include "wifi-networks.cfg";

DEBUG=0;
SLEEP=5;
SCAN_TIME_WAIT=30;
CFG_TIME_WAIT=120;

string enc_to_cfg(enc) {
    switch(enc) {
    case "WPA2-SAE":
    enc = "wpa3";
    break;
    case "WPA2-PSK":
    enc = "wpa2";
    break;
    default:
    enc = "wpa2";
    if(DEBUG) nb_syslog("wifi swticher: undefinded enc: %s, using wpa2...", enc);
    }
    return enc;
}

while(1) {
    // we get the current state of wanlink2 (wlan)
    wan_status=nb_status("wan");
    state=struct_get(wan_status, "WANLINK2_STATE");
    if(DEBUG) nb_syslog("wifi switcher: current state = %s", state);

    // in case the wlan connection is up or dialing we do not start a new scan
    if (state != "down") {
        sleep(SLEEP);
        continue;
    }

    // only scan networks if last scan is more than SCAN_TIME_WAIT in the past
    if(DEBUG) nb_syslog("wifi switcher: last scan was %ds ago", uptime() - SCAN_TIME);
    if (uptime() - SCAN_TIME > SCAN_TIME_WAIT){
        SCAN_TIME=uptime();
        scan_res = nb_scan_networks("WLAN1");
        if(DEBUG) nb_syslog("wifi switcher: scanning WLAN networks took %ds", uptime() - SCAN_TIME);
    }
    found=false;
    i=1;

    // get all the wifi information from the ap
    do {
        ssid=   struct_get(scan_res, sprintf("NETWORK%d_SSID", i));
        chipher=struct_get(scan_res, sprintf("NETWORK%d_CIPHER_1", i));
        enc=    struct_get(scan_res, sprintf("NETWORK%d_ENCRYPTION_1", i));
        /* if(DEBUG) nb_syslog("wifi switcher: position in do loop i = %d",i); */
        i++;
        for (j=0; j<length(wifi_list); j++) {
            if (ssid == wifi_list[j][0]) {
                if(DEBUG) nb_syslog("wifi switcher: configuring wifi with ssid: %s", ssid);
                cfg=sprintf("wlan.0.client.0.ssid=%s ", ssid);
                cfg=strcat(cfg, sprintf("wlan.0.client.0.secmode=wpa-psk "));
                cfg=strcat(cfg, sprintf("wlan.0.client.0.secproto=%s ", enc_to_cfg(enc)));
                cfg=strcat(cfg, sprintf("wlan.0.client.0.cipher=%s ", tolower(chipher)));
                cfg=strcat(cfg, sprintf("wlan.0.client.0.minqual=2 "));
                cfg=strcat(cfg, sprintf("wlan.0.client.0.minrssi=-99 "));
                cfg=strcat(cfg, sprintf("wlan.0.client.0.psk=%s", wifi_list[j][1]));

                // only apply config if last config set is more tan CFG_TIME_WAIT in the past
                if(DEBUG) nb_syslog("wifi switcher: last config set was %ds ago", uptime() - CFG_TIME);
                if (uptime() - CFG_TIME > CFG_TIME_WAIT){
                    CFG_TIME = uptime();
                    nb_config_set(cfg);
                    if(DEBUG) nb_syslog("wifi switcher: new wlan config got setup");
                }
                found=true;
                break;
            }
        }
        if(found) break;
    } while ( !is_void(ssid) );
    sleep(SLEEP);
}