Broke out services into their own files.

9 files changed, 400 insertions, 239 deletions

diff --git a/.gitignore b/.gitignore
index 44f40a2..6027692 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 sdkconfig
 sdkconfig.old
 build/*
+esp-homekit-intercom.code-workspace
diff --git a/main/CMakeLists.txt b/main/CMakeLists.txt
index 0e1f552..1237afe 100644
--- a/main/CMakeLists.txt
+++ b/main/CMakeLists.txt
@@ -1,4 +1,4 @@
 idf_component_register(
-    SRCS "app_main.c"
-    INCLUDE_DIRS ""
+    SRCS "src/event_queue.c" "src/lock.c" "src/bell.c" "app_main.c"
+    INCLUDE_DIRS "include"
 )
diff --git a/main/app_main.c b/main/app_main.c
index 1feb9dd..22e511f 100644
--- a/main/app_main.c
+++ b/main/app_main.c
@@ -18,7 +18,9 @@
 #include <app_wifi.h>
 #include <app_hap_setup_payload.h>
 
-static const char *TAG = "HAP Intercom";
+#include <lock.h>
+#include <bell.h>
+#include <event_queue.h>
 
 #define INTERCOM_TASK_PRIORITY 1
 #define INTERCOM_TASK_STACKSIZE 4 * 1024
@@ -26,90 +28,9 @@ static const char *TAG = "HAP Intercom";
 
 #define RESET_NETWORK_BUTTON_TIMEOUT 3
 
-#define INTERCOM_LOCK_GPIO_LOCKED 0
-#define INTERCOM_LOCK_GPIO_UNLOCKED 1
-
-#define HAP_LOCK_TARGET_STATE_UNSECURED 0
-#define HAP_LOCK_TARGET_STATE_SECURED 1
-static hap_val_t HAP_LOCK_CURRENT_STATE_UNSECURED = {.u = 0};
-static hap_val_t HAP_LOCK_CURRENT_STATE_SECURED = {.u = 1};
-static hap_val_t HAP_PROGRAMMABLE_SWITCH_EVENT_SINGLE_PRESS = {.u = 0};
-
-#define ESP_INTR_FLAG_DEFAULT 0
-
-static const uint8_t INTERCOM_EVENT_QUEUE_BELL = 1;
-static const uint8_t INTERCOM_EVENT_QUEUE_UNLOCK = 2;
-static const uint8_t INTERCOM_EVENT_QUEUE_LOCK = 3;
-static const uint8_t INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT = 4;
-
 /* static uint8_t tlv8buff[128];
 static hap_data_val_t null_tlv8 = {.buf = &tlv8buff, .buflen = 127}; */
 
