update README

README.md

@@ -1,83 +1,41 @@
-# smart-oil-heating-control-system
+# Smart Oil Heating Control System
 
-## Software
-### Design
+ESP32-based control system for oil-fired central heating with schedule-based temperature management, safety monitoring, and Prometheus metrics export.
 
+## Features
+
+- **Schedule Control**: Day/night temperature targets per weekday
+- **Summer Mode**: Automatic heating disable based on outdoor temperature
+- **Safety Monitoring**: Sensor sanity checks with automatic safe-state fallback
+- **Prometheus Metrics**: HTTP endpoint at port 9100
+
+## System Overview
 ```mermaid
-classDiagram
-Inputs <|-- Control
-Outputs <|-- Control
-Sntp <|-- Control
-Inputs <|-- Safety
-Outputs <|--|> Safety
+flowchart TB
+    subgraph OUTSIDE[" "]
+        OT[/"🌡️ Outdoor Temp<br/>DS18B20"/]
+    end
 
-Inputs <|-- Metrics
-Outputs <|-- Metrics
-Control <|-- Metrics
-Safety <|-- Metrics
-Sntp <|-- Metrics
+    subgraph BURNER["OIL BURNER"]
+        CT[/"🌡️ Chamber Temp<br/>DS18B20"/]
+        BF[["⚠️ Burner Fault<br/>GPIO19 INPUT"]]
+        BR(["🔥 Burner Relay<br/>GPIO14"])
+        SC(["🔌 Safety Contact<br/>GPIO12"])
+    end
 
-    class Inputs{
-        +initInputs()
-        -initMeasurement()
-        -updateAverage()
-        -updatePrediction()
-        -taskInput()
-        -linearRegressionPredict()
-        +getChamberTemperature()
-        +getOutdoorTemperature()
-        +getInletFlowTemperature()
-        +getReturnFlowTemperature()
-        +getBurnerError()
-    }
+    subgraph CIRCUIT["HEATING CIRCUIT"]
+        IT[/"🌡️ Inlet Temp<br/>DS18B20"/]
+        CP(["💧 Circulation Pump<br/>GPIO27"])
+        RT[/"🌡️ Return Temp<br/>DS18B20"/]
+    end
 
-    class Outputs{
-        +initOutputs()
-        +getCirculationPumpState()
-        +setCirculationPumpState()
-        +getBurnerState()
-        +setBurnerState()
-        +getSafetyControlState()
-        +setSafetyControlState()
-    }
+    RAD["🏠 Radiators"]
 
-    class Control{
-        initControl()
-        +taskControl()
-        +getControlCurrentWeekday()
-        -findControlCurrentTemperatureEntry()
-        +getControlCurrentTemperatureEntry()
-        -controlTable
-        +getControlState()
-    }
-
-    class Safety{
-        +initSafety()
-        -taskSafety()
-        -setSafeState()
-        -checkSensorSanity()
-        +getSensorSanityStates()
-        +getSafetyState()
-    }
-
-
-    class Wifi{
-        +initWifi()
-    }
-
-    class Sntp{
-        +initSntp()
-        +getSntpState()
-    }
-
-    class Metrics{
-        +initMetrics()
-        -taskMetrics()
-        -metrics
-        +event_handler()
-        +connect_wifi()
-        +setMetrics()
-    }
+    BURNER -->|"hot water"| IT
+    IT --> CP
+    CP --> RAD
+    RAD --> RT
+    RT -->|"cold water"| BURNER
 ```
 
 ### Prometheus Metrics
@@ -88,26 +46,26 @@ burner_fault_pending 1
 circulation_pump_enabled 1
 burner_enabled 0
 safety_contact_enabled 1
-chamber_temperature 37.250000
-chamber_temperature_avg10 37.237499
-chamber_temperature_avg60 37.438541
-chamber_temperature_damped 42.185040
-chamber_temperature_pred60 36.638443
-inlet_flow_temperature 35.625000
-inlet_flow_temperature_avg10 35.618752
-inlet_flow_temperature_avg60 35.415627
-inlet_flow_temperature_damped 39.431259
-inlet_flow_temperature_pred60 36.078678
-outdoor_temperature 14.687500
-outdoor_temperature_avg10 14.662500
-outdoor_temperature_avg60 14.646875
-outdoor_temperature_damped 9.169084
-outdoor_temperature_pred60 14.660233
-return_flow_temperature 39.937500
-return_flow_temperature_avg10 40.087502
-return_flow_temperature_avg60 41.146873
-return_flow_temperature_damped 32.385151
-return_flow_temperature_pred60 37.311958
+chamber_temperature 37.312500
+chamber_temperature_avg10 37.393749
+chamber_temperature_avg60 37.689583
+chamber_temperature_damped 38.058098
+chamber_temperature_pred60 36.697266
+inlet_flow_temperature 34.562500
+inlet_flow_temperature_avg10 34.587502
+inlet_flow_temperature_avg60 34.880207
+inlet_flow_temperature_damped 35.255993
+inlet_flow_temperature_pred60 33.910374
+outdoor_temperature 1.812500
+outdoor_temperature_avg10 1.825000
+outdoor_temperature_avg60 1.821875
+outdoor_temperature_damped 2.390663
+outdoor_temperature_pred60 1.840263
+return_flow_temperature 34.125000
+return_flow_temperature_avg10 34.162498
+return_flow_temperature_avg60 34.304165
+return_flow_temperature_damped 31.430506
+return_flow_temperature_pred60 33.858772
 chamber_temperature_state 0
 outdoor_temperature_state 0
 inlet_flow_temperature_state 0
@@ -115,13 +73,13 @@ return_flow_temperature_state 0
 safety_state 0
 control_state 3
 control_current_weekday 5
-control_current_entry_time 17100
+control_current_entry_time 24300
 control_current_entry_chamber_temperature 80.000000
 control_current_entry_return_flow_temperature 30.000000
 sntp_state 0
-system_unixtime 1762012743
-uptime_seconds 465229
-wifi_rssi -72
+system_unixtime 1768067412
+uptime_seconds 344878
+wifi_rssi -59
 ```
 
 #### Status Encoding
@@ -180,4 +138,20 @@ wifi_rssi -72
 | Input Burner Fault                    | IO19  | Digital Input IN1 |
 | Input Temperature DS10B20             | IO04  | 1-Wire            |
 
+## Configuration
 
+All parameters configurable via `idf.py menuconfig`:
+- WiFi credentials and static IP
+- GPIO pin assignments
+- 1-Wire sensor addresses
+- Temperature thresholds and limits
+- Heating schedule (day/night per weekday)
+- Damping factors
+
+## Building
+
+```bash
+idf.py set-target esp32
+idf.py menuconfig  # Configure settings
+idf.py build flash monitor
+```

main/control.c

@@ -1,3 +1,8 @@
+/**
+ * @file control.c
+ * @brief Implementation of heating control module.
+ */
+
 #include "control.h"
 #include "inputs.h"
 #include "outputs.h"
@@ -9,11 +14,16 @@
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
 
-#define PERIODIC_INTERVAL 1U // Run control loop every 1 second
+#include <time.h>
+
+/** @brief Task interval in seconds. */
+#define PERIODIC_INTERVAL 1U
+
+static const char *TAG = "control";
 
-static const char *TAG = "smart-oil-heater-control-system-control";
 static eControlState gControlState = CONTROL_STARTING;
-// Control table for daily schedules
+
+/** @brief Weekly schedule table (from Kconfig). */
 static const sControlDay gControlTable[] = {
     {MONDAY,
      2U,
@@ -72,45 +82,49 @@ static const sControlDay gControlTable[] = {
        RETURN_FLOW_TEMPERATURE_LOWER_LIMIT_NIGHT,
        CHAMBER_TEMPERATURE_TARGET}}},
 };
+
 static sControlTemperatureEntry gCurrentControlEntry =
     gControlTable[0].aTemperatureEntries[0];
 static SemaphoreHandle_t xMutexAccessControl = NULL;
 
-// Function prototypes
-void taskControl(void *pvParameters);
-void findControlCurrentTemperatureEntry(void);
-void setControlState(eControlState state);
+/* Private function prototypes */
+static void taskControl(void *pvParameters);
+static void findControlCurrentTemperatureEntry(void);
+static void setControlState(eControlState state);
 
-void initControl(void)
+esp_err_t initControl(void)
 {
-
     xMutexAccessControl = xSemaphoreCreateRecursiveMutex();
     if (xMutexAccessControl == NULL)
     {
-        ESP_LOGE(TAG, "Unable to create mutex");
+        ESP_LOGE(TAG, "Failed to create mutex");
+        return ESP_FAIL;
     }
     xSemaphoreGiveRecursive(xMutexAccessControl);
 
-    BaseType_t taskCreated =
-        xTaskCreate(taskControl,   // Function to implement the task
-                    "taskControl", // Task name
-                    8192,          // Stack size (in words, not bytes)
-                    NULL,          // Parameters to the task function (none in this case)
-                    5,             // Task priority (higher number = higher priority)
-                    NULL           // Task handle (optional)
-        );
+    BaseType_t taskCreated = xTaskCreate(
+        taskControl,
+        "taskControl",
+        8192,
+        NULL,
+        5,
+        NULL);
 
-    if (taskCreated == pdPASS)
-    {
-        ESP_LOGI(TAG, "Task created successfully!");
-    }
-    else
+    if (taskCreated != pdPASS)
     {
         ESP_LOGE(TAG, "Failed to create task");
-    }
+        return ESP_FAIL;
     }
 
-void taskControl(void *pvParameters)
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
+}
+
+/**
+ * @brief Main control task.
