#include "sx1276.h"

// LoRa registers
#define REG_LR_FIFOADDRPTR                          0x0d
#define REG_LR_FIFOTXBASEADDR                       0x0e
#define REG_LR_FIFORXBASEADDR                       0x0f
#define REG_LR_FIFORXCURRENTADDR /*REG_LR_RXDATAADDR*/  0x10
#define REG_LR_IRQFLAGSMASK                         0x11
#define REG_LR_IRQFLAGS                             0x12
#define REG_LR_RXNBBYTES                            0x13
#define REG_LR_RXHEADERCNTVALUE_MSB                 0x14
#define REG_LR_RXHEADERCNTVALUE_LSB                 0x15
#define REG_LR_RXPACKETCNTVALUE_MSB                 0x16
#define REG_LR_RXPACKETCNTVALUE_LSB                 0x17
#define REG_LR_MODEMSTAT                            0x18
#define REG_LR_PKTSNRVALUE                          0x19
#define REG_LR_PKTRSSIVALUE                         0x1a
#define REG_LR_RSSIVALUE                            0x1b
#define REG_LR_HOPCHANNEL                           0x1c
#define REG_LR_MODEMCONFIG                          0x1d
#define REG_LR_MODEMCONFIG2                         0x1e
#define REG_LR_SYMBTIMEOUTLSB                       0x1f
#define REG_LR_PREAMBLEMSB                          0x20
#define REG_LR_PREAMBLELSB                          0x21
#define REG_LR_PAYLOADLENGTH                        0x22 // and RX length for implicit
#define REG_LR_RX_MAX_PAYLOADLENGTH                 0x23 // length limit for explicit mode
#define REG_LR_HOPPERIOD                            0x24
#define REG_LR_RXBYTEADDR /*REG_LR_RXDATAADDR*/     0x25
#define REG_LR_MODEMCONFIG3                         0x26   
#define REG_LR_PPM_CORRECTION_LSB                   0x27
#define REG_LR_TEST28                               0x28  // est_freq_error
#define REG_LR_TEST29                               0x29    // est_freq_error
#define REG_LR_TEST2A                               0x2a    // est_freq_error
#define REG_LR_TEST2B                               0x2b    // 
#define REG_LR_WIDEBAND_RSSI                        0x2c 
#define REG_LR_AGCH_TH                              0x2d    // agc_upper_th
#define REG_LR_AGCL_TH                              0x2e    // agc_lower_th
#define REG_LR_IFFRQH                               0x2f    // if_freq(12:8)
#define REG_LR_IFFRQL                               0x30    // if_freq(7:0)
#define REG_LR_TEST31                               0x31    // if_freq_auto, ...
#define REG_LR_TEST32                               0x32    // 
#define REG_LR_TEST33                               0x33
#define REG_LR_DETECTION_THRESHOLD                  0x37

typedef union {
    struct {    // sx1276 register 0x12
        uint8_t CadDetected         : 1;    // 0
        uint8_t FhssChangeChannel   : 1;    // 1
        uint8_t CadDone             : 1;    // 2
        uint8_t TxDone              : 1;    // 3
        uint8_t ValidHeader         : 1;    // 4
        uint8_t PayloadCrcError     : 1;    // 5
        uint8_t RxDone              : 1;    // 6
        uint8_t RxTimeout           : 1;    // 7
    } bits;
    uint8_t octet;
} RegIrqFlags_t;

typedef union {
    struct {    // sx1276 register 0x18
        uint8_t detect          : 1;    // 0
        uint8_t sync            : 1;    // 1
        uint8_t rx_ongoing      : 1;    // 2
        uint8_t header_valid    : 1;    // 3
        uint8_t clear           : 1;    // 4
        uint8_t RxCodingRate    : 3;    // 5,6,7
    } bits;
    uint8_t octet;
} RegModemStatus_t;

typedef union {
    struct {    // sx1276 register 0x1c
        uint8_t FhssPresentChannel  : 6;    // 0,1,2,3,4,5
        uint8_t RxPayloadCrcOn      : 1;    // 6
        uint8_t PllTimeout          : 1;    // 7
    } bits;
    uint8_t octet;
} RegHopChannel_t;

typedef union {
    struct {    // sx1276 register 0x1d
        uint8_t ImplicitHeaderModeOn    : 1;    // 0
        uint8_t CodingRate              : 3;    // 1,2,3
        uint8_t Bw                      : 4;    // 4,5,6,7
    } sx1276bits;
    uint8_t octet;
} RegModemConfig_t;

