Improved overview, now allows deleting and shows more info.

Thanks very much for Thomas Robb for submitting the original
modification with the new functionality ... I ended up doing a
lot of cleaning up and reworking of it but it wouldn't have been
done without Thom's work.

mod/quiz/report/overview/report.php

@@ -1,20 +1,71 @@
-<?PHP  // $Id$
+<?php  // $Id$
 
 /// Overview report just displays a big table of all the attempts
 
 class quiz_report extends quiz_default_report {
 
     function display($quiz, $cm, $course) {     /// This function just displays the report
 
-        global $CFG, $QUIZ_GRADE_METHOD;
-
-        if (!$grades = quiz_get_grade_records($quiz)) {
-            return;
-        }
+        global $CFG, $QUIZ_GRADE_METHOD, $del;
 
+        $strreallydel = addslashes(get_string('deleteattemptcheck','quiz'));
+        $strdeleteselected = get_string('deleteselected');
+        $strdeleteall = get_string('deleteall');
         $strname  = get_string("name");
         $strattempts  = get_string("attempts", "quiz");
+        $strnoattempts = get_string('noattempts','quiz');
         $strbestgrade  = $QUIZ_GRADE_METHOD[$quiz->grademethod];
+        $strtimeformat = get_string('strftimedatetime');
+
+
+        if (!empty($del)) {   /// Some attempts need to be deleted
+
+            if (record_exists('quiz_attempts', 'quiz', $quiz->id)) {
+
+                if ($del == 'all'){     /// Delete all the attempts
+                    $attempts = get_records('quiz_attempts','quiz',$quiz->id);
+                    delete_records('quiz_attempts','quiz',$quiz->id);
+                    delete_records('quiz_grades','quiz',$quiz->id);
+                    if ($attempts) {
+                        foreach ($attempts as $thisattempt){
+                            delete_records('quiz_responses','attempt',$thisattempt->id);
+                        }
+                    }
+
+                } else {                /// Delete selected attempts
+
+                    $items = (array)data_submitted();
+
+                    unset($items['del']);
+                    unset($items['id']);
+
+                    if ($items) {
+                        foreach ($items as $attemptid) {
+                            if ($todelete = get_record('quiz_attempts', 'id', $attemptid)) {
+                                delete_records('quiz_attempts', 'id', $attemptid);
+                                delete_records('quiz_responses', 'attempt', $attemptid);
+
+                                // Search quiz_attempts for other instances by this user.  
+                                // If none, then delete record for this quiz, this user from quiz_grades 
+                                // else recalculate best grade
+
+                                $userid = $todelete->userid;
+                                if (!record_exists('quiz_attempts', 'userid', $userid, 'quiz',$quiz->id)) {
+                                    delete_records('quiz_grades', 'userid', $userid,'quiz',$quiz->id);
+                                } else {
+                                    quiz_save_best_grade($quiz, $userid);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        if (!$grades = quiz_get_grade_records($quiz)) {
+            print_heading($strnoattempts);
+            return true;
+        }
 
         $table->head = array("&nbsp;", $strname, $strattempts, "$strbestgrade /$quiz->grade");
         $table->align = array("center", "left", "left", "center");
@@ -24,21 +75,69 @@ function display($quiz, $cm, $course) {     /// This function just displays the
 
         foreach ($grades as $grade) {
             $picture = print_user_picture($grade->userid, $course->id, $grade->picture, false, true);
-    
+
             if ($attempts = quiz_get_user_attempts($quiz->id, $grade->userid)) {
-                $userattempts = quiz_get_user_attempts_string($quiz, $attempts, $grade->grade);
+                $userattempts = $this->quiz_get_user_attempts_list($quiz, $attempts, $grade->grade, $strtimeformat);
+            } else {
+                $userattempts = "";
             }
-    
+
             $table->data[] = array ($picture, 
                                     "<a href=\"$CFG->wwwroot/user/view.php?id=$grade->userid&course=$course->id\">".
                                     "$grade->firstname $grade->lastname</a>", 
                                     "$userattempts", round($grade->grade,0));
         }
-
+
+        //Embed script for warning
+        echo "\n<script lang=javascript>\n<!--\nfunction delcheck(){\n ";
+        echo "if (confirm('$strreallydel')) {\n";
+        echo " document.delform.del.value='all';\n return true;\n";
+        echo " } else {\n";
+        echo " return false;\n }\n}\n";
+        echo "//-->\n</script>\n";
+
+        $onsub = "return confirm('$strreallydel')";
+
+        echo "<form method=\"post\" action=\"report.php\" name=\"delform\" onsubmit=\"$onsub\">\n";
+        echo "<input type=\"hidden\" name=\"del\" value=\"selection\">\n";
+        echo "<input type=\"hidden\" name=\"id\" value=\"$cm->id\">\n";
+
         print_table($table);
+
+        //There might be a more elegant way than using the <center> tag for this
+        echo "<center><input type=\"submit\" value=\"$strdeleteselected\">&nbsp;";
+        echo "<input type=button value=\"$strdeleteall\" onClick=\"if(delcheck()){document.delform.submit()}\">\n</center>\n";
+        echo "</form>\n";
 
         return true;
     }
+
+    function quiz_get_user_attempts_list($quiz, $attempts, $bestgrade, $timeformat) {
+    /// Returns a little list of all attempts, one per line, 
+    /// with each grade linked to the feedback report and with the best grade highlighted
+    /// Each also has information about date and lapsed time
+
+        $bestgrade = format_float($bestgrade);
+
+        foreach ($attempts as $attempt) {
+            $attemptgrade = format_float(($attempt->sumgrades / $quiz->sumgrades) * $quiz->grade);
+            $attemptdate = userdate($attempt->timestart, $timeformat);
+            if ($attempt->timefinish) {
+                $attemptlapse = date("I:s", $attempt->timefinish - $attempt->timestart);
+            } else {
+                $attemptlapse = "...";
+            }
+            $button = "<input type=checkbox name=\"box$attempt->id\" value=\"$attempt->id\">";
+            $revurl = "review.php?q=$quiz->id&attempt=$attempt->id";
+            if ($attemptgrade == $bestgrade) {
+                $userattempts[] = "$button&nbsp;<span class=highlight><a href=\"$revurl\">$attemptgrade</a></span>&nbsp;$attemptdate&nbsp;($attemptlapse)";
+            } else {
+                $userattempts[] = "$button&nbsp;<a href=\"$revurl\">$attemptgrade</a>&nbsp;$attemptdate&nbsp;($attemptlapse)";
+            }
+        }
+        return implode("<br />\n", $userattempts);
+    }
+
 }
 
 ?>