7 files changed, 349 insertions, 35 deletions

diff --git a/application/bookmark/Bookmark.php b/application/bookmark/Bookmark.php
index fa45d2fc..ea565d1f 100644
--- a/application/bookmark/Bookmark.php
+++ b/application/bookmark/Bookmark.php
@@ -54,6 +54,9 @@ class Bookmark
     /** @var bool True if the bookmark can only be seen while logged in */
     protected $private;
 
+    /** @var mixed[] Available to store any additional content for a bookmark. Currently used for search highlight. */
+    protected $additionalContent = [];
+
     /**
      * Initialize a link from array data. Especially useful to create a Bookmark from former link storage format.
      *
@@ -95,6 +98,8 @@ class Bookmark
      *   - the URL with the permalink
      *   - the title with the URL
      *
+     * Also make sure that we do not save search highlights in the datastore.
+     *
      * @throws InvalidBookmarkException
      */
     public function validate(): void
@@ -112,6 +117,9 @@ class Bookmark
         if (empty($this->title)) {
             $this->title = $this->url;
         }
+        if (array_key_exists('search_highlight', $this->additionalContent)) {
+            unset($this->additionalContent['search_highlight']);
+        }
     }
 
     /**
@@ -436,6 +444,44 @@ class Bookmark
     }
 
     /**
+     * Get entire additionalContent array.
+     *
+     * @return mixed[]
+     */
+    public function getAdditionalContent(): array
+    {
+        return $this->additionalContent;
+    }
+
+    /**
+     * Set a single entry in additionalContent, by key.
+     *
+     * @param string     $key
+     * @param mixed|null $value Any type of value can be set.
+     *
+     * @return $this
+     */
+    public function addAdditionalContentEntry(string $key, $value): self
+    {
+        $this->additionalContent[$key] = $value;
+
+        return $this;
+    }
+
+    /**
+     * Get a single entry in additionalContent, by key.
+     *
+     * @param string $key
+     * @param mixed|null $default
+     *
+     * @return mixed|null can be any type or even null.
+     */
+    public function getAdditionalContentEntry(string $key, $default = null)
+    {
+        return array_key_exists($key, $this->additionalContent) ? $this->additionalContent[$key] : $default;
+    }
+
+    /**
      * Rename a tag in tags list.
      *
      * @param string $fromTag
diff --git a/application/bookmark/BookmarkFilter.php b/application/bookmark/BookmarkFilter.php
index 4232f114..c79386ea 100644
--- a/application/bookmark/BookmarkFilter.php
+++ b/application/bookmark/BookmarkFilter.php
@@ -201,7 +201,7 @@ class BookmarkFilter
             return $this->noFilter($visibility);
         }
 
-        $filtered = array();
+        $filtered = [];
         $search = mb_convert_case(html_entity_decode($searchterms), MB_CASE_LOWER, 'UTF-8');
         $exactRegex = '/"([^"]+)"/';
         // Retrieve exact search terms.
@@ -213,8 +213,8 @@ class BookmarkFilter
         $explodedSearchAnd = array_values(array_filter($explodedSearchAnd));
 
         // Filter excluding terms and update andSearch.
-        $excludeSearch = array();
-        $andSearch = array();
+        $excludeSearch = [];
+        $andSearch = [];
         foreach ($explodedSearchAnd as $needle) {
             if ($needle[0] == '-' && strlen($needle) > 1) {
                 $excludeSearch[] = substr($needle, 1);
@@ -234,33 +234,38 @@ class BookmarkFilter
                 }
             }
 
-            // Concatenate link fields to search across fields.
-            // Adds a '\' separator for exact search terms.
-            $content  = mb_convert_case($link->getTitle(), MB_CASE_LOWER, 'UTF-8') .'\\';
-            $content .= mb_convert_case($link->getDescription(), MB_CASE_LOWER, 'UTF-8') .'\\';
-            $content .= mb_convert_case($link->getUrl(), MB_CASE_LOWER, 'UTF-8') .'\\';
-            $content .= mb_convert_case($link->getTagsString(), MB_CASE_LOWER, 'UTF-8') .'\\';
+            $lengths = [];
+            $content = $this->buildFullTextSearchableLink($link, $lengths);
 
