#ifndef __VB_H__
#define __VB_H__

#ifdef __cplusplus
extern "C" {
#endif

#ifndef VBAPI
#define VBAPI extern
#endif

/* Header includes */
#include <stddef.h>
#include <stdint.h>



/********************************* Constants *********************************/

/* Value types */
#define VB_S8  0
#define VB_U8  1
#define VB_S16 2
#define VB_U16 3
#define VB_S32 4

/* System register IDs */
#define VB_ADTRE 25
#define VB_CHCW  24
#define VB_ECR    4
#define VB_EIPC   0
#define VB_EIPSW  1
#define VB_FEPC   2
#define VB_FEPSW  3
#define VB_PIR    6
#define VB_PSW    5
#define VB_TKCW   7



/*********************************** Types ***********************************/

/* Simulation state */
typedef struct VB VB;
struct VB {

    /* Game pak */
    struct {
        uint8_t *rom;      /* Active ROM buffer */
        uint32_t romSize;  /* Size of ROM data */
        uint8_t *sram;     /* Active SRAM buffer */
        uint32_t sramSize; /* Size of SRAM data */
    } cart;

    /* CPU */
    struct {

        /* System registers */
        uint32_t adtre; /* Address trap register for execution */
        uint32_t eipc;  /* Exception/Interrupt PC  */
        uint32_t eipsw; /* Exception/Interrupt PSW */
        uint32_t fepc;  /* Fatal error PC */
        uint32_t fepsw; /* Fatal error PSW */
        uint32_t sr29;  /* Unknown system register */
        uint32_t sr31;  /* Unknown system register */

        /* Cache control word */
        struct {
            int8_t ice; /* Instruction cache enable */
        } chcw;

        /* Exception cause register */
        struct {
            uint16_t eicc; /* Exception/interrupt cause code */
            uint16_t fecc; /* Fatal error cause code */
        } ecr;

        /* Program status word */
        struct {
            int8_t ae;  /* Address trap enable */
            int8_t cy;  /* Carry */
            int8_t ep;  /* Exception pending */
            int8_t fiv; /* Floating invalid */
            int8_t fov; /* Floating overflow */
            int8_t fpr; /* Floating precision */
            int8_t fro; /* Floating reserved operand */
            int8_t fud; /* Floating underflow */
            int8_t fzd; /* Floating zero divide */
            int8_t i;   /* Interrupt level */
            int8_t id;  /* Interrupt disable */
            int8_t np;  /* NMI pending */
            int8_t ov;  /* Overflow */
            int8_t s;   /* Sign */
            int8_t z;   /* Zero */
        } psw;

        /* Other registers */
        uint32_t pc;          /* Program counter */
        int32_t  program[32]; /* program registers */

        /* Other fields */
        uint32_t clocks; /* Clocks until next action */
        uint8_t  fatch;  /* Index of fetch unit */
        uint8_t  state;  /* Operations state */
    } cpu;

    /* Other fields */
    uint8_t wram[0x10000]; /* Main memory */
};



/**************************** Function Prototypes ****************************/

VBAPI uint32_t vbGetProgramCounter  (VB *emu);
VBAPI int32_t  vbGetProgramRegister (VB *emu, int id);
VBAPI uint32_t vbGetSystemRegister  (VB *emu, int id);
VBAPI void     vbInit               (VB *emu);
VBAPI int32_t  vbRead               (VB *emu, uint32_t address, int type, int debug);
VBAPI void     vbReset              (VB *emu);
VBAPI uint32_t vbSetProgramCounter  (VB *emu, uint32_t value);
VBAPI int32_t  vbSetProgramRegister (VB *emu, int id, int32_t value);
VBAPI int      vbSetROM             (VB *emu, void *rom, uint32_t size);
VBAPI int      vbSetSRAM            (VB *emu, void *sram, uint32_t size);
VBAPI uint32_t vbSetSystemRegister  (VB *emu, int id, uint32_t value);
VBAPI void     vbWrite              (VB *emu, uint32_t address, int type, int32_t value, int debug);



#ifdef __cplusplus
}
#endif

#endif /* __VB_H__ */