+ * @param pvParameters Task parameters (unused).
+ */
+static void taskControl(void *pvParameters)
 {
     bool bHeatingInAction = false;
     bool bSummerMode = false;
@@ -121,7 +135,7 @@ void taskControl(void *pvParameters)
     {
         vTaskDelay(PERIODIC_INTERVAL * 1000U / portTICK_PERIOD_MS);
 
-        // Check for safety faults
+        /* Check for safety faults */
         if (getSafetyState() != SAFETY_NO_ERROR)
         {
             ESP_LOGW(TAG, "Control not possible due to safety fault!");
@@ -136,7 +150,7 @@ void taskControl(void *pvParameters)
             continue;
         }
 
-        // Check for SNTP faults
+        /* Check for SNTP faults */
         if (getSntpState() != SYNC_SUCCESSFUL)
         {
             ESP_LOGW(TAG, "Control not possible due to SNTP fault!");
@@ -153,35 +167,30 @@ void taskControl(void *pvParameters)
 
         findControlCurrentTemperatureEntry();
 
-        if (getOutdoorTemperature().fDampedValue >=
-            SUMMER_MODE_TEMPERATURE_THRESHOLD_HIGH)
+        /* Summer mode hysteresis */
+        if (getOutdoorTemperature().fDampedValue >= SUMMER_MODE_TEMPERATURE_THRESHOLD_HIGH)
         {
             bSummerMode = true;
         }
-        else if (getOutdoorTemperature().fDampedValue <=
-                 SUMMER_MODE_TEMPERATURE_THRESHOLD_LOW)
+        else if (getOutdoorTemperature().fDampedValue <= SUMMER_MODE_TEMPERATURE_THRESHOLD_LOW)
         {
             bSummerMode = false;
         }
 
-        // Enable burner if outdoor temperature is low and return flow temperature
-        // is cooled down
+        /* Enable burner if needed */
         if (!bHeatingInAction && (burnerState != BURNER_FAULT))
         {
             if (bSummerMode)
             {
-                // ESP_LOGI(TAG, "Outdoor temperature too warm: Disabling heating");
                 setBurnerState(DISABLED);
                 setSafetyControlState(DISABLED);
                 setControlState(CONTROL_OUTDOOR_TOO_WARM);
             }
             else if ((getReturnFlowTemperature().average60s.fValue <=
                       getControlCurrentTemperatureEntry().fReturnFlowTemperature) &&
-                     (getChamberTemperature().fCurrentValue <=
-                      CHAMBER_TEMPERATURE_THRESHOLD))
+                     (getChamberTemperature().fCurrentValue <= CHAMBER_TEMPERATURE_THRESHOLD))
             {
-                ESP_LOGI(TAG,
-                         "Enabling burner: Return flow temperature target reached");
+                ESP_LOGI(TAG, "Enabling burner: Return flow temperature target reached");
                 burnerState = BURNER_UNKNOWN;
                 bHeatingInAction = true;
                 setBurnerState(ENABLED);
@@ -191,12 +200,11 @@ void taskControl(void *pvParameters)
             }
             else
             {
-                // ESP_LOGI(TAG, "Return flow temperature too warm: Disabling heating");
                 setControlState(CONTROL_RETURN_FLOW_TOO_WARM);
             }
         }
 
-        // Disable burner if target temperature is reached or a fault occurred
+        /* Disable burner if target reached or fault */
         if (bHeatingInAction)
         {
             if ((getChamberTemperature().fCurrentValue >=
@@ -233,9 +241,8 @@ void taskControl(void *pvParameters)
             }
         }
 
-        // Manage circulation pump
-        if (getChamberTemperature().fCurrentValue <=
-            CIRCULATION_PUMP_TEMPERATURE_THRESHOLD)
+        /* Manage circulation pump */
+        if (getChamberTemperature().fCurrentValue <= CIRCULATION_PUMP_TEMPERATURE_THRESHOLD)
         {
             // ESP_LOGI(TAG, "Burner cooled down: Disabling circulation pump");
             setCirculationPumpState(DISABLED);
@@ -248,9 +255,12 @@ void taskControl(void *pvParameters)
     } // End of while(1)
 }
 
-void setControlState(eControlState state)
+/**
+ * @brief Set the control state with mutex protection.
+ * @param state New control state.
+ */
+static void setControlState(eControlState state)
 {
-
     if (xSemaphoreTakeRecursive(xMutexAccessControl, pdMS_TO_TICKS(5000)) == pdTRUE)
     {
         gControlState = state;
@@ -264,7 +274,6 @@ void setControlState(eControlState state)
 
 eControlState getControlState(void)
 {
-
     eControlState ret = CONTROL_FAULT_SAFETY;
 
     if (xSemaphoreTakeRecursive(xMutexAccessControl, pdMS_TO_TICKS(5000)) == pdTRUE)
@@ -282,7 +291,6 @@ eControlState getControlState(void)
 
 eControlWeekday getControlCurrentWeekday(void)
 {
-    // Get current time
     time_t now;
     struct tm timeinfo;
     time(&now);
@@ -293,24 +301,12 @@ eControlWeekday getControlCurrentWeekday(void)
 }
 
 /**
- * @brief Finds the active temperature control entry for the current time.
- *
- * Searches through the weekly schedule to find the most recent entry
- * that should be active at the current date/time. Falls back to the
- * last entry in the week if no suitable entry is found.
+ * @brief Find the currently active temperature entry based on time.
  */
-/**
- * @brief Finds the active temperature control entry for the current time.
- *
- * Searches through the weekly schedule to find the most recent entry
- * that should be active at the current date/time. Falls back to the
- * last entry in the week if no suitable entry is found.
- */
-void findControlCurrentTemperatureEntry(void)
+static void findControlCurrentTemperatureEntry(void)
 {
     eControlWeekday currentDay = getControlCurrentWeekday();
 
-    // Get current time
     time_t now;
     struct tm timeinfo;
     time(&now);
@@ -361,6 +357,7 @@ void findControlCurrentTemperatureEntry(void)
                         const sControlDay *sunday = &gControlTable[6];
                         gCurrentControlEntry = sunday->aTemperatureEntries[sunday->entryCount - 1];
                     }
+                    xSemaphoreGiveRecursive(xMutexAccessControl);
                     /*
                     ESP_LOGI(TAG, "Active entry found - Time: %02d:%02d, "
                     "Return Temp: %lf, Chamber Temp: %lf",

main/control.h

@@ -1,38 +1,74 @@
+/**
+ * @file control.h
+ * @brief Heating control logic with schedule-based temperature management.
+ *
+ * This module implements the main heating control loop. It manages
+ * burner operation based on time schedules, temperature targets,
+ * and summer mode detection.
+ */
+
 #pragma once
 
 #include "sdkconfig.h"
+#include "esp_err.h"
 
-#include <time.h>
+#include <stdint.h>
+#include <stddef.h>
 
+/** @brief Maximum number of temperature entries per day. */
 #define MAX_TEMPERATURE_ENTRIES_PER_DAY 24U
 
+/** @brief Return flow target temperature for day mode (°C). */
 #define RETURN_FLOW_TEMPERATURE_LOWER_LIMIT_DAY (CONFIG_TEMP_RETURN_FLOW_LOWER_LIMIT_DAY / 10.0f)
+
+/** @brief Return flow target temperature for night mode (°C). */
 #define RETURN_FLOW_TEMPERATURE_LOWER_LIMIT_NIGHT (CONFIG_TEMP_RETURN_FLOW_LOWER_LIMIT_NIGHT / 10.0f)
+
+/** @brief Chamber target temperature (°C). */
 #define CHAMBER_TEMPERATURE_TARGET (CONFIG_TEMP_CHAMBER_TARGET / 10.0f)
+
+/** @brief Chamber temperature threshold to enable burner (°C). */
 #define CHAMBER_TEMPERATURE_THRESHOLD (CONFIG_TEMP_CHAMBER_THRESHOLD / 10.0f)
+
+/** @brief Outdoor temperature to activate summer mode (°C). */
 #define SUMMER_MODE_TEMPERATURE_THRESHOLD_HIGH (CONFIG_TEMP_SUMMER_MODE_HIGH / 10.0f)
+
+/** @brief Outdoor temperature to deactivate summer mode (°C). */
 #define SUMMER_MODE_TEMPERATURE_THRESHOLD_LOW (CONFIG_TEMP_SUMMER_MODE_LOW / 10.0f)
+
+/** @brief Chamber temperature threshold for circulation pump (°C). */
 #define CIRCULATION_PUMP_TEMPERATURE_THRESHOLD (CONFIG_TEMP_CIRCULATION_PUMP_THRESHOLD / 10.0f)
+
+/** @brief Time to wait before checking burner fault (seconds). */
 #define BURNER_FAULT_DETECTION_THRESHOLD CONFIG_BURNER_FAULT_DETECTION_SECONDS
 
+/**
+ * @brief Control state enumeration.
