max80_fw/esp32/max80/wifi.cpp

#include "common.h"
#include "WiFi.h"
#include "wifi.h"
#include "storage.h"
#include "httpd.h"

#include <lwip/dns.h>
#include <lwip/inet.h>
#include <lwip/apps/sntp.h>
#include <esp_sntp.h>

static String ssid        = "";
static String password    = "";
static String otaPassword = "";
static String hostname    = "max80";
static String DNSServer   = "";
static String SNTPServer  = "";
static String TimeZone    = "CET-1CEST,M3.5.0,M10.5.0/3"; // Sweden

static void sntp_sync_cb(struct timeval *tv)
{
    static uint8_t prev_sync_status = SNTP_SYNC_STATUS_RESET;
    uint8_t sync_status = sntp_get_sync_status();
    
    switch (sync_status) {
    case SNTP_SYNC_STATUS_RESET:
	sntp_set_sync_mode(SNTP_SYNC_MODE_IMMED); // Until first sync
	if (prev_sync_status != sync_status) {
	    printf("[SNTP] time synchronization lost\n");
	}
	break;
    case SNTP_SYNC_STATUS_COMPLETED:
	sntp_set_sync_mode(SNTP_SYNC_MODE_SMOOTH); // After successful sync
	if (prev_sync_status != sync_status) {
	    char timebuf[64];
	    const struct tm *tm = localtime(&tv->tv_sec);
	    strftime(timebuf, sizeof timebuf, "%a %Y-%m-%d %H:%M:%S %z", tm);
	    printf("[SNTP] Time synchronized: %s\n", timebuf);
	}
	break;
    default:
	break;
    }

    prev_sync_status = sync_status;
}

static void my_sntp_start()
{
    sntp_set_time_sync_notification_cb(sntp_sync_cb);
    sntp_setoperatingmode(SNTP_OPMODE_POLL);
    sntp_servermode_dhcp(1);
    sntp_set_sync_mode(SNTP_SYNC_MODE_IMMED); // Until first sync
    sntp_init();
}

static bool services_started;

static void stop_services(void)
{
    if (services_started) {
	esp_unregister_shutdown_handler(stop_services);
	my_httpd_stop();
	services_started = false;
    }
}

static inline bool invalid_ip(const ip_addr_t *ip)
{
    return !memcmp(ip, &ip_addr_any, sizeof *ip);
}

static void start_services(void)
{
    /* Always run after connect */
    const ip_addr_t *dns_ip = dns_getserver(0);
    if (invalid_ip(dns_ip)) {
	/* No DNS server from DHCP? */
	ip_addr_t addr;
	if (inet_aton(DNSServer.c_str(), &addr)) {
	    dns_setserver(0, &addr);
	}
    }

    dns_ip = dns_getserver(0);
    printf("[DNS]  DNS server: %s\n", inet_ntoa(*dns_ip));
 
    // If Arduino supported both of these at the same that would be
    // awesome, but it requires ESP-IDF reconfiguration...
    const ip_addr_t *sntp_ip = sntp_getserver(0);

    if (invalid_ip(sntp_ip) && !SNTPServer.isEmpty())
	sntp_setservername(0, SNTPServer.c_str());

    sntp_ip = sntp_getserver(0);
    printf("[SNTP] Time server: %s\n", inet_ntoa(*sntp_ip));

    /* Only run on first start */
    if (!services_started) {
	services_started = true;
	my_httpd_start();
	esp_register_shutdown_handler(stop_services);
    }
}

static String wifi_local_ip(void)
{
    return WiFi.localIP().toString();
}

static void WiFiEvent(WiFiEvent_t event, WiFiEventInfo_t info)
{
    bool retry = false;
    bool connected = false;

