From 8a1e7b7756db53d2b49a1ff202c2089d15229ca6 Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Mon, 30 Jul 2012 19:59:48 +0100
Subject: [PATCH] MDL-34640 quesion reponse files: PARTIAL SOLUTION to allowing
 resonse files to be graded automatically.

---
 question/engine/datalib.php             | 84 ++++++++++++++++++++++++-
 question/engine/questionattemptstep.php | 12 ++++
 2 files changed, 95 insertions(+), 1 deletion(-)

diff --git a/question/engine/datalib.php b/question/engine/datalib.php
index b58c05e0374..c742312c2ce 100644
--- a/question/engine/datalib.php
+++ b/question/engine/datalib.php
@@ -1199,6 +1199,21 @@ class question_engine_unit_of_work implements question_usage_observer {
 }
 
 
+/**
+ * The interface implemented by {@link question_file_saver} and {@link question_file_loader}.
+ *
+ * @copyright  2012 The Open University
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+interface question_response_files {
+    /**
+     * Get the files that were submitted.
+     * @return array of stored_files objects.
+     */
+    public function get_files();
+}
+
+
 /**
  * This class represents the promise to save some files from a particular draft
  * file area into a particular file area. It is used beause the necessary
@@ -1210,7 +1225,7 @@ class question_engine_unit_of_work implements question_usage_observer {
  * @copyright  2011 The Open University
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class question_file_saver {
+class question_file_saver implements question_response_files {
     /** @var int the id of the draft file area to save files from. */
     protected $draftitemid;
     /** @var string the owning component name. */
@@ -1290,6 +1305,73 @@ class question_file_saver {
         file_save_draft_area_files($this->draftitemid, $context->id,
                 $this->component, $this->filearea, $itemid);
     }
+
+    /**
+     * Get the files that were submitted.
+     * @return array of stored_files objects.
+     */
+    public function get_files() {
+        global $USER;
+
+        $fs = get_file_storage();
+        $usercontext = context_user::instance($USER->id);
+
+        return $fs->get_area_files($usercontext->id, 'user', 'draft',
+                $this->draftitemid, 'sortorder, filepath, filename', false);
+    }
+}
+
+
+/**
+ * This class is the mirror image of {@link question_file_saver}. It allows
+ * files to be accessed again later (e.g. when re-grading) using that same
+ * API as when doing the original grading.
+ *
+ * @copyright  2012 The Open University
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class question_file_loader implements question_response_files {
+    /** @var question_attempt_step the step that these files belong to. */
+    protected $step;
+
+    /** @var string the field name for these files - which is used to construct the file area name. */
+    protected $name;
+
+    /**
+    * @var string the value to stored in the question_attempt_step_data to
+     * represent these files.
+    */
+    protected $value;
+
+    /** @var int the context id that the files belong to. */
+    protected $contextid;
+
+    /**
+     * Constuctor.
+     * @param question_attempt_step $step the step that these files belong to.
+     * @param string $name string the field name for these files - which is used to construct the file area name.
+     * @param string $value the value to stored in the question_attempt_step_data to
+     *      represent these files.
+     * @param int $contextid the context id that the files belong to.
+     */
+    public function __construct(question_attempt_step $step, $name, $value, $contextid) {
+        $this->draftitemid = $draftitemid;
+        $this->component = $component;
+        $this->filearea = $filearea;
+        $this->value = $this->compute_value($draftitemid, $text);
+    }
+
+    public function __toString() {
+        return $this->value;
+    }
+
+    /**
+     * Get the files that were submitted.
+     * @return array of stored_files objects.
+     */
+    public function get_files() {
+        return $this->step->get_qt_files($this->name, $this->contextid);
+    }
 }
 
 
diff --git a/question/engine/questionattemptstep.php b/question/engine/questionattemptstep.php
index 5cbd5c8a65c..6145f4158bb 100644
--- a/question/engine/questionattemptstep.php
+++ b/question/engine/questionattemptstep.php
@@ -403,6 +403,18 @@ class question_attempt_step {
         if (!is_null($record->fraction)) {
             $step->fraction = $record->fraction + 0;
         }
+
+        // This next chunk of code requires getting $contextid and $qtype here.
+        // Somehow, we need to get that information to this point by modifying
+        // all the paths by which this method can be called.
+        foreach (question_bank::get_qtype($qtype)->response_file_areas() as $area) {
+            if (empty($step->data[$area])) {
+                continue;
+            }
+
+            $step->data[$area] = new question_file_loader($this, $area, $step->data[$area], $contextid)
+        }
+
         return $step;
     }
 }