get('credentials.login'),
+                $this->conf->get('credentials.salt')
+            )
+        );
+        $this->conf->write($this->isLoggedIn);
+        return true;
+    }
+
+    /**
+     * New setting: theme name. If the default theme is used, nothing to do.
+     *
+     * If the user uses a custom theme, raintpl_tpl dir is updated to the parent directory,
+     * and the current theme is set as default in the theme setting.
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodDefaultTheme()
+    {
+        // raintpl_tpl isn't the root template directory anymore.
+        // We run the update only if this folder still contains the template files.
+        $tplDir = $this->conf->get('resource.raintpl_tpl');
+        $tplFile = $tplDir . '/linklist.html';
+        if (!file_exists($tplFile)) {
+            return true;
+        }
+
+        $parent = dirname($tplDir);
+        $this->conf->set('resource.raintpl_tpl', $parent);
+        $this->conf->set('resource.theme', trim(str_replace($parent, '', $tplDir), '/'));
+        $this->conf->write($this->isLoggedIn);
+
+        // Dependency injection gore
+        RainTPL::$tpl_dir = $tplDir;
+
+        return true;
+    }
+
+    /**
+     * Move the file to inc/user.css to data/user.css.
+     *
+     * Note: Due to hardcoded paths, it's not unit testable. But one line of code should be fine.
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodMoveUserCss()
+    {
+        if (!is_file('inc/user.css')) {
+            return true;
+        }
+
+        return rename('inc/user.css', 'data/user.css');
+    }
+
+    /**
+     * * `markdown_escape` is a new setting, set to true as default.
+     *
+     * If the markdown plugin was already enabled, escaping is disabled to avoid
+     * breaking existing entries.
+     */
+    public function updateMethodEscapeMarkdown()
+    {
+        if ($this->conf->exists('security.markdown_escape')) {
+            return true;
+        }
+
+        if (in_array('markdown', $this->conf->get('general.enabled_plugins'))) {
+            $this->conf->set('security.markdown_escape', false);
+        } else {
+            $this->conf->set('security.markdown_escape', true);
+        }
+        $this->conf->write($this->isLoggedIn);
+
+        return true;
+    }
+
+    /**
+     * Add 'http://' to Piwik URL the setting is set.
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodPiwikUrl()
+    {
+        if (!$this->conf->exists('plugins.PIWIK_URL') || startsWith($this->conf->get('plugins.PIWIK_URL'), 'http')) {
+            return true;
+        }
+
+        $this->conf->set('plugins.PIWIK_URL', 'http://' . $this->conf->get('plugins.PIWIK_URL'));
+        $this->conf->write($this->isLoggedIn);
+
+        return true;
+    }
+
+    /**
+     * Use ATOM feed as default.
+     */
+    public function updateMethodAtomDefault()
+    {
+        if (!$this->conf->exists('feed.show_atom') || $this->conf->get('feed.show_atom') === true) {
+            return true;
+        }
+
+        $this->conf->set('feed.show_atom', true);
+        $this->conf->write($this->isLoggedIn);
+
+        return true;
+    }
+
+    /**
+     * Update updates.check_updates_branch setting.
+     *
+     * If the current major version digit matches the latest branch
+     * major version digit, we set the branch to `latest`,
+     * otherwise we'll check updates on the `stable` branch.
+     *
+     * No update required for the dev version.
+     *
+     * Note: due to hardcoded URL and lack of dependency injection, this is not unit testable.
+     *
+     * FIXME! This needs to be removed when we switch to first digit major version
+     *        instead of the second one since the versionning process will change.
+     */
+    public function updateMethodCheckUpdateRemoteBranch()
+    {
+        if (SHAARLI_VERSION === 'dev' || $this->conf->get('updates.check_updates_branch') === 'latest') {
+            return true;
+        }
+
+        // Get latest branch major version digit
+        $latestVersion = ApplicationUtils::getLatestGitVersionCode(
+            'https://raw.githubusercontent.com/shaarli/Shaarli/latest/shaarli_version.php',
+            5
+        );
+        if (preg_match('/(\d+)\.\d+$/', $latestVersion, $matches) === false) {
+            return false;
+        }
+        $latestMajor = $matches[1];
+
+        // Get current major version digit
+        preg_match('/(\d+)\.\d+$/', SHAARLI_VERSION, $matches);
+        $currentMajor = $matches[1];
+
+        if ($currentMajor === $latestMajor) {
+            $branch = 'latest';
+        } else {
+            $branch = 'stable';
+        }
+        $this->conf->set('updates.check_updates_branch', $branch);
+        $this->conf->write($this->isLoggedIn);
+        return true;
+    }
+
+    /**
+     * Reset history store file due to date format change.
