MDL-70565 user: filter course participants by country.

user/classes/output/participants_filter.php

@@ -24,6 +24,7 @@
 namespace core_user\output;
 
 use context_course;
+use core\user_fields;
 use renderable;
 use renderer_base;
 use stdClass;
@@ -89,6 +90,10 @@ class participants_filter implements renderable, templatable {
             $filtertypes[] = $filtertype;
         }
 
+        if ($filtertype = $this->get_country_filter()) {
+            $filtertypes[] = $filtertype;
+        }
+
         return $filtertypes;
     }
 
@@ -322,6 +327,34 @@ class participants_filter implements renderable, templatable {
         );
     }
 
+    /**
+     * Get data for the country filter
+     *
+     * @return stdClass|null
+     */
+    protected function get_country_filter(): ?stdClass {
+        $extrauserfields = user_fields::get_identity_fields($this->context, false);
+        if (array_search('country', $extrauserfields) === false) {
+            return null;
+        }
+
+        $countries = get_string_manager()->get_list_of_countries(true);
+
+        return $this->get_filter_object(
+            'country',
+            get_string('country'),
+            false,
+            true,
+            'core_user/local/participantsfilter/filtertypes/country',
+            array_map(function(string $code, string $name): stdClass {
+                return (object) [
+                    'value' => $code,
+                    'title' => $name,
+                ];
+            }, array_keys($countries), array_values($countries))
+        );
+    }
+
     /**
      * Get data for the keywords filter.
      *

user/classes/table/participants_filterset.php

@@ -27,7 +27,6 @@ declare(strict_types=1);
 
 namespace core_user\table;
 
-use core_table\local\filter\boolean_filter;
 use core_table\local\filter\filterset;
 use core_table\local\filter\integer_filter;
 use core_table\local\filter\string_filter;
@@ -61,6 +60,7 @@ class participants_filterset extends filterset {
      * - enrolments;
      * - groups;
      * - keywords;
+     * - country;
      * - roles; and
      * - status.
      *
@@ -72,6 +72,7 @@ class participants_filterset extends filterset {
             'enrolments' => integer_filter::class,
             'groups' => integer_filter::class,
             'keywords' => string_filter::class,
+            'country' => string_filter::class,
             'roles' => integer_filter::class,
             'status' => integer_filter::class,
         ];

user/classes/table/participants_search.php

@@ -257,6 +257,22 @@ class participants_search {
             }
         }
 
+        // Apply any country filtering.
+        if ($this->filterset->has_filter('country')) {
+            [
+                'where' => $countrywhere,
+                'params' => $countryparams,
+            ] = $this->get_country_sql();
+
+            if (!empty($countrywhere)) {
+                $wheres[] = "($countrywhere)";
+            }
+
+            if (!empty($countryparams)) {
+                $params = array_merge($params, $countryparams);
+            }
+        }
+
         // Apply any keyword text searches.
         if ($this->filterset->has_filter('keywords')) {
             [
@@ -877,6 +893,32 @@ class participants_search {
         ];
     }
 
+    /**
+     * Prepare SQL where clause and associated parameters for country filtering
+     *
+     * @return array SQL query data in the format ['where' => '', 'params' => []].
+     */
+    protected function get_country_sql(): array {
+        global $DB;
+
+        $where = '';
+        $params = [];
+
+        $countryfilter = $this->filterset->get_filter('country');
+        if ($countrycodes = $countryfilter->get_filter_values()) {
+            // If filter type is "None", then we negate the comparison.
+            [$countrywhere, $params] = $DB->get_in_or_equal($countrycodes, SQL_PARAMS_NAMED, 'country',
+                $countryfilter->get_join_type() !== $countryfilter::JOINTYPE_NONE);
+
+            $where = "(u.country {$countrywhere})";
+        }
+
+        return [
+            'where' => $where,
+            'params' => $params,
+        ];
+    }
+
     /**
      * Prepare SQL where clause and associated parameters for any keyword searches being performed.
      *
@@ -975,7 +1017,7 @@ class participants_search {
             $extrasearchfields = user_fields::get_identity_fields(null);
             foreach ($extrasearchfields as $fieldindex => $extrasearchfield) {
                 if (in_array($extrasearchfield, ['email', 'idnumber', 'country'])) {
-                    // Already covered above. Search by country not supported.
+                    // Already covered above.
                     continue;
                 }
                 // The param must be short (max 32 characters) so don't include field name.