-volatile uint32_t avg_bell_val = 0;
-volatile bool is_intercom_bell_blocked = false;
-static xQueueHandle intercom_event_queue = NULL;
-static TimerHandle_t intercom_lock_timer = NULL; // lock the door when timer triggered
-static TimerHandle_t intercom_bell_timer = NULL; // ignore new bells until timer triggered
-
-static bool is_bell_ringing(int val)
-{
-	return 1.2 < val && val < 2.5;
-}
-
-/**
- * @brief the recover intercom bell gpio interrupt function
- */
-static void IRAM_ATTR intercom_bell_isr(void *arg)
-{
-	if (!is_intercom_bell_blocked && is_bell_ringing(adc1_get_raw(CONFIG_HOMEKIT_INTERCOM_BELL_ADC1_CHANNEL)))
-	{
-		xQueueSendFromISR(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_BELL, NULL);
-		is_intercom_bell_blocked = true;
-	}
-}
-
-/**
- * Enable a GPIO Pin for Intercom Bell
- */
-static void intercom_bell_init(uint32_t key_gpio_pin)
-{
-	gpio_config_t io_conf;
-
-	io_conf.intr_type = GPIO_INTR_POSEDGE;		 /* Interrupt for rising edge  */
-	io_conf.pin_bit_mask = 1 << key_gpio_pin;	 /* Bit mask of the pins */
-	io_conf.mode = GPIO_MODE_INPUT;				 /* Set as input mode */
-	io_conf.pull_up_en = GPIO_PULLUP_DISABLE;	 /* Disable internal pull-up */
-	io_conf.pull_down_en = GPIO_PULLDOWN_ENABLE; /* Enable internal pull-down */
-
-	gpio_config(&io_conf); /* Set the GPIO configuration */
-
-	gpio_install_isr_service(ESP_INTR_FLAG_DEFAULT);							 /* Install gpio isr service */
-	gpio_isr_handler_add(key_gpio_pin, intercom_bell_isr, (void *)key_gpio_pin); /* Hook isr handler for specified gpio pin */
-
-	// https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/adc.html#_CPPv425adc1_config_channel_atten14adc1_channel_t11adc_atten_t
-	adc1_config_width(ADC_WIDTH_BIT_12);
-	adc1_config_channel_atten(CONFIG_HOMEKIT_INTERCOM_BELL_ADC1_CHANNEL, ADC_ATTEN_DB_11);
-}
-
-/**
- * Enable a GPIO Pin for Intercom Lock
- */
-static void intercom_lock_init(uint32_t key_gpio_pin)
-{
-	gpio_config_t io_conf;
-
-	io_conf.intr_type = GPIO_INTR_DISABLE;		 /* Disable interrupt  */
-	io_conf.pin_bit_mask = 1 << key_gpio_pin;	 /* Bit mask of the pins */
-	io_conf.mode = GPIO_MODE_OUTPUT;			 /* Set as input mode */
-	io_conf.pull_up_en = GPIO_PULLUP_DISABLE;	 /* Disable internal pull-up */
-	io_conf.pull_down_en = GPIO_PULLDOWN_ENABLE; /* Enable internal pull-down */
-
-	gpio_config(&io_conf); /* Set the GPIO configuration */
-}
-
-/**
- * Enable a GPIO Pin for LED
- */
 static void led_init(uint32_t key_gpio_pin)
 {
 	gpio_config_t io_conf;
@@ -123,28 +44,6 @@ static void led_init(uint32_t key_gpio_pin)
 	gpio_config(&io_conf); /* Set the GPIO configuration */
 }
 
-/**
- * Initialize the Intercom Hardware. Here, we just enebale the Intercom Bell detection.
- */
-void intercom_hardware_init(gpio_num_t reset_gpio_num, gpio_num_t intercom_bell_gpio_num, gpio_num_t intercom_lock_gpio_num, gpio_num_t led_gpio_num)
-{
-	int queue_len = 4;
-	int queue_item_size = sizeof(uint8_t);
-
-	intercom_event_queue = xQueueCreate(queue_len, queue_item_size);
-	if (intercom_event_queue != NULL)
-	{
-		/* reset_init(reset_gpio_num); */
-		intercom_bell_init(intercom_bell_gpio_num);
-		intercom_lock_init(intercom_lock_gpio_num);
-		led_init(led_gpio_num);
-	}
-}
-
-/* Mandatory identify routine for the accessory.
- * In a real accessory, something like LED blink should be implemented
- * got visual identification
- */
 static int intercom_identify(hap_acc_t *ha)
 {
 	ESP_LOGI(TAG, "Accessory identified");
@@ -160,89 +59,6 @@ static int intercom_identify(hap_acc_t *ha)
 	return HAP_SUCCESS;
 }
 
