Base institution.name value on the institution's display name

Bug 1518796

behatnotneeded: Covered by existing tests

Change-Id: I996e4562441140a6163dbf0b9dff4ee2894ffd83

htdocs/admin/users/institutions.php

@@ -653,26 +653,9 @@ EOF;
     exit;
 }
 
-// Generate random lower-case alpha-only institution name.
-function generate_institution_name() {
-    $i = substr(str_shuffle("abcdefghijklmnopqrstuvwxyz"), 0, 6);
-    if ($institution = get_record('institution', 'name', $i)) {
-        // try again
-        generate_institution_name();
-    }
-    else {
-        return $i;
-    }
-}
-
 function institution_validate(Pieform $form, $values) {
     global $USER, $institution, $add;
 
-    // Automatically generate institution name when adding new institution
-    if ($add) {
-        $institution = generate_institution_name();
-    }
-
     if ($USER->get('admin') || get_config_plugin('artefact', 'file', 'institutionaloverride')) {
         if (get_config_plugin('artefact', 'file', 'maxquotaenabled') && get_config_plugin('artefact', 'file', 'maxquota') < $values['defaultquota']) {
             $form->set_error('defaultquota', get_string('maxquotatoolow', 'artefact.file'));
@@ -724,6 +707,7 @@ function institution_submit(Pieform $form, $values) {
     db_begin();
     // Update the basic institution record...
     if ($add) {
+        $institution = generate_institution_name($values['displayname']);
         $newinstitution = new Institution();
         $newinstitution->initialise($institution, $values['displayname']);
         $institution = $newinstitution->name;

htdocs/lib/web.php

@@ -4432,6 +4432,41 @@ function generate_urlid($dirty, $default, $minlength=3, $maxlength=100) {
     return $s;
 }
 
+/**
+ * Generate a valid name for the institution.name column, based on the specified display name
+ *
+ * @param string $displayname
+ * @return string
+ */
+function generate_institution_name($displayname) {
+    // iconv can crash on strings that are too long, so truncate before converting
+    $basename = mb_substr($displayname, 0, 255);
+    $basename = iconv('UTF-8', 'ASCII//TRANSLIT', $displayname);
+    $basename = strtolower($basename);
+    $basename = preg_replace('/[^a-z]/', '', $basename);
+    if (strlen($basename) < 2) {
+        $basename = 'inst' . $basename;
+    }
+    else {
+        $basename = substr($basename, 0, 255);
+    }
+
+    // Make sure the name is unique. If it is not, add a suffix and see if
+    // that makes it unique
+    $finalname = $basename;
+    $suffix = 'a';
+    while (record_exists('institution', 'name', $finalname)) {
+        // Add the suffix but make sure the name length doesn't go over 255
+        $finalname = substr($basename, 0, 255 - strlen($suffix)) . $suffix;
+
+        // Will iterate a-z, aa-az, ba-bz, etc.
+        // See: http://php.net/manual/en/language.operators.increment.php
+        $suffix++;
+    }
+
+    return $finalname;
+}
+
 /**
  * Sorts an array by one of the value fields
  *