/*
 * This file contains a copy of the master content sx1276PingPong
 * with adaption for the SX1276Generic environment
 * (c) 2017 Helmut Tschemernjak
 * 30826 Garbsen (Hannover) Germany
 */
 
#include "mbed.h"
#include "PinMap.h"
#include "GenericPingPong.h"
#include "sx1276-mbed-hal.h"
#include "main.h"

#ifdef FEATURE_LORA

/* Set this flag to '1' to display debug messages on the console */
#define DEBUG_MESSAGE   1

/* Set this flag to '1' to use the LoRa modulation or to '0' to use FSK modulation */
#define USE_MODEM_LORA  1
#define USE_MODEM_FSK   !USE_MODEM_LORA
#define RF_FREQUENCY            RF_FREQUENCY_868_1  // Hz
#define TX_OUTPUT_POWER         14                  // 14 dBm

#if USE_MODEM_LORA == 1

#define LORA_BANDWIDTH          125000  // LoRa default, details in SX1276::BandwidthMap
#define LORA_SPREADING_FACTOR   LORA_SF7
#define LORA_CODINGRATE         LORA_ERROR_CODING_RATE_4_5

#define LORA_PREAMBLE_LENGTH    8       // Same for Tx and Rx
#define LORA_SYMBOL_TIMEOUT     5       // Symbols
#define LORA_FIX_LENGTH_PAYLOAD_ON  false
#define LORA_FHSS_ENABLED       false  
#define LORA_NB_SYMB_HOP        4     
#define LORA_IQ_INVERSION_ON    false
#define LORA_CRC_ENABLED        true
    
#elif USE_MODEM_FSK == 1

#define FSK_FDEV                25000     // Hz
#define FSK_DATARATE            19200     // bps
#define FSK_BANDWIDTH           50000     // Hz
#define FSK_AFC_BANDWIDTH       83333     // Hz
#define FSK_PREAMBLE_LENGTH     5         // Same for Tx and Rx
#define FSK_FIX_LENGTH_PAYLOAD_ON   false
#define FSK_CRC_ENABLED         true
    
#else
    #error "Please define a modem in the compiler options."
#endif 


#define RX_TIMEOUT_VALUE    3500	// in ms

//#define BUFFER_SIZE       32        // Define the payload size here
#define BUFFER_SIZE         64        // Define the payload size here

/*
 *  Global variables declarations
 */
typedef enum
{
    LOWPOWER = 0,
    IDLE,
    
    RX,
    RX_TIMEOUT,
    RX_ERROR,
    
    TX,
    TX_TIMEOUT,
    
    CAD,
    CAD_DONE
} AppStates_t;

volatile AppStates_t State = LOWPOWER;

/*!
 * Radio events function pointer
 */
static RadioEvents_t RadioEvents;

/*
 *  Global variables declarations
 */
SX1276Generic *Radio;


const uint8_t PingMsg[] = { 0xff, 0xff, 0x00, 0x00, 'P', 'I', 'N', 'G'};// "PING";
const uint8_t PongMsg[] = { 0xff, 0xff, 0x00, 0x00, 'P', 'O', 'N', 'G'};// "PONG";

uint16_t BufferSize = BUFFER_SIZE;
uint8_t *Buffer;

DigitalOut *led3;


int SX1276PingPong() 
{
#if( defined ( TARGET_KL25Z ) || defined ( TARGET_LPC11U6X ) )
    DigitalOut *led = new DigitalOut(LED2);
#elif defined(TARGET_NUCLEO_L073RZ) || defined(TARGET_DISCO_L072CZ_LRWAN1)
    DigitalOut *led = new DigitalOut(LED4);   // RX red
    led3 = new DigitalOut(LED3);  // TX blue
#else
    DigitalOut *led = new DigitalOut(LED1);
    led3 = led;
#endif
    
    Buffer = new  uint8_t[BUFFER_SIZE];
    *led3 = 1;

#ifdef B_L072Z_LRWAN1_LORA
    Radio = new SX1276Generic(NULL, MURATA_SX1276,
    		LORA_SPI_MOSI, LORA_SPI_MISO, LORA_SPI_SCLK, LORA_CS, LORA_RESET,
        	LORA_DIO0, LORA_DIO1, LORA_DIO2, LORA_DIO3, LORA_DIO4, LORA_DIO5,
        	LORA_ANT_RX, LORA_ANT_TX, LORA_ANT_BOOST, LORA_TCXO);
#else // RFM95
    Radio = new SX1276Generic(NULL, RFM95_SX1276,
			LORA_SPI_MOSI, LORA_SPI_MISO, LORA_SPI_SCLK, LORA_CS, LORA_RESET,
            LORA_DIO0, LORA_DIO1, LORA_DIO2, LORA_DIO3, LORA_DIO4, LORA_DIO5);

