#include <lmic.h>
#include <hal/hal.h>
#include <SPI.h>


#define CFG_eu868

// LoRaWAN NwkSKey, network session key
// This is the default Semtech key, which is used by the early prototype TTN
// network.

#ifdef CREDENTIALS
static const PROGMEM u1_t NWKSKEY[16] = NWKSKEY1;
static const PROGMEM u1_t APPSKEY[16] = APPSKEY1;
static const PROGMEM u4_t DEVADDR = DEVADDR1;
#else
static const PROGMEM u1_t NWKSKEY[16] = { my_network_key };
static const PROGMEM u1_t APPSKEY[16] = { my_app_key };
static const PROGMEM u4_t DEVADDR = my_dev_address;
#endif

unsigned long entry = millis();

#define GREENLED 3
#define REDLED 8
#define SFSWITCH 4
#define RUNPIN 5

// These callbacks are only used in over-the-air activation, so they are
// left empty here (we cannot leave them out completely unless
// DISABLE_JOIN is set in config.h, otherwise the linker will complain).
void os_getArtEui (u1_t* buf) { }
void os_getDevEui (u1_t* buf) { }
void os_getDevKey (u1_t* buf) { }

byte counter = 0;
static osjob_t sendjob;
bool switchState = true, oldSwitchState = false;

// Schedule TX every this many seconds (might become longer due to duty
// cycle limitations).
const unsigned TX_INTERVAL = 60;

// Pin mapping
const lmic_pinmap lmic_pins = {
  .nss = 10,
  .rxtx = LMIC_UNUSED_PIN,
  .rst = 9,
  .dio = {2, 6, 7},
};

void onEvent (ev_t ev) {
  Serial.print(os_getTime());
  Serial.print(": ");
  switch (ev) {
    case EV_SCAN_TIMEOUT:
      Serial.println(F("EV_SCAN_TIMEOUT"));
      break;
    case EV_BEACON_FOUND:
      Serial.println(F("EV_BEACON_FOUND"));
      break;
    case EV_BEACON_MISSED:
      Serial.println(F("EV_BEACON_MISSED"));
      break;
    case EV_BEACON_TRACKED:
      Serial.println(F("EV_BEACON_TRACKED"));
      break;
    case EV_JOINING:
      Serial.println(F("EV_JOINING"));
      break;
    case EV_JOINED:
      Serial.println(F("EV_JOINED"));
      break;
    case EV_RFU1:
      Serial.println(F("EV_RFU1"));
      break;
    case EV_JOIN_FAILED:
      Serial.println(F("EV_JOIN_FAILED"));
      break;
    case EV_REJOIN_FAILED:
      Serial.println(F("EV_REJOIN_FAILED"));
      break;

    case EV_TXCOMPLETE:
      Serial.println(F("EV_TXCOMPLETE (includes waiting for RX windows)"));
      Serial.println(LMIC.dataLen);
      if (LMIC.dataLen) {
        // data received in rx slot after tx
        uint8_t downlink[LMIC.dataLen];
        memcpy(&downlink, &(LMIC.frame + LMIC.dataBeg)[0], LMIC.dataLen);
        // Turn on/off fan if we get the magic number
        if ( downlink[0] == 0x31 ) {
          // digitalWrite(FanPin, HIGH);
        }
        else {
          // digitalWrite(FanPin, LOW);
        }

        Serial.print(F("Data Received: "));
        Serial.write(LMIC.frame + LMIC.dataBeg, LMIC.dataLen);
        Serial.println();

      }
      // Schedule next transmission
      os_setTimedCallback(&sendjob, os_getTime() + sec2osticks(TX_INTERVAL), do_send);
      digitalWrite(REDLED, HIGH);
      break;
    /*
      case EV_TXCOMPLETE:
      Serial.print((millis() - entry) / 1000);  Serial.print(" ");
      entry = millis();
      Serial.println(F("EV_TXCOMPLETE (includes waiting for RX windows)"));
      if (LMIC.txrxFlags & TXRX_ACK)
      Serial.println(F("Received ack"));
      if (LMIC.dataLen) {
      Serial.println(F("Received "));
      Serial.println(LMIC.dataLen);
      Serial.println(F(" bytes of payload"));
      }
      // Schedule next transmission
      os_setTimedCallback(&sendjob, os_getTime() + sec2osticks(TX_INTERVAL), do_send);
      digitalWrite(REDLED, HIGH);
      break;
    */
    case EV_LOST_TSYNC:
      Serial.println(F("EV_LOST_TSYNC"));
      break;
    case EV_RESET:
      Serial.println(F("EV_RESET"));
      break;
    case EV_RXCOMPLETE:
      // data received in ping slot
      Serial.println(F("EV_RXCOMPLETE"));
      break;
    case EV_LINK_DEAD:
      Serial.println(F("EV_LINK_DEAD"));
      break;
    case EV_LINK_ALIVE:
      Serial.println(F("EV_LINK_ALIVE"));
      break;
    default:
      Serial.println(F("Unknown event"));
      break;
  }
}

