[baseconfig] Overhaul hook system

This enables us to finally properly show the inheritance flow
of all the config variables when editing the baseconfig for
a certain location or machine.

15 files changed, 449 insertions, 280 deletions

diff --git a/modules-available/baseconfig/api.inc.php b/modules-available/baseconfig/api.inc.php
index aab03b5a..350c6173 100644
--- a/modules-available/baseconfig/api.inc.php
+++ b/modules-available/baseconfig/api.inc.php
@@ -1,125 +1,5 @@
 <?php
 
-$ip = $_SERVER['REMOTE_ADDR'];
-if (substr($ip, 0, 7) === '::ffff:') {
-	$ip = substr($ip, 7);
-}
-
-$uuid = Request::any('uuid', false, 'string');
-if ($uuid !== false && strlen($uuid) !== 36) {
-	$uuid = false;
-}
-
-class ConfigHolder
-{
-	private static $config = [];
-
-	private static $context = '';
-
-	private static $postHooks = [];
-
-	public static function setContext($name)
-	{
-		self::$context = $name;
-	}
-
-	public static function addArray($array, $prio = 0)
-	{
-		foreach ($array as $key => $value) {
-			self::add($key, $value, $prio);
-		}
-	}
-
-	public static function add($key, $value, $prio = 0)
-	{
-		if (!isset(self::$config[$key])) {
-			self::$config[$key] = [];
-		}
-		$new = [
-			'prio' => $prio,
-			'value' => $value,
-			'context' => self::$context,
-		];
-		if (empty(self::$config[$key]) || self::$config[$key][0]['prio'] > $prio) {
-			// Existing is higher, append new one
-			array_push(self::$config[$key], $new);
-		} else {
-			// New one has highest prio or matches existing, put in front
-			array_unshift(self::$config[$key], $new);
-		}
-	}
-
-	public static function get($key)
-	{
-		if (!isset(self::$config[$key]))
-			return false;
-		return self::$config[$key][0]['value'];
-	}
-
-	/**
-	 * @param callable $func
-	 */
-	public static function addPostHook($func)
-	{
-		self::$postHooks[] = array('context' => self::$context, 'function' => $func);
-	}
-
-	public static function applyPostHooks()
-	{
-		foreach (self::$postHooks as $hook) {
-			self::$context = $hook['context'] . ':post';
-			$hook['function']();
-		}
-		self::$postHooks = [];
-	}
-
-	public static function getConfig()
-	{
-		self::applyPostHooks();
-		$ret = [];
-		foreach (self::$config as $key => $list) {
-			if ($list[0]['value'] === false)
-				continue;
-			$ret[$key] = $list[0]['value'];
-		}
-		return $ret;
-	}
-
-	public static function outputConfig()
-	{
-		self::applyPostHooks();
-		foreach (self::$config as $key => $list) {
-			echo str_pad('# ' . $key . ' ', 35, '#', STR_PAD_BOTH), "\n";
-			foreach ($list as $pos => $item) {
-				if ($pos != 0 || $item['value'] === false) {
-					echo '# (', $item['context'], ':', $item['prio'], ')';
-					if ($pos == 0) {
-						echo " <disabled this setting>\n";
-					} else {
-						echo " <overridden>\n";
-					}
-				} else {
-					echo $key, "='", escape($item['value']), "'\n";
-					echo '# (', $item['context'], ':', $item['prio'], ") <active>\n";
-				}
-			}
-		}
-	}
-
-}
-
-/**
- * Escape given string so it is a valid string in sh that can be surrounded
- * by single quotes ('). This basically turns _'_ into _'"'"'_
- *
- * @param string $string input
- * @return string escaped sh string
- */
-function escape($string)
-{
-	return str_replace("'", "'\"'\"'", $string);
-}
-
 /*
  * We gather all config variables here. First, let other modules generate
  * their desired config vars. Afterwards, add the global config vars from
@@ -127,58 +7,19 @@ function escape($string)
  * global setting.
  */
 
-function handleModule($name, $ip, $uuid) // Pass ip and uuid instead of global to make them read only
-{
-	// Module has getconfig hook
-	$file = 'modules/' . $name . '/baseconfig/getconfig.inc.php';
-	if (!is_file($file))
-		return;
-	// Properly registered and can be activated
-	$mod = Module::get($name);
-	if ($mod === false)
-		return;
-	if (!$mod->activate(1, false))
-		return;
-	// Process dependencies first
-	foreach ($mod->getDependencies() as $dep) {
-		handleModule($dep, $ip, $uuid);
-	}
-	ConfigHolder::setContext($name);
-	(function($file, $ip, $uuid) {
-		include_once($file);
-	})($file, $ip, $uuid);
-}
-
-// Handle any hooks by other modules first
-// other modules should generally only populate $configVars
-foreach (glob('modules/*/baseconfig/getconfig.inc.php') as $file) {
-	preg_match('#^modules/([^/]+)/#', $file, $out);
-	ConfigHolder::setContext($out[1]);
-	handleModule($out[1], $ip, $uuid);
-}
-
-// Rest is handled by module
-$defaults = BaseConfigUtil::getVariables();
 
