//ESP32 Wroover module
#include <HTTPClient.h>
#include <WiFi.h>
#include <WebServer.h>
WebServer server(80);
//=================
#include "driver/rtc_io.h"
//=================
#include <WiFiClient.h>
#include <EEPROM.h> // for store settings

#include "AsyncStream.h"
AsyncStream<4096> serial(&Serial, '~', 50);
#define LOOPS_CNT_AFTER_INT2 15
#define MIN_READ_DATA_SIZE 79
uint16_t loops_cnt=0;
const char *ap_id, *hipp;
//#define ESP_READY_DURATION 10

//======== BTNS AND RTC VAR CONF ===================
#define BUTTON_PIN_BITMASK 0x1000  //12 pin, wake up btn
RTC_DATA_ATTR int firststart = true;
//RTC_DATA_ATTR int firststart = false;
int btnsList[] = {14, -1}; // config btn
//==========================================


void pisk(int n)
{
  return;
}

const int PIN_CONF = 14; //2;
const int PIN_READY = 16; //0;
boolean conf = false;
boolean wifi_started = false;
boolean blink_mode = false;
boolean wait_serial = true;
uint32_t s_start=0;


void setup() {
  Serial.begin(115200); 
  //Serial.begin(57600);
  //Serial.begin(19200);
  //Serial.begin(9600);
  //Serial.begin(2400);
  while (!Serial) {
    delay(10); // will pause Zero, Leonardo, etc until serial console opens
  }
  pinMode(PIN_CONF, INPUT);
  pinMode(PIN_READY, OUTPUT);
  Serial.println("START");
  // check config pin
  if ( digitalRead(PIN_CONF) == HIGH ) { // button pressed
    conf = true;
    Serial.println("Button pressed");
    Serial.println("CONFIG MODE");
    Serial.println("CM");
  }else{
    conf = false;
    //Serial.println("Button NOT pressed");
    //Serial.println("WORK MODE");
    Serial.println("WM");
  }
  // Start AP/webserver or try connect to WiFi point
  if(conf){ // Режим SoftAP
    startWiFiServer();
    Serial.println("startWiFiServer");
    digitalWrite(PIN_READY, HIGH);
    delay(200);
    digitalWrite(PIN_READY, LOW);
    delay(200);
    digitalWrite(PIN_READY, HIGH);
    delay(200);
    digitalWrite(PIN_READY, LOW);
    delay(200);
    digitalWrite(PIN_READY, HIGH); // поятоянно горящий светодиод - признак режима конфигурации
    return;
  }
  if(firststart){
    // read world time
    Serial.println("Start wifi  "+String(millis()));
    wifi_started = startWiFiClient(); // time reading by firststart flag
    if(wifi_started){
      Serial.println("wifi started "+String(millis()));
      digitalWrite(PIN_READY, HIGH);
      firststart = false;
    }else{
      Serial.println("can not started WiFi");
      blink_mode=true;
    }
  }else{
    digitalWrite(PIN_READY, HIGH);
  }
  
  Serial.println("BGN");
  // готов принимать данные
  s_start = millis();
  loops_cnt=0;
  Serial.println("Start. "+String(millis()));
}