-static void intercom_bell_ring(hap_char_t *intercom_bell_current_state)
-{
-	ESP_LOGI(TAG, "Intercom bell ring event processed");
-
-	hap_char_update_val(intercom_bell_current_state, &HAP_PROGRAMMABLE_SWITCH_EVENT_SINGLE_PRESS);
-
-	xTimerReset(intercom_bell_timer, 10);
-}
-
-static void intercom_unlock(hap_char_t *intercom_lock_current_state)
-{
-	ESP_LOGI(TAG, "Intercom unlock event processed");
-
-	gpio_set_level(CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN, INTERCOM_LOCK_GPIO_UNLOCKED);
-	hap_char_update_val(intercom_lock_current_state, &HAP_LOCK_CURRENT_STATE_UNSECURED);
-
-	xTimerReset(intercom_lock_timer, 10);
-}
-
-static void intercom_lock(hap_char_t *intercom_lock_current_state)
-{
-	ESP_LOGI(TAG, "Intercom lock event processed");
-
-	gpio_set_level(CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN, INTERCOM_LOCK_GPIO_LOCKED);
-	hap_char_update_val(intercom_lock_current_state, &HAP_LOCK_CURRENT_STATE_SECURED);
-}
-
-static void intercom_lock_timeout(hap_char_t *intercom_lock_target_state)
-{
-	ESP_LOGI(TAG, "Intercom lock timeout event processed");
-
-	xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK, 10);
-	hap_val_t target_lock_secured = {.u = HAP_LOCK_TARGET_STATE_SECURED};
-	hap_char_update_val(intercom_lock_target_state, &target_lock_secured);
-}
-
-static void intercom_bell_timer_cb(TimerHandle_t timer)
-{
-	ESP_LOGI(TAG, "Intercom bell timer fired");
-	is_intercom_bell_blocked = false;
-}
-
-static int intercom_lock_write_cb(hap_write_data_t write_data[], int count, void *serv_priv, void *write_priv)
-{
-	int i, ret = HAP_SUCCESS;
-	hap_write_data_t *write;
-	for (i = 0; i < count; i++)
-	{
-		write = &write_data[i];
-		if (!strcmp(hap_char_get_type_uuid(write->hc), HAP_CHAR_UUID_LOCK_TARGET_STATE))
-		{
-			ESP_LOGI(TAG, "Received Write. Intercom lock %d", write->val.u);
-
-			switch (write->val.u)
-			{
-			case HAP_LOCK_TARGET_STATE_UNSECURED:
-				xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_UNLOCK, 10);
-				break;
-			case HAP_LOCK_TARGET_STATE_SECURED:
-				xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK, 10);
-				break;
-			}
-
-			/* Update target state */
-			hap_char_update_val(write->hc, &(write->val));
-			*(write->status) = HAP_STATUS_SUCCESS;
-		}
-		else
-		{
-			*(write->status) = HAP_STATUS_RES_ABSENT;
-		}
-	}
-	return ret;
-}
-
-static void intercom_lock_timer_cb(TimerHandle_t timer)
-{
-	ESP_LOGI(TAG, "Intercom lock timer fired - event queued");
-
-	xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT, 10);
-}
-
-/*The main thread for handling the Intercom Accessory */
 static void intercom_thread_entry(void *p)
 {
 	hap_init(HAP_TRANSPORT_WIFI); /* Initialize the HAP core */
@@ -268,26 +84,18 @@ static void intercom_thread_entry(void *p)
 	uint8_t product_data[] = {'E', 'S', 'P', '3', '2', 'H', 'A', 'P'};
 	hap_acc_add_product_data(intercom_accessory, product_data, sizeof(product_data));
 
-	hap_serv_t *intercom_bell_service = hap_serv_doorbell_create(0);
-	hap_serv_add_char(intercom_bell_service, hap_char_name_create("Intercom Bell"));
-	hap_char_t *intercom_bell_current_state = hap_serv_get_char_by_uuid(intercom_bell_service, HAP_CHAR_UUID_PROGRAMMABLE_SWITCH_EVENT);
-
-	hap_serv_t *intercom_lock_service = hap_serv_lock_mechanism_create(HAP_LOCK_CURRENT_STATE_SECURED.u, HAP_LOCK_TARGET_STATE_SECURED);
-	hap_serv_add_char(intercom_lock_service, hap_char_name_create("Intercom Lock"));
-	hap_char_t *intercom_lock_current_state = hap_serv_get_char_by_uuid(intercom_lock_service, HAP_CHAR_UUID_LOCK_CURRENT_STATE);
-	hap_char_t *intercom_lock_target_state = hap_serv_get_char_by_uuid(intercom_lock_service, HAP_CHAR_UUID_LOCK_TARGET_STATE);
-
-	/* Get pointer to the intercom in use characteristic which we need to monitor for state changes */
-	hap_serv_set_write_cb(intercom_lock_service, intercom_lock_write_cb); /* Set the write callback for the service */
+	if (!intercom_event_queue_init())
+	{
+		ESP_LOGI(TAG, "Failed to initialize event queue");
+		return;
+	}
 