-// Dump global config from DB
-ConfigHolder::setContext('<global>');
-$res = Database::simpleQuery('SELECT setting, value FROM setting_global');
-while ($row = $res->fetch(PDO::FETCH_ASSOC)) {
-	if (!isset($defaults[$row['setting']]))
-		continue; // Setting is not defined in any <module>/baseconfig/settings.json
-	ConfigHolder::add($row['setting'], $row['value'], -1);
-}
+// Prepare ConfigHolder from request data
+BaseConfig::prepareFromRequest();
 
-// Fallback to default values from json files
-ConfigHolder::setContext('<default>');
-foreach ($defaults as $setting => $value) {
-	ConfigHolder::add($setting, $value['defaultvalue'], -1000);
-}
+ConfigHolder::add('SLX_NOW', time(), PHP_INT_MAX);
 
 // All done, now output
-ConfigHolder::add('SLX_NOW', time(), PHP_INT_MAX);
+ConfigHolder::applyPostHooks();
 ConfigHolder::outputConfig();
 
 // For quick testing or custom extensions: Include external file that should do nothing
 // more than outputting more key-value-pairs. It's expected in the webroot of slxadmin
-if (file_exists('client_config_additional.php')) @include('client_config_additional.php');
+if (file_exists('client_config_additional.php')) {
+	echo "########## client_config_additional.php:\n";
+	@include('client_config_additional.php');
+}
diff --git a/modules-available/baseconfig/inc/baseconfig.inc.php b/modules-available/baseconfig/inc/baseconfig.inc.php
new file mode 100644
index 00000000..064e0f89
--- /dev/null
+++ b/modules-available/baseconfig/inc/baseconfig.inc.php
@@ -0,0 +1,148 @@
+<?php
+
+class BaseConfig
+{
+
+	private static $modulesDone = [];
+
+	/**
+	 * @var array key-value-pairs of override vars, can be accessed by hooks
+	 */
+	private static $overrides = [];
+
+	/**
+	 * Fill the ConfigHolder with values from various hooks, while taking
+	 * into account UUID and IP-address of the client making the current
+	 * HTTP request.
+	 */
+	public static function prepareFromRequest()
+	{
+		$ip = $_SERVER['REMOTE_ADDR'];
+		if (substr($ip, 0, 7) === '::ffff:') {
+			$ip = substr($ip, 7);
+		}
+		$uuid = Request::any('uuid', false, 'string');
+		if ($uuid !== false && strlen($uuid) !== 36) {
+			$uuid = false;
+		}
+		// Handle any hooks by other modules first
+		// other modules should generally only populate $configVars
+		foreach (glob('modules/*/baseconfig/getconfig.inc.php') as $file) {
+			preg_match('#^modules/([^/]+)/#', $file, $out);
+			ConfigHolder::setContext($out[1]);
+			self::handleModule($out[1], $ip, $uuid, false);
+		}
+		self::commonBase();
+	}
+
+	/**
+	 * Fill the ConfigHolder with data from various hooks that supply
+	 * static overrides for config variables. The overrides can be used
+	 * to make the hooks behave in certain ways, by setting specific values like
+	 * 'locationid'
+	 * @param array $overrides key value pairs of overrides
+	 */
+	public static function prepareWithOverrides($overrides)
+	{
+		self::$overrides = $overrides;
+		$ip = $uuid = false;
+		if (self::hasOverride('ip')) {
+			$ip = self::getOverride('ip');
+		}
+		if (self::hasOverride('uuid')) {
+			$uuid = self::getOverride('uuid');
+		}
+		// Handle only static hooks that don't dynamically generate output
+		foreach (glob('modules/*/baseconfig/hook.json') as $file) {
+			preg_match('#^modules/([^/]+)/#', $file, $out);
+			ConfigHolder::setContext($out[1]);
+			self::handleModule($out[1], $ip, $uuid, true);
+		}
+		self::commonBase();
+	}
+
+	/**
+	 * Just fill the ConfigHolder with the defaults from all the json files
+	 * that define config variables.
+	 */
+	public static function prepareDefaults()
+	{
+		$defaults = BaseConfigUtil::getVariables();
+		self::addDefaults($defaults);
+	}
+
+	private static function commonBase()
+	{
+		$defaults = BaseConfigUtil::getVariables();
+
+		// Dump global config from DB
+		ConfigHolder::setContext('<global>', function($id) {
+			return [
+				'name' => Dictionary::translate('source-global', true),
+				'locationid' => 0,
+			];
+		});