             // Be optimistic
             $found = true;
+            $foundPositions = [];
 
             // 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,
+            // Then 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;
+            foreach ([$exactSearch, $andSearch] as $search) {
+                for ($i = 0; $i < count($search) && $found !== false; $i++) {
+                    $found = mb_strpos($content, $search[$i]);
+                    if ($found === false) {
+                        break;
+                    }
+
+                    $foundPositions[] = ['start' => $found, 'end' => $found + mb_strlen($search[$i])];
+                }
             }
 
             // Exclude terms.
-            for ($i = 0; $i < count($excludeSearch) && $found; $i++) {
+            for ($i = 0; $i < count($excludeSearch) && $found !== false; $i++) {
                 $found = strpos($content, $excludeSearch[$i]) === false;
             }
 
-            if ($found) {
+            if ($found !== false) {
+                $link->addAdditionalContentEntry(
+                    'search_highlight',
+                    $this->postProcessFoundPositions($lengths, $foundPositions)
+                );
+
                 $filtered[$id] = $link;
             }
         }
@@ -477,4 +482,74 @@ class BookmarkFilter
 
         return preg_split('/\s+/', $tagsOut, -1, PREG_SPLIT_NO_EMPTY);
     }
+
+    /**
+     * This method finalize the content of the foundPositions array,
+     * by associated all search results to their associated bookmark field,
+     * making sure that there is no overlapping results, etc.
+     *
+     * @param array $fieldLengths   Start and end positions of every bookmark fields in the aggregated bookmark content.
+     * @param array $foundPositions Positions where the search results were found in the aggregated content.
+     *
+     * @return array Updated $foundPositions, by bookmark field.
+     */
+    protected function postProcessFoundPositions(array $fieldLengths, array $foundPositions): array
+    {
+        // Sort results by starting position ASC.
+        usort($foundPositions, function (array $entryA, array $entryB): int {
+            return $entryA['start'] > $entryB['start'] ? 1 : -1;
+        });
+
+        $out = [];
+        $currentMax = -1;
+        foreach ($foundPositions as $foundPosition) {
+            // we do not allow overlapping highlights
+            if ($foundPosition['start'] < $currentMax) {
+                continue;
+            }
+
+            $currentMax = $foundPosition['end'];
+            foreach ($fieldLengths as $part => $length) {
+                if ($foundPosition['start'] < $length['start'] || $foundPosition['start'] > $length['end']) {
+                    continue;
+                }
+
+                $out[$part][] = [
+                    'start' => $foundPosition['start'] - $length['start'],
+                    'end' => $foundPosition['end'] - $length['start'],
+                ];
+                break;
+            }
+        }
+
+        return $out;
+    }
+
+    /**
+     * Concatenate link fields to search across fields. Adds a '\' separator for exact search terms.