-	hap_acc_add_serv(intercom_accessory, intercom_bell_service);
-	hap_acc_add_serv(intercom_accessory, intercom_lock_service);
+	hap_acc_add_serv(intercom_accessory, intercom_bell_init(CONFIG_HOMEKIT_INTERCOM_BELL_GPIO_PIN));
+	hap_acc_add_serv(intercom_accessory, intercom_lock_init(CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN));
+	led_init(CONFIG_HOMEKIT_INTERCOM_LED_GPIO_PIN);
 
 	hap_add_accessory(intercom_accessory); /* Add the Accessory to the HomeKit Database */
 
-	/* Initialize the appliance specific hardware. This enables out-in-use detection */
-	intercom_hardware_init(CONFIG_HOMEKIT_INTERCOM_WIFI_RESET_GPIO_PIN, CONFIG_HOMEKIT_INTERCOM_BELL_GPIO_PIN, CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN, CONFIG_HOMEKIT_INTERCOM_LED_GPIO_PIN);
-
 	/* For production accessories, the setup code shouldn't be programmed on to
 	 * the device. Instead, the setup info, derived from the setup code must
 	 * be used. Use the factory_nvs_gen utility to generate this data and then
@@ -317,40 +125,7 @@ static void intercom_thread_entry(void *p)
 	hap_start();				   /* After all the initializations are done, start the HAP core */
 	app_wifi_start(portMAX_DELAY); /* Start Wi-Fi */
 
-	intercom_lock_timer = xTimerCreate("intercom_lock_timer", pdMS_TO_TICKS(CONFIG_HOMEKIT_INTERCOM_LOCK_TIMEOUT), pdFALSE, 0, intercom_lock_timer_cb);
-	intercom_bell_timer = xTimerCreate("intercom_bell_timer", pdMS_TO_TICKS(CONFIG_HOMEKIT_INTERCOM_LOCK_TIMEOUT), pdFALSE, 0, intercom_bell_timer_cb);
-
-	/* Listen for intercom bell state change events. Other read/write functionality will be handled by the HAP Core.  When the
-	 * intercom bell in Use GPIO goes low, it means intercom bell is not ringing.  When the Intercom in Use GPIO goes high, it means
-	 * the intercom bell is ringing.  Applications can define own logic as per their hardware.
-	 */
-	uint8_t intercom_event_queue_item = INTERCOM_EVENT_QUEUE_LOCK;
-
-	while (1)
-	{
-		if (xQueueReceive(intercom_event_queue, &intercom_event_queue_item, portMAX_DELAY) == pdFALSE)
-		{
-			ESP_LOGI(TAG, "Intercom event queue trigger FAIL");
-		}
-		else
-		{
-			switch (intercom_event_queue_item)
-			{
-			case INTERCOM_EVENT_QUEUE_BELL:
-				intercom_bell_ring(intercom_bell_current_state);
-				break;
-			case INTERCOM_EVENT_QUEUE_UNLOCK:
-				intercom_unlock(intercom_lock_current_state);
-				break;
-			case INTERCOM_EVENT_QUEUE_LOCK:
-				intercom_lock(intercom_lock_current_state);
-				break;
-			case INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT:
-				intercom_lock_timeout(intercom_lock_target_state);
-				break;
-			}
-		}
-	}
+	intercom_event_queue_run();
 }
 
