WiFi on in HTTP-mode only, Add batt-threshold to timeout

As initially planned starting wifi only when needed, at change to HTTP mode.
Tested this on breakout board: ESP32 is not getting hot anymore!

Also optimized timeout: only notify "forgot to turn off" when battery is below certain
threshold (e.g. disable when charger is connected over night)

main:
    - dont start wifi at startup anymore
    - remove double-initialization of nvs
      already initialized in wifi.c, thus removed some code
    - optimize comments, logging

control:
    - timeout "forgot to turn off": Add battery threshold
    - start/stop wifi when switching to/from HTTP mode

wifi:
    - split init function to separate functions for NVS and NETIF (more clear in main)
    - optimize log output at nvs init (moved from main)
    - rename start/stop functions, formatting

board_single/main/control.cpp

@@ -12,6 +12,7 @@ extern "C"
 #include "config.h"
 #include "control.hpp"
 #include "chairAdjust.hpp"
+#include "display.hpp" // needed for getBatteryPercent()
 
 
 //used definitions moved from config.h:
@@ -338,6 +339,7 @@ void controlledArmchair::resetTimeout(){
 // notify "power still on" when in IDLE for a very long time (prevent battery drain when forgotten to turn off)
 // this function has to be run repeatedly (can be slow interval)
 #define TIMEOUT_POWER_STILL_ON_BEEP_INTERVAL_MS 5 * 60 * 1000 // beep every 5 minutes for someone to notice
+#define TIMEOUT_POWER_STILL_ON_BATTERY_THRESHOLD_PERCENT 96 // only notify/beep when below certain percentage (prevent beeping when connected to charger)
 // note: timeout durations are configured in config.cpp
 void controlledArmchair::handleTimeout()
 {
@@ -349,6 +351,7 @@ void controlledArmchair::handleTimeout()
              config.timeoutSwitchToIdleMs / 1000,
              config.timeoutNotifyPowerStillOnMs / 1000 / 60 / 60);
 
+    // -- timeout switch to IDLE --
     // timeout to IDLE when not idling already
     if (mode != controlMode_t::IDLE && noActivityDurationMs > config.timeoutSwitchToIdleMs)
     {
@@ -356,15 +359,18 @@ void controlledArmchair::handleTimeout()
         changeMode(controlMode_t::IDLE);
         //TODO switch to previous status-screen when activity detected
     }
+
+    // -- timeout notify "forgot to turn off" --
     // repeatedly notify via buzzer when in IDLE for a very long time to prevent battery drain ("forgot to turn off")
-    // note: ignores user input while in IDLE
-    else if ((esp_log_timestamp() - timestamp_lastModeChange) > config.timeoutNotifyPowerStillOnMs)
+    // also battery charge-level has to be below certain threshold to prevent beeping in case connected to charger
+    // note: ignores user input while in IDLE (e.g. encoder rotation)
+    else if ((esp_log_timestamp() - timestamp_lastModeChange) > config.timeoutNotifyPowerStillOnMs && getBatteryPercent() < TIMEOUT_POWER_STILL_ON_BATTERY_THRESHOLD_PERCENT)
     {
         // beep in certain intervals
         if ((esp_log_timestamp() - timestamp_lastTimeoutBeep) > TIMEOUT_POWER_STILL_ON_BEEP_INTERVAL_MS)
         {
             ESP_LOGW(TAG, "timeout: [TIMEOUT] in IDLE since %.3f hours -> beeping", (float)(esp_log_timestamp() - timestamp_lastModeChange) / 1000 / 60 / 60);
-            // TODO dont beep at certain times ranges (e.g. at night)
+            // TODO dont beep at certain time ranges (e.g. at night)
             timestamp_lastTimeoutBeep = esp_log_timestamp();
             buzzer->beep(6, 100, 50);
         }
@@ -407,6 +413,11 @@ void controlledArmchair::changeMode(controlMode_t modeNew) {
             buzzer->beep(1,200,100);
 			break;
 