+ */
 typedef enum _ControlState
 {
-    CONTROL_STARTING,
-    CONTROL_HEATING,
-    CONTROL_OUTDOOR_TOO_WARM,
-    CONTROL_RETURN_FLOW_TOO_WARM,
-    CONTROL_FAULT_BURNER,
-    CONTROL_FAULT_SAFETY,
-    CONTROL_FAULT_SNTP,
+    CONTROL_STARTING,             /**< System starting up. */
+    CONTROL_HEATING,              /**< Burner running. */
+    CONTROL_OUTDOOR_TOO_WARM,     /**< Summer mode active. */
+    CONTROL_RETURN_FLOW_TOO_WARM, /**< Target temperature reached. */
+    CONTROL_FAULT_BURNER,         /**< Burner fault detected. */
+    CONTROL_FAULT_SAFETY,         /**< Safety fault detected. */
+    CONTROL_FAULT_SNTP,           /**< SNTP sync failed. */
 } eControlState;
 
+/**
+ * @brief Burner operational state enumeration.
+ */
 typedef enum _BurnerState
 {
-    BURNER_UNKNOWN, // Burner is disabled or state after enabling is still unkown
-    BURNER_FIRED,   // Burner fired successfully
-    BURNER_FAULT    // Burner was unable to fire successfully
+    BURNER_UNKNOWN, /**< Burner state unknown after enable. */
+    BURNER_FIRED,   /**< Burner fired successfully. */
+    BURNER_FAULT    /**< Burner failed to fire. */
 } eBurnerState;
 
+/**
+ * @brief Weekday enumeration (Monday = 0).
+ */
 typedef enum _ControlWeekday
 {
     MONDAY,
@@ -44,27 +80,58 @@ typedef enum _ControlWeekday
     SUNDAY,
 } eControlWeekday;
 
+/**
+ * @brief Time of day structure.
+ */
 typedef struct _ControlTimestamp
 {
-    uint8_t hour;
-    uint8_t minute;
+    uint8_t hour;   /**< Hour (0-23). */
+    uint8_t minute; /**< Minute (0-59). */
 } sControlTimestamp;
 
+/**
+ * @brief Temperature schedule entry.
+ */
 typedef struct _ControlTemperatureEntry
 {
-    sControlTimestamp timestamp;
-    float fReturnFlowTemperature;
-    float fChamberTemperature;
+    sControlTimestamp timestamp;  /**< Time when entry becomes active. */
+    float fReturnFlowTemperature; /**< Target return flow temperature. */
+    float fChamberTemperature;    /**< Target chamber temperature. */
 } sControlTemperatureEntry;
 
+/**
+ * @brief Daily schedule structure.
+ */
 typedef struct _ControlDay
 {
-    eControlWeekday day;
-    size_t entryCount; // number of entries for each day
-    sControlTemperatureEntry aTemperatureEntries[MAX_TEMPERATURE_ENTRIES_PER_DAY];
+    eControlWeekday day;                                                           /**< Day of week. */
+    size_t entryCount;                                                             /**< Number of entries for this day. */
+    sControlTemperatureEntry aTemperatureEntries[MAX_TEMPERATURE_ENTRIES_PER_DAY]; /**< Schedule entries. */
 } sControlDay;
 
-void initControl(void);
+/**
+ * @brief Initialize the control module.
+ *
+ * Creates the control task that manages heating operation.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initControl(void);
+
+/**
+ * @brief Get the current control state.
+ * @return eControlState indicating current operation mode.
+ */
 eControlState getControlState(void);
+
+/**
+ * @brief Get the current weekday.
+ * @return eControlWeekday (Monday = 0, Sunday = 6).
+ */
 eControlWeekday getControlCurrentWeekday(void);
+
+/**
+ * @brief Get the currently active temperature entry.
+ * @return sControlTemperatureEntry with current targets.
+ */
 sControlTemperatureEntry getControlCurrentTemperatureEntry(void);

main/inputs.c

@@ -1,3 +1,8 @@
+/**
+ * @file inputs.c
+ * @brief Implementation of input handling module.
+ */
+
 #include "inputs.h"
 
 #include "freertos/FreeRTOS.h"
@@ -9,22 +14,38 @@
 #include <string.h>
 #include <math.h>
 
+/** @brief Maximum number of DS18B20 sensors supported. */
 #define MAX_DN18B20_SENSORS 4U
-#define ONE_WIRE_LOOPS 4U    // try to read the 1-Wire sensors that often
-#define PERIODIC_INTERVAL 1U // read and compute the inputs every 1sec
 
-static const char *TAG = "smart-oil-heater-control-system-inputs";
-const uint8_t uBurnerFaultPin = CONFIG_GPIO_BURNER_FAULT;
-const uint8_t uDS18B20Pin = CONFIG_GPIO_DS18B20_ONEWIRE;
+/** @brief Number of retry attempts for 1-Wire read. */
+#define ONE_WIRE_LOOPS 4U
 
-const onewire_addr_t uChamperTempSensorAddr = CONFIG_ONEWIRE_ADDR_CHAMBER_TEMP;
-const onewire_addr_t uOutdoorTempSensorAddr = CONFIG_ONEWIRE_ADDR_OUTDOOR_TEMP;
-const onewire_addr_t uInletFlowTempSensorAddr = CONFIG_ONEWIRE_ADDR_INLET_FLOW_TEMP;
-const onewire_addr_t uReturnFlowTempSensorAddr = CONFIG_ONEWIRE_ADDR_RETURN_FLOW_TEMP;
+/** @brief Task interval in seconds. */
+#define PERIODIC_INTERVAL 1U
 
-onewire_addr_t uOneWireAddresses[MAX_DN18B20_SENSORS];
-float fDS18B20Temps[MAX_DN18B20_SENSORS];
-size_t sSensorCount = 0U;
+static const char *TAG = "inputs";
+
+/** @brief Burner fault GPIO pin (from Kconfig). */
+static const uint8_t uBurnerFaultPin = CONFIG_GPIO_BURNER_FAULT;
+
+/** @brief DS18B20 1-Wire GPIO pin (from Kconfig). */
+static const uint8_t uDS18B20Pin = CONFIG_GPIO_DS18B20_ONEWIRE;
+
+/** @brief Chamber temperature sensor address (from Kconfig). */
+static const onewire_addr_t uChamperTempSensorAddr = CONFIG_ONEWIRE_ADDR_CHAMBER_TEMP;
+
+/** @brief Outdoor temperature sensor address (from Kconfig). */
+static const onewire_addr_t uOutdoorTempSensorAddr = CONFIG_ONEWIRE_ADDR_OUTDOOR_TEMP;
+
+/** @brief Inlet flow temperature sensor address (from Kconfig). */
+static const onewire_addr_t uInletFlowTempSensorAddr = CONFIG_ONEWIRE_ADDR_INLET_FLOW_TEMP;
+
+/** @brief Return flow temperature sensor address (from Kconfig). */
+static const onewire_addr_t uReturnFlowTempSensorAddr = CONFIG_ONEWIRE_ADDR_RETURN_FLOW_TEMP;
+
+static onewire_addr_t uOneWireAddresses[MAX_DN18B20_SENSORS];
+static float fDS18B20Temps[MAX_DN18B20_SENSORS];
+static size_t sSensorCount = 0U;
 
 static SemaphoreHandle_t xMutexAccessInputs = NULL;
 static eBurnerErrorState sBurnerErrorState;
@@ -33,34 +54,34 @@ static sMeasurement sOutdoorTemperature;
 static sMeasurement sInletFlowTemperature;
 static sMeasurement sReturnFlowTemperature;
 
-void taskInput(void *pvParameters);
-void initMeasurement(sMeasurement *pMeasurement);
-void updateAverage(sMeasurement *pMeasurement);
-void updatePrediction(sMeasurement *pMeasurement);
-float linearRegressionPredict(const float *samples, size_t count, size_t bufferIndex, float futureIndex);
+/* Private function prototypes */
+static void taskInput(void *pvParameters);
+static void initMeasurement(sMeasurement *pMeasurement);
+static void updateAverage(sMeasurement *pMeasurement);
+static void updatePrediction(sMeasurement *pMeasurement);
+static float linearRegressionPredict(const float *samples, size_t count, size_t bufferIndex, float futureIndex);
 
-void initInputs(void)
+esp_err_t initInputs(void)
 {
-
     gpio_config_t ioConfBurnerFault = {
-        .pin_bit_mask = (1ULL << uBurnerFaultPin), // Pin mask
-        .mode = GPIO_MODE_INPUT,                   // Set as inout
-        .pull_up_en = GPIO_PULLUP_ENABLE,          // Enable pull-up
-        .pull_down_en = GPIO_PULLDOWN_DISABLE,     // Disable pull-down
-        .intr_type = GPIO_INTR_DISABLE             // Disable interrupts
-    };
+        .pin_bit_mask = (1ULL << uBurnerFaultPin),
+        .mode = GPIO_MODE_INPUT,
+        .pull_up_en = GPIO_PULLUP_ENABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE};
 
     esp_err_t ret = gpio_config(&ioConfBurnerFault);
     if (ret != ESP_OK)
     {
         ESP_LOGE(TAG, "GPIO config failed: %s", esp_err_to_name(ret));
-        return;
+        return ESP_FAIL;
     }
 
     xMutexAccessInputs = xSemaphoreCreateRecursiveMutex();
     if (xMutexAccessInputs == NULL)
     {
-        ESP_LOGE(TAG, "Unable to create mutex");
+        ESP_LOGE(TAG, "Failed to create mutex");
+        return ESP_FAIL;
     }
     xSemaphoreGiveRecursive(xMutexAccessInputs);
 
@@ -70,25 +91,28 @@ void initInputs(void)
     initMeasurement(&sReturnFlowTemperature);
 
     BaseType_t taskCreated = xTaskCreate(
-        taskInput,   // Function to implement the task
-        "taskInput", // Task name
-        4096,        // Stack size (in words, not bytes)
-        NULL,        // Parameters to the task function (none in this case)
-        5,           // Task priority (higher number = higher priority)
-        NULL         // Task handle (optional)
-    );
+        taskInput,
+        "taskInput",
+        4096,
+        NULL,
+        5,
+        NULL);
 
-    if (taskCreated == pdPASS)
-    {
-        ESP_LOGI(TAG, "Task created successfully!");
-    }
-    else
+    if (taskCreated != pdPASS)
     {
         ESP_LOGE(TAG, "Failed to create task");
-    }
+        return ESP_FAIL;
     }
 
-void initMeasurement(sMeasurement *pMeasurement)
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
+}
+
+/**
+ * @brief Initialize a measurement structure to default values.