+     * Also populate $length array with starting and ending positions of every bookmark field
+     * inside concatenated content.
+     *
+     * @param Bookmark $link
+     * @param array    $lengths (by reference)
+     *
+     * @return string Lowercase concatenated fields content.
+     */
+    protected function buildFullTextSearchableLink(Bookmark $link, array &$lengths): string
+    {
+        $content  = mb_convert_case($link->getTitle(), MB_CASE_LOWER, 'UTF-8') .'\\';
+        $content .= mb_convert_case($link->getDescription(), MB_CASE_LOWER, 'UTF-8') .'\\';
+        $content .= mb_convert_case($link->getUrl(), MB_CASE_LOWER, 'UTF-8') .'\\';
+        $content .= mb_convert_case($link->getTagsString(), MB_CASE_LOWER, 'UTF-8') .'\\';
+
+        $lengths['title'] = ['start' => 0, 'end' => mb_strlen($link->getTitle())];
+        $nextField = $lengths['title']['end'] + 1;
+        $lengths['description'] = ['start' => $nextField, 'end' => $nextField + mb_strlen($link->getDescription())];
+        $nextField = $lengths['description']['end'] + 1;
+        $lengths['url'] = ['start' => $nextField, 'end' => $nextField + mb_strlen($link->getUrl())];
+        $nextField = $lengths['url']['end'] + 1;
+        $lengths['tags'] = ['start' => $nextField, 'end' => $nextField + mb_strlen($link->getTagsString())];
+
+        return $content;
+    }
 }
diff --git a/application/formatter/BookmarkDefaultFormatter.php b/application/formatter/BookmarkDefaultFormatter.php
index 9d4a0fa0..d58a5e39 100644
--- a/application/formatter/BookmarkDefaultFormatter.php
+++ b/application/formatter/BookmarkDefaultFormatter.php
@@ -12,10 +12,13 @@ namespace Shaarli\Formatter;
  */
 class BookmarkDefaultFormatter extends BookmarkFormatter
 {
+    const SEARCH_HIGHLIGHT_OPEN = '|@@HIGHLIGHT';
+    const SEARCH_HIGHLIGHT_CLOSE = 'HIGHLIGHT@@|';
+
     /**
      * @inheritdoc
      */
-    public function formatTitle($bookmark)
+    protected function formatTitle($bookmark)
     {
         return escape($bookmark->getTitle());
     }
@@ -23,10 +26,28 @@ class BookmarkDefaultFormatter extends BookmarkFormatter
     /**
      * @inheritdoc
      */
-    public function formatDescription($bookmark)
+    protected function formatTitleHtml($bookmark)
+    {
+        $title = $this->tokenizeSearchHighlightField(
+            $bookmark->getTitle() ?? '',
+            $bookmark->getAdditionalContentEntry('search_highlight')['title'] ?? []
+        );
+
+        return $this->replaceTokens(escape($title));
+    }
+
+    /**
+     * @inheritdoc
+     */
+    protected function formatDescription($bookmark)
     {
         $indexUrl = ! empty($this->contextData['index_url']) ? $this->contextData['index_url'] : '';
-        return format_description(escape($bookmark->getDescription()), $indexUrl);
+        $description = $this->tokenizeSearchHighlightField(
+            $bookmark->getDescription() ?? '',
+            $bookmark->getAdditionalContentEntry('search_highlight')['description'] ?? []
+        );
+
+        return $this->replaceTokens(format_description(escape($description), $indexUrl));
     }
 