 void app_main()
diff --git a/main/include/bell.h b/main/include/bell.h
new file mode 100644
index 0000000..9dded29
--- /dev/null
+++ b/main/include/bell.h
@@ -0,0 +1,27 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+bool is_bell_ringing(int val);
+
+void IRAM_ATTR intercom_bell_isr(void *arg);
+
+void intercom_bell_ring();
+
+void intercom_bell_timer_cb(TimerHandle_t timer);
+
+hap_serv_t *intercom_bell_init(uint32_t key_gpio_pin);
diff --git a/main/include/event_queue.h b/main/include/event_queue.h
new file mode 100644
index 0000000..c101c36
--- /dev/null
+++ b/main/include/event_queue.h
@@ -0,0 +1,31 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+static const char *TAG = "HAP Intercom";
+
+void intercom_event_queue_bell_ring();
+
+void intercom_event_queue_lock_unsecure();
+
+void intercom_event_queue_lock_secure();
+
+void intercom_event_queue_lock_timeout();
+
+void intercom_event_queue_run();
+
+bool intercom_event_queue_init();
diff --git a/main/include/lock.h b/main/include/lock.h
new file mode 100644
index 0000000..983180c
--- /dev/null
+++ b/main/include/lock.h
@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+void intercom_lock_unsecure();
+
+void intercom_lock_secure();
+
+void intercom_lock_timeout();
+
+int intercom_lock_write_cb(hap_write_data_t write_data[], int count, void *serv_priv, void *write_priv);
+
+void intercom_lock_timer_cb(TimerHandle_t timer);
+
+hap_serv_t *intercom_lock_init(uint32_t key_gpio_pin);
diff --git a/main/src/bell.c b/main/src/bell.c
new file mode 100644
index 0000000..9467bb8
--- /dev/null
+++ b/main/src/bell.c
@@ -0,0 +1,86 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+#include <event_queue.h>
+#include <bell.h>
+
+#define ESP_INTR_FLAG_DEFAULT 0
+
+static hap_val_t HAP_PROGRAMMABLE_SWITCH_EVENT_SINGLE_PRESS = {.u = 0};
+
+volatile bool is_intercom_bell_blocked;
+static TimerHandle_t intercom_bell_timer; // ignore new bells until timer triggered
+static hap_char_t *intercom_bell_current_state;
+
+bool is_bell_ringing(int val)
+{
+    return 1.2 < val && val < 2.5;
+}
+
+void IRAM_ATTR intercom_bell_isr(void *arg)
+{
+    if (!is_intercom_bell_blocked && is_bell_ringing(adc1_get_raw(CONFIG_HOMEKIT_INTERCOM_BELL_ADC1_CHANNEL)))
+    {
+        intercom_event_queue_bell_ring();
+        is_intercom_bell_blocked = true;
+    }
+}
+
+void intercom_bell_ring()
+{
+    ESP_LOGI(TAG, "Intercom bell ring event processed");
+
+    hap_char_update_val(intercom_bell_current_state, &HAP_PROGRAMMABLE_SWITCH_EVENT_SINGLE_PRESS);
+
+    xTimerReset(intercom_bell_timer, 10);
+}
+
+void intercom_bell_timer_cb(TimerHandle_t timer)
+{
+    ESP_LOGI(TAG, "Intercom bell timer fired");
+    is_intercom_bell_blocked = false;
+}
+
+hap_serv_t *intercom_bell_init(uint32_t key_gpio_pin)
+{
+    is_intercom_bell_blocked = false;
+    intercom_bell_timer = xTimerCreate("intercom_bell_timer", pdMS_TO_TICKS(CONFIG_HOMEKIT_INTERCOM_LOCK_TIMEOUT), pdFALSE, 0, intercom_bell_timer_cb);
+
+    hap_serv_t *intercom_bell_service = hap_serv_doorbell_create(0);
+    hap_serv_add_char(intercom_bell_service, hap_char_name_create("Intercom Bell"));
+    intercom_bell_current_state = hap_serv_get_char_by_uuid(intercom_bell_service, HAP_CHAR_UUID_PROGRAMMABLE_SWITCH_EVENT);
+
+    gpio_config_t io_conf;
+
+    io_conf.intr_type = GPIO_INTR_POSEDGE;       /* Interrupt for rising edge  */
+    io_conf.pin_bit_mask = 1 << key_gpio_pin;    /* Bit mask of the pins */
+    io_conf.mode = GPIO_MODE_INPUT;              /* Set as input mode */
+    io_conf.pull_up_en = GPIO_PULLUP_DISABLE;    /* Disable internal pull-up */
+    io_conf.pull_down_en = GPIO_PULLDOWN_ENABLE; /* Enable internal pull-down */