//const char* httpuri ="http://www.bannerhost.ru/cgi-bin/esp01";
const char* httpuri; // ="http://195.201.126.70:8080/sbadat";
void loop() {
  if(blink_mode){
    digitalWrite(PIN_READY, HIGH);
    delay(200);
    digitalWrite(PIN_READY, LOW);
    delay(200);
    return;
  }
  if(conf){
    // режим конфигурации
    server.handleClient();
  }else{
    if(firststart){
      firststart = false;
      Serial.println("firststart");
      Serial.println("goto sleep");
      // sleep
      // уходим в сон
      //esp_sleep_enable_ext1_wakeup(BUTTON_PIN_BITMASK,ESP_EXT1_WAKEUP_ANY_HIGH);
      esp_sleep_enable_ext0_wakeup(GPIO_NUM_12,1);
      rtc_gpio_pullup_dis(GPIO_NUM_12);
      rtc_gpio_pulldown_en(GPIO_NUM_12);
      //Go to sleep now
      //Serial.println("Going to sleep now");
      esp_deep_sleep_start();
      Serial.println("This will never be printed");
      return;
    }
    // режим приёма данных и отправки на сервер
    int sa_steps=0;
    //while(!serial.available()){
    //  sa_steps++;
    //}
    if (wait_serial) {wait_serial=false;Serial.println("wait serial");}
    if (serial.available()) {     // если данные получены
      wait_serial=true;
      time_t sending_time = time(nullptr);
      if(!wifi_started){
        Serial.println("Start wifi: "+String(millis()));
        wifi_started = startWiFiClient(); // time reading by firststart flag
        if(wifi_started){
          Serial.println("wifi started: "+String(millis()));
        }else{
          Serial.println("can not started WiFi");
          blink_mode=true;
          return;
        }
      }
      uint32_t reading_time = millis() - s_start;
      int data_len = strlen(serial.buf);
      boolean get_last_loop_flag = false;
      if(serial.buf[0] == 'L') {
        get_last_loop_flag = true;
        Serial.println("get_last_loop_flag");
      }
      Serial.println("data readed: "+String(millis())+", data size = "+String(data_len));
      if(data_len < MIN_READ_DATA_SIZE){
        Serial.println("data size too small!");
        return;
      }
      digitalWrite(PIN_READY, LOW); // данные приняты для отправки
      // start WiFi client
      uint32_t wifi_start_time = millis();
      Serial.println("start wifi");
      if(wifi_started){
        Serial.println("wifi started");
        // send buf to host
        WiFiClient client;
        String ds = ap_id;
        //ds += ", uart time: ";
        //ds += String(reading_time);
        //ds += ", WiFi connection time: ";
        //ds += String(millis() - wifi_start_time);
        ds += ", data size: ";
        ds += String(data_len);
        ds += ", sending time: ";
        char fstr[32];
        sprintf(fstr,"%lu", sending_time);
        ds += fstr;
        HTTPClient http;    //Объявить объект класса HttpClient
        http.begin(client, httpuri);      //Укажите адрес запроса
        http.addHeader("Content-Type", "text/plain");  //Укажите заголовок типа содержимого
        //http.addHeader("Title", ap_id);  // так передадим ID датчика
        Serial.println("Send data:");
        Serial.println(ds);
        Serial.println(serial.buf);
        http.addHeader("Title", ds);  // так передадим ID датчика
        int httpCode = http.POST(serial.buf);   //Отправьте запрос
        String payload = http.getString();                  //Получите полезную нагрузку ответа
        Serial.println("HTTP answer:");
        Serial.println(httpCode);   //Распечатать код возврата HTTP
        Serial.println(payload);    //Полезная нагрузка для ответа на запрос печати
        http.end();  //Закрыть соединение
      }
      digitalWrite(PIN_READY, HIGH);
      // NON STOP VERSION //loops_cnt++;
      Serial.println("loops_cnt = "+String(loops_cnt));
      if((loops_cnt >= LOOPS_CNT_AFTER_INT2) || get_last_loop_flag){
        loops_cnt=0;
        firststart = true;
        Serial.println("goto sleep");
        stopWiFiClient();
        delay(100);
        digitalWrite(PIN_READY, LOW);
        // засыпаем, пока на RST не моргнут LOW
        //ESP.deepSleep(0); 
        // уходим в сон, пока не включится 12я кнопка
        //esp_sleep_enable_ext1_wakeup(BUTTON_PIN_BITMASK,ESP_EXT1_WAKEUP_ANY_HIGH);
        esp_sleep_enable_ext0_wakeup(GPIO_NUM_12,1);
        rtc_gpio_pullup_dis(GPIO_NUM_12);
        rtc_gpio_pulldown_en(GPIO_NUM_12);
        //Go to sleep now
        //Serial.println("Going to sleep now");
        esp_deep_sleep_start();
        Serial.println("This will never be printed");
      }
    }
  }
}