     /**
@@ -40,7 +61,27 @@ class BookmarkDefaultFormatter extends BookmarkFormatter
     /**
      * @inheritdoc
      */
-    public function formatTagString($bookmark)
+    protected function formatTagListHtml($bookmark)
+    {
+        if (empty($bookmark->getAdditionalContentEntry('search_highlight')['tags'])) {
+            return $this->formatTagList($bookmark);
+        }
+
+        $tags = $this->tokenizeSearchHighlightField(
+            $bookmark->getTagsString(),
+            $bookmark->getAdditionalContentEntry('search_highlight')['tags']
+        );
+        $tags = $this->filterTagList(explode(' ', $tags));
+        $tags = escape($tags);
+        $tags = $this->replaceTokensArray($tags);
+
+        return $tags;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    protected function formatTagString($bookmark)
     {
         return implode(' ', $this->formatTagList($bookmark));
     }
@@ -48,7 +89,7 @@ class BookmarkDefaultFormatter extends BookmarkFormatter
     /**
      * @inheritdoc
      */
-    public function formatUrl($bookmark)
+    protected function formatUrl($bookmark)
     {
         if ($bookmark->isNote() && isset($this->contextData['index_url'])) {
             return rtrim($this->contextData['index_url'], '/') . '/' . escape(ltrim($bookmark->getUrl(), '/'));
@@ -80,8 +121,89 @@ class BookmarkDefaultFormatter extends BookmarkFormatter
     /**
      * @inheritdoc
      */
+    protected function formatUrlHtml($bookmark)
+    {
+        $url = $this->tokenizeSearchHighlightField(
+            $bookmark->getUrl() ?? '',
+            $bookmark->getAdditionalContentEntry('search_highlight')['url'] ?? []
+        );
+
+        return $this->replaceTokens(escape($url));
+    }
+
+    /**
+     * @inheritdoc
+     */
     protected function formatThumbnail($bookmark)
     {
         return escape($bookmark->getThumbnail());
     }
+
+    /**
+     * Insert search highlight token in provided field content based on a list of search result positions
+     *
+     * @param string     $fieldContent
+     * @param array|null $positions    List of of search results with 'start' and 'end' positions.
+     *
+     * @return string Updated $fieldContent.
+     */
+    protected function tokenizeSearchHighlightField(string $fieldContent, ?array $positions): string
+    {
+        if (empty($positions)) {
+            return $fieldContent;
+        }
+
+        $insertedTokens = 0;
+        $tokenLength = strlen(static::SEARCH_HIGHLIGHT_OPEN);
+        foreach ($positions as $position) {
+            $position = [
+                'start' => $position['start'] + ($insertedTokens * $tokenLength),
+                'end' => $position['end'] + ($insertedTokens * $tokenLength),
+            ];
+
+            $content = mb_substr($fieldContent, 0, $position['start']);
+            $content .= static::SEARCH_HIGHLIGHT_OPEN;
+            $content .= mb_substr($fieldContent, $position['start'], $position['end'] - $position['start']);
+            $content .= static::SEARCH_HIGHLIGHT_CLOSE;
+            $content .= mb_substr($fieldContent, $position['end']);
+
+            $fieldContent = $content;
+
+            $insertedTokens += 2;
+        }
+
+        return $fieldContent;
+    }
+
+    /**
+     * Replace search highlight tokens with HTML highlighted span.
+     *
+     * @param string $fieldContent
+     *
+     * @return string updated content.
+     */
+    protected function replaceTokens(string $fieldContent): string
+    {
+        return str_replace(
+            [static::SEARCH_HIGHLIGHT_OPEN, static::SEARCH_HIGHLIGHT_CLOSE],
+            ['<span class="search-highlight">', '</span>'],
+            $fieldContent
+        );
+    }
+
+    /**
+     * Apply replaceTokens to an array of content strings.
+     *
+     * @param string[] $fieldContents
+     *
+     * @return array
+     */
+    protected function replaceTokensArray(array $fieldContents): array
+    {
+        foreach ($fieldContents as &$entry) {
+            $entry = $this->replaceTokens($entry);
+        }
+
+        return $fieldContents;
+    }
 }
diff --git a/application/formatter/BookmarkFormatter.php b/application/formatter/BookmarkFormatter.php
index 0042dafe..e1b7f705 100644
--- a/application/formatter/BookmarkFormatter.php
+++ b/application/formatter/BookmarkFormatter.php
@@ -2,7 +2,7 @@
 