+		$res = Database::simpleQuery('SELECT setting, value, displayvalue FROM setting_global');
+		while ($row = $res->fetch(PDO::FETCH_ASSOC)) {
+			if (!isset($defaults[$row['setting']]))
+				continue; // Setting is not defined in any <module>/baseconfig/settings.json
+			ConfigHolder::add($row['setting'], $row, -1);
+		}
+
+		// Fallback to default values from json files
+		self::addDefaults($defaults);
+
+	}
+
+	private static function addDefaults($defaults)
+	{
+		ConfigHolder::setContext('<default>', function($id) {
+			return [
+				'name' => Dictionary::translate('source-default', true),
+				'locationid' => 0,
+			];
+		});
+		foreach ($defaults as $setting => $value) {
+			ConfigHolder::add($setting, $value['defaultvalue'], -1000);
+		}
+	}
+
+	private static function handleModule($name, $ip, $uuid, $needJsonHook) // Pass ip and uuid instead of global to make them read only
+	{
+		if (isset(self::$modulesDone[$name]))
+			return;
+		self::$modulesDone[$name] = true;
+		// Module has getconfig hook
+		$file = 'modules/' . $name . '/baseconfig/getconfig.inc.php';
+		if (!is_file($file))
+			return;
+		// We want only static hooks that have a json config (currently used for displaying inheritance tree)
+		if ($needJsonHook && !is_file('modules/' . $name . '/baseconfig/hook.json'))
+			return;
+		// Properly registered and can be activated
+		$mod = Module::get($name);
+		if ($mod === false)
+			return;
+		if (!$mod->activate(1, false))
+			return;
+		// Process dependencies first
+		foreach ($mod->getDependencies() as $dep) {
+			self::handleModule($dep, $ip, $uuid, $needJsonHook);
+		}
+		ConfigHolder::setContext($name);
+		(function ($file, $ip, $uuid) {
+			include_once($file);
+		})($file, $ip, $uuid);
+	}
+
+	public static function hasOverride($key)
+	{
+		return array_key_exists($key, self::$overrides);
+	}
+
+	public static function getOverride($key)
+	{
+		return self::$overrides[$key];
+	}
+
+}
\ No newline at end of file
diff --git a/modules-available/baseconfig/inc/configholder.inc.php b/modules-available/baseconfig/inc/configholder.inc.php
new file mode 100644
index 00000000..e5856128
--- /dev/null
+++ b/modules-available/baseconfig/inc/configholder.inc.php
@@ -0,0 +1,137 @@
+<?php
+
+class ConfigHolder
+{
+	private static $config = [];
+
+	private static $context = '';
+
+	private static $postHooks = [];
+
+	public static function setContext($id, $resolver = false)
+	{
+		$tmp = ['id' => $id, 'resolver' => $resolver];
+		self::$context =& $tmp;
+	}
+
+	/**
+	 * @param string $key config variable name
+	 * @param false|string|array $value false to unset, string value, or array with keys value and displayvalue
+	 * @param int $prio priority of this value, in case the same key gets set multiple times
+	 */
+	public static function add($key, $value, $prio = 0)
+	{
+		if (!isset(self::$config[$key])) {
+			self::$config[$key] = [];
+		}
+		$new = [
+			'prio' => $prio,
+			'context' => &self::$context,
+		];
+		if (is_array($value)) {
+			$new['value'] = $value['value'];
+			$new['displayvalue'] = $value['displayvalue'];
+		} else {
+			$new['value'] = $value;
+		}
+		if (empty(self::$config[$key]) || self::$config[$key][0]['prio'] > $prio) {
+			// Existing is higher, append new one
+			array_push(self::$config[$key], $new);
+		} else {
+			// New one has highest prio or matches existing, put in front
+			array_unshift(self::$config[$key], $new);
+		}
+	}
+
+	public static function get($key)
+	{
+		if (!isset(self::$config[$key]))
+			return false;
+		return self::$config[$key][0]['value'];
+	}
+
+	/**
+	 * @param callable $func
+	 */
+	public static function addPostHook($func)
+	{
+		self::$postHooks[] = array('context' => &self::$context, 'function' => $func);
+	}
+
+	public static function applyPostHooks()
+	{
+		foreach (self::$postHooks as $hook) {
+			$newContext = $hook['context'];
+			$newContext['post'] = true;
+			self::$context =& $newContext;
+			$hook['function']();
+		}
+		self::$postHooks = [];
+	}
+
