#include "LoRaWan_APP.h"
#include "Arduino.h"
#include <Wire.h>
#include "softSerial.h"
#include "TinyGPS++.h"

/*
 * set LoraWan_RGB to 1,the RGB active in loraWan
 * RGB red means sending;
 * RGB green means received done;
 */

#ifndef LoraWan_RGB
#define LoraWan_RGB 0
#endif

#define RF_FREQUENCY                                915000000 // Hz

#define TX_OUTPUT_POWER                             14        // dBm

#define LORA_BANDWIDTH                              0         // [0: 125 kHz,
                                                              //  1: 250 kHz,
                                                              //  2: 500 kHz,
                                                              //  3: Reserved]
#define LORA_SPREADING_FACTOR                       8         // [SF7..SF12]
#define LORA_CODINGRATE                             4         // [1: 4/5,
                                                              //  2: 4/6,
                                                              //  3: 4/7,
                                                              //  4: 4/8]
#define LORA_PREAMBLE_LENGTH                        8         // Same for Tx and Rx
#define LORA_SYMBOL_TIMEOUT                         0         // Symbols
#define LORA_FIX_LENGTH_PAYLOAD_ON                  false
#define LORA_IQ_INVERSION_ON                        false
#define LORA_SYNC_WORD                              0x12 //sync word to join two LoRa devices


#define RX_TIMEOUT_VALUE                            1000
#define BUFFER_SIZE                                 30 // Define the payload size here

char txpacket[BUFFER_SIZE];
char rxpacket[BUFFER_SIZE];

#define timetosleep 1000
#define timetowake 20000
static TimerEvent_t sleep;
static TimerEvent_t wakeup;
uint8_t lowpower;
int gpslowpower;

static RadioEvents_t RadioEvents;

double txNumber;
int gtx = GPIO5;
int grx = GPIO3;
int16_t rssi,rxSize;
void  DoubleToString( char *str, double double_num,unsigned int len);
softSerial ss(grx, gtx);
TinyGPSPlus gps;

uint8_t slow_gps[] = {0xB5, 0x62, 0x06, 0x08, 0x06, 0x00, 0x10, 0x27, 0x01, 0x00, 0x01, 0x00, 0x4D, 0xDD, 0xB5, 0x62, 0x06, 0x08, 0x00, 0x00, 0x0E, 0x30};
uint8_t reset_gps[] = {0xB5, 0x62, 0x06, 0x04, 0x04, 0x00, 0xFF, 0x87, 0x01, 0x00, 0x95, 0xF7};
uint8_t low_power_gps[] = {0xB5, 0x62, 0x06, 0x04, 0x04, 0x00, 0x00, 0x00, 0x08, 0x00, 0x16, 0x74};
uint8_t fast_gps[] = {0xB5, 0x62, 0x06, 0x08, 0x06, 0x00, 0xF4, 0x01, 0x01, 0x00, 0x01, 0x00, 0x0B, 0x77};
uint8_t cold_start_gps[] = {0xB5, 0x62, 0x06, 0x04, 0x04, 0x00, 0xFF, 0xFF, 0x02, 0x00, 0x0E, 0x61};
uint8_t pedest_mode_gps[] = {0xB5, 0x62, 0x06, 0x24, 0x24, 0x00, 0xFF, 0xFF, 0x03, 0x03, 0x00, 0x00, 0x00, 0x00, 0x10, 0x27, 0x00, 0x00, 0x05, 0x00, 0xFA, 0x00, 0xFA, 0x00, 0x64, 0x00, 0x2C, 0x01, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x4F, 0x82, 0xB5, 0x62, 0x06, 0x24, 0x00, 0x00, 0x2A, 0x84};
uint8_t hard_reset_gps[] = {0xB5, 0x62, 0x06, 0x09, 0x0D, 0x00, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x00, 0x00, 0x07, 0x1F, 0x9E};
uint8_t low_baud_gps[] = {0xb5, 0x62, 0x06, 0x00, 0x14, 0x00, 0x01, 0x00, 0x00, 0x00, 0xd0, 0x08, 0x00, 0x00, 0xc0, 0x12, 0x00, 0x00, 0x07, 0x00, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0xd3, 0xfc, 0xb5, 0x62, 0x06, 0x00, 0x01, 0x00, 0x01, 0x08, 0x22};
uint8_t GPSStandby[] = {0xB5, 0x62, 0x02, 0x41, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x4D, 0x3B};
 //the pins that the GPS is connected to

void setup() {
    delay(500);
    Serial.begin(115200);
    ss.begin(9600);
    rssi=0;
    lowpower = 0;