typedef union {
    struct {    // sx1276 register 0x1e
        uint8_t SymbTimeoutMsb          : 2;    // 0,1
        uint8_t RxPayloadCrcOn          : 1;    // 2
        uint8_t TxContinuousMode        : 1;    // 3
        uint8_t SpreadingFactor         : 4;    // 4,5,6,7
    } sx1276bits;
    uint8_t octet;
} RegModemConfig2_t;

typedef union {
    struct {    // sx1276 register 0x26
        uint8_t reserved    : 2;    // 0,1
        uint8_t AgcAutoOn   : 1;    // 2
        uint8_t LowDataRateOptimize  : 1;    // 3   ppm_offset
        uint8_t unused      : 4;    // 4,5,6,7 
    } sx1276bits;
    uint8_t octet;
} RegModemConfig3_t;


typedef union {
    struct {    // sx1276 register 0x31
        uint8_t detect_trig_same_peaks_nb  : 3;    // 0,1,2
        uint8_t disable_pll_timeout        : 1;    // 3
        uint8_t tracking_intergral         : 2;    // 4,5
        uint8_t frame_sync_gain            : 1;    // 6
        uint8_t if_freq_auto               : 1;    // 7
    } bits;
    uint8_t octet;
} RegTest31_t;

//class SX1276_lora : public SX1276
class SX1276_lora {
    public:
        //SX1276_lora(PinName mosi, PinName miso, PinName sclk, PinName cs, PinName rst, PinName dio_0, PinName dio_1, PinName fem_ctx, PinName fem_cps);
        SX1276_lora(SX1276& r);
        
        ~SX1276_lora();
        
        /** changes from FSK mode to LoRa mdoe */
        void enable(void);
        
        /** fills radio FIFO with payload contents, prior to transmission
         * @param len count of bytes to put into FIFO
         * @note tx_buf[] should contain desired payload (to send) prior to calling
         */
        void write_fifo(uint8_t len);     
        
        /** transmit a packet
         * @param len size of packet
         * @note Limited to (lora fifo size 256)
         */
        void start_tx(uint8_t len);
        
        /** start receive mode
         * @note the variable service_action needs to be monitored to indicate read_fifo() needs to be called to pull packet from FIFO.
         */
        void start_rx(void);
        
        /** Called by main program when indicated by service_action variable, to pull recevied packet from radio FIFO.
         * @returns count of bytes received
         * @note received packet in rx_buf[]
         */
        void read_fifo(uint8_t len);
        
        /** CodingRate: how much FEC to encoding onto packet */
        uint8_t getCodingRate(bool from_rx);    // false:transmitted, true:last recevied packet
        void setCodingRate(uint8_t cr);
        
        /** HeaderMode: explicit mode sents CodingRate and payload length, implicit mode requires assumption by receiver */
        bool getHeaderMode(void);
        void setHeaderMode(bool hm);

        uint8_t getBw(void);
        void setBw(uint8_t bw);
        
        /** spreading factor: trade-off between data rate and processing gain (link budget) */
        uint8_t getSf(void);
        void setSf(uint8_t sf);        
        
        /** enable CRC in transmitted packet */
        bool getRxPayloadCrcOn(void);
        void setRxPayloadCrcOn(bool);
        
        bool getAgcAutoOn(void);
        void setAgcAutoOn(bool);
        
        float get_pkt_rssi(void);
        
        service_action_e service(void); // (SLIH) ISR bottom half 
        
        bool poll_vh;
        
        RegIrqFlags_t       RegIrqFlags;            // 0x12
        uint8_t             RegRxNbBytes;           // 0x13
        RegModemStatus_t    RegModemStatus;         // 0x18
        int8_t              RegPktSnrValue;         // 0x19  signed, s/n can be negative
        uint8_t             RegPktRssiValue;        // 0x1a
        RegHopChannel_t     RegHopChannel;          // 0x1c
        RegModemConfig_t    RegModemConfig;         // 0x1d
        RegModemConfig2_t   RegModemConfig2;        // 0x1e
        uint16_t            RegPreamble;            // 0x20->0x21
        uint8_t             RegPayloadLength;       // 0x22
        uint8_t             RegRxMaxPayloadLength;  // 0x23
        uint8_t             RegHopPeriod;           // 0x24
        RegModemConfig3_t   RegModemConfig3;        // 0x26
        RegTest31_t         RegTest31;              // 0x31
        
    private:
        SX1276& m_xcvr;
        void set_nb_trig_peaks(int);                                                         
};