+ * @param pMeasurement Pointer to measurement structure.
+ */
+static void initMeasurement(sMeasurement *pMeasurement)
 {
     if (!pMeasurement)
         return;
@@ -113,12 +137,16 @@ void initMeasurement(sMeasurement *pMeasurement)
     memset(pMeasurement->predict60s.samples, 0U, sizeof(float) * PRED60S_SAMPLE_SIZE);
 }
 
-void updateAverage(sMeasurement *pMeasurement)
+/**
+ * @brief Update average values and damped value for a measurement.
+ * @param pMeasurement Pointer to measurement structure.
+ */
+static void updateAverage(sMeasurement *pMeasurement)
 {
     if (!pMeasurement)
         return;
 
-    // Average form the last 10sec
+    /* 10-second average */
     pMeasurement->average10s.samples[pMeasurement->average10s.bufferIndex] = pMeasurement->fCurrentValue;
     pMeasurement->average10s.bufferIndex = (pMeasurement->average10s.bufferIndex + 1) % AVG10S_SAMPLE_SIZE;
 
@@ -142,7 +170,7 @@ void updateAverage(sMeasurement *pMeasurement)
         pMeasurement->average10s.fValue = sum / pMeasurement->average10s.bufferCount;
     }
 
-    // Average form the last 60sec
+    /* 60-second average */
     pMeasurement->average60s.samples[pMeasurement->average60s.bufferIndex] = pMeasurement->fCurrentValue;
     pMeasurement->average60s.bufferIndex = (pMeasurement->average60s.bufferIndex + 1) % AVG60S_SAMPLE_SIZE;
 
@@ -166,7 +194,7 @@ void updateAverage(sMeasurement *pMeasurement)
         pMeasurement->average60s.fValue = sum / pMeasurement->average60s.bufferCount;
     }
 
-    // Damped current value
+    /* Damped current value */
     if (pMeasurement->fDampedValue == INITIALISATION_VALUE)
     {
         pMeasurement->fDampedValue = pMeasurement->fCurrentValue;
@@ -185,7 +213,11 @@ void updateAverage(sMeasurement *pMeasurement)
     }
 }
 
-void updatePrediction(sMeasurement *pMeasurement)
+/**
+ * @brief Update 60-second prediction using linear regression.
+ * @param pMeasurement Pointer to measurement structure.
+ */
+static void updatePrediction(sMeasurement *pMeasurement)
 {
     if (!pMeasurement)
         return;
@@ -205,7 +237,11 @@ void updatePrediction(sMeasurement *pMeasurement)
         predict60s->bufferCount + 60.0f);
 }
 
-void taskInput(void *pvParameters)
+/**
+ * @brief Input task - reads sensors periodically.
+ * @param pvParameters Task parameters (unused).
+ */
+static void taskInput(void *pvParameters)
 {
     while (1)
     {
@@ -307,20 +343,27 @@ void taskInput(void *pvParameters)
     }
 }
 
-float linearRegressionPredict(const float *samples, size_t count, size_t bufferIndex, float futureIndex)
+/**
+ * @brief Predict future value using linear regression.
+ * @param samples Sample buffer.
+ * @param count Number of valid samples.
+ * @param bufferIndex Current buffer write index.
+ * @param futureIndex Future time index to predict.
+ * @return Predicted value.
+ */
+static float linearRegressionPredict(const float *samples, size_t count, size_t bufferIndex, float futureIndex)
 {
     if (count == 0)
-        return INITIALISATION_VALUE; // No prediction possible with no data
+        return INITIALISATION_VALUE;
 
     float sumX = INITIALISATION_VALUE, sumY = INITIALISATION_VALUE, sumXY = INITIALISATION_VALUE, sumX2 = INITIALISATION_VALUE;
 
     for (size_t i = 0; i < count; i++)
     {
-        // Calculate the circular buffer index for the current sample
         size_t circularIndex = (bufferIndex + i + 1) % count;
 
-        float x = (float)i;               // Time index
-        float y = samples[circularIndex]; // Sample value
+        float x = (float)i;
+        float y = samples[circularIndex];
 
         sumX += x;
         sumY += y;
@@ -328,15 +371,13 @@ float linearRegressionPredict(const float *samples, size_t count, size_t bufferI
         sumX2 += x * x;
     }
 
-    // Calculate slope (m) and intercept (b) of the line: y = mx + b
     float denominator = (count * sumX2 - sumX * sumX);
-    if (fabs(denominator) < 1e-6)    // Avoid division by zero
-        return samples[bufferIndex]; // Return the latest value as prediction
+    if (fabs(denominator) < 1e-6)
+        return samples[bufferIndex];
 
     float m = (count * sumXY - sumX * sumY) / denominator;
     float b = (sumY - m * sumX) / count;
 
-    // Predict value at futureIndex
     return m * futureIndex + b;
 }
 

main/inputs.h

@@ -1,59 +1,133 @@
+/**
+ * @file inputs.h
+ * @brief Input handling for temperature sensors and burner fault detection.
+ *
+ * This module reads DS18B20 temperature sensors via 1-Wire and monitors
+ * the burner fault input. It provides averaged, damped, and predicted
+ * temperature values.
+ */
+
 #pragma once
 
 #include "sdkconfig.h"
 
+#include "esp_err.h"
+
 #include <stddef.h>
 
+/** @brief Returns the maximum of two values. */
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
+
+/** @brief Initial value for measurements before first reading. */
 #define INITIALISATION_VALUE 0.0f
+
+/** @brief Sample buffer size for 10-second average. */
 #define AVG10S_SAMPLE_SIZE 10U
+
+/** @brief Sample buffer size for 60-second average. */
 #define AVG60S_SAMPLE_SIZE 60U
+
+/** @brief Sample buffer size for 24-hour average. */
 #define AVG24H_SAMPLE_SIZE 24U
+
+/** @brief Sample buffer size for 60-second prediction. */
 #define PRED60S_SAMPLE_SIZE 60U
+
+/** @brief Damping factor for rising temperatures (from Kconfig). */
 #define DAMPING_FACTOR_WARMER (CONFIG_DAMPING_FACTOR_WARMER * 0.00001f)
+
+/** @brief Damping factor for falling temperatures (from Kconfig). */
 #define DAMPING_FACTOR_COLDER (CONFIG_DAMPING_FACTOR_COLDER * 0.00001f)
 
+/**
+ * @brief Burner error state enumeration.
+ */
 typedef enum _BurnerErrorState
 {
-    NO_ERROR,
-    FAULT
+    NO_ERROR, /**< No burner fault detected. */
+    FAULT     /**< Burner fault signal active. */
 } eBurnerErrorState;
 
+/**
+ * @brief Measurement error state enumeration.
+ */
 typedef enum _MeasurementErrorState
 {
-    MEASUREMENT_NO_ERROR,
-    MEASUREMENT_FAULT
+    MEASUREMENT_NO_ERROR, /**< Measurement valid. */
+    MEASUREMENT_FAULT     /**< Measurement failed or sensor not found. */
 } eMeasurementErrorState;
 
+/**
+ * @brief Circular buffer for averaging temperature values.
+ */
 typedef struct _Average
 {
-    float fValue;
-    float samples[MAX(AVG10S_SAMPLE_SIZE, MAX(AVG60S_SAMPLE_SIZE, AVG24H_SAMPLE_SIZE))];
-    size_t bufferIndex;
-    size_t bufferCount;
+    float fValue;                                                                        /**< Current average value. */
+    float samples[MAX(AVG10S_SAMPLE_SIZE, MAX(AVG60S_SAMPLE_SIZE, AVG24H_SAMPLE_SIZE))]; /**< Sample buffer. */
+    size_t bufferIndex;                                                                  /**< Current write index. */
+    size_t bufferCount;                                                                  /**< Number of valid samples. */
 } sAverage;
 
+/**
+ * @brief Circular buffer for temperature prediction.
+ */
 typedef struct _Predict
 {
-    float fValue;
-    float samples[PRED60S_SAMPLE_SIZE];
-    size_t bufferIndex;
-    size_t bufferCount;
+    float fValue;                       /**< Predicted value. */
+    float samples[PRED60S_SAMPLE_SIZE]; /**< Sample buffer. */
+    size_t bufferIndex;                 /**< Current write index. */
+    size_t bufferCount;                 /**< Number of valid samples. */
 } sPredict;
 
+/**
+ * @brief Complete measurement data structure.
+ */
 typedef struct _Measurement
 {
-    float fCurrentValue;
-    float fDampedValue;
-    sAverage average10s;
-    sAverage average60s;
-    sPredict predict60s;
-    eMeasurementErrorState state;
+    float fCurrentValue;          /**< Current raw temperature value. */
+    float fDampedValue;           /**< Damped temperature value. */
+    sAverage average10s;          /**< 10-second rolling average. */
+    sAverage average60s;          /**< 60-second rolling average. */
+    sPredict predict60s;          /**< 60-second prediction. */
+    eMeasurementErrorState state; /**< Measurement state. */
 } sMeasurement;
 
-void initInputs(void);
+/**
+ * @brief Initialize the inputs module.