 namespace Shaarli\Formatter;
 
-use DateTime;
+use DateTimeInterface;
 use Shaarli\Bookmark\Bookmark;
 use Shaarli\Config\ConfigManager;
 
@@ -11,6 +11,29 @@ use Shaarli\Config\ConfigManager;
  *
  * Abstract class processing all bookmark attributes through methods designed to be overridden.
  *
+ * List of available formatted fields:
+ *   - id                 ID
+ *   - shorturl           Unique identifier, used in permalinks
+ *   - url                URL, can be altered in some way, e.g. passing through an HTTP reverse proxy
+ *   - real_url           (legacy) same as `url`
+ *   - url_html           URL to be displayed in HTML content (it can contain HTML tags)
+ *   - title              Title
+ *   - title_html         Title to be displayed in HTML content (it can contain HTML tags)
+ *   - description        Description content. It most likely contains HTML tags
+ *   - thumbnail          Thumbnail: path to local cache file, false if there is none, null if hasn't been retrieved
+ *   - taglist            List of tags (array)
+ *   - taglist_urlencoded List of tags (array) URL encoded: it must be used to create a link to a URL containing a tag
+ *   - taglist_html       List of tags (array) to be displayed in HTML content (it can contain HTML tags)
+ *   - tags               Tags separated by a single whitespace
+ *   - tags_urlencoded    Tags separated by a single whitespace, URL encoded: must be used to create a link
+ *   - sticky             Is sticky (bool)
+ *   - private            Is private (bool)
+ *   - class              Additional CSS class
+ *   - created            Creation DateTime
+ *   - updated            Last edit DateTime
+ *   - timestamp          Creation timestamp
+ *   - updated_timestamp  Last edit timestamp
+ *
  * @package Shaarli\Formatter
  */
 abstract class BookmarkFormatter
@@ -55,13 +78,16 @@ abstract class BookmarkFormatter
         $out['shorturl'] = $this->formatShortUrl($bookmark);
         $out['url'] = $this->formatUrl($bookmark);
         $out['real_url'] = $this->formatRealUrl($bookmark);
+        $out['url_html'] = $this->formatUrlHtml($bookmark);
         $out['title'] = $this->formatTitle($bookmark);
+        $out['title_html'] = $this->formatTitleHtml($bookmark);
         $out['description'] = $this->formatDescription($bookmark);
         $out['thumbnail'] = $this->formatThumbnail($bookmark);
-        $out['urlencoded_taglist'] = $this->formatUrlEncodedTagList($bookmark);
         $out['taglist'] = $this->formatTagList($bookmark);
-        $out['urlencoded_tags'] = $this->formatUrlEncodedTagString($bookmark);
+        $out['taglist_urlencoded'] = $this->formatTagListUrlEncoded($bookmark);
+        $out['taglist_html'] = $this->formatTagListHtml($bookmark);
         $out['tags'] = $this->formatTagString($bookmark);
+        $out['tags_urlencoded'] = $this->formatTagStringUrlEncoded($bookmark);
         $out['sticky'] = $bookmark->isSticky();
         $out['private'] = $bookmark->isPrivate();
         $out['class'] = $this->formatClass($bookmark);
@@ -69,6 +95,7 @@ abstract class BookmarkFormatter
         $out['updated'] = $this->formatUpdated($bookmark);
         $out['timestamp'] = $this->formatCreatedTimestamp($bookmark);
         $out['updated_timestamp'] = $this->formatUpdatedTimestamp($bookmark);
+
         return $out;
     }
 
@@ -136,6 +163,18 @@ abstract class BookmarkFormatter
     }
 
     /**
+     * Format Url Html: to be displayed in HTML content, it can contains HTML tags.
+     *
+     * @param Bookmark $bookmark instance
+     *
+     * @return string formatted Url HTML
+     */
+    protected function formatUrlHtml($bookmark)
+    {
+        return $this->formatUrl($bookmark);
+    }
+
+    /**
      * Format Title
      *
      * @param Bookmark $bookmark instance
@@ -148,6 +187,18 @@ abstract class BookmarkFormatter
     }
 
     /**
+     * Format Title HTML: to be displayed in HTML content, it can contains HTML tags.
+     *
+     * @param Bookmark $bookmark instance
+     *
+     * @return string formatted Title
+     */
+    protected function formatTitleHtml($bookmark)
+    {
+        return $bookmark->getTitle();
+    }
+
+    /**
      * Format Description
      *
      * @param Bookmark $bookmark instance
@@ -190,12 +241,24 @@ abstract class BookmarkFormatter
      *
      * @return array formatted Tags
      */
-    protected function formatUrlEncodedTagList($bookmark)
+    protected function formatTagListUrlEncoded($bookmark)
     {
         return array_map('urlencode', $this->filterTagList($bookmark->getTags()));
     }
 
     /**
+     * Format Tags HTML: to be displayed in HTML content, it can contains HTML tags.
+     *
+     * @param Bookmark $bookmark instance
+     *
+     * @return array formatted Tags
+     */
+    protected function formatTagListHtml($bookmark)
+    {
+        return $this->formatTagList($bookmark);
+    }
+
+    /**
      * Format TagString
      *
      * @param Bookmark $bookmark instance
@@ -214,9 +277,9 @@ abstract class BookmarkFormatter
      *
      * @return string formatted TagString
      */
-    protected function formatUrlEncodedTagString($bookmark)
+    protected function formatTagStringUrlEncoded($bookmark)
     {
-        return implode(' ', $this->formatUrlEncodedTagList($bookmark));
+        return implode(' ', $this->formatTagListUrlEncoded($bookmark));
     }
 
