#include <stdint.h>
#include <string.h>
#include "funk/openbeacon.h"
#include "funk/nrf24l01p.h"
#include "basic/byteorder.h"
#include "sysdefs.h"
#include "filesystem/ff.h"
#include "basic/uuid.h"
#include "basic/config.h"
#include "basic/random.h"

#include "SECRETS"

#define SAVE_OPENBEACON 1
const uint8_t mac[5] = {1,2,3,2,1};

volatile uint32_t oid = 0;
volatile uint32_t seq = 0;
volatile uint8_t strength = 0;

#if SAVE_OPENBEACON
static void openbeaconSave(uint32_t s);
#endif

static struct NRF_CFG oldconfig;

#if SAVE_OPENBEACON
static void openbeaconShutdown(void)
{    
    openbeaconSave(seq);
}

static void openbeaconSaveBlock(void)
{

    openbeaconSave(seq + OPENBEACON_SAVE + 1);
}

static void openbeaconSave(uint32_t s)
{
    FIL file;
    BYTE buf[4];
    UINT readbytes;

    if( f_open(&file, "beacon.cfg", FA_OPEN_ALWAYS|FA_WRITE) )
        return;

    uint32touint8p(s, buf);

    if( f_write(&file, buf, 4, &readbytes) )
        return; 

    f_close(&file);
}

static void openbeaconRead()
{
    FIL file;
    BYTE buf[4];
    UINT readbytes;

    if( f_open(&file, "beacon.cfg", FA_OPEN_EXISTING|FA_READ) )
        return;

    if( f_read(&file, buf, 4, &readbytes) )
        return;
    seq = uint8ptouint32(buf);
    
    f_close(&file);
}
#endif

void openbeaconSetup(void)
{
    oid = GetUUID32();
    strength = 0;
#if SAVE_OPENBEACON
    openbeaconRead();
    openbeaconSaveBlock();
#endif
}

static void openbeaconSendPacket(uint32_t id, uint32_t seq,
        uint8_t flags, uint8_t strength)
{
    uint8_t buf[16];
    uint8_t proto = 0x17;   //Tracking

    volatile uint16_t i;
    i = (getRandom()&0xfff)+1;
    while(i--);

    static uint32_t n = 123;
    if( --n == 0 ){
        n = 123;
        proto = 0x23;       //Nick name
    }

    buf[0]=0x10; // Length: 16 bytes
    buf[1]=proto;
    if( proto == 0x17 ){
        buf[2]=flags;
        buf[3]=strength*85; // Send intensity

        uint32touint8p(seq, buf+4);
        uint32touint8p(id, buf+8);

        buf[12]=0xff; // salt (0xffff always?)
        buf[13]=0xff;
#if ENCRYPT_OPENBEACON
        nrf_snd_pkt_crc_encr(16,buf,openbeaconkey);
#else
        nrf_snd_pkt_crc_encr(16,buf,NULL);
#endif
    }else{
        if( strlen(GLOBAL(nickname)) > 8 )
            buf[1] = 0x24;
        nrf_set_strength(3);
        uint32touint8p(id, buf+2);
        memcpy(buf+6, GLOBAL(nickname), 8);
#if ENCRYPT_OPENBEACON
        nrf_snd_pkt_crc_encr(16,buf,openbeaconkey);
#else
        nrf_snd_pkt_crc_encr(16,buf,NULL);
#endif
        if( strlen(GLOBAL(nickname)) < 9 )
            return;
        buf[1]=0x25;
        memcpy(buf+6, GLOBAL(nickname)+8, 8);
#if ENCRYPT_OPENBEACON
        nrf_snd_pkt_crc_encr(16,buf,openbeaconkey);
#else
        nrf_snd_pkt_crc_encr(16,buf,NULL);
#endif
    }   
}

void openbeaconSend(void)
{
    nrf_config_get(&oldconfig);

    nrf_set_channel(OPENBEACON_CHANNEL);
    nrf_set_strength(strength);
    nrf_set_tx_mac(sizeof(mac), mac);

    openbeaconSendPacket(oid, seq++, 0xFF, strength++);
    if( strength == 4 )
        strength = 0;
#if SAVE_OPENBEACON
    if( (seq & OPENBEACON_SAVE) == OPENBEACON_SAVE )
        openbeaconSaveBlock();
#endif
    nrf_config_set(&oldconfig);
    nrf_set_strength(3);
}