+ *
+ * Configures GPIO for burner fault input and starts the input task
+ * for reading DS18B20 temperature sensors.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initInputs(void);
+
+/**
+ * @brief Get the current chamber temperature measurement.
+ * @return sMeasurement structure with current values and state.
+ */
 sMeasurement getChamberTemperature(void);
+
+/**
+ * @brief Get the current outdoor temperature measurement.
+ * @return sMeasurement structure with current values and state.
+ */
 sMeasurement getOutdoorTemperature(void);
+
+/**
+ * @brief Get the current inlet flow temperature measurement.
+ * @return sMeasurement structure with current values and state.
+ */
 sMeasurement getInletFlowTemperature(void);
+
+/**
+ * @brief Get the current return flow temperature measurement.
+ * @return sMeasurement structure with current values and state.
+ */
 sMeasurement getReturnFlowTemperature(void);
+
+/**
+ * @brief Get the current burner error state.
+ * @return eBurnerErrorState indicating fault status.
+ */
 eBurnerErrorState getBurnerError(void);

main/main.c

@@ -1,3 +1,11 @@
+/**
+ * @file main.c
+ * @brief Main entry point for Smart Oil Heating Control System.
+ *
+ * This file initializes all system modules and handles initialization
+ * errors by logging diagnostic information and triggering a reboot.
+ */
+
 #include "safety.h"
 #include "metrics.h"
 #include "outputs.h"
@@ -9,30 +17,107 @@
 #include "esp_log.h"
 #include "esp_system.h"
 #include "nvs_flash.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
-static const char *TAG = "smart-oil-heater-control-system";
+static const char *TAG = "main";
 
+/** @brief Delay before reboot in milliseconds. */
+#define REBOOT_DELAY_MS 5000
+
+/**
+ * @brief Log error and trigger system reboot.
+ * @param module Name of the module that failed.
+ */
+static void reboot_on_error(const char *module)
+{
+    ESP_LOGE(TAG, "========================================");
+    ESP_LOGE(TAG, "FATAL: %s initialization failed!", module);
+    ESP_LOGE(TAG, "System will reboot in %d seconds...", REBOOT_DELAY_MS / 1000);
+    ESP_LOGE(TAG, "========================================");
+
+    vTaskDelay(pdMS_TO_TICKS(REBOOT_DELAY_MS));
+    esp_restart();
+}
+
+/**
+ * @brief Application main entry point.
+ */
 void app_main(void)
 {
-    ESP_LOGI(TAG, "starting ...");
+    ESP_LOGI(TAG, "========================================");
+    ESP_LOGI(TAG, "Smart Oil Heating Control System");
+    ESP_LOGI(TAG, "Starting initialization...");
+    ESP_LOGI(TAG, "========================================");
 
-    // Initialize NVS
+    /* Initialize NVS */
     esp_err_t ret = nvs_flash_init();
     if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND)
     {
+        ESP_LOGW(TAG, "NVS partition needs erase, erasing...");
         ESP_ERROR_CHECK(nvs_flash_erase());
         ret = nvs_flash_init();
     }
-    ESP_ERROR_CHECK(ret);
+    if (ret != ESP_OK)
+    {
+        ESP_LOGE(TAG, "NVS init failed: %s", esp_err_to_name(ret));
+        reboot_on_error("NVS");
+    }
+    ESP_LOGI(TAG, "[OK] NVS initialized");
 
-    // TODO: Error handling!
-    initOutputs();
-    initInputs();
-    initSafety();
-    initWifi();
-    initSntp();
-    initControl();
-    initMetrics();
+    /* Initialize Outputs */
+    if (initOutputs() != ESP_OK)
+    {
+        reboot_on_error("Outputs");
+    }
+    ESP_LOGI(TAG, "[OK] Outputs initialized");
+
+    /* Initialize Inputs */
+    if (initInputs() != ESP_OK)
+    {
+        reboot_on_error("Inputs");
+    }
+    ESP_LOGI(TAG, "[OK] Inputs initialized");
+
+    /* Initialize Safety */
+    if (initSafety() != ESP_OK)
+    {
+        reboot_on_error("Safety");
+    }
+    ESP_LOGI(TAG, "[OK] Safety initialized");
+
+    /* Initialize WiFi */
+    if (initWifi() != ESP_OK)
+    {
+        reboot_on_error("WiFi");
+    }
+    ESP_LOGI(TAG, "[OK] WiFi initialized");
+
+    /* Initialize SNTP */
+    if (initSntp() != ESP_OK)
+    {
+        reboot_on_error("SNTP");
+    }
+    ESP_LOGI(TAG, "[OK] SNTP initialized");
+
+    /* Initialize Control */
+    if (initControl() != ESP_OK)
+    {
+        reboot_on_error("Control");
+    }
+    ESP_LOGI(TAG, "[OK] Control initialized");
+
+    /* Initialize Metrics */
+    if (initMetrics() != ESP_OK)
+    {
+        reboot_on_error("Metrics");
+    }
+    ESP_LOGI(TAG, "[OK] Metrics initialized");
+
+    ESP_LOGI(TAG, "========================================");
+    ESP_LOGI(TAG, "All modules initialized successfully!");
+    ESP_LOGI(TAG, "System is now running.");
+    ESP_LOGI(TAG, "========================================");
 
     while (1)
     {

main/metrics.c

@@ -1,3 +1,8 @@
+/**
+ * @file metrics.c
+ * @brief Implementation of Prometheus metrics endpoint.
+ */
+
 #include "metrics.h"
 #include "outputs.h"
 #include "inputs.h"
@@ -15,41 +20,50 @@
 #include <time.h>
 #include <sys/time.h>
 
-static const char *TAG = "smart-oil-heater-control-system-metrics";
+static const char *TAG = "metrics";
 
-char caHtmlResponse[HTML_RESPONSE_SIZE];
-SemaphoreHandle_t xMutexAccessMetricResponse = NULL;
+static char caHtmlResponse[HTML_RESPONSE_SIZE];
+static SemaphoreHandle_t xMutexAccessMetricResponse = NULL;
 static sMetric aMetrics[METRIC_MAX_COUNT];
 static uint16_t u16MetricCounter = 0U;
 
-void taskMetrics(void *pvParameters);
-httpd_handle_t setup_server(void);
-esp_err_t get_metrics_handler(httpd_req_t *req);
+/* Private function prototypes */
+static void taskMetrics(void *pvParameters);
+static httpd_handle_t setup_server(void);
+static esp_err_t get_metrics_handler(httpd_req_t *req);
 
-void initMetrics(void)
+esp_err_t initMetrics(void)
 {
-    setup_server();
+    httpd_handle_t server = setup_server();
+    if (server == NULL)
+    {
+        ESP_LOGE(TAG, "Failed to start HTTP server");
+        return ESP_FAIL;
+    }
 
     BaseType_t taskCreated = xTaskCreate(
-        taskMetrics,   // Function to implement the task
-        "taskMetrics", // Task name
-        32768,         // Stack size (in words, not bytes)
-        NULL,          // Parameters to the task function (none in this case)
-        5,             // Task priority (higher number = higher priority)
-        NULL           // Task handle (optional)
-    );
+        taskMetrics,
+        "taskMetrics",
+        32768,
+        NULL,
+        5,
+        NULL);
 
-    if (taskCreated == pdPASS)
-    {
-        ESP_LOGI(TAG, "Task created successfully!");
-    }
-    else
+    if (taskCreated != pdPASS)
     {
         ESP_LOGE(TAG, "Failed to create task");
-    }
+        return ESP_FAIL;
     }
 
-void taskMetrics(void *pvParameters)
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
+}
+
+/**
+ * @brief Metrics collection task.
+ * @param pvParameters Task parameters (unused).
+ */
+static void taskMetrics(void *pvParameters)
 {
     while (1)
     {
@@ -338,8 +352,6 @@ void vSetMetrics(sMetric *paMetrics, uint16_t u16Size)
                 break;
             }
 
-            // printf("%s\n", paMetrics[u16Index].caMetricName);
-            // printf("%s\n", caValueBuffer);
             strcat(caHtmlResponse, paMetrics[u16Index].caMetricName);
             strcat(caHtmlResponse, caValueBuffer);
             strcat(caHtmlResponse, "\n");
@@ -352,7 +364,12 @@ void vSetMetrics(sMetric *paMetrics, uint16_t u16Size)
     }
 }
 
-esp_err_t get_metrics_handler(httpd_req_t *req)
+/**
+ * @brief HTTP GET handler for /metrics endpoint.
+ * @param req HTTP request.
+ * @return ESP_OK on success.
+ */
+static esp_err_t get_metrics_handler(httpd_req_t *req)
 {
     if (xSemaphoreTakeRecursive(xMutexAccessMetricResponse, pdMS_TO_TICKS(5000)) == pdTRUE)
     {
@@ -367,7 +384,11 @@ esp_err_t get_metrics_handler(httpd_req_t *req)
     }
 }
 
-httpd_handle_t setup_server(void)
+/**
+ * @brief Setup HTTP server for metrics endpoint.
+ * @return HTTP server handle or NULL on failure.
