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

// This EUI must be in little-endian format, so least-significant-byte
// first. When copying an EUI from ttnctl output, this means to reverse
// the bytes. For TTN issued EUIs the last bytes should be 0xD5, 0xB3,
// 0x70.
static const u1_t PROGMEM APPEUI[8]={FILL_ME_IN};
void os_getArtEui (u1_t* buf) { memcpy_P(buf, APPEUI, 8);}

// This should also be in little endian format, see above.
static const u1_t PROGMEM DEVEUI[8]={FILL_ME_IN};
void os_getDevEui (u1_t* buf) { memcpy_P(buf, DEVEUI, 8);}

// This key should be in big endian format (or, since it is not really a
// number but a block of memory, endianness does not really apply). In
// practice, a key taken from ttnctl can be copied as-is.
// The key shown here is the semtech default key.
static const u1_t PROGMEM APPKEY[16] = {FILL_ME_IN};
void os_getDevKey (u1_t* buf) {  memcpy_P(buf, APPKEY, 16);}

static uint8_t mydata[] = "Hello, world!";
static osjob_t sendjob;

// Schedule TX every this many seconds (might become longer due to duty
// cycle limitations).
const unsigned TX_INTERVAL = 5;

//Sparkfun Pro RF
const lmic_pinmap lmic_pins = {
    .nss = 12,//RFM Chip Select
    .rxtx = LMIC_UNUSED_PIN,
    .rst = 7,//RFM Reset
    .dio = {6, 10, 11}, //RFM Interrupt, RFM LoRa pin, RFM LoRa pin
};

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

            // Disable link check validation (automatically enabled
            // during join, but not supported by TTN at this time).
            LMIC_setLinkCheckMode(0);
            break;
        case EV_RFU1:
            SerialUSB.println(F("EV_RFU1"));
            break;
        case EV_JOIN_FAILED:
            SerialUSB.println(F("EV_JOIN_FAILED"));
            break;
        case EV_REJOIN_FAILED:
            SerialUSB.println(F("EV_REJOIN_FAILED"));
            break;
            break;
        case EV_TXCOMPLETE:
            SerialUSB.println(F("EV_TXCOMPLETE (includes waiting for RX windows)"));
            if (LMIC.txrxFlags & TXRX_ACK)
              SerialUSB.println(F("Received ack"));
            if (LMIC.dataLen) {
              SerialUSB.println(F("Received "));
              SerialUSB.println(LMIC.dataLen);
              SerialUSB.println(F(" bytes of payload"));
            }
            // Schedule next transmission
            os_setTimedCallback(&sendjob, os_getTime()+sec2osticks(TX_INTERVAL), do_send);
            break;
        case EV_LOST_TSYNC:
            SerialUSB.println(F("EV_LOST_TSYNC"));
            break;
        case EV_RESET:
            SerialUSB.println(F("EV_RESET"));
            break;
        case EV_RXCOMPLETE:
            // data received in ping slot
            SerialUSB.println(F("EV_RXCOMPLETE"));
            break;
        case EV_LINK_DEAD:
            SerialUSB.println(F("EV_LINK_DEAD"));
            break;
        case EV_LINK_ALIVE:
            SerialUSB.println(F("EV_LINK_ALIVE"));
            break;
         default:
            SerialUSB.println(F("Unknown event"));
            break;
    }
}

void do_send(osjob_t* j){
    // Check if there is not a current TX/RX job running
    if (LMIC.opmode & OP_TXRXPEND) {
        SerialUSB.println(F("OP_TXRXPEND, not sending"));
    } else {
        // Prepare upstream data transmission at the next possible time.
        LMIC_setTxData2(1, mydata, sizeof(mydata)-1, 0);
        SerialUSB.println(F("Packet queued"));
    }
    // Next TX is scheduled after TX_COMPLETE event.
}

void setup() {
    SerialUSB.begin(9600);
    while(!SerialUSB); 
    SerialUSB.println(F("Starting"));

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

    // allow much more clock error than the X/1000 default. See:
    // https://github.com/mcci-catena/arduino-lorawan/issues/74#issuecomment-462171974
    // https://github.com/mcci-catena/arduino-lmic/commit/42da75b56#diff-16d75524a9920f5d043fe731a27cf85aL633
    // the X/1000 means an error rate of 0.1%; the above issue discusses using
    // values up to 10%. so, values from 10 (10% error, the most lax) to 1000
    // (0.1% error, the most strict) can be used.
    LMIC_setClockError(1 * MAX_CLOCK_ERROR / 40);

    // Sub-band 2 - Helium Network
    LMIC_selectSubBand(1); // zero indexed 
    LMIC_setLinkCheckMode(0);
    LMIC_setDrTxpow(DR_SF7, 14);

    // Start job (sending automatically starts OTAA too)
    do_send(&sendjob);
}

void loop() {
    os_runloop_once();
}