MDL-55459 assignfeedback_editpdf: Add linked comments and markers to PDF

mod/assign/feedback/editpdf/classes/document_services.php

@@ -634,17 +634,15 @@ EOD;
         $grade = $assignment->get_user_grade($userid, true, $attemptnumber);
         page_editor::release_drafts($grade->id);
 
+        $allcomments = array();
+
         for ($i = 0; $i < $pagecount; $i++) {
             $pdf->copy_page();
             $comments = page_editor::get_comments($grade->id, $i, false);
             $annotations = page_editor::get_annotations($grade->id, $i, false);
 
-            foreach ($comments as $comment) {
-                $pdf->add_comment($comment->rawtext,
-                                  $comment->x,
-                                  $comment->y,
-                                  $comment->width,
-                                  $comment->colour);
+            if (!empty($comments)) {
+                $allcomments[$i] = $comments;
             }
 
             foreach ($annotations as $annotation) {
@@ -659,6 +657,18 @@ EOD;
             }
         }
 
+        if (!empty($allcomments)) {
+            // Append all comments to the end of the document.
+            $links = $pdf->append_comments($allcomments);
+            // Add the comment markers with links.
+            foreach ($allcomments as $pageno => $comments) {
+                foreach ($comments as $index => $comment) {
+                    $pdf->add_comment_marker($comment->pageno, $index, $comment->x, $comment->y, $links[$pageno][$index],
+                            $comment->colour);
+                }
+            }
+        }
+
         fulldelete($stamptmpdir);
 
         $filename = self::get_downloadable_feedback_filename($assignment, $userid, $attemptnumber);

mod/assign/feedback/editpdf/classes/page_editor.php

@@ -50,7 +50,8 @@ class page_editor {
         if (!$draft) {
             $params['draft'] = 0;
         }
-        $records = $DB->get_records('assignfeedback_editpdf_cmnt', $params);
+        // Fetch comments ordered by position on the page.
+        $records = $DB->get_records('assignfeedback_editpdf_cmnt', $params, 'y, x');
         foreach ($records as $record) {
             array_push($comments, new comment($record));
         }

mod/assign/feedback/editpdf/classes/pdf.php

@@ -212,6 +212,109 @@ class pdf extends \FPDI {
         }
     }
 
+    /**
+     * Append all comments to the end of the document.
+     *
+     * @param array $allcomments All comments, indexed by page number (starting at 0).
+     * @return array|bool An array of links to comments, or false.
+     */
+    public function append_comments($allcomments) {
+        if (!$this->filename) {
+            return false;
+        }
+
+        $this->SetFontSize(12 * $this->scale);
+        $this->SetMargins(100 * $this->scale, 120 * $this->scale, -1, true);
+        $this->SetAutoPageBreak(true, 100 * $this->scale);
+        $this->setHeaderFont(array('helvetica', '', 24 * $this->scale));
+        $this->setHeaderMargin(24 * $this->scale);
+        $this->setHeaderData('', 0, '', get_string('commentindex', 'assignfeedback_editpdf'));
+
+        // Add a new page to the document with an appropriate header.
+        $this->setPrintHeader(true);
+        $this->AddPage();
+
+        // Add the comments.
+        $commentlinks = array();
+        foreach ($allcomments as $pageno => $comments) {
+            foreach ($comments as $index => $comment) {
+                // Create a link to the current location, which will be added to the marker.
+                $commentlink = $this->AddLink();
+                $this->SetLink($commentlink, -1);
+                $commentlinks[$pageno][$index] = $commentlink;
+                // Also create a link back to the marker, which will be added here.
+                $markerlink = $this->AddLink();
+                $this->SetLink($markerlink, $comment->y * $this->scale, $pageno + 1);
+                $label = get_string('commentlabel', 'assignfeedback_editpdf', array('pnum' => $pageno + 1, 'cnum' => $index + 1));
+                $this->Cell(50 * $this->scale, 0, $label, 0, 0, '', false, $markerlink);
+                $this->MultiCell(0, 0, $comment->rawtext, 0, 'L');
+                $this->Ln(12 * $this->scale);
+            }
+            // Add an extra line break between pages.
+            $this->Ln(12 * $this->scale);
+        }
+
+        return $commentlinks;
+    }
+
+    /**
+     * Add a comment marker to the specified page.
+     *
+     * @param int $pageno The page number to add markers to (starting at 0).
+     * @param int $index The comment index.
+     * @param int $x The x-coordinate of the marker (in pixels).
+     * @param int $y The y-coordinate of the marker (in pixels).
+     * @param int $link The link identifier pointing to the full comment text.
+     * @param string $colour The fill colour of the marker (red, yellow, green, blue, white, clear).
+     * @return bool Success status.
+     */
+    public function add_comment_marker($pageno, $index, $x, $y, $link, $colour = 'yellow') {
+        if (!$this->filename) {
+            return false;
+        }
+
+        $fill = '';
+        $fillopacity = 0.9;
+        switch ($colour) {
+            case 'red':
+                $fill = 'rgb(249, 181, 179)';
+                break;
+            case 'green':
+                $fill = 'rgb(214, 234, 178)';
+                break;
+            case 'blue':
+                $fill = 'rgb(203, 217, 237)';
+                break;
+            case 'white':
+                $fill = 'rgb(255, 255, 255)';
+                break;
+            case 'clear':
+                $fillopacity = 0;
+                break;
+            default: /* Yellow */
+                $fill = 'rgb(255, 236, 174)';
+        }
+        $marker = '@<svg xmlns="http://www.w3.org/2000/svg" viewBox="-0.5 -0.5 12 12" preserveAspectRatio="xMinYMin meet">' .
+                '<path d="M11 0H1C.4 0 0 .4 0 1v6c0 .6.4 1 1 1h1v4l4-4h5c.6 0 1-.4 1-1V1c0-.6-.4-1-1-1z" fill="' . $fill . '" ' .
+                'fill-opacity="' . $fillopacity . '" stroke="rgb(153, 153, 153)" stroke-width="0.5"/></svg>';
+        $label = get_string('commentlabel', 'assignfeedback_editpdf', array('pnum' => $pageno + 1, 'cnum' => $index + 1));
+
+        $x *= $this->scale;
+        $y *= $this->scale;
+        $size = 24 * $this->scale;
+        $this->SetDrawColor(51, 51, 51);
+        $this->SetFontSize(10 * $this->scale);
+        $this->setPage($pageno + 1);
+
+        // Add the marker image.
+        $this->ImageSVG($marker, $x - 0.5, $y - 0.5, $size, $size, $link);
+
+        // Add the label.
+        $this->MultiCell($size * 0.95, 0, $label, 0, 'C', false, 1, $x, $y, true, 0, false, true, $size * 0.60, 'M', true);
+
+        return true;
+    }
+
     /**
      * Add a comment to the current page
      * @param string $text the text of the comment

mod/assign/feedback/editpdf/lang/en/assignfeedback_editpdf.php

@@ -33,6 +33,8 @@ $string['clear'] = 'Clear';
 $string['colourpicker'] = 'Colour picker';
 $string['commentcolour'] = 'Comment colour';
 $string['comment'] = 'Comments';
+$string['commentindex'] = 'Index of comments';
+$string['commentlabel'] = '{$a->pnum}.{$a->cnum}';
 $string['command'] = 'Command:';
 $string['commentcontextmenu'] = 'Comment context menu';
 $string['couldnotsavepage'] = 'Could not save page {$a}';