#endif
    
    uint8_t i;
    bool isMaster = true;
    
    dprintf("SX1276 Ping Pong Demo Application" );
    dprintf("Freqency: %.1f", (double)RF_FREQUENCY/1000000.0);
    dprintf("TXPower: %d dBm",  TX_OUTPUT_POWER);
#if USE_MODEM_LORA == 1
    dprintf("Bandwidth: %d Hz", LORA_BANDWIDTH);
    dprintf("Spreading factor: SF%d", LORA_SPREADING_FACTOR);
#elif USE_MODEM_FSK == 1
    dprintf("Bandwidth: %d kHz",  FSK_BANDWIDTH);
    dprintf("Baudrate: %d", FSK_DATARATE);
#endif
    // Initialize Radio driver
    RadioEvents.TxDone = OnTxDone;
    RadioEvents.RxDone = OnRxDone;
    RadioEvents.RxError = OnRxError;
    RadioEvents.TxTimeout = OnTxTimeout;
    RadioEvents.RxTimeout = OnRxTimeout;    
    if (Radio->Init( &RadioEvents ) == false) {
        while(1) {
        	dprintf("Radio could not be detected!");
        	wait( 1 );
        }
    }

    
    switch(Radio->DetectBoardType()) {
        case SX1276MB1LAS:
            if (DEBUG_MESSAGE)
                dprintf(" > Board Type: SX1276MB1LAS <");
            break;
        case SX1276MB1MAS:
            if (DEBUG_MESSAGE)
                dprintf(" > Board Type: SX1276MB1LAS <");
        case MURATA_SX1276:
            if (DEBUG_MESSAGE)
            	dprintf(" > Board Type: MURATA_SX1276_STM32L0 <");
            break;
        case RFM95_SX1276:
            if (DEBUG_MESSAGE)
                dprintf(" > HopeRF RFM95xx <");
            break;
        default:
            dprintf(" > Board Type: unknown <");
    }

    Radio->SetChannel(RF_FREQUENCY ); 

#if USE_MODEM_LORA == 1
    
    if (LORA_FHSS_ENABLED)
        dprintf("             > LORA FHSS Mode <");
    if (!LORA_FHSS_ENABLED)
        dprintf("             > LORA Mode <");

    Radio->SetTxConfig( MODEM_LORA, TX_OUTPUT_POWER, 0, LORA_BANDWIDTH,
                         LORA_SPREADING_FACTOR, LORA_CODINGRATE,
                         LORA_PREAMBLE_LENGTH, LORA_FIX_LENGTH_PAYLOAD_ON,
                         LORA_CRC_ENABLED, LORA_FHSS_ENABLED, LORA_NB_SYMB_HOP, 
                         LORA_IQ_INVERSION_ON, 2000 );
    
    Radio->SetRxConfig( MODEM_LORA, LORA_BANDWIDTH, LORA_SPREADING_FACTOR,
                         LORA_CODINGRATE, 0, LORA_PREAMBLE_LENGTH,
                         LORA_SYMBOL_TIMEOUT, LORA_FIX_LENGTH_PAYLOAD_ON, 0,
                         LORA_CRC_ENABLED, LORA_FHSS_ENABLED, LORA_NB_SYMB_HOP, 
                         LORA_IQ_INVERSION_ON, true );
                         
#elif USE_MODEM_FSK == 1

    dprintf("              > FSK Mode <");
    Radio->SetTxConfig( MODEM_FSK, TX_OUTPUT_POWER, FSK_FDEV, 0,
                         FSK_DATARATE, 0,
                         FSK_PREAMBLE_LENGTH, FSK_FIX_LENGTH_PAYLOAD_ON,
                         FSK_CRC_ENABLED, 0, 0, 0, 2000 );
    
    Radio->SetRxConfig( MODEM_FSK, FSK_BANDWIDTH, FSK_DATARATE,
                         0, FSK_AFC_BANDWIDTH, FSK_PREAMBLE_LENGTH,
                         0, FSK_FIX_LENGTH_PAYLOAD_ON, 0, FSK_CRC_ENABLED,
                         0, 0, false, true );
                         
#else

#error "Please define a modem in the compiler options."

#endif
     
    if (DEBUG_MESSAGE)
        dprintf("Starting Ping-Pong loop"); 

        
    Radio->Rx( RX_TIMEOUT_VALUE );
    
