feat: add factory reset on holding BOOT button

main/CMakeLists.txt

@@ -12,4 +12,6 @@ idf_component_register(
         ble_scanner
         mqtt_publisher
         led_indicator
+        driver
+        esp_driver_gpio
 )

main/Kconfig

@@ -0,0 +1,20 @@
+menu "Sensor Configuration"
+
+    config SENSOR_RESET_GPIO
+        int "Factory reset button GPIO number"
+        default 0
+        help
+            GPIO connected to the factory reset button. The pin is configured
+            with the internal pull-up enabled; connect the button between this
+            pin and GND (active-low). GPIO 0 is the BOOT button on standard
+            ESP32 DevKit boards and requires no extra hardware.
+
+    config SENSOR_RESET_HOLD_MS
+        int "Factory reset hold duration (ms)"
+        default 5000
+        range 1000 30000
+        help
+            How long the factory reset button must be held continuously before
+            a factory reset is triggered. Shorter presses are ignored.
+
+endmenu

main/main.c

@@ -9,9 +9,11 @@
 #include "esp_netif.h"
 #include "esp_log.h"
 #include "mdns.h"
+#include "driver/gpio.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/event_groups.h"
 #include "freertos/task.h"
+#include "driver/gpio.h"
 #include <stdio.h> 
 #include <string.h>
 
@@ -25,6 +27,37 @@
 
 static EventGroupHandle_t s_evt;
 
+static void reset_button_task(void *arg)
+{
+    gpio_config_t io_conf = {
+        .pin_bit_mask = 1ULL << CONFIG_SENSOR_RESET_GPIO,
+        .mode         = GPIO_MODE_INPUT,
+        .pull_up_en   = GPIO_PULLUP_ENABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type    = GPIO_INTR_DISABLE,
+    };
+    gpio_config(&io_conf);
+
+    TickType_t held_since = 0;
+    const TickType_t threshold = pdMS_TO_TICKS(CONFIG_SENSOR_RESET_HOLD_MS);
+
+    for (;;) {
+        if (gpio_get_level(CONFIG_SENSOR_RESET_GPIO) == 0) {
+            if (held_since == 0) held_since = xTaskGetTickCount();
+            if ((xTaskGetTickCount() - held_since) >= threshold) {
+                ESP_LOGI(TAG, "Reset button held %d ms — factory resetting", CONFIG_SENSOR_RESET_HOLD_MS);
+                led_indicator_set(LED_ERROR);
+                vTaskDelay(pdMS_TO_TICKS(500));
+                config_store_erase();
+                esp_restart();
+            }
+        } else {
+            held_since = 0;
+        }
+        vTaskDelay(pdMS_TO_TICKS(50));
+    }
+}
+
 static void wifi_event_handler(void *arg, esp_event_base_t base,
                                 int32_t id, void *data)
 {
@@ -103,6 +136,8 @@ void app_main(void)
     led_indicator_init();
     led_indicator_set(LED_CONNECTING);
 
+    xTaskCreate(reset_button_task, "reset_btn", 4096, NULL, 1, NULL);
+
     ESP_ERROR_CHECK(esp_netif_init());
     ESP_ERROR_CHECK(esp_event_loop_create_default());