    Radio.Init( &RadioEvents ); //start the radio with the parameters define at the top
    Radio.SetChannel( RF_FREQUENCY );
    Radio.SetSyncWord(LORA_SYNC_WORD);
    Radio.SetTxConfig( MODEM_LORA, TX_OUTPUT_POWER, 0, LORA_BANDWIDTH,
                                   LORA_SPREADING_FACTOR, LORA_CODINGRATE,
                                   LORA_PREAMBLE_LENGTH, LORA_FIX_LENGTH_PAYLOAD_ON,
                                   true, 0, 0, LORA_IQ_INVERSION_ON, 3000 );

    TimerInit( &sleep, OnSleep );
    TimerInit( &wakeup, OnWakeup );
    delay(500);
    OnWakeup();
   }

void loop()
{
  if(lowpower > 0)
  {
  //note that LowPower_Handler() run six times the mcu into lowpower mode;
  lowPowerHandler();
  //ss.flush();
  }
}

void  DoubleToString( char *str, double double_num,unsigned int len) {
  double fractpart, intpart;
  fractpart = modf(double_num, &intpart);
  fractpart = fractpart * (pow(10,len));
  sprintf(str + strlen(str),"%d", (int)(intpart)); //Integer part
  sprintf(str + strlen(str), ".%d", (int)(fractpart)); //Decimal part
}

static void smartDelay(unsigned long ms)
{
  unsigned long start = millis();
  do
  {
    while (ss.available())
      gps.encode(ss.read());
  } while (millis() - start < ms);
}


void OnSleep()
{
  Serial.printf("[lowp] lowpower mode  %d ms\r\n",timetowake);
  Serial.println("---------------------------zzzzzzzz----------------------------");
  turnOffRGB();
  lowpower = 1;
  TimerSetValue( &wakeup, timetowake );
  TimerStart( &wakeup );
}

void GPSWakeUp()
{
  if (gpslowpower > 0)
  {
    Serial.println("Waking up GPS");
    //ss.flush();
    ss.println();
    gps = TinyGPSPlus();
    gpslowpower = 0;
  }
}

void GPSStandBy()
{
  if (gpslowpower < 1)
  {
    Serial.println("Putting GPS in Low Power");
    ss.write(GPSStandby,sizeof(GPSStandby));
    //ss.flush();
    //ss.read();
    //ss = softSerial(grx, gtx);
    //ss.begin(9600);
    gpslowpower = 1;
  }
}

void OnWakeup()
{
  lowpower = 0;
  Serial.printf("[wkup] wake up, %d ms later into lowpower mode.\r\n",timetosleep);
  GPSWakeUp();
  uint32_t currentTime=TimerGetCurrentTime()/1000;
  uint16_t voltage = getBatteryVoltage();
  Serial.println(voltage);
  Serial.printf("[time] upTime: %d sec. \r\n",currentTime);
  txNumber=0;
   while (!gps.location.isValid()) //while data is available
   {
    Serial.println("waiting for GPS");
    Serial.println(gps.satellites.value());
    Serial.println(gps.charsProcessed());
    Serial.println(txNumber);
    txNumber += 1;
    if (txNumber == 180)
    {
      Serial.println("Resetting GPS Object...");
      gps = TinyGPSPlus();
      //ss.read();
      //ss.write(reset_gps,sizeof(reset_gps));
    }
    if (txNumber >= 200)
    {
       Serial.println("Resetting GPS Module...");
       ss.write(reset_gps,sizeof(reset_gps));
       gps = TinyGPSPlus();
       //ss.read();
      txNumber = 0;
    }
    smartDelay(1000);
   }
   if (gps.location.isValid()) //check whether gps location is valid
      {
        char c_lat[10];
        char c_lng[10];
        dtostrf(gps.location.lat(),8,6,c_lat); //the gps sends the latitude as a double, I convert it to a char here for the radio
        dtostrf(gps.location.lng(),8,6,c_lng);
        sprintf(txpacket,"%s,%s", c_lat, c_lng);  //start a package

        turnOnRGB(COLOR_RECEIVED,0); //change rgb color

        Serial.printf("\r\nsending packet \"%s\" , length %d\r\n",txpacket, strlen(txpacket)); //more debugging

        Radio.Send( (uint8_t *)txpacket, strlen(txpacket) ); //send the package out
        GPSStandBy();
        Radio.Sleep();
        TimerSetValue( &sleep, timetosleep );
        TimerStart( &sleep );
      }
}