+        case controlMode_t::HTTP:
+            ESP_LOGW(TAG, "switching from HTTP mode -> stopping wifi-ap");
+            wifi_stop_ap();
+            break;
+
         case controlMode_t::MASSAGE:
             ESP_LOGW(TAG, "switching from MASSAGE mode -> restoring fading, reset frozen input");
             //TODO: fix issue when downfading was disabled before switching to massage mode - currently it gets enabled again here...
@@ -454,6 +465,11 @@ void controlledArmchair::changeMode(controlMode_t modeNew) {
             buzzer->beep(1, 900, 0);
             break;
 
+        case controlMode_t::HTTP:
+            ESP_LOGW(TAG, "switching to HTTP mode -> starting wifi-ap");
+            wifi_start_ap();
+            break;
+
         case controlMode_t::ADJUST_CHAIR:
             ESP_LOGW(TAG, "switching to ADJUST_CHAIR mode: turning both motors off, beep");
             idleBothMotors();

board_single/main/display.hpp

@@ -59,6 +59,9 @@ typedef enum displayStatusPage_t {STATUS_SCREEN_OVERVIEW=0, STATUS_SCREEN_SPEED,
 // get precise battery voltage (using lookup table)
 float getBatteryVoltage();
 
+// get battery charge level in percent (using lookup table as discharge curve)
+float getBatteryPercent();
+
 // function to select one of the defined status screens which are shown on display when not in MENU mode
 void display_selectStatusPage(displayStatusPage_t newStatusPage);
 

board_single/main/main.cpp

@@ -107,7 +107,6 @@ nvs_handle_t nvsHandle;
 //=================================
 //initialize spi flash filesystem (used for webserver)
 void init_spiffs(){
-    ESP_LOGW(TAG, "initializing spiffs...");
     esp_vfs_spiffs_conf_t esp_vfs_spiffs_conf = {
         .base_path = "/spiffs",
         .partition_label = NULL,
@@ -194,35 +193,29 @@ extern "C" void app_main(void) {
 	gpio_set_direction(GPIO_NUM_17, GPIO_MODE_OUTPUT);
 	gpio_set_level(GPIO_NUM_17, 1);                                                      
 
-	//--- initialize nvs-flash and netif (needed for wifi) ---
-	ESP_LOGW(TAG,"initializing wifi...");
-	wifi_initNvs_initNetif();
+	//--- initialize nvs-flash and netif ---
+	ESP_LOGW(TAG,"initializing NVS...");
+	wifi_initNvs(); //needed for wifi and persistent config variables
+	ESP_LOGW(TAG,"initializing NETIF...");
+	wifi_initNetif(); // needed for wifi
 
 	//--- initialize spiffs ---
-	init_spiffs();
+    ESP_LOGW(TAG, "initializing SPIFFS...");
+	init_spiffs(); // used by httpd server
 
 	//--- initialize and start wifi ---
-	ESP_LOGW(TAG,"starting wifi...");
-	//wifi_init_client(); //connect to existing wifi
-	wifi_init_ap(); //start access point
-	ESP_LOGD(TAG,"done starting wifi");
+	// Note: now started only when switching to HTTP mode in control.cpp
+	// ESP_LOGW(TAG,"starting wifi...");
+	// wifi_start_client(); //connect to existing wifi (dropped)
+	// wifi_start_ap(); //start access point
 
 	//--- initialize encoder ---
 	const QueueHandle_t encoderQueue = encoder_init(&encoder_config);
 
-	//--- initialize nvs-flash ---  (for persistant config values)
-	ESP_LOGW(TAG, "initializing nvs-flash...");
-	esp_err_t err = nvs_flash_init();
-	if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND)
-	{
-		ESP_LOGE(TAG, "NVS truncated -> deleting flash");
-		// Retry nvs_flash_init
-		ESP_ERROR_CHECK(nvs_flash_erase());
-		err = nvs_flash_init();
-	}
-	ESP_ERROR_CHECK(err);
 	//--- open nvs-flash ---
-	err = nvs_open("storage", NVS_READWRITE, &nvsHandle);
+	// note: nvs already initialized in wifi_initNvs()
+    ESP_LOGW(TAG, "opening NVS-handle...");
+	esp_err_t err = nvs_open("storage", NVS_READWRITE, &nvsHandle); // this handle is passed to all tasks for accessing nvs
 	if (err != ESP_OK)
 		ESP_LOGE(TAG, "Error (%s) opening NVS handle!\n", esp_err_to_name(err));