+ */
+static httpd_handle_t setup_server(void)
 {
     httpd_config_t config = HTTPD_DEFAULT_CONFIG();
     config.server_port = 9100;
@@ -382,14 +403,17 @@ httpd_handle_t setup_server(void)
     xMutexAccessMetricResponse = xSemaphoreCreateRecursiveMutex();
     if (xMutexAccessMetricResponse == NULL)
     {
-        ESP_LOGE(TAG, "Unable to create mutex for metric response");
+        ESP_LOGE(TAG, "Failed to create mutex");
+        return NULL;
     }
     xSemaphoreGiveRecursive(xMutexAccessMetricResponse);
 
     if (httpd_start(&server, &config) == ESP_OK)
     {
         httpd_register_uri_handler(server, &uri_get);
-    }
-
         return server;
     }
+
+    ESP_LOGE(TAG, "Failed to start HTTP server");
+    return NULL;
+}

main/metrics.h

@@ -1,26 +1,61 @@
+/**
+ * @file metrics.h
+ * @brief Prometheus metrics HTTP endpoint.
+ *
+ * This module provides a HTTP server on port 9100 that exposes
+ * system metrics in Prometheus format at /metrics endpoint.
+ */
+
 #pragma once
 
-#include <esp_http_server.h>
+#include "esp_err.h"
+#include "esp_http_server.h"
 
+#include <stdint.h>
+
+/** @brief Maximum size of HTTP response buffer. */
 #define HTML_RESPONSE_SIZE 4096U
+
+/** @brief Maximum length of metric name. */
 #define METRIC_NAME_MAX_SIZE 64U
+
+/** @brief Maximum number of metrics. */
 #define METRIC_MAX_COUNT 38U
 
+/**
+ * @brief Metric value type enumeration.
+ */
 typedef enum _MetricValueType
 {
-    FLOAT,
-    INTEGER_U8,
-    INTEGER_64,
+    FLOAT,      /**< Floating point value. */
+    INTEGER_U8, /**< 8-bit unsigned integer. */
+    INTEGER_64, /**< 64-bit signed integer. */
 } eMetricValueType;
 
+/**
+ * @brief Metric data structure.
+ */
 typedef struct _metric
 {
-    char caMetricName[METRIC_NAME_MAX_SIZE];
-    eMetricValueType type;
-    float fMetricValue;
-    uint8_t u8MetricValue;
-    int64_t i64MetricValue;
+    char caMetricName[METRIC_NAME_MAX_SIZE]; /**< Metric name. */
+    eMetricValueType type;                   /**< Value type. */
+    float fMetricValue;                      /**< Float value (if type is FLOAT). */
+    uint8_t u8MetricValue;                   /**< U8 value (if type is INTEGER_U8). */
+    int64_t i64MetricValue;                  /**< I64 value (if type is INTEGER_64). */
 } sMetric;
 
-void initMetrics(void);
+/**
+ * @brief Initialize the metrics module.
+ *
+ * Starts the HTTP server and creates the metrics collection task.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initMetrics(void);
+
+/**
+ * @brief Update the metrics buffer.
+ * @param paMetrics Array of metrics to publish.
+ * @param u16Size Number of metrics in array.
+ */
 void vSetMetrics(sMetric *paMetrics, uint16_t u16Size);

main/outputs.c

@@ -1,3 +1,8 @@
+/**
+ * @file outputs.c
+ * @brief Implementation of output control module.
+ */
+
 #include "outputs.h"
 
 #include "sdkconfig.h"
@@ -6,69 +11,76 @@
 #include "driver/gpio.h"
 #include "esp_log.h"
 
-static const char *TAG = "smart-oil-heater-control-system-outputs";
-const uint8_t uCirculationPumpGpioPin = CONFIG_GPIO_CIRCULATION_PUMP;
-const uint8_t uBurnerGpioPin = CONFIG_GPIO_BURNER;
-const uint8_t uSafetyContactGpioPin = CONFIG_GPIO_SAFETY_CONTACT;
+static const char *TAG = "outputs";
+
+/** @brief Circulation pump GPIO pin (from Kconfig). */
+static const uint8_t uCirculationPumpGpioPin = CONFIG_GPIO_CIRCULATION_PUMP;
+
+/** @brief Burner control GPIO pin (from Kconfig). */
+static const uint8_t uBurnerGpioPin = CONFIG_GPIO_BURNER;
+
+/** @brief Safety contact GPIO pin (from Kconfig). */
+static const uint8_t uSafetyContactGpioPin = CONFIG_GPIO_SAFETY_CONTACT;
 
 static SemaphoreHandle_t xMutexAccessOutputs = NULL;
 static eOutput sCirculationPumpState;
 static eOutput sBurnerState;
 static eOutput sSafetyContactState;
 
-void initOutputs(void)
+esp_err_t initOutputs(void)
 {
     gpio_config_t ioConfCirculationPump = {
-        .pin_bit_mask = (1ULL << uCirculationPumpGpioPin), // Pin mask
-        .mode = GPIO_MODE_OUTPUT,                          // Set as output
-        .pull_up_en = GPIO_PULLUP_DISABLE,                 // Disable pull-up
-        .pull_down_en = GPIO_PULLDOWN_DISABLE,             // Disable pull-down
-        .intr_type = GPIO_INTR_DISABLE                     // Disable interrupts
-    };
+        .pin_bit_mask = (1ULL << uCirculationPumpGpioPin),
+        .mode = GPIO_MODE_OUTPUT,
+        .pull_up_en = GPIO_PULLUP_DISABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE};
 
     gpio_config_t ioConfBurner = {
-        .pin_bit_mask = (1ULL << uBurnerGpioPin), // Pin mask
-        .mode = GPIO_MODE_OUTPUT,                 // Set as output
-        .pull_up_en = GPIO_PULLUP_DISABLE,        // Disable pull-up
-        .pull_down_en = GPIO_PULLDOWN_DISABLE,    // Disable pull-down
-        .intr_type = GPIO_INTR_DISABLE            // Disable interrupts
-    };
+        .pin_bit_mask = (1ULL << uBurnerGpioPin),
+        .mode = GPIO_MODE_OUTPUT,
+        .pull_up_en = GPIO_PULLUP_DISABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE};
 
     gpio_config_t ioConfSafetyContact = {
-        .pin_bit_mask = (1ULL << uSafetyContactGpioPin), // Pin mask
-        .mode = GPIO_MODE_OUTPUT,                        // Set as output
-        .pull_up_en = GPIO_PULLUP_DISABLE,               // Disable pull-up
-        .pull_down_en = GPIO_PULLDOWN_DISABLE,           // Disable pull-down
-        .intr_type = GPIO_INTR_DISABLE                   // Disable interrupts
-    };
+        .pin_bit_mask = (1ULL << uSafetyContactGpioPin),
+        .mode = GPIO_MODE_OUTPUT,
+        .pull_up_en = GPIO_PULLUP_DISABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE};
 
     esp_err_t ret = gpio_config(&ioConfCirculationPump);
     if (ret != ESP_OK)
     {
-        ESP_LOGE(TAG, "GPIO config failed: %s", esp_err_to_name(ret));
-        return;
+        ESP_LOGE(TAG, "GPIO config failed for circulation pump: %s", esp_err_to_name(ret));
+        return ESP_FAIL;
     }
 
     ret = gpio_config(&ioConfBurner);
     if (ret != ESP_OK)
     {
-        ESP_LOGE(TAG, "GPIO config failed: %s", esp_err_to_name(ret));
-        return;
+        ESP_LOGE(TAG, "GPIO config failed for burner: %s", esp_err_to_name(ret));
+        return ESP_FAIL;
     }
 
     ret = gpio_config(&ioConfSafetyContact);
     if (ret != ESP_OK)
     {
-        ESP_LOGE(TAG, "GPIO config failed: %s", esp_err_to_name(ret));
-        return;
+        ESP_LOGE(TAG, "GPIO config failed for safety contact: %s", esp_err_to_name(ret));
+        return ESP_FAIL;
     }
 
     xMutexAccessOutputs = xSemaphoreCreateRecursiveMutex();
     if (xMutexAccessOutputs == NULL)
     {
-        ESP_LOGE(TAG, "Unable to create mutex");
+        ESP_LOGE(TAG, "Failed to create mutex");
+        return ESP_FAIL;
     }
     xSemaphoreGiveRecursive(xMutexAccessOutputs);
+
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
 }
 
 eOutput getCirculationPumpState(void)

main/outputs.h

@@ -1,15 +1,70 @@
+/**
+ * @file outputs.h
+ * @brief Output control for circulation pump, burner, and safety contact.
+ *
+ * This module controls the relay outputs via GPIO pins. All outputs
+ * are active-low (relay energized when GPIO is low).
+ */
+
 #pragma once
 
+#include "esp_err.h"
+
+/**
+ * @brief Output state enumeration.
+ */
 typedef enum _Output
 {
-    ENABLED,
-    DISABLED
+    ENABLED, /**< Output active (relay energized, GPIO low). */
+    DISABLED /**< Output inactive (relay de-energized, GPIO high). */
 } eOutput;
 
-void initOutputs(void);
+/**
+ * @brief Initialize the outputs module.
+ *
+ * Configures GPIO pins for circulation pump, burner, and safety contact
+ * as outputs. All outputs are initialized to DISABLED (safe state).
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initOutputs(void);
+
+/**
+ * @brief Get the current circulation pump state.
+ * @return eOutput state (ENABLED or DISABLED).
+ */
 eOutput getCirculationPumpState(void);
+
+/**
+ * @brief Set the circulation pump state.