+     */
+    public function updateMethodResetHistoryFile()
+    {
+        if (is_file($this->conf->get('resource.history'))) {
+            unlink($this->conf->get('resource.history'));
+        }
+        return true;
+    }
+
+    /**
+     * Save the datastore -> the link order is now applied when bookmarks are saved.
+     */
+    public function updateMethodReorderDatastore()
+    {
+        $this->linkDB->save($this->conf->get('resource.page_cache'));
+        return true;
+    }
+
+    /**
+     * Change privateonly session key to visibility.
+     */
+    public function updateMethodVisibilitySession()
+    {
+        if (isset($_SESSION['privateonly'])) {
+            unset($_SESSION['privateonly']);
+            $_SESSION['visibility'] = 'private';
+        }
+        return true;
+    }
+
+    /**
+     * Add download size and timeout to the configuration file
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodDownloadSizeAndTimeoutConf()
+    {
+        if ($this->conf->exists('general.download_max_size')
+            && $this->conf->exists('general.download_timeout')
+        ) {
+            return true;
+        }
+
+        if (!$this->conf->exists('general.download_max_size')) {
+            $this->conf->set('general.download_max_size', 1024 * 1024 * 4);
+        }
+
+        if (!$this->conf->exists('general.download_timeout')) {
+            $this->conf->set('general.download_timeout', 30);
+        }
+
+        $this->conf->write($this->isLoggedIn);
+        return true;
+    }
+
+    /**
+     * * Move thumbnails management to WebThumbnailer, coming with new settings.
+     */
+    public function updateMethodWebThumbnailer()
+    {
+        if ($this->conf->exists('thumbnails.mode')) {
+            return true;
+        }
+
+        $thumbnailsEnabled = extension_loaded('gd') && $this->conf->get('thumbnail.enable_thumbnails', true);
+        $this->conf->set('thumbnails.mode', $thumbnailsEnabled ? Thumbnailer::MODE_ALL : Thumbnailer::MODE_NONE);
+        $this->conf->set('thumbnails.width', 125);
+        $this->conf->set('thumbnails.height', 90);
+        $this->conf->remove('thumbnail');
+        $this->conf->write(true);
+
+        if ($thumbnailsEnabled) {
+            $this->session['warnings'][] = t(
+                'You have enabled or changed thumbnails mode. <a href="?do=thumbs_update">Please synchronize them</a>.'
+            );
+        }
+
+        return true;
+    }
+
+    /**
+     * Set sticky = false on all bookmarks
+     *
+     * @return bool true if the update is successful, false otherwise.
+     */
+    public function updateMethodSetSticky()
+    {
+        foreach ($this->linkDB as $key => $link) {
+            if (isset($link['sticky'])) {
+                return true;
+            }
+            $link['sticky'] = false;
+            $this->linkDB[$key] = $link;
+        }
+
+        $this->linkDB->save($this->conf->get('resource.page_cache'));
+
+        return true;
+    }
+
+    /**
+     * Remove redirector settings.
+     */
+    public function updateMethodRemoveRedirector()
+    {
+        $this->conf->remove('redirector');
+        $this->conf->write(true);
+        return true;
+    }
+
+    /**
+     * Migrate the legacy arrays to Bookmark objects.
+     * Also make a backup of the datastore.
+     */
+    public function updateMethodMigrateDatabase()
+    {
+        $save = $this->conf->get('resource.data_dir') . '/datastore.' . date('YmdHis') . '_1.php';
+        if (! copy($this->conf->get('resource.datastore'), $save)) {
+            die('Could not backup the datastore.');
+        }
+
+        $linksArray = new BookmarkArray();
+        foreach ($this->linkDB as $key => $link) {
+            $linksArray[$key] = (new Bookmark())->fromArray($link);
+        }
+        $linksIo = new BookmarkIO($this->conf);
+        $linksIo->write($linksArray);
+
+        return true;
+    }
+
+    /**
+     * Write the `formatter` setting in config file.
+     * Use markdown if the markdown plugin is enabled, the default one otherwise.
+     * Also remove markdown plugin setting as it is now integrated to the core.
+     */
+    public function updateMethodFormatterSetting()
+    {
+        if (!$this->conf->exists('formatter') || $this->conf->get('formatter') === 'default') {
+            $enabledPlugins = $this->conf->get('general.enabled_plugins');
+            if (($pos = array_search('markdown', $enabledPlugins)) !== false) {
+                $formatter = 'markdown';
+                unset($enabledPlugins[$pos]);
+                $this->conf->set('general.enabled_plugins', array_values($enabledPlugins));
+            } else {
+                $formatter = 'default';
+            }
+            $this->conf->set('formatter', $formatter);
+            $this->conf->write(true);
+        }
+
+        return true;
+    }
+}