// --------------------------------------------------------------------
// Copyright (c) 2007 by Terasic Technologies Inc. 
// --------------------------------------------------------------------
//
// Permission:
//
//   Terasic grants permission to use and modify this code for use
//   in synthesis for all Terasic Development Boards and Altera Development 
//   Kits made by Terasic.  Other use of this code, including the selling 
//   ,duplication, or modification of any portion is strictly prohibited.
//
// Disclaimer:
//
//   This VHDL/Verilog or C/C++ source code is intended as a design reference
//   which illustrates how these types of functions can be implemented.
//   It is the user's responsibility to verify their design for
//   consistency and functionality through the use of formal
//   verification methods.  Terasic provides no warranty regarding the use 
//   or functionality of this code.
//
// --------------------------------------------------------------------
//           
//                     Terasic Technologies Inc
//                     356 Fu-Shin E. Rd Sec. 1. JhuBei City,
//                     HsinChu County, Taiwan
//                     302
//
//                     web: http://www.terasic.com/
//                     email: support@terasic.com
//
// --------------------------------------------------------------------

#ifndef FATINTERNAL_H_
#define FATINTERNAL_H_


#include "FatFileSystem.h"


typedef void *DISK_HANDLE;
typedef bool (*READ_BLOCK512_FUNC)(DISK_HANDLE DiskHandle, alt_u32 PysicalSelector, alt_u8 szBuf[512]);


typedef enum{
    PARTITION_FAT16=6,  // limited to 2G
    PARTITION_FAT32=11,
}PARTITION_TYPE;

typedef struct{
    // Hardware Access Function
    DISK_HANDLE     DiskHandle;
    READ_BLOCK512_FUNC ReadBlock512;
    
    //    
    unsigned int Partition_Type;
    bool bMount;
    //
    unsigned int PartitionStartSecter;
    unsigned int BPB_BytsPerSec;
    unsigned int BPB_SecPerCluster;
    unsigned int BPB_RsvdSecCnt;
    unsigned int BPB_NumFATs;
    unsigned int BPB_RootEntCnt;
    unsigned int BPB_FATSz;
    //
    unsigned int nBytesPerCluster;
    unsigned int FatEntrySecter;
    unsigned int RootDirectoryEntrySecter;
    unsigned int DataEntrySecter;
    //
#ifdef FAT_READONLY    
    char *szFatTable; // read into memory for speedup
#endif
        
    
}VOLUME_INFO;


typedef struct{
    bool IsOpened;
    unsigned int SeekPos;
    unsigned int Cluster;
    unsigned int ClusterSeq; // zero base
    //FAT_DIRECTORY Directory;
    FILE_CONTEXT Directory;
    // 
    FAT_HANDLE Fat;
}FAT_FILE_INFO;


typedef enum{
    CLUSTER_UNUSED,
    CLUSTER_RESERVED,
    CLUSTER_BAD,
    CLUSTER_LAST_INFILE,
    CLUSTER_NEXT_INFILE
}CLUSTER_TYPE;

typedef struct{
    char Name[8];
    char Extension[3];
    char Attribute;
    char reserved[2]; 
    unsigned short CreateTime;
    unsigned short CreateDate;
    unsigned short LastAccessDate;
    unsigned short FirstLogicalClusterHi; // not used in FAT12/FAT16
    unsigned short LastWriteTime;
    unsigned short LastWriteDate;
    unsigned short FirstLogicalCluster;
    unsigned int FileSize;
}fat_packed FAT_DIRECTORY;  //fat_packed

typedef struct{
    char LDIR_Ord;
    char LDIR_Name1[10];
    char LDIR_Attr;  // must be ATTR_LONG_NAME (0x0F)
    char LDIR_Type;
    char LDIR_Chksum;
    char LDIR_Name2[12];
    char LDIR_FstClusLO[2]; // must be zero
    char LDIR_Name3[4]; 
}fat_packed FAT_LONG_DIRECTORY;  //fat_packed


#define ATTR_IBUTE_VOLUME_BIT       (0x01)
#define ATTRIBUTE_DIRECTORY_BIT    (0x01 << 1)
#define ATTRIBUTE_SYSTEM_BIT       (0x01 << 2)
#define ATTRIBUTE_READONLY_BIT     (0x01 << 3)
#define ATTRIBUTE_ARCHIVE_BIT      (0x01 << 4)
#define ATTRIBUTE__BIT             (0x01 << 5)

#define ATTR_READ_ONLY 0x01
#define ATTR_HIDDEN 0x02
#define ATTR_SYSTEM 0x04
#define ATTR_VOLUME_ID 0x08
#define ATTR_DIRECTORY 0x10
#define ATTR_ARCHIVE 0x20
#define ATTR_LONG_NAME (ATTR_READ_ONLY |ATTR_HIDDEN |ATTR_SYSTEM |ATTR_VOLUME_ID)
#define ATTR_LONG_NAME_MASK (ATTR_READ_ONLY |ATTR_HIDDEN |ATTR_SYSTEM |ATTR_VOLUME_ID | ATTR_DIRECTORY | ATTR_ARCHIVE)

#define LAST_LONG_ENTRY         0x40
//
FAT_HANDLE fatMountSdcard(void);
FAT_HANDLE fatMountUsbDisk(DEVICE_HANDLE hDevice);

// internal function
CLUSTER_TYPE fatClusterType(unsigned short Fat);
unsigned int fatNextCluster(VOLUME_INFO *pVol, unsigned short ThisCluster);
void fatDumpDate(unsigned short Date);
void fatDumpTime(unsigned short Date);
bool fatIsValid(FAT_DIRECTORY *pDir);
bool fatIsLast(FAT_DIRECTORY *pDir);
// debug tool
void fatDump(FAT_DIRECTORY *pDirectory);



#endif /*FATINTERNAL_H_*/