    switch (event) {
    case ARDUINO_EVENT_WIFI_READY:
	printf("[WIFI] Interface ready\n");
	break;
    case ARDUINO_EVENT_WIFI_SCAN_DONE:
	printf("[WIFI] Completed scan for access points\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_START:
	printf("[WIFI] Client started\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_STOP:
	printf("[WIFI] Clients stopped\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_CONNECTED:
	printf("[WIFI] Connected to access point\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_DISCONNECTED:
	printf("[WIFI] Disconnected from WiFi access point\n");
	retry = true;
	break;
    case ARDUINO_EVENT_WIFI_STA_AUTHMODE_CHANGE:
	printf("[WIFI] Authentication mode of access point has changed\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_GOT_IP:
	printf("[WIFI] Obtained IP address: %s\n", wifi_local_ip().c_str());
	connected = true;
	break;
    case ARDUINO_EVENT_WIFI_STA_LOST_IP:
	printf("[WIFI] Lost IP address and IP address is reset to 0\n");
	retry = true;
	break;
    case ARDUINO_EVENT_WPS_ER_SUCCESS:
	printf("[WIFI] WiFi Protected Setup (WPS): succeeded in enrollee mode\n");
	break;
    case ARDUINO_EVENT_WPS_ER_FAILED:
	printf("[WIFI] WiFi Protected Setup (WPS): failed in enrollee mode\n");
	break;
    case ARDUINO_EVENT_WPS_ER_TIMEOUT:
	printf("[WIFI] WiFi Protected Setup (WPS): timeout in enrollee mode\n");
	break;
    case ARDUINO_EVENT_WPS_ER_PIN:
	printf("[WIFI] WiFi Protected Setup (WPS): pin code in enrollee mode\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_START:
	printf("[WIFI] Access point started\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_STOP:
	printf("[WIFI] Access point stopped\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_STACONNECTED:
	printf("[WIFI] Client connected\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_STADISCONNECTED:
	printf("[WIFI] Client disconnected\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_STAIPASSIGNED:
	printf("[WIFI] Assigned IP address to client\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_PROBEREQRECVED:
	printf("[WIFI] Received probe request\n");
	break;
    case ARDUINO_EVENT_WIFI_AP_GOT_IP6:
	printf("[WIFI] AP IPv6 is preferred\n");
	break;
    case ARDUINO_EVENT_WIFI_STA_GOT_IP6:
	printf("[WIFI] STA IPv6 is preferred\n");
	connected = true;
	break;
    case ARDUINO_EVENT_ETH_GOT_IP6:
	printf("[ETH] Ethernet IPv6 is preferred\n");
	connected = true;
	break;
    case ARDUINO_EVENT_ETH_START:
	printf("[ETH] Ethernet started\n");
	break;
    case ARDUINO_EVENT_ETH_STOP:
	printf("[ETH] Ethernet stopped\n");
	break;
    case ARDUINO_EVENT_ETH_CONNECTED:
	printf("[ETH] Ethernet connected\n");
	break;
    case ARDUINO_EVENT_ETH_DISCONNECTED:
	printf("[ETH] Ethernet disconnected\n");
	retry = true;
	break;
    case ARDUINO_EVENT_ETH_GOT_IP:
	printf("[ETH] Obtained IP address: %s\n", wifi_local_ip().c_str());
	connected = true;
	break;
    default:
	break;
    }

    /* Maybe need to do these in a different thread? */

    if (connected) {
	start_services();
    }

    if (retry) {
	WiFi.disconnect();
	WiFi.begin();
    }
}

void SetupWiFi() {
    services_started = false;

    ssid = GetWifiSSID();
    password = GetWifiPassword();
    hostname = GetHostname();

    if (!TimeZone.isEmpty()) {
	printf("[INFO] Setting TZ = %s\n", TimeZone.c_str());
	setenv("TZ", TimeZone.c_str(), 1);
	tzset();
    }
    my_sntp_start();
    
    printf("[INFO] Setting up WiFi\n");
    printf("[INFO] SSID: %s\n", ssid.c_str());

    WiFi.onEvent(WiFiEvent);

    if (WiFi.getMode() != WIFI_STA) {
	WiFi.mode(WIFI_STA);
	delay(10);
    }

    if (WiFi.SSID() != ssid || WiFi.psk() != password) {
	printf("[INFO] WiFi config changed.\n");
	// ... Try to connect to WiFi station.
	WiFi.begin(ssid.c_str(), password.c_str());
    } else {
	WiFi.begin();
    }

    WiFi.setAutoReconnect(true);
    WiFi.setHostname(hostname.c_str());
}