#ifndef __JABYENGINE_SYSCALLS__H
#define __JABYENGINE_SYSCALLS__H
#include "../jabyengine_defines.h"

/*
R0	    zr	    Constant Zero	
R1	    at	    Reserved for the assembler	
R2-R3	v0-v1	Values for results and expression evaluation	
R4-R7	a0-a3	Arguments	
R8-R15	t0-t7	Temporaries (not preserved across call)	
R16-R23	s0-s7	Saved (preserved across call)	
R24-R25	t8-t9	More temporaries (not preserved across call)	
R26-R27	k0-k1	Reserved for OS Kernel	
R28	    gp	    Global Pointer	
R29	    sp	    Stack Pointer	
R30	    fp	    Frame Pointer	
R31 	ra	    Return address (set by function call)
*/

static __constexpr const uint32_t __syscall_Table_A = 0xA0;
static __constexpr const uint32_t __syscall_Table_B = 0xB0;
static __constexpr const uint32_t __syscall_Table_C = 0xC0;

enum __syscall_PriorityChain {
    CdromDmaIrq      = 0, 
    CdromIoIrq       = 0, 
    SyscallException = 0,

    CardSpecificIrq = 1,
    VblankIrq       = 1,
    Timer2Irq       = 1,
    Timer1Irq       = 1,
    Timer0Irq       = 1,

    PadCardIrq = 2,
        
    DefInt = 3
};

static __constexpr const uint32_t SkipHandler    = 0;
static __constexpr const uint32_t ExecuteHandler = 1;

struct __no_align __syscall_InterruptElement {
    struct __syscall_InterruptElement *next;
    void                             (*handler)(uint32_t);
    uint32_t                         (*verifier)();
    uint32_t                           notUsed;
};

#ifdef __cplusplus
    reinterpret_cast<__VA_ARGS__>(table)
#else
    #define __syscall_function_cast(table, ...) ((__VA_ARGS__)(void*)table)
#endif

static __always_inline void* __syscall_memcpy(void *dst, const void *src, size_t len) {
    register uint32_t FuncID asm("t1") = 0x2A;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    return __syscall_function_cast(__syscall_Table_A, void*(*)(void*, const void*, size_t))(dst, src, len);
}

static __always_inline void __syscall_InitPad(uint8_t *portA, uint32_t portASize, uint8_t *portB, uint32_t portBSize) {
    register uint32_t FuncID asm("t1") = 0x12;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    __syscall_function_cast(__syscall_Table_B, void(*)(uint8_t*, uint32_t, uint8_t*, uint32_t))(portA, portASize, portB, portBSize);
}

static __always_inline void __syscall_StartPad() {
    register uint32_t FuncID asm("t1") = 0x13;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    __syscall_function_cast(__syscall_Table_B, void(*)())();
}

static __always_inline void __syscall_StopPad() {
    register uint32_t FuncID asm("t1") = 0x14;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    __syscall_function_cast(__syscall_Table_B, void(*)())();
}

static __always_inline void __syscall_ChangeClearPad(int32_t _reserved) {
    register uint32_t FuncID asm("t1") = 0x5B;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    __syscall_function_cast(__syscall_Table_B, void(*)(int32_t))(_reserved);
}

static __always_inline void __syscall_ReturnFromException() {
    register uint32_t FuncID asm("t1") = 0x17;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    __syscall_function_cast(__syscall_Table_B, void(*)())();
}

static __always_inline int __syscall_SysEnqIntRP(enum __syscall_PriorityChain prio, struct __syscall_InterruptElement* interElm) {
    register uint32_t FuncID asm("t1") = 0x02;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    return __syscall_function_cast(__syscall_Table_C, int(*)(enum __syscall_PriorityChain prio, struct __syscall_InterruptElement *interElm))(prio, interElm);
}

static __always_inline int __syscall_SysDeqIntRP(enum __syscall_PriorityChain prio, struct __syscall_InterruptElement *interElm) {
    register uint32_t FuncID asm("t1") = 0x03;
    __asm__ volatile("" : "=r"(FuncID) : "r"(FuncID));

    return __syscall_function_cast(__syscall_Table_C, int(*)(enum __syscall_PriorityChain prio, struct __syscall_InterruptElement *interElm))(prio, interElm);
}

static __always_inline uint32_t __syscall_EnterCriticalSection() {
    register uint32_t FuncID      asm("a0") = 0x01;
    register uint32_t returnValue asm("v0");

    __asm__ volatile("syscall" : "=r"(FuncID), "=r"(returnValue) : "r"(FuncID) : "at", "v1", "a1", "a2", "a3", "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9", "memory");
    return returnValue;
}

static __always_inline void __syscall_ExitCriticalSection() {
    register uint32_t FuncID asm("a0") = 0x2;

    __asm__ volatile("syscall" : "=r"(FuncID) : "r"(FuncID) : "at", "v0", "v1", "a1", "a2", "a3", "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9", "memory");
}

int __syscall_printf(const char* txt, ...);

#endif //!__JABYENGINE_SYSCALLS__H