/*-----------------------------------------------------------------------*/
/* Low level disk I/O module SKELETON for FatFs     (C)ChaN, 2019        */
/*-----------------------------------------------------------------------*/
/* If a working storage control module is available, it should be        */
/* attached to the FatFs via a glue function rather than modifying it.   */
/* This is an example of glue functions to attach various exsisting      */
/* storage control modules to the FatFs module with a defined API.       */
/*-----------------------------------------------------------------------*/

#include "ff.h"			/* Obtains integer types */
#include "diskio.h"		/* Declarations of disk functions */
#include "sdmmc/sdmmc.h"
#include "../crypto.h"
#include "../i2c.h"

/* Definitions of physical drive number for each drive */
#define SDCARD        0
#define CTRNAND       1

/*-----------------------------------------------------------------------*/
/* Get Drive Status                                                      */
/*-----------------------------------------------------------------------*/

DSTATUS disk_status (
    BYTE pdrv		/* Physical drive nmuber to identify the drive */
)
{
    (void)pdrv;
    return RES_OK;
}



/*-----------------------------------------------------------------------*/
/* Inidialize a Drive                                                    */
/*-----------------------------------------------------------------------*/

DSTATUS disk_initialize (
    BYTE pdrv				/* Physical drive nmuber to identify the drive */
)
{
    static u32 sdmmcInitResult = 4;
    DSTATUS res = 0;

    if(sdmmcInitResult == 4)
        sdmmcInitResult = sdmmc_sdcard_init();

    // Check physical drive initialized status
    switch (pdrv)
    {
        case SDCARD:
            res = (sdmmcInitResult & 2) == 0 ? 0 : STA_NOINIT;
            break;
        case CTRNAND:
            // Always update CTRNAND parameters when remounting
            res = (sdmmcInitResult & 1) == 0 && ctrNandInit() == 0 ? 0 : STA_NOINIT;
            break;
        default:
            res = STA_NODISK;
            break;
    }

    return res;
}



/*-----------------------------------------------------------------------*/
/* Read Sector(s)                                                        */
/*-----------------------------------------------------------------------*/

DRESULT disk_read (
    BYTE pdrv,		/* Physical drive nmuber to identify the drive */
    BYTE *buff,		/* Data buffer to store read data */
    LBA_t sector,	/* Start sector in LBA */
    UINT count		/* Number of sectors to read */
)
{
    DRESULT res = RES_OK;

    switch (pdrv)
    {
        case SDCARD:
            res = sdmmc_sdcard_readsectors(sector, count, buff) == 0 ? RES_OK : RES_PARERR;
            break;
        case CTRNAND:
            res = ctrNandRead(sector, count, buff) == 0 ? RES_OK : RES_PARERR;
            break;
        default:
            res = RES_NOTRDY;
            break;
    }

    return res;
}



/*-----------------------------------------------------------------------*/
/* Write Sector(s)                                                       */
/*-----------------------------------------------------------------------*/

#if FF_FS_READONLY == 0

DRESULT disk_write (
    BYTE pdrv,			/* Physical drive nmuber to identify the drive */
    const BYTE *buff,	/* Data to be written */
    LBA_t sector,		/* Start sector in LBA */
    UINT count			/* Number of sectors to write */
)
{
    DRESULT res = RES_OK;

    switch (pdrv)
    {
        case SDCARD:
        {
            if ((*(vu16 *)(SDMMC_BASE + REG_SDSTATUS0) & TMIO_STAT0_WRPROTECT) == 0) // why == 0?
                res = RES_WRPRT;
            else
                res = sdmmc_sdcard_writesectors(sector, count, buff) == 0 ? RES_OK : RES_PARERR;
            break;
        }
        case CTRNAND:
            res = ctrNandWrite(sector, count, buff) == 0 ? RES_OK : RES_PARERR;
            break;
        default:
            res = RES_NOTRDY;
            break;
    }

    return res;
}
#endif


/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions                                               */
/*-----------------------------------------------------------------------*/

DRESULT disk_ioctl (
    BYTE pdrv,		/* Physical drive nmuber (0..) */
    BYTE cmd,		/* Control code */
    void *buff		/* Buffer to send/receive control data */
)
{
    (void)pdrv;
    (void)buff;
    return cmd == CTRL_SYNC ? RES_OK : RES_PARERR;
}

// From GodMode9
#define BCDVALID(b) (((b)<=0x99)&&(((b)&0xF)<=0x9)&&((((b)>>4)&0xF)<=0x9))
#define BCD2NUM(b)  (BCDVALID(b) ? (((b)&0xF)+((((b)>>4)&0xF)*10)) : 0xFF)
#define NUM2BCD(n)  ((n<99) ? (((n/10)*0x10)|(n%10)) : 0x99)
#define DSTIMEGET(bcd,n) (BCD2NUM((bcd)->n))

// see: http://3dbrew.org/wiki/I2C_Registers#Device_3 (register 30)
typedef struct DsTime {
    u8 bcd_s;
    u8 bcd_m;
    u8 bcd_h;
    u8 weekday;
    u8 bcd_D;
    u8 bcd_M;
    u8 bcd_Y;
    u8 leap_count;
} DsTime;

/*-----------------------------------------------------------------------*/
/* Get current FAT time                                                  */
/*-----------------------------------------------------------------------*/

DWORD get_fattime( void ) {
    DsTime dstime;
    I2C_readRegBuf(I2C_DEV_MCU, 0x30, (u8 *)&dstime, sizeof(DsTime));
    DWORD fattime =
        ((DSTIMEGET(&dstime, bcd_s)&0x3F) >> 1 ) |
        ((DSTIMEGET(&dstime, bcd_m)&0x3F) << 5 ) |
        ((DSTIMEGET(&dstime, bcd_h)&0x3F) << 11) |
        ((DSTIMEGET(&dstime, bcd_D)&0x1F) << 16) |
        ((DSTIMEGET(&dstime, bcd_M)&0x0F) << 21) |
        (((DSTIMEGET(&dstime, bcd_Y)+(2000-1980))&0x7F) << 25);

    return fattime;
}