+
+    gpio_config(&io_conf); /* Set the GPIO configuration */
+
+    gpio_install_isr_service(ESP_INTR_FLAG_DEFAULT);                             /* Install gpio isr service */
+    gpio_isr_handler_add(key_gpio_pin, intercom_bell_isr, (void *)key_gpio_pin); /* Hook isr handler for specified gpio pin */
+
+    // https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/adc.html#_CPPv425adc1_config_channel_atten14adc1_channel_t11adc_atten_t
+    adc1_config_width(ADC_WIDTH_BIT_12);
+    adc1_config_channel_atten(CONFIG_HOMEKIT_INTERCOM_BELL_ADC1_CHANNEL, ADC_ATTEN_DB_11);
+
+    return intercom_bell_service;
+}
diff --git a/main/src/event_queue.c b/main/src/event_queue.c
new file mode 100644
index 0000000..113cc56
--- /dev/null
+++ b/main/src/event_queue.c
@@ -0,0 +1,87 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+#include <lock.h>
+#include <bell.h>
+#include <event_queue.h>
+
+static const int INTERCOM_EVENT_QUEUE_BELL_RING = 1;
+static const int INTERCOM_EVENT_QUEUE_LOCK_UNSECURE = 2;
+static const int INTERCOM_EVENT_QUEUE_LOCK_SECURE = 3;
+static const int INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT = 4;
+
+static xQueueHandle intercom_event_queue = NULL;
+
+void intercom_event_queue_bell_ring()
+{
+    xQueueSendFromISR(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_BELL_RING, NULL);
+}
+
+void intercom_event_queue_lock_unsecure()
+{
+    xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK_UNSECURE, 10);
+}
+
+void intercom_event_queue_lock_secure()
+{
+    xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK_SECURE, 10);
+}
+
+void intercom_event_queue_lock_timeout()
+{
+    xQueueSendToBack(intercom_event_queue, (void *)&INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT, 10);
+}
+
+void intercom_event_queue_run()
+{
+    uint8_t intercom_event_queue_item = INTERCOM_EVENT_QUEUE_LOCK_SECURE;
+
+    while (1)
+    {
+        if (xQueueReceive(intercom_event_queue, &intercom_event_queue_item, portMAX_DELAY) == pdFALSE)
+        {
+            ESP_LOGI(TAG, "Intercom event queue trigger FAIL");
+        }
+        else
+        {
+            switch (intercom_event_queue_item)
+            {
+            case INTERCOM_EVENT_QUEUE_BELL_RING:
+                intercom_bell_ring();
+                break;
+            case INTERCOM_EVENT_QUEUE_LOCK_UNSECURE:
+                intercom_lock_unsecure();
+                break;
+            case INTERCOM_EVENT_QUEUE_LOCK_SECURE:
+                intercom_lock_secure();
+                break;
+            case INTERCOM_EVENT_QUEUE_LOCK_TIMEOUT:
+                intercom_lock_timeout();
+                break;
+            }
+        }
+    }
+}
+
+bool intercom_event_queue_init()
+{
+    int queue_len = 4;
+    int queue_item_size = sizeof(uint8_t);
+    intercom_event_queue = xQueueCreate(queue_len, queue_item_size);
+    return intercom_event_queue != NULL;
+}
diff --git a/main/src/lock.c b/main/src/lock.c
new file mode 100644
index 0000000..3d01383
--- /dev/null
+++ b/main/src/lock.c
@@ -0,0 +1,125 @@
+#include <stdio.h>
+#include <string.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/timers.h>
+#include <freertos/queue.h>
+#include <esp_log.h>
+#include <driver/gpio.h>
+#include <driver/adc.h>
+
+#include <hap.h>
+
+#include <hap_apple_servs.h>
+#include <hap_apple_chars.h>
+
+#include <app_wifi.h>
+#include <app_hap_setup_payload.h>
+
+#include <event_queue.h>
+#include <lock.h>
+
+#define INTERCOM_LOCK_GPIO_LOCKED 0
+#define INTERCOM_LOCK_GPIO_UNLOCKED 1
+
+#define HAP_LOCK_TARGET_STATE_UNSECURED 0
+#define HAP_LOCK_TARGET_STATE_SECURED 1
+
+static hap_val_t HAP_LOCK_CURRENT_STATE_UNSECURED = {.u = 0};
