4 files changed, 106 insertions, 4 deletions

diff --git a/src/c/config.c b/src/c/config.c
new file mode 100644
index 0000000..1d3f3ac
--- /dev/null
+++ b/src/c/config.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2026 Reiner Herrmann
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "event.h"
+
+struct Configuration {
+	uint8_t version;
+	uint32_t enabled_extensions;
+} __attribute__((__packed__));
+
+#define SETTINGS_KEY 1
+#define CONFIG_VERSION 1
+#define NUM_EXTENSIONS 12
+
+static struct Configuration configuration;
+
+extern void reload_data();
+
+static void config_persist() {
+	persist_write_data(SETTINGS_KEY, &configuration, sizeof(configuration));
+
+	/* recalculate events based on updated configuration */
+	init_events();
+	reload_data();
+}
+
+static void config_load_defaults() {
+	configuration.version = CONFIG_VERSION;
+	configuration.enabled_extensions = 0xffffffff;
+}
+
+static void config_load() {
+	config_load_defaults();
+
+	/* buffer remains unchanged if no data is persisted */
+	persist_read_data(SETTINGS_KEY, &configuration, sizeof(configuration));
+
+	if (configuration.version != CONFIG_VERSION) {
+		/* unknown persisted configuration format */
+		config_load_defaults();
+	}
+}
+
+static void config_inbox_received_handler(DictionaryIterator *iter, void *context) {
+	uint32_t old_enabled_extensions = configuration.enabled_extensions;
+
+	for (int i=0; i<NUM_EXTENSIONS; i++) {
+		Tuple *enabled_extension = dict_find(iter, MESSAGE_KEY_enabled_extensions + i);
+		if (enabled_extension) {
+			bool val = enabled_extension->value->uint8;
+			/* clear bit */
+			configuration.enabled_extensions &= ~(1 << i);
+			/* set value into bit */
+			configuration.enabled_extensions |= (val << i);
+		}
+	}
+
+	if (old_enabled_extensions != configuration.enabled_extensions) {
+		/* only persist if something changed */
+		config_persist();
+	}
+}
+
+void config_init() {
+	config_load();
+
+	app_message_register_inbox_received(config_inbox_received_handler);
+	app_message_open(128, 128);
+}
+
+void config_deinit() {
+	app_message_deregister_callbacks();
+}
+
+uint32_t config_get_enabled_extensions() {
+	return configuration.enabled_extensions;
+}
diff --git a/src/c/config.h b/src/c/config.h
new file mode 100644
index 0000000..fcd21fb
--- /dev/null
+++ b/src/c/config.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) 2026 Reiner Herrmann
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#ifndef CONFIG_H
+#define CONFIG_H
+
+#include <pebble.h>
+
+void config_init();
+void config_deinit();
+uint32_t config_get_enabled_extensions();
+
+#endif
diff --git a/src/c/event.c b/src/c/event.c
index 36b0529..59fdb98 100644
--- a/src/c/event.c
+++ b/src/c/event.c
@@ -4,6 +4,7 @@
  */
 
 #include "event.h"
+#include "config.h"
 
 #define TIME2MIN(hh,mm) (hh * 60 + mm)
 
@@ -589,9 +590,8 @@ static struct Gw2Event *all_events = NULL;
 static int all_events_count = 0;
 static int event_index = 0;
 
-static inline uint16_t enabled_categories() {
-	/* TODO: make this mask configurable */
-	return 0xffff;
+static inline uint32_t enabled_categories() {
+	return config_get_enabled_extensions();
 }
 
 static inline bool is_category_enabled(enum Category category) {
diff --git a/src/c/gw2et.c b/src/c/gw2et.c
index e591868..42e67df 100644
--- a/src/c/gw2et.c
+++ b/src/c/gw2et.c
@@ -4,6 +4,7 @@
  */
 
 #include <pebble.h>
+#include "config.h"
 #include "event.h"
 
 #define DEFAULT_NUM_EVENTS 30
@@ -101,12 +102,18 @@ static void main_window_unload(Window *window) {
 	menu_layer_destroy(main_menu);
 }
 
+void reload_data() {
+	menu_layer_reload_data(main_menu);
+}
+
 static void tick_handler(struct tm *tick_time, TimeUnits units_changed) {
 	update_event_index();
-	menu_layer_reload_data(main_menu);
+	reload_data();
 }
 
 static void init() {
+	config_init();
+
 	main_window = window_create();
 	window_set_window_handlers(main_window, (WindowHandlers) {
 		.load = main_window_load,
@@ -119,6 +126,7 @@ static void init() {
 }
 
 static void deinit() {
+	config_deinit();
 	tick_timer_service_unsubscribe();
 	window_destroy(main_window);
 	cleanup_events();