+	public static function getRecursiveConfig($prettyPrint = true)
+	{
+		$ret = [];
+		foreach (self::$config as $key => $list) {
+			$last = false;
+			foreach ($list as $entry) {
+				if ($last !== false && $last['context']['id'] === '<global>'
+						&& $entry['context']['id'] === '<default>' && $last['value'] === $entry['value'])
+					continue;
+				$cb =& $entry['context']['resolver'];
+				$valueKey = 'value';
+				if ($prettyPrint && is_callable($cb)) {
+					$data = $cb($entry['context']['id']);
+					$name = $data['name'];
+					if (isset($data['locationid']) && isset($entry['displayvalue'])
+							&& User::hasPermission('.baseconfig.view', $data['locationid'])) {
+						$valueKey = 'displayvalue';
+					}
+				} else {
+					$name = $entry['context']['id'];
+				}
+				$ret[$key][] = ['name' => $name, 'value' => $entry[$valueKey]];
+				$last = $entry;
+			}
+		}
+		return $ret;
+	}
+
+	public static function outputConfig()
+	{
+		foreach (self::$config as $key => $list) {
+			echo str_pad('# ' . $key . ' ', 35, '#', STR_PAD_BOTH), "\n";
+			foreach ($list as $pos => $item) {
+				$ctx = $item['context']['id'];
+				if (isset($item['context']['post'])) {
+					$ctx .= '[post-hook]';
+				}
+				$ctx .= ' :: ' . $item['prio'];
+				if ($pos != 0 || $item['value'] === false) {
+					echo '# (', $ctx, ')';
+					if ($pos == 0) {
+						echo " <disabled this setting>\n";
+					} else {
+						echo " <overridden>\n";
+					}
+				} else {
+					echo $key, "='", self::escape($item['value']), "'\n";
+					echo '# (', $ctx, ") <active>\n";
+				}
+			}
+		}
+	}
+
+	/**
+	 * Escape given string so it is a valid string in sh that can be surrounded
+	 * by single quotes ('). This basically turns _'_ into _'"'"'_
+	 *
+	 * @param string $string input
+	 * @return string escaped sh string
+	 */
+	private static function escape($string)
+	{
+		return str_replace("'", "'\"'\"'", $string);
+	}
+
+}
diff --git a/modules-available/baseconfig/lang/de/module.json b/modules-available/baseconfig/lang/de/module.json
index 44b51ec3..f7dbf53a 100644
--- a/modules-available/baseconfig/lang/de/module.json
+++ b/modules-available/baseconfig/lang/de/module.json
@@ -1,3 +1,5 @@
 {
-    "module_name": "Konfigurationsvariablen"
+    "module_name": "Konfigurationsvariablen",
+    "source-default": "Auslieferungszustand",
+    "source-global": "Global"
 }
\ No newline at end of file
diff --git a/modules-available/baseconfig/lang/de/template-tags.json b/modules-available/baseconfig/lang/de/template-tags.json
index dfaecc96..1ce62c87 100644
--- a/modules-available/baseconfig/lang/de/template-tags.json
+++ b/modules-available/baseconfig/lang/de/template-tags.json
@@ -1,8 +1,7 @@
 {
     "lang_basicConfiguration": "Basiskonfiguration",
     "lang_clientRelatedConfig": "Die Optionen auf dieser Seite beziehen sich auf das Verhalten der bwLehrpool-Clients.",
-    "lang_defaultValue": "Standard",
     "lang_editOverrideNotice": "Sie bearbeiten die Einstellungen f\u00fcr einen Unterbereich",
     "lang_enableOverride": "\u00dcberschreiben",
-    "lang_inheritSource": "Geerbt von"
+    "lang_showParents": "Geerbte Werte"
 }
\ No newline at end of file
diff --git a/modules-available/baseconfig/lang/en/module.json b/modules-available/baseconfig/lang/en/module.json
index 9ad9d10f..97e19f92 100644
--- a/modules-available/baseconfig/lang/en/module.json
+++ b/modules-available/baseconfig/lang/en/module.json
@@ -1,3 +1,5 @@
 {
-    "module_name": "Config Variables"
+    "module_name": "Config Variables",
+    "source-default": "Factory default",
+    "source-global": "Global"
 }
\ No newline at end of file
diff --git a/modules-available/baseconfig/lang/en/template-tags.json b/modules-available/baseconfig/lang/en/template-tags.json
index 471fef35..9ac578e7 100644
--- a/modules-available/baseconfig/lang/en/template-tags.json
+++ b/modules-available/baseconfig/lang/en/template-tags.json
@@ -1,8 +1,7 @@
 {
     "lang_basicConfiguration": "Basic Configuration",