+ * @param in Desired state (ENABLED or DISABLED).
+ */
 void setCirculationPumpState(eOutput in);
+
+/**
+ * @brief Get the current burner state.
+ * @return eOutput state (ENABLED or DISABLED).
+ */
 eOutput getBurnerState(void);
+
+/**
+ * @brief Set the burner state.
+ * @param in Desired state (ENABLED or DISABLED).
+ */
 void setBurnerState(eOutput in);
+
+/**
+ * @brief Get the current safety contact state.
+ * @return eOutput state (ENABLED or DISABLED).
+ */
 eOutput getSafetyControlState(void);
+
+/**
+ * @brief Set the safety contact state.
+ *
+ * The safety contact controls power to the burner. When DISABLED,
+ * the burner cannot operate regardless of the burner signal.
+ *
+ * @param in Desired state (ENABLED or DISABLED).
+ */
 void setSafetyControlState(eOutput in);

main/safety.c

@@ -1,3 +1,8 @@
+/**
+ * @file safety.c
+ * @brief Implementation of safety monitoring module.
+ */
+
 #include "safety.h"
 
 #include "freertos/FreeRTOS.h"
@@ -7,53 +12,68 @@
 #include <string.h>
 #include <math.h>
 
-#define PERIODIC_INTERVAL 1U                                           // run safety checks every 1sec
-#define SENSOR_GRACE_PERIOD (CONFIG_SENSOR_GRACE_PERIOD_MINUTES * 60U) // period that a sensor can report the same reading in seconds
+/** @brief Task interval in seconds. */
+#define PERIODIC_INTERVAL 1U
+
+/** @brief Grace period for unchanged sensor readings (seconds). */
+#define SENSOR_GRACE_PERIOD (CONFIG_SENSOR_GRACE_PERIOD_MINUTES * 60U)
+
+/** @brief Epsilon for float comparison. */
 #define FLOAT_EPSILON 0.0001f
-static const char *TAG = "smart-oil-heater-control-system-safety";
+
+static const char *TAG = "safety";
+
 static SemaphoreHandle_t xMutexAccessSafety = NULL;
+
+/** @brief Sensor sanity check configurations. */
 static sSensorSanityCheck sanityChecks[NUMBER_OF_SENSOR_SANITY_CHECKS] = {
     {SENSOR_NO_ERROR, "chamber_temperature", {SENSOR_LIMIT_CHAMBER_MAX, SENSOR_LIMIT_CHAMBER_MIN}, 0.0f, 0U, getChamberTemperature},
     {SENSOR_NO_ERROR, "outdoor_temperature", {SENSOR_LIMIT_OUTDOOR_MAX, SENSOR_LIMIT_OUTDOOR_MIN}, 0.0f, 0U, getOutdoorTemperature},
     {SENSOR_NO_ERROR, "inlet_flow_temperature", {SENSOR_LIMIT_INLET_MAX, SENSOR_LIMIT_INLET_MIN}, 0.0f, 0U, getInletFlowTemperature},
     {SENSOR_NO_ERROR, "return_flow_temperature", {SENSOR_LIMIT_RETURN_MAX, SENSOR_LIMIT_RETURN_MIN}, 0.0f, 0U, getReturnFlowTemperature}};
+
 static eSafetyState sSafetyState = SAFETY_NO_ERROR;
 
-void taskSafety(void *pvParameters);
-void checkSensorSanity(void);
-void setSafeState(void);
+/* Private function prototypes */
+static void taskSafety(void *pvParameters);
+static void checkSensorSanity(void);
+static void setSafeState(void);
 
-void initSafety(void)
+esp_err_t initSafety(void)
 {
     xMutexAccessSafety = xSemaphoreCreateRecursiveMutex();
     if (xMutexAccessSafety == NULL)
     {
-        ESP_LOGE(TAG, "Unable to create mutex");
+        ESP_LOGE(TAG, "Failed to create mutex");
+        return ESP_FAIL;
     }
     xSemaphoreGiveRecursive(xMutexAccessSafety);
 
     BaseType_t taskCreated = xTaskCreate(
-        taskSafety,   // Function to implement the task
-        "taskSafety", // Task name
-        4096,         // Stack size (in words, not bytes)
-        NULL,         // Parameters to the task function (none in this case)
-        5,            // Task priority (higher number = higher priority)
-        NULL          // Task handle (optional)
-    );
+        taskSafety,
+        "taskSafety",
+        4096,
+        NULL,
+        5,
+        NULL);
 
-    if (taskCreated == pdPASS)
-    {
-        ESP_LOGI(TAG, "Task created successfully!");
-    }
-    else
+    if (taskCreated != pdPASS)
     {
         ESP_LOGE(TAG, "Failed to create task");
+        return ESP_FAIL;
     }
 
-    setSafeState(); // Set inital state
+    setSafeState();
+
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
 }
 
-void taskSafety(void *pvParameters)
+/**
+ * @brief Safety monitoring task.
+ * @param pvParameters Task parameters (unused).
+ */
+static void taskSafety(void *pvParameters)
 {
     while (1)
     {
@@ -61,7 +81,6 @@ void taskSafety(void *pvParameters)
 
         if (xSemaphoreTakeRecursive(xMutexAccessSafety, portMAX_DELAY) == pdTRUE)
         {
-
             checkSensorSanity();
 
             if (sSafetyState != SAFETY_NO_ERROR)
@@ -74,7 +93,10 @@ void taskSafety(void *pvParameters)
     }
 }
 
-void checkSensorSanity(void)
+/**
+ * @brief Check all sensor readings for sanity.
+ */
+static void checkSensorSanity(void)
 {
     sSafetyState = SAFETY_NO_ERROR;
     for (int i = 0; i < NUMBER_OF_SENSOR_SANITY_CHECKS; i++)
@@ -130,7 +152,10 @@ void checkSensorSanity(void)
     }
 }
 
-void setSafeState(void)
+/**
+ * @brief Set system to safe state (burner off, pump on).
+ */
+static void setSafeState(void)
 {
     setCirculationPumpState(ENABLED); // To cool down system
     setBurnerState(DISABLED);         // Deactivate burner

main/safety.h

@@ -1,56 +1,117 @@
+/**
+ * @file safety.h
+ * @brief Safety monitoring for temperature sensors.
+ *
+ * This module performs sanity checks on all temperature sensors and
+ * puts the system into a safe state if any sensor fails.
+ */
+
 #pragma once
 
 #include "outputs.h"
 #include "inputs.h"
 
 #include "sdkconfig.h"
+#include "esp_err.h"
 
 #include <stdint.h>
 
+/** @brief Maximum length of sensor name string. */
 #define MAX_ERROR_STRING_SIZE 64U
+
+/** @brief Number of sensors to monitor. */
 #define NUMBER_OF_SENSOR_SANITY_CHECKS 4U
 
+/** @brief Chamber sensor maximum temperature limit (°C). */
 #define SENSOR_LIMIT_CHAMBER_MAX (CONFIG_SENSOR_LIMIT_CHAMBER_MAX / 10.0f)
+
+/** @brief Chamber sensor minimum temperature limit (°C). */
 #define SENSOR_LIMIT_CHAMBER_MIN (CONFIG_SENSOR_LIMIT_CHAMBER_MIN / 10.0f)
+
+/** @brief Outdoor sensor maximum temperature limit (°C). */
 #define SENSOR_LIMIT_OUTDOOR_MAX (CONFIG_SENSOR_LIMIT_OUTDOOR_MAX / 10.0f)
+
+/** @brief Outdoor sensor minimum temperature limit (°C). */
 #define SENSOR_LIMIT_OUTDOOR_MIN (CONFIG_SENSOR_LIMIT_OUTDOOR_MIN / 10.0f)
+
+/** @brief Inlet flow sensor maximum temperature limit (°C). */
 #define SENSOR_LIMIT_INLET_MAX (CONFIG_SENSOR_LIMIT_INLET_MAX / 10.0f)
+
+/** @brief Inlet flow sensor minimum temperature limit (°C). */
 #define SENSOR_LIMIT_INLET_MIN (CONFIG_SENSOR_LIMIT_INLET_MIN / 10.0f)
+
+/** @brief Return flow sensor maximum temperature limit (°C). */
 #define SENSOR_LIMIT_RETURN_MAX (CONFIG_SENSOR_LIMIT_RETURN_MAX / 10.0f)
+
+/** @brief Return flow sensor minimum temperature limit (°C). */
 #define SENSOR_LIMIT_RETURN_MIN (CONFIG_SENSOR_LIMIT_RETURN_MIN / 10.0f)
 
+/**
+ * @brief Sensor error state enumeration.
+ */
 typedef enum _SensorErrorState
 {
-    SENSOR_NO_ERROR,
-    SENSOR_TOO_HIGH,
-    SENSOR_TOO_LOW,
-    SENSOR_UNCHANGED,
-    SENSOR_NOT_FOUND
+    SENSOR_NO_ERROR,  /**< Sensor operating normally. */
+    SENSOR_TOO_HIGH,  /**< Temperature above maximum limit. */
+    SENSOR_TOO_LOW,   /**< Temperature below minimum limit. */
+    SENSOR_UNCHANGED, /**< Temperature unchanged for too long. */
+    SENSOR_NOT_FOUND  /**< Sensor not responding. */
 } eSensorErrorState;
 
+/**
+ * @brief Overall safety state enumeration.