void stopWiFiClient()
{
  WiFi.disconnect();
  Serial.println("WiFi disconnected");
}
#define CONN_TRY_LIMIT 5
bool startWiFiClient()
{
  blink_mode = false;
  //WiFi.forceSleepWake();
  // try connect to WiFi point
  byte len_ssid, len_pass, len_id, len_hipp;
  EEPROM.begin(98);
  len_hipp = EEPROM.read(94);
  len_id   = EEPROM.read(95);
  len_ssid = EEPROM.read(96);
  len_pass = EEPROM.read(97);
  if((len_ssid > 0) && (len_pass > 0) && (len_id > 0) && (len_hipp > 0) && ((len_id+len_ssid+len_pass+len_hipp)<=94)){ 
    // Режим STATION 
    WiFi.mode( WIFI_STA);
    unsigned char* buf = new unsigned char[100];
    for(byte n = 0; n < len_ssid; n++) buf[n] = char(EEPROM.read(n));
    buf[len_ssid] = '\x0';
    const char *ssid  = (const char*)buf;
    unsigned char *buf_pass = buf+len_ssid+1;
    for(byte n = 0; n < len_pass; n++) buf_pass[n] = char(EEPROM.read(n + len_ssid));
    buf_pass[len_pass] = '\x0';
    const char *pass  = (const char*)buf_pass;
    unsigned char *buf_id = buf_pass+len_pass+1;
    for(byte n = 0; n < len_id; n++) buf_id[n] = char(EEPROM.read(n + len_ssid + len_pass));
    buf_id[len_id] = '\x0';
    ap_id  = (const char *)buf_id;
    //Serial.print("Try connect to ");
    //Serial.println(ssid);
    //Serial.println(" / ");
    //Serial.println(pass);
    WiFi.begin(ssid, pass);
    // Wait for connection
    // read hipp
    unsigned char *buf_hipp = buf_id+len_id+1;
    for(byte n = 0; n < len_hipp; n++) buf_hipp[n] = char(EEPROM.read(n + len_ssid + len_pass + len_id));
    buf_hipp[len_hipp] = '\x0';
    hipp  = (const char *)buf_hipp;
    httpuri = hipp;
    int try_cnt = 0;
    while ( WiFi.status() != WL_CONNECTED ) {
      try_cnt++;
      Serial.print(".");
      delay ( 100 );
    }
    //Serial.println("Connected"); 
    if(firststart){
      // Получение мирового времени
      //Serial.print("Retrieving time: ");
      configTime(0, 0, "pool.ntp.org"); // get UTC time via NTP
      time_t now = time(nullptr);
      while (now < 24 * 3600)
      {
        //Serial.print(".");
        digitalWrite(PIN_READY, HIGH);
        delay(20);
        digitalWrite(PIN_READY, LOW);
        delay(80);
        now = time(nullptr);
        //pisk(1);
      }
      //Serial.println(now);
      firststart = false;
    }
    return(true);
  }
  blink_mode = true;
  return(false);
}

void startWiFiServer()
{
    const char *ssid_ap = "SmaptBedPoint";
    WiFi.mode(WIFI_AP);
    WiFi.softAP(ssid_ap);
    delay(2000);
    IPAddress myIP = WiFi.softAPIP();
    server.on("/", handleRoot);
    server.on("/ok", handleOk);
    server.begin();
    //Serial.print("AP IP address: ");
    //Serial.println(myIP);
    //Serial.println("HTTP server started");
}