     "lang_clientRelatedConfig": "The options on this page are related to the bwLehrpool client machines.",
-    "lang_defaultValue": "Default",
     "lang_editOverrideNotice": "You're editing the settings of a sub-section",
     "lang_enableOverride": "Override",
-    "lang_inheritSource": "Inherited from"
+    "lang_showParents": "Inherited values"
 }
\ No newline at end of file
diff --git a/modules-available/baseconfig/page.inc.php b/modules-available/baseconfig/page.inc.php
index 0c11d5e1..a931d3f3 100644
--- a/modules-available/baseconfig/page.inc.php
+++ b/modules-available/baseconfig/page.inc.php
@@ -127,59 +127,47 @@ class Page_BaseConfig extends Page
 			$where = '';
 			$params = array();
 		}
+		$parents = $this->getInheritanceData();
 		// List config options
 		$settings = array();
-		$vars = BaseConfigUtil::getVariables();
+		$varsFromJson = BaseConfigUtil::getVariables();
 		// Remember missing variables
-		$missing = $vars;
+		$missing = $varsFromJson;
 		// Populate structure with existing config from db
-		$this->fillSettings($vars, $settings, $missing, $this->qry_extra['table'], $fields, $where, $params, false);
-		if (isset($this->qry_extra['getfallback']) && !empty($missing)) {
-			$method = explode('::', $this->qry_extra['getfallback']);
-			$fieldValue = $this->qry_extra['field_value'];
-			$tries = 0;
-			while (++$tries < 100 && !empty($missing)) {
-				$ret = call_user_func($method, $fieldValue);
-				if ($ret === false)
-					break;
-				$fieldValue = $ret['value'];
-				$params = array('field_value' => $fieldValue);
-				$this->fillSettings($vars, $settings, $missing, $this->qry_extra['table'], $fields, $where, $params, $ret['display']);
-			}
-		}
-		if ($this->targetModule !== false && !empty($missing)) {
-			$this->fillSettings($vars, $settings, $missing, 'setting_global', '', '', array(), 'Global');
-		}
+		$this->fillSettings($varsFromJson, $settings, $missing, $this->qry_extra['table'], $fields, $where, $params, false);
 		// Add entries that weren't in the db (global), setup override checkbox (module specific)
-		foreach ($vars as $key => $var) {
+		foreach ($varsFromJson as $key => $var) {
 			if ($this->targetModule !== false && !isset($settings[$var['catid']]['settings'][$key])) {
 				// Module specific - value is not set in DB
-				$settings[$var['catid']]['settings'][$key] = $var + array(
+				$settings[$var['catid']]['settings'][$key] = array(
 					'setting' => $key
 				);
 			}
-			if (!isset($settings[$var['catid']]['settings'][$key]['displayvalue'])) {
-				$settings[$var['catid']]['settings'][$key]['displayvalue'] = $var['defaultvalue'];
-			}
-			if (!isset($settings[$var['catid']]['settings'][$key]['defaultvalue'])) {
-				$settings[$var['catid']]['settings'][$key]['defaultvalue'] = $var['defaultvalue'];
+			$entry =& $settings[$var['catid']]['settings'][$key];
+			if (!isset($entry['displayvalue'])) {
+				if (isset($parents[$key][0]['value'])) {
+					$entry['displayvalue'] = $parents[$key][0]['value'];
+				} else {
+					$entry['displayvalue'] = $var['defaultvalue'];
+				}
 			}
-			if (!isset($settings[$var['catid']]['settings'][$key]['shadows'])) {
-				$settings[$var['catid']]['settings'][$key]['shadows'] = isset($var['shadows']) ? $var['shadows'] : null;
+			if (!isset($entry['shadows'])) {
+				$entry['shadows'] = isset($var['shadows']) ? $var['shadows'] : null;
 			}
-			$settings[$var['catid']]['settings'][$key] += array(
+			$entry += array(
 				'item' => $this->makeInput(
 					$var['validator'],
 					$key,
-					$settings[$var['catid']]['settings'][$key]['displayvalue'],
-					$settings[$var['catid']]['settings'][$key]['shadows'],
+					$entry['displayvalue'],
+					$entry['shadows'],
 					$editForbidden
 				),
 				'description' => Util::markup(Dictionary::translateFileModule($var['module'], 'config-variables', $key)),
 				'setting' => $key,
+				'tree' => isset($parents[$key]) ? $parents[$key] : false,
 			);
 		}
-		//die();
+		unset($entry);
 