void do_send(osjob_t* j) {
  byte buffer[32];
  // Check if there is not a current TX/RX job running
  if (LMIC.opmode & OP_TXRXPEND) {
    Serial.println(F("OP_TXRXPEND, not sending"));
  } else {
    // Prepare upstream data transmission at the next possible time.
    String message = "Hello TTN from arduino uno!";
    message.getBytes(buffer, message.length() + 1);

    Serial.println("Sending: " + message);
    LMIC_setTxData2(1, (uint8_t*) buffer, message.length() , 0);
    Serial.println(F(" Packet queued"));
    digitalWrite(REDLED, LOW);
  }
  // Next TX is scheduled after TX_COMPLETE event.
}

void setup() {
  Serial.begin(9600);
  Serial.println(F("Starting"));

  pinMode(GREENLED, OUTPUT);
  pinMode(REDLED, OUTPUT);
  pinMode(SFSWITCH, INPUT_PULLUP);
  pinMode(RUNPIN, INPUT_PULLUP);
  digitalWrite(REDLED, HIGH);
  digitalWrite(GREENLED, HIGH);

#ifdef VCC_ENABLE
  // For Pinoccio Scout boards
  pinMode(VCC_ENABLE, OUTPUT);
  digitalWrite(VCC_ENABLE, HIGH);
  delay(1000);
#endif

  // LMIC init
  os_init();
  // Reset the MAC state. Session and pending data transfers will be discarded.
  LMIC_reset();

  // Set static session parameters. Instead of dynamically establishing a session
  // by joining the network, precomputed session parameters are be provided.
#ifdef PROGMEM
  // On AVR, these values are stored in flash and only copied to RAM
  // once. Copy them to a temporary buffer here, LMIC_setSession will
  // copy them into a buffer of its own again.
  uint8_t appskey[sizeof(APPSKEY)];
  uint8_t nwkskey[sizeof(NWKSKEY)];
  memcpy_P(appskey, APPSKEY, sizeof(APPSKEY));
  memcpy_P(nwkskey, NWKSKEY, sizeof(NWKSKEY));
  LMIC_setSession (0x1, DEVADDR, nwkskey, appskey);
#else
  // If not running an AVR with PROGMEM, just use the arrays directly
  LMIC_setSession (0x1, DEVADDR, NWKSKEY, APPSKEY);
#endif

#if defined(CFG_eu868)
  Serial.println("European Channels");
  for (int i = 1; i <= 8; i++) LMIC_disableChannel(i);
#elif defined(CFG_us915)
  // NA-US channels 0-71 are configured automatically
  // but only one group of 8 should (a subband) should be active
  // TTN recommends the second sub band, 1 in a zero based count.
  // https://github.com/TheThingsNetwork/gateway-conf/blob/master/US-global_conf.json
  LMIC_selectSubBand(1);
#endif

  // Disable link check validation
  LMIC_setLinkCheckMode(0);

  // TTN uses SF9 for its RX2 window.
  LMIC.dn2Dr = DR_SF9;

  // Set data rate and transmit power for uplink (note: txpow seems to be ignored by the library)
  if (digitalRead(SFSWITCH) == HIGH) {
    Serial.println("SF7");
    LMIC_setDrTxpow(DR_SF7, 14);
  }
  else  {
    Serial.println("SF12");
    LMIC_setDrTxpow(DR_SF12, 14);
  }

  // Start job
  do_send(&sendjob);
}

void loop() {
  while (digitalRead(RUNPIN) == HIGH) {
    digitalWrite(GREENLED, HIGH);
    delay(10);
  }
  switchState = digitalRead(SFSWITCH);
  if (switchState != oldSwitchState) {
    delay(100);
    // Set data rate and transmit power for uplink (note: txpow seems to be ignored by the library)
    if (digitalRead(SFSWITCH) == HIGH) {
      Serial.println("SF7");
      LMIC_setDrTxpow(DR_SF7, 14);
    }
    else  {
      Serial.println("SF12");
      LMIC_setDrTxpow(DR_SF12, 14);
    }
    oldSwitchState = switchState;
  }
  digitalWrite(GREENLED, LOW);
  os_runloop_once();

}