+ */
 typedef enum _SafetyState
 {
-    SAFETY_NO_ERROR,
-    SAFETY_SENSOR_ERROR,
-    SAFETY_INTERNAL_ERROR
+    SAFETY_NO_ERROR,      /**< All sensors OK. */
+    SAFETY_SENSOR_ERROR,  /**< At least one sensor failed. */
+    SAFETY_INTERNAL_ERROR /**< Internal module error. */
 } eSafetyState;
 
+/**
+ * @brief Function pointer type for sensor getter functions.
+ */
 typedef sMeasurement (*GetSensorValue)();
+
+/**
+ * @brief Temperature sensor limits.
+ */
 typedef struct _TemperatureSensorLimit
 {
-    float max; // Maximum temperature limit
-    float min; // Minimum temperature limit
+    float max; /**< Maximum temperature limit. */
+    float min; /**< Minimum temperature limit. */
 } sTemperatureSensorLimit;
+
+/**
+ * @brief Sensor sanity check state structure.
+ */
 typedef struct _SensorSanityCheck
 {
-    eSensorErrorState state;
-    char name[MAX_ERROR_STRING_SIZE];
-    sTemperatureSensorLimit sSensorLimit;
-    float fSensorTemperatureLast;
-    uint32_t uUnchangedCounter;
-    GetSensorValue getSensor;
+    eSensorErrorState state;              /**< Current error state. */
+    char name[MAX_ERROR_STRING_SIZE];     /**< Sensor name for logging. */
+    sTemperatureSensorLimit sSensorLimit; /**< Temperature limits. */
+    float fSensorTemperatureLast;         /**< Last temperature reading. */
+    uint32_t uUnchangedCounter;           /**< Counter for unchanged readings. */
+    GetSensorValue getSensor;             /**< Function to get sensor value. */
 } sSensorSanityCheck;
 
-void initSafety(void);
+/**
+ * @brief Initialize the safety module.
+ *
+ * Creates the safety monitoring task and sets initial safe state.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initSafety(void);
+
+/**
+ * @brief Get the current sensor sanity states.
+ * @param[out] pSensorSanityChecks Array to receive sensor states.
+ */
 void getSensorSanityStates(sSensorSanityCheck *pSensorSanityChecks);
+
+/**
+ * @brief Get the overall safety state.
+ * @return eSafetyState indicating current safety status.
+ */
 eSafetyState getSafetyState(void);

main/sntp.c

@@ -1,3 +1,8 @@
+/**
+ * @file sntp.c
+ * @brief Implementation of SNTP client module.
+ */
+
 #include "sntp.h"
 
 #include "esp_sntp.h"
@@ -6,17 +11,22 @@
 #include <time.h>
 #include <sys/time.h>
 
-static const char *TAG = "smart-oil-heater-control-system-sntp";
-static volatile eSntpState sntpState = SYNC_NOT_STARTED;
-void time_sync_notification_cb(struct timeval *tv);
+static const char *TAG = "sntp";
 
-void initSntp(void)
+static volatile eSntpState sntpState = SYNC_NOT_STARTED;
+
+static void time_sync_notification_cb(struct timeval *tv);
+
+esp_err_t initSntp(void)
 {
     esp_sntp_setoperatingmode(SNTP_OPMODE_POLL);
     esp_sntp_setservername(0, CONFIG_SNTP_SERVER_IP_ADDR);
 
     sntp_set_time_sync_notification_cb(time_sync_notification_cb);
     esp_sntp_init();
+
+    ESP_LOGI(TAG, "Initialized successfully, server: %s", CONFIG_SNTP_SERVER_IP_ADDR);
+    return ESP_OK;
 }
 
 eSntpState getSntpState(void)
@@ -24,8 +34,12 @@ eSntpState getSntpState(void)
     return sntpState;
 }
 
-void time_sync_notification_cb(struct timeval *tv)
+/**
+ * @brief SNTP time sync callback.
+ * @param tv Synchronized time value.
+ */
+static void time_sync_notification_cb(struct timeval *tv)
 {
-    ESP_LOGI(TAG, "SNTP synchronization! Unix Time: %lld", tv->tv_sec);
+    ESP_LOGI(TAG, "Time synchronized! Unix Time: %lld", tv->tv_sec);
     sntpState = SYNC_SUCCESSFUL;
 }

main/sntp.h

@@ -1,11 +1,37 @@
+/**
+ * @file sntp.h
+ * @brief SNTP client for time synchronization.
+ *
+ * This module synchronizes system time with an NTP server.
+ * Time sync is required for schedule-based heating control.
+ */
+
 #pragma once
 
+#include "esp_err.h"
+
+/**
+ * @brief SNTP synchronization state enumeration.
+ */
 typedef enum _SntpState
 {
-    SYNC_SUCCESSFUL,
-    SYNC_NOT_STARTED,
-    SYNC_FAILED,
+    SYNC_SUCCESSFUL,  /**< Time synchronized successfully. */
+    SYNC_NOT_STARTED, /**< Synchronization not yet attempted. */
+    SYNC_FAILED,      /**< Synchronization failed. */
 } eSntpState;
 
-void initSntp(void);
+/**
+ * @brief Initialize the SNTP client.
+ *
+ * Configures SNTP with the server from Kconfig and starts
+ * periodic time synchronization.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initSntp(void);
+
+/**
+ * @brief Get the current SNTP synchronization state.
+ * @return eSntpState indicating sync status.
+ */
 eSntpState getSntpState(void);

main/wifi.c

@@ -1,3 +1,8 @@
+/**
+ * @file wifi.c
+ * @brief Implementation of WiFi station mode module.
+ */
+
 #include "wifi.h"
 
 #include "esp_timer.h"
@@ -12,12 +17,19 @@
 
 #include <string.h>
 
+/** @brief Event bit for successful connection. */
 #define WIFI_CONNECTED_BIT BIT0
+
+/** @brief Event bit for connection failure. */
 #define WIFI_FAIL_BIT BIT1
+
+/** @brief Maximum connection retry attempts. */
 #define MAX_RETRY_COUNT 10
+
+/** @brief Delay between retries in milliseconds. */
 #define RETRY_DELAY_MS 1000
 
-static const char *TAG = "smart-oil-heater-control-system-wifi";
+static const char *TAG = "wifi";
 
 static EventGroupHandle_t s_wifi_event_group;
 static int s_retry_num = 0;
@@ -26,13 +38,13 @@ static bool s_initial_connect = true;
 static void event_handler(void *arg, esp_event_base_t event_base,
                           int32_t event_id, void *event_data);
 
-void initWifi(void)
+esp_err_t initWifi(void)
 {
     s_wifi_event_group = xEventGroupCreate();
     if (s_wifi_event_group == NULL)
     {
-        ESP_LOGE(TAG, "xEventGroupCreate() failed!");
-        return;
+        ESP_LOGE(TAG, "Failed to create event group");
+        return ESP_FAIL;
     }
 
     ESP_ERROR_CHECK(esp_netif_init());
@@ -73,10 +85,10 @@ void initWifi(void)
 
     ESP_ERROR_CHECK(esp_wifi_start());
 
-    ESP_ERROR_CHECK(esp_wifi_set_max_tx_power(78));      // Set max power to 19.5 dBm (78 in units of 0.25 dBm)
-    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_MIN_MODEM)); // Use power-saving mode
+    ESP_ERROR_CHECK(esp_wifi_set_max_tx_power(78));
+    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_MIN_MODEM));
 
-    ESP_LOGI(TAG, "wifi_init_sta finished.");
+    ESP_LOGI(TAG, "WiFi init finished, waiting for connection...");
 
     EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
                                            WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
@@ -86,21 +98,32 @@ void initWifi(void)
 
     if (bits & WIFI_CONNECTED_BIT)
     {
-        ESP_LOGI(TAG, "Connected to ap SSID:%s", CONFIG_SSID);
+        ESP_LOGI(TAG, "Connected to AP SSID:%s", CONFIG_SSID);
     }
     else if (bits & WIFI_FAIL_BIT)
     {
-        ESP_LOGI(TAG, "Failed to connect to SSID:%s", CONFIG_SSID);
+        ESP_LOGE(TAG, "Failed to connect to SSID:%s", CONFIG_SSID);
+        return ESP_FAIL;
     }
     else
     {
         ESP_LOGE(TAG, "Unexpected event");
+        return ESP_FAIL;
     }
 
-    // Mark initial connection phase complete - do NOT delete the event group
     s_initial_connect = false;
+
+    ESP_LOGI(TAG, "Initialized successfully");
+    return ESP_OK;
 }
 
+/**
+ * @brief WiFi event handler.
+ * @param arg User argument (unused).
+ * @param event_base Event base.
+ * @param event_id Event ID.
+ * @param event_data Event data.
+ */
 static void event_handler(void *arg, esp_event_base_t event_base,
                           int32_t event_id, void *event_data)
 {

main/wifi.h

@@ -1,3 +1,22 @@
+/**
+ * @file wifi.h
+ * @brief WiFi station mode initialization and management.
+ *
+ * This module initializes WiFi in station mode with static IP
+ * configuration. It handles connection and automatic reconnection.
+ */
+
 #pragma once
 
-void initWifi(void);
+#include "esp_err.h"
+
+/**
+ * @brief Initialize WiFi in station mode.
+ *
+ * Configures WiFi with static IP address from Kconfig settings
+ * and connects to the configured access point. Blocks until
+ * connected or maximum retry count is reached.
+ *
+ * @return ESP_OK on success, ESP_FAIL on error.
+ */
+esp_err_t initWifi(void);