 
 		// Sort categories
@@ -216,10 +204,7 @@ class Page_BaseConfig extends Page
 				continue;
 			}
 			unset($missing[$row['setting']]);
-			if ($sourceName !== false) {
-				$row['defaultvalue'] = '';
-				$row['defaultsource'] = $sourceName;
-			} elseif ($this->targetModule !== false) {
+			if ($this->targetModule !== false) {
 				$row['checked'] = 'checked';
 			}
 			$row += $vars[$row['setting']];
@@ -280,6 +265,16 @@ class Page_BaseConfig extends Page
 		$func = explode('::', $this->qry_extra['locationResolver']);
 		return (int)call_user_func($func, $this->qry_extra['field_value']);
 	}
+
+	private function getInheritanceData()
+	{
+		if (!isset($this->qry_extra['getInheritance']) || !isset($this->qry_extra['field_value'])) {
+			BaseConfig::prepareDefaults();
+			return ConfigHolder::getRecursiveConfig(true);
+		}
+		$func = explode('::', $this->qry_extra['getInheritance']);
+		return call_user_func($func, $this->qry_extra['field_value']);
+	}
 	
 	/**
 	 * Create html snippet for setting, based on given validator
diff --git a/modules-available/baseconfig/templates/_page.html b/modules-available/baseconfig/templates/_page.html
index 7f7c33d0..1f9bcafb 100644
--- a/modules-available/baseconfig/templates/_page.html
+++ b/modules-available/baseconfig/templates/_page.html
@@ -18,52 +18,53 @@
 			<a name="category_{{category_id}}"></a>
 			{{category_name}}
 		</div>
-		<div class="panel-body">
-			<div class="list-group">
-				{{#settings}}
-				<div class="list-group-item">
-					<div class="row">
-						<div class="col-md-5 slx-cfg-toggle">
-							<div>{{setting}}</div>
-							<div class="slx-default">
-								{{#defaultvalue}}{{lang_defaultValue}}:{{/defaultvalue}}
-								{{defaultvalue}}
-							</div>
-							{{#override}}
-							<div class="checkbox">
-								<input name="override[{{setting}}]" class="override-cb" id="CB_{{setting}}" type="checkbox" {{checked}} {{edit_disabled}}>
-								<label for="CB_{{setting}}">
-									{{lang_enableOverride}}
-								</label>
-							</div>
-							{{/override}}
+		<div class="list-group">
+			{{#settings}}
+			<div class="list-group-item">
+				<div class="row">
+					<div class="col-md-5 slx-cfg-toggle">
+						<div>{{setting}}</div>
+						{{#override}}
+						<div class="checkbox">
+							<input name="override[{{setting}}]" class="override-cb" id="CB_{{setting}}" type="checkbox" {{checked}} {{edit_disabled}}>
+							<label for="CB_{{setting}}">
+								{{lang_enableOverride}}
+							</label>
 						</div>
-						<div class="col-md-5 config-container">
-							{{{item}}}
-							<div class="slx-default">
-								{{#defaultsource}}{{lang_inheritSource}}:{{/defaultsource}}
-								{{defaultsource}}
-							</div>
+						{{/override}}
+					</div>
+					<div class="col-md-5 config-container">
+						{{{item}}}
+						<div class="slx-default">
+							{{#tree.0}}
+							<a href="#tree-{{setting}}" data-toggle="collapse">{{lang_showParents}}</a>
+							<div class="hidden" id="default-{{setting}}">{{value}}</div>
+							{{/tree.0}}
 						</div>
-						<div class="col-md-2">
-							<a class="btn btn-default" data-toggle="modal" data-target="#help-{{setting}}"><span class="glyphicon glyphicon-question-sign"></span></a>
+						<div class="slx-default collapse text-nowrap" id="tree-{{setting}}">
+							{{#tree}}
+							<div class="slx-strike"><b>{{name}}</b>: {{value}}</div>
+							{{/tree}}
 						</div>
 					</div>
+					<div class="col-md-2">
+						<a class="btn btn-default" data-toggle="modal" data-target="#help-{{setting}}"><span class="glyphicon glyphicon-question-sign"></span></a>
+					</div>
 				</div>
-				<div class="modal fade" id="help-{{setting}}" tabindex="-1" role="dialog">
-					<div class="modal-dialog">
-						<div class="modal-content">
-							<div class="modal-header">
-								<button type="button" class="close" data-dismiss="modal">&times;</button>
-								<h4 class="modal-title"><b>{{setting}}</b></h4>
+			</div>
+			<div class="modal fade" id="help-{{setting}}" tabindex="-1" role="dialog">
+				<div class="modal-dialog">
+					<div class="modal-content">
+						<div class="modal-header">
+							<button type="button" class="close" data-dismiss="modal">&times;</button>
+							<h4 class="modal-title"><b>{{setting}}</b></h4>
 