//================================
// веб-сервер первичной настройки 
//================================
String html_header = "<html>\
  <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">\
  <head>\
    <title>ESP32_NEW_BED Settings</title>\
    <style>\
      body { background-color: #cccccc; font-family: Arial, Helvetica, Sans-Serif; Color: #000088; }\
    </style>\
  </head>";
void handleRoot() {
  digitalWrite(PIN_READY, HIGH);
  String str = "";
  str += html_header;
  // IntelNUC - http://192.168.0.108:8080/
  // Doich - http://195.201.126.70:8080/sbadat
  str += "<body><H3>\
    <form method=\"POST\" action=\"ok\">\
      <input name=\"ssid\" value=\"TP-Link_7C38\"> WIFI Net</br>\
      <input name=\"pswd\" value=\"36929092\"> Password</br></br>\
      <input name=\"id\"> Tablet ID</br></br>\
      <input name=\"hipp\" value=\"http://activity206.li.ru/cgi-bin/radar.sh\"> HOST_IP:PORT</br></br>\
      <input type=SUBMIT value=\"Save settings\">\
    </form>\
  </H3></body>\
  </html>";
  server.send ( 200, "text/html", str );
}

void handleOk(){
  String ssid_ap, pass_ap, id_ap, hipp_ap;
  unsigned char* buf = new unsigned char[64];
  String str = "";
  str += html_header;
  str += "<body>";
  ssid_ap = server.arg(0);
  pass_ap = server.arg(1);
  id_ap   = server.arg(2);
  hipp_ap   = server.arg(3);
  if((ssid_ap != "") && ((id_ap.length() + ssid_ap.length() + pass_ap.length() + hipp_ap.length()) < 94)){
    EEPROM.begin(98);
    EEPROM.write(94,hipp_ap.length());
    EEPROM.write(95,id_ap.length());
    EEPROM.write(96,ssid_ap.length());
    EEPROM.write(97,pass_ap.length());
    // store ssid_ap
    ssid_ap.getBytes(buf, ssid_ap.length() + 1);
    for(byte i = 0; i < ssid_ap.length(); i++)
      EEPROM.write(i, buf[i]);
    // store pass_ap
    pass_ap.getBytes(buf, pass_ap.length() + 1);
    int dlt = ssid_ap.length();
    for(byte i = 0; i < pass_ap.length(); i++)
      EEPROM.write(i + dlt, buf[i]);
    // store id_ap
    id_ap.getBytes(buf, id_ap.length() + 1);
    dlt += pass_ap.length();
    for(byte i = 0; i < id_ap.length(); i++)
      EEPROM.write(i + dlt, buf[i]);
    // store hipp_ap
    hipp_ap.getBytes(buf, hipp_ap.length() + 1);
    dlt += id_ap.length();
    for(byte i = 0; i < hipp_ap.length(); i++)
      EEPROM.write(i + dlt, buf[i]);
    // end store
    EEPROM.commit();
    EEPROM.end();
    //Serial.println("Store to EEPROM WiFi SSID " + ssid_ap +", WiFi PASSWD " + pass_ap +", Tablet ID " + id_ap);
    str +="Configuration saved in FLASH</br>\
    The module is now restarting automatically for WiFi connection</p></br></br>"; //\
    //<a href=\"/\">Return</a> to settings page</br>";
    str +=  "WiFi SSID [" + ssid_ap +"], WiFi PASSWD [" + pass_ap +"], device ID [" + id_ap + "], Host IP and Port [" + hipp_ap + "]";
    str += "</body></html>";
    server.send ( 200, "text/html", str );
    delay(1000);
    digitalWrite(PIN_READY, LOW);
    //ESP.restart();
  }else{
    str += "No WIFI Net</br>\
    <a href=\"/\">Return</a> to settings page</br>";
    str += "</body></html>";
    server.send ( 200, "text/html", str );
    pisk(7);
  }
  //str += "</body></html>";
  //server.send ( 200, "text/html", str );
}