    while( 1 )
    {
#ifdef TARGET_STM32L4
        WatchDogUpdate();
#endif
        
        switch( State )
        {
        case RX:
        	*led3 = 0;
            if( isMaster == true )
            {
                if( BufferSize > 0 )
                {
                    if( memcmp(Buffer, PongMsg, sizeof(PongMsg)) == 0 )
                    {
                        *led = !*led;
                        dprintf( "...Pong" );
                        // Send the next PING frame            
                        memcpy(Buffer, PingMsg, sizeof(PingMsg));
                        // We fill the buffer with numbers for the payload 
                        for( i = sizeof(PingMsg); i < BufferSize; i++ )
                        {
                            Buffer[i] = i - sizeof(PingMsg);
                        }
                        wait_ms( 10 ); 
                        Radio->Send( Buffer, BufferSize );
                    }
                    else if( memcmp(Buffer, PingMsg, sizeof(PingMsg)) == 0 )
                    { // A master already exists then become a slave
                        dprintf( "...Ping" );
                        *led = !*led;
                        isMaster = false;
                        // Send the next PONG frame
                        memcpy(Buffer, PongMsg, sizeof(PongMsg));        
                        // We fill the buffer with numbers for the payload 
                        for( i = sizeof(PongMsg); i < BufferSize; i++ )
                        {
                            Buffer[i] = i - sizeof(PongMsg);
                        }
                        wait_ms( 10 ); 
                        Radio->Send( Buffer, BufferSize );
                    }
                    else // valid reception but neither a PING or a PONG message
                    {    // Set device as master ans start again
                        isMaster = true;
                        Radio->Rx( RX_TIMEOUT_VALUE );
                    }    
                }
            }
            else
            {
                if( BufferSize > 0 )
                {
                    if( memcmp(Buffer, PingMsg, sizeof(PingMsg)) == 0 )
                    {
                        *led = !*led;
                        dprintf( "...Ping" );
                        // Send the reply to the PING string
                        memcpy(Buffer, PongMsg, sizeof(PongMsg));
                        // We fill the buffer with numbers for the payload 
                        for( i = sizeof(PongMsg); i < BufferSize; i++ )
                        {
                            Buffer[i] = i - sizeof(PongMsg);
                        }
                        wait_ms( 10 );  
                        Radio->Send( Buffer, BufferSize );
                    }
                    else // valid reception but not a PING as expected
                    {    // Set device as master and start again
                        isMaster = true;
                        Radio->Rx( RX_TIMEOUT_VALUE );
                    }    
                }
            }
            State = LOWPOWER;
            break;
        case TX:    
            *led3 = 1;
            if( isMaster == true )  
            {
                dprintf("Ping..." );
            }
            else
            {
                dprintf("Pong..." );
            }
            Radio->Rx( RX_TIMEOUT_VALUE );
            State = LOWPOWER;
            break;
        case RX_TIMEOUT:
            if( isMaster == true )
            {
                // Send the next PING frame
                memcpy(Buffer, PingMsg, sizeof(PingMsg));
                for( i = sizeof(PingMsg); i < BufferSize; i++ )
                {
                    Buffer[i] = i - sizeof(PingMsg);
                }
                wait_ms( 10 ); 
                Radio->Send( Buffer, BufferSize );
            }
            else
            {
                Radio->Rx( RX_TIMEOUT_VALUE );  
            }             
            State = LOWPOWER;
            break;
        case RX_ERROR:
            // We have received a Packet with a CRC error, send reply as if packet was correct
            if( isMaster == true )
            {
                // Send the next PING frame
                memcpy(Buffer, PingMsg, sizeof(PingMsg));
                for( i = 4; i < BufferSize; i++ )
                {
                    Buffer[i] = i - 4;
                }
                wait_ms( 10 );  
                Radio->Send( Buffer, BufferSize );
            }
            else
            {
                // Send the next PONG frame
                memcpy(Buffer, PongMsg, sizeof(PongMsg));
                for( i = sizeof(PongMsg); i < BufferSize; i++ )
                {
                    Buffer[i] = i - sizeof(PongMsg);
                }
                wait_ms( 10 );  
                Radio->Send( Buffer, BufferSize );
            }
            State = LOWPOWER;
            break;
        case TX_TIMEOUT:
            Radio->Rx( RX_TIMEOUT_VALUE );
            State = LOWPOWER;
            break;
        case LOWPOWER:
        	sleep();
            break;
        default:
            State = LOWPOWER;
            break;
        }    
    }
}

void OnTxDone(void *radio, void *userThisPtr, void *userData)
{
    Radio->Sleep( );
    State = TX;
    if (DEBUG_MESSAGE)
        dprintf("> OnTxDone");
}

void OnRxDone(void *radio, void *userThisPtr, void *userData, uint8_t *payload, uint16_t size, int16_t rssi, int8_t snr)
{
    Radio->Sleep( );
    BufferSize = size;
    memcpy( Buffer, payload, BufferSize );
    State = RX;
    if (DEBUG_MESSAGE)
        dprintf("> OnRxDone: RssiValue=%d dBm, SnrValue=%d", rssi, snr);
    dump("Data:", payload, size);
}

void OnTxTimeout(void *radio, void *userThisPtr, void *userData)
{
    *led3 = 0;
    Radio->Sleep( );
    State = TX_TIMEOUT;
    if(DEBUG_MESSAGE)
        dprintf("> OnTxTimeout");
}

void OnRxTimeout(void *radio, void *userThisPtr, void *userData)
{
    *led3 = 0;
    Radio->Sleep( );
    Buffer[BufferSize-1] = 0;
    State = RX_TIMEOUT;
    if (DEBUG_MESSAGE)
        dprintf("> OnRxTimeout");
}

void OnRxError(void *radio, void *userThisPtr, void *userData)
{
    Radio->Sleep( );
    State = RX_ERROR;
    if (DEBUG_MESSAGE)
        dprintf("> OnRxError");
}

#endif