-							</div>
-							<div class="modal-body">{{{description}}}</div>
 						</div>
+						<div class="modal-body">{{{description}}}</div>
 					</div>
 				</div>
-				{{/settings}}
 			</div>
+			{{/settings}}
 		</div>
 	</div>
 	{{/categories}}
@@ -135,25 +136,44 @@ document.addEventListener("DOMContentLoaded", function () {
 
 	var updateCheckbox = function() {
 		var id = '#CB_' + $(this).attr('id');
-		$(id).prop('checked', true);
+		var $cb = $(id).prop('checked', true);
+		if ($cb.length > 0) {
+			syncCheckbox.call($cb[0]);
+		}
+	};
+	var syncCheckbox = function() {
+		var setting = this.id.substr(3);
+		var $itm = $('#tree-' + setting + ' > div:first-child');
+		if (this.checked) {
+			$itm.addClass('slx-strike');
+		} else {
+			$itm.removeClass('slx-strike');
+		}
 	};
 	var $cont = $('.config-container');
 	$cont.find('select, input').on('change', updateCheckbox);
 	$cont.find('input').on('input', updateCheckbox);
 	$('.override-cb').on('change', function() {
-		if (this.checked) return;
-		var input = document.getElementById(this.id.substr(3));
+		var setting = this.id.substr(3);
+		syncCheckbox.call(this);
+		var input = document.getElementById(setting);
 		if (!input) return;
+		var defaults = this.checked ? false : ('' + $('#default-' + setting).text());
 		if (input.tagName.toUpperCase() === 'SELECT') {
+			var items = defaults === false ? false : defaults.split(/\s+/);
 			$(input).find('option').each(function() {
-				$(this).prop('selected', this.defaultSelected);
+				$(this).prop('selected', items === false ? this.defaultSelected : (items.indexOf(this.value) !== -1));
 			});
 			$(input).filter('.multilist').multiselect('refresh');
 		} else if (input.type && input.type.toUpperCase() === 'CHECKBOX') {
-			$(input).prop('checked', input.defaultChecked);
-		} else if (input.defaultValue !== undefined) {
-			$(input).val(input.defaultValue);
-		}
+			$(input).prop('checked', defaults === false ? input.defaultChecked : !!defaults);
+		} else {
+			$(input).val(defaults === false ? input.defaultValue : defaults);
+		} // TODO: Make this work for multiinput/selectize (or get rid of them)
+		$allShadowingFields.each(updateShadows);
+	}).each(syncCheckbox);
+	window.addEventListener('unload', function() {
+		$('.multilist').multiselect('refresh');
 	});
 });
 </script>
diff --git a/modules-available/locations/baseconfig/getconfig.inc.php b/modules-available/locations/baseconfig/getconfig.inc.php
index f21503f1..26e43ed8 100644
--- a/modules-available/locations/baseconfig/getconfig.inc.php
+++ b/modules-available/locations/baseconfig/getconfig.inc.php
@@ -2,7 +2,9 @@
 
 // Location handling: figure out location
 $locationId = false;
-if (Request::any('force', 0, 'int') === 1 && Request::any('module', false, 'string') === 'locations') {
+if (BaseConfig::hasOverride('locationid')) {
+	$locationId = BaseConfig::getOverride('locationid');
+} elseif (Request::any('force', 0, 'int') === 1 && Request::any('module', false, 'string') === 'locations') {
 	// Force location for testing, but require logged in admin
 	if (User::load()) {
 		$locationId = Request::any('value', 0, 'int');
@@ -10,6 +12,8 @@ if (Request::any('force', 0, 'int') === 1 && Request::any('module', false, 'stri
 }
 
 if ($locationId === false) {
+	if (!$ip) // Required at this point, bail out if not given
+		return;
 	$locationId = Location::getFromIpAndUuid($ip, $uuid);
 }
 
@@ -23,19 +27,30 @@ if ($locationId !== false) {
 // Query location specific settings (from bottom to top)
 if (!empty($matchingLocations)) {
 	// First get all settings for all locations we're in
-	$list = implode(',', $matchingLocations);
-	$res = Database::simpleQuery("SELECT locationid, setting, value FROM setting_location WHERE locationid IN ($list)");
+	$res = Database::simpleQuery("SELECT locationid, setting, value, displayvalue
+			FROM setting_location WHERE locationid IN (:list)",
+		['list' => $matchingLocations]);
 	$tmp = array();
 	while ($row = $res->fetch(PDO::FETCH_ASSOC)) {
-		$tmp[(int)$row['locationid']][$row['setting']] = $row['value'];
+		$tmp[(int)$row['locationid']][$row['setting']] = $row; // Put whole row so we have value and displayvalue
 	}
+	// Callback for pretty printing
+	$cb = function($id) {
+		if (substr($id, 0, 9) !== 'location-')
+			return ['name' => $id, 'locationid' => 0];
+		$lid = (int)substr($id, 9);
+		return [
+			'name' => Location::getName($lid),
+			'locationid' => $lid,
+		];
+	};
 	// $matchingLocations contains the location ids sorted from closest to furthest, so we use it to make sure the order
 	// in which they override is correct (closest setting wins, e.g. room setting beats department setting)
 	$prio = count($matchingLocations) + 1;
 	foreach ($matchingLocations as $lid) {
 		if (!isset($tmp[$lid]))
 			continue;
-		ConfigHolder::setContext('location-' . $lid);
+		ConfigHolder::setContext('location-' . $lid, $cb);
 		foreach ($tmp[$lid] as $setting => $value) {
 			ConfigHolder::add($setting, $value, $prio);
 		}
diff --git a/modules-available/locations/baseconfig/hook.json b/modules-available/locations/baseconfig/hook.json
index 1d69647e..fabb4686 100644
--- a/modules-available/locations/baseconfig/hook.json
+++ b/modules-available/locations/baseconfig/hook.json
@@ -3,5 +3,5 @@
 	"field": "locationid",
 	"locationResolver": "LocationHooks::baseconfigLocationResolver",
 	"tostring": "Location::getName",
-	"getfallback": "LocationHooks::getBaseconfigParent"
+	"getInheritance": "LocationHooks::baseconfigInheritance"
 }
\ No newline at end of file
diff --git a/modules-available/locations/inc/locationhooks.inc.php b/modules-available/locations/inc/locationhooks.inc.php
index c15c34ab..5ce3bbfe 100644
--- a/modules-available/locations/inc/locationhooks.inc.php
+++ b/modules-available/locations/inc/locationhooks.inc.php
@@ -4,28 +4,26 @@ class LocationHooks
 {
 
