#include <stdio.h>
#include <ESP8266WebServer.h>

#define HTTP_REST_PORT 80
#define WIFI_RETRY_DELAY 500
#define MAX_WIFI_INIT_RETRY 50

struct Pulsanti  {
    byte id;
    byte status1;
    byte status2;
} pulsanti_resource;

const char* wifi_ssid = "xxx";
const char* wifi_passwd = "xx";

ESP8266WebServer http_rest_server(HTTP_REST_PORT);

void init_pulsanti_resource()
{
    pulsanti_resource.id = 1;
    pulsanti_resource.status1 = LOW;
    pulsanti_resource.status2 = LOW;
}

int init_wifi() {
    int retries = 0;

    Serial.println("Connecting to WiFi AP..........");

    WiFi.mode(WIFI_STA);
    WiFi.begin(wifi_ssid, wifi_passwd);
    // check the status of WiFi connection to be WL_CONNECTED
    while ((WiFi.status() != WL_CONNECTED) && (retries < MAX_WIFI_INIT_RETRY)) {
        retries++;
        delay(WIFI_RETRY_DELAY);
        Serial.print("#");
    }
    return WiFi.status(); // return the WiFi connection status
}

void get_pulsanti() {
    if (pulsanti_resource.id == 0)
        http_rest_server.send(204);
    else {
        http_rest_server.send(200, "text/html", String(pulsanti_resource.status1) + " " + String(pulsanti_resource.status2));
    }
}

void config_rest_server_routing() {
    http_rest_server.on("/", HTTP_GET, []() {
        http_rest_server.send(200, "text/html",
            "Welcome to the ESP8266 REST Web Server");
    });
    http_rest_server.on("/pulsanti", HTTP_GET, get_pulsanti);
}

void setup(void) {
    Serial.begin(115200);

    init_pulsanti_resource();
    if (init_wifi() == WL_CONNECTED) {
        Serial.print("Connetted to ");
        Serial.print(wifi_ssid);
        Serial.print("--- IP: ");
        Serial.println(WiFi.localIP());
    }
    else {
        Serial.print("Error connecting to: ");
        Serial.println(wifi_ssid);
    }

    config_rest_server_routing();

    http_rest_server.begin();
    Serial.println("HTTP REST Server Started");
}

void loop(void) {
    http_rest_server.handleClient();
}