+static hap_val_t HAP_LOCK_CURRENT_STATE_SECURED = {.u = 1};
+
+static TimerHandle_t intercom_lock_timer = NULL; // lock the door when timer triggered
+static hap_char_t *intercom_lock_current_state;
+static hap_char_t *intercom_lock_target_state;
+
+void intercom_lock_unsecure()
+{
+    ESP_LOGI(TAG, "Intercom unlock event processed");
+
+    gpio_set_level(CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN, INTERCOM_LOCK_GPIO_UNLOCKED);
+    hap_char_update_val(intercom_lock_current_state, &HAP_LOCK_CURRENT_STATE_UNSECURED);
+
+    xTimerReset(intercom_lock_timer, 10);
+}
+
+void intercom_lock_secure()
+{
+    ESP_LOGI(TAG, "Intercom lock event processed");
+
+    gpio_set_level(CONFIG_HOMEKIT_INTERCOM_LOCK_GPIO_PIN, INTERCOM_LOCK_GPIO_LOCKED);
+    hap_char_update_val(intercom_lock_current_state, &HAP_LOCK_CURRENT_STATE_SECURED);
+}
+
+void intercom_lock_timeout()
+{
+    ESP_LOGI(TAG, "Intercom lock timeout event processed");
+
+    intercom_event_queue_lock_secure();
+    hap_val_t target_lock_secured = {.u = HAP_LOCK_TARGET_STATE_SECURED};
+    hap_char_update_val(intercom_lock_target_state, &target_lock_secured);
+}
+
+int intercom_lock_write_cb(hap_write_data_t write_data[], int count, void *serv_priv, void *write_priv)
+{
+    int i, ret = HAP_SUCCESS;
+    hap_write_data_t *write;
+    for (i = 0; i < count; i++)
+    {
+        write = &write_data[i];
+        if (!strcmp(hap_char_get_type_uuid(write->hc), HAP_CHAR_UUID_LOCK_TARGET_STATE))
+        {
+            ESP_LOGI(TAG, "Received Write. Intercom lock %d", write->val.u);
+
+            switch (write->val.u)
+            {
+            case HAP_LOCK_TARGET_STATE_UNSECURED:
+                intercom_event_queue_lock_unsecure();
+                break;
+            case HAP_LOCK_TARGET_STATE_SECURED:
+                intercom_event_queue_lock_secure();
+                break;
+            }
+
+            /* Update target state */
+            hap_char_update_val(write->hc, &(write->val));
+            *(write->status) = HAP_STATUS_SUCCESS;
+        }
+        else
+        {
+            *(write->status) = HAP_STATUS_RES_ABSENT;
+        }
+    }
+    return ret;
+}
+
+void intercom_lock_timer_cb(TimerHandle_t timer)
+{
+    ESP_LOGI(TAG, "Intercom lock timer fired - event queued");
+
+    intercom_event_queue_lock_timeout();
+}
+
+hap_serv_t *intercom_lock_init(uint32_t key_gpio_pin)
+{
+    hap_serv_t *intercom_lock_service = hap_serv_lock_mechanism_create(HAP_LOCK_CURRENT_STATE_SECURED.u, HAP_LOCK_TARGET_STATE_SECURED);
+    hap_serv_add_char(intercom_lock_service, hap_char_name_create("Intercom Lock"));
+
+    intercom_lock_current_state = hap_serv_get_char_by_uuid(intercom_lock_service, HAP_CHAR_UUID_LOCK_CURRENT_STATE);
+    intercom_lock_target_state = hap_serv_get_char_by_uuid(intercom_lock_service, HAP_CHAR_UUID_LOCK_TARGET_STATE);
+
+    hap_serv_set_write_cb(intercom_lock_service, intercom_lock_write_cb); /* Set the write callback for the service */
+
+    intercom_lock_timer = xTimerCreate("intercom_lock_timer", pdMS_TO_TICKS(CONFIG_HOMEKIT_INTERCOM_LOCK_TIMEOUT), pdFALSE, 0, intercom_lock_timer_cb);
+
+    gpio_config_t io_conf;
+
+    io_conf.intr_type = GPIO_INTR_DISABLE;       /* Disable interrupt  */
+    io_conf.pin_bit_mask = 1 << key_gpio_pin;    /* Bit mask of the pins */
+    io_conf.mode = GPIO_MODE_OUTPUT;             /* Set as input mode */
+    io_conf.pull_up_en = GPIO_PULLUP_DISABLE;    /* Disable internal pull-up */
+    io_conf.pull_down_en = GPIO_PULLDOWN_ENABLE; /* Enable internal pull-down */
+
+    gpio_config(&io_conf); /* Set the GPIO configuration */
+
+    return intercom_lock_service;
+}