 	/**
-	 * Used for baseconfig hook
-	 * @param $locationId
-	 * @return bool|array ('value' => x, 'display' => y), false if no parent or unknown id
+	 * Resolve baseconfig id to locationid -- noop in this case
 	 */
-	public static function getBaseconfigParent($locationId)
+	public static function baseconfigLocationResolver($id)
 	{
-		$locationId = (int)$locationId;
-		$assoc = Location::getLocationsAssoc();
-		if (!isset($assoc[$locationId]))
-			return false;
-		$locationId = (int)$assoc[$locationId]['parentlocationid'];
-		if (!isset($assoc[$locationId]))
-			return false;
-		return array('value' => $locationId, 'display' => $assoc[$locationId]['locationname']);
+		return $id;
 	}
 
 	/**
-	 * Resolve baseconfig id to locationid -- noop in this case
+	 * Hook to get inheritance tree for all config vars
+	 * @param int $id Locationid currently being edited
 	 */
-	public static function baseconfigLocationResolver($id)
+	public static function baseconfigInheritance($id)
 	{
-		return $id;
+		$locs = Location::getLocationsAssoc();
+		if ($locs === false || !isset($locs[$id]))
+			return [];
+		BaseConfig::prepareWithOverrides([
+			'locationid' => $locs[$id]['parentlocationid']
+		]);
+		return ConfigHolder::getRecursiveConfig(true);
 	}
 
 }
\ No newline at end of file
diff --git a/modules-available/statistics/baseconfig/getconfig.inc.php b/modules-available/statistics/baseconfig/getconfig.inc.php
index ea351d15..053827db 100644
--- a/modules-available/statistics/baseconfig/getconfig.inc.php
+++ b/modules-available/statistics/baseconfig/getconfig.inc.php
@@ -8,6 +8,9 @@ if (Request::any('force', 0, 'int') === 1 && Request::any('module', false, 'stri
 	}
 }
 
+if (!$uuid) // Required at this point, bail out if not given
+	return;
+
 // Query machine specific settings
 $res = Database::simpleQuery("SELECT setting, value FROM setting_machine WHERE machineuuid  = :uuid", ['uuid' => $uuid]);
 while ($row = $res->fetch(PDO::FETCH_ASSOC)) {
diff --git a/modules-available/statistics/baseconfig/hook.json b/modules-available/statistics/baseconfig/hook.json
index da28ad5d..4a406653 100644
--- a/modules-available/statistics/baseconfig/hook.json
+++ b/modules-available/statistics/baseconfig/hook.json
@@ -3,5 +3,5 @@
 	"field": "machineuuid",
 	"locationResolver": "StatisticsHooks::baseconfigLocationResolver",
 	"tostring": "StatisticsHooks::getBaseconfigName",
-	"getfallback": "StatisticsHooks::getBaseconfigParent"
+	"getInheritance": "StatisticsHooks::baseconfigInheritance"
 }
\ No newline at end of file
diff --git a/modules-available/statistics/inc/statisticshooks.inc.php b/modules-available/statistics/inc/statisticshooks.inc.php
index ead4917b..746bdabf 100644
--- a/modules-available/statistics/inc/statisticshooks.inc.php
+++ b/modules-available/statistics/inc/statisticshooks.inc.php
@@ -21,11 +21,6 @@ class StatisticsHooks
 		return self::$row['hostname'] ? self::$row['hostname'] : self::$row['clientip'];
 	}
 
-	public static function getBaseconfigParent($machineuuid)
-	{
-		return false; // TODO
-	}
-
 	public static function baseconfigLocationResolver($machineuuid)
 	{
 		self::getRow($machineuuid);
@@ -34,4 +29,19 @@ class StatisticsHooks
 		return (int)self::$row['locationid'];
 	}
 
+	/**
+	 * Hook to get inheritance tree for all config vars
+	 * @param int $machineuuid MachineUUID currently being edited
+	 */
+	public static function baseconfigInheritance($machineuuid)
+	{
+		self::getRow($machineuuid);
+		if (self::$row === false)
+			return [];
+		BaseConfig::prepareWithOverrides([
+			'locationid' => self::$row['locationid']
+		]);
+		return ConfigHolder::getRecursiveConfig(true);
+	}
+
 }
\ No newline at end of file