     /**
@@ -237,7 +300,7 @@ abstract class BookmarkFormatter
      *
      * @param Bookmark $bookmark instance
      *
-     * @return DateTime instance
+     * @return DateTimeInterface instance
      */
     protected function formatCreated(Bookmark $bookmark)
     {
@@ -249,7 +312,7 @@ abstract class BookmarkFormatter
      *
      * @param Bookmark $bookmark instance
      *
-     * @return DateTime instance
+     * @return DateTimeInterface instance
      */
     protected function formatUpdated(Bookmark $bookmark)
     {
diff --git a/application/formatter/BookmarkMarkdownFormatter.php b/application/formatter/BookmarkMarkdownFormatter.php
index 5d244d4c..f7714be9 100644
--- a/application/formatter/BookmarkMarkdownFormatter.php
+++ b/application/formatter/BookmarkMarkdownFormatter.php
@@ -56,7 +56,10 @@ class BookmarkMarkdownFormatter extends BookmarkDefaultFormatter
             return parent::formatDescription($bookmark);
         }
 
-        $processedDescription = $bookmark->getDescription();
+        $processedDescription = $this->tokenizeSearchHighlightField(
+            $bookmark->getDescription() ?? '',
+            $bookmark->getAdditionalContentEntry('search_highlight')['description'] ?? []
+        );
         $processedDescription = $this->filterProtocols($processedDescription);
         $processedDescription = $this->formatHashTags($processedDescription);
         $processedDescription = $this->reverseEscapedHtml($processedDescription);
@@ -65,6 +68,7 @@ class BookmarkMarkdownFormatter extends BookmarkDefaultFormatter
             ->setBreaksEnabled(true)
             ->text($processedDescription);
         $processedDescription = $this->sanitizeHtml($processedDescription);
+        $processedDescription = $this->replaceTokens($processedDescription);
 
         if (!empty($processedDescription)) {
             $processedDescription = '<div class="markdown">'. $processedDescription . '</div>';
diff --git a/assets/default/scss/shaarli.scss b/assets/default/scss/shaarli.scss
index a528adb0..2f49bbd2 100644
--- a/assets/default/scss/shaarli.scss
+++ b/assets/default/scss/shaarli.scss
@@ -671,6 +671,10 @@ body,
       content: '';
     }
   }
+
+  .search-highlight {
+    background-color: yellow;
+  }
 }
 
 .linklist-item-buttons {
diff --git a/tpl/default/linklist.html b/tpl/default/linklist.html
index e1fb54dd..beab0eac 100644
--- a/tpl/default/linklist.html
+++ b/tpl/default/linklist.html
@@ -165,7 +165,7 @@
                   <i class="fa fa-sticky-note" aria-hidden="true"></i>
                 {/if}
 
-                <span class="linklist-link">{$value.title}</span>
+                <span class="linklist-link">{$value.title_html}</span>
               </a>
             </h2>
           </div>
@@ -183,7 +183,7 @@
                 {$tag_counter=count($value.taglist)}
                 {loop="value.taglist"}
                   <span class="label label-tag" title="{$strAddTag}">
-                    <a href="{$base_path}/add-tag/{$value1.urlencoded_taglist.$key2}">{$value}</a>
+                    <a href="{$base_path}/add-tag/{$value1.taglist_urlencoded.$key2}">{$value1.taglist_html.$key2}</a>
                   </span>
                   {if="$tag_counter - 1 != $counter"}&middot;{/if}
                 {/loop}
@@ -251,7 +251,7 @@
                 {ignore}do not add space or line break between these div - Firefox issue{/ignore}
                 class="linklist-item-infos-url pure-u-lg-5-12 pure-u-1">
                 <a href="{$value.real_url}" aria-label="{$value.title}" title="{$value.title}">
-                  <i class="fa fa-link" aria-hidden="true"></i> {$value.url}
+                  <i class="fa fa-link" aria-hidden="true"></i> {$value.url_html}
                 </a>
                 <div class="linklist-item-buttons pure-u-0 pure-u-lg-visible">
                   <a href="#" aria-label="{$strFold}" title="{$strFold}" class="fold-button"><i class="fa fa-chevron-up" aria-hidden="true"></i></a>