/* date = June 19th 2023 7:27 pm */

#ifndef CORE_H
#define CORE_H

#include <stdint.h>
#include <intrin.h>
#include <stdarg.h>

//- sixten: Base types

typedef uint8_t u8;
typedef uint16_t u16;
typedef uint32_t u32;
typedef uint64_t u64;
typedef int8_t s8;
typedef int16_t s16;
typedef int32_t s32;
typedef int64_t s64;
typedef float r32;
typedef double r64;
typedef u8 b8;
typedef u16 b16;
typedef u32 b32;
typedef uintptr_t umm;
typedef intptr_t smm;

//- sixten: Base type limits

#define U8_Min  0x00
#define U8_Max  0xFF
#define U16_Min 0x0000
#define U16_Max 0xFFFF
#define U32_Min 0x00000000
#define U32_Max 0xFFFFFFFF
#define U64_Min 0x0000000000000000
#define U64_Max 0xFFFFFFFFFFFFFFFF
#define S8_Min  0x80
#define S8_Max  0x7F
#define S16_Min 0x8000
#define S16_Max 0x7FFF
#define S32_Min 0x80000000
#define S32_Max 0x7FFFFFFF
#define S64_Min 0x8000000000000000
#define S64_Max 0x7FFFFFFFFFFFFFFF

//- sixten: Keywords

#define global static
#define persist static

#pragma section(".roglob", read)
#define read_only __declspec(allocate(".roglob"))

#define per_thread __declspec(thread)

#define fallthrough

//- sixten: Assertions & debugging

#if VN_SLOW
#define Assert(Statement) if(!(Statement)) { *(int *)0 = 0; }
#else
#define Assert(Statement)
#endif

#define CTAssert(Statement) static_assert(Statement)

#define InvokeDebugger __debugbreak()
#define UnimplementedCodepath Assert(!"Unimplemented codepath")

#define InvalidCodepath Assert(!"Invalid codepath")
#define InvalidDefaultCase default: { Assert(!"Invalid codepath"); } break

//- sixten: Array & pointer manipulation

#define ArrayCount(Array) (sizeof(Array)/sizeof((Array)[0]))
#define OffsetOf(type, Member) (umm) &(((type *)0)->Member)

#define PointerToU64(x) ((u64)(void *)x)
#define U64ToPointer(x) ((void *)(u64)x)

//- sixten: Min, max & clamp

#define Minimum(A, B) (((A)<(B))?(A):(B))
#define Maximum(A, B) (((A)>(B))?(A):(B))

#define Clamp(Value, Min, Max) Minimum(Maximum(Value, Min), Max)
#define Clamp01(Value) Clamp(Value, 0, 1)

//- sixten: Linked list helpers

#define IsNull(x) ((x) == 0)
#define SetNull(x) ((x) = 0)

#define DLLInsert_NP(f,l,p,n,next,prev) \
(IsNull(f) ? (((f) = (l) = (n)), SetNull((n)->next), SetNull((n)->prev)) :\
IsNull(p) ? (SetNull((n)->prev), (n)->next = (f), (IsNull(f) ? (0) : ((f)->prev = (n))), (f) = (n)) :\
((IsNull((p)->next) ? (0) : (((p)->next->prev) = (n))), (n)->next = (p)->next, (n)->prev = (p), (p)->next = (n),\
((p) == (l) ? (l) = (n) : (0))))

#define DLLInsertLast_NP(f,l,n,next,prev) DLLInsert_NP(f,l,l,n,next,prev)
#define DLLInsertFirst_NP(f,l,n,next,prev) DLLInsert_NP(l,f,f,n,prev,next)

#define DLLRemove_NP(f,l,n,next,prev)\
(((f)==(n))?\
((f)=(f)->next, (IsNull(f) ? (SetNull(l)) : SetNull((f)->prev))):\
((l)==(n))?\
((l)=(l)->prev, (IsNull(l) ? (SetNull(f)) : SetNull((l)->next))):\
((IsNull((n)->next) ? (0) : ((n)->next->prev=(n)->prev)),\
(IsNull((n)->prev) ? (0) : ((n)->prev->next=(n)->next))))

#define DLLInsertFirst(First, Last, Element) DLLInsertFirst_NP(First, Last, Element, Next, Prev)
#define DLLInsertLast(First, Last, Element) DLLInsertLast_NP(First, Last, Element, Next, Prev)
#define DLLRemove(First, Last, Element) DLLRemove_NP(First, Last, Element, Next, Prev)
#define DLLIsEmpty(First) ((First) == 0)

//- sixten: Stringify 

#define _Stringify(x) #x
#define Stringify(x) _Stringify(x)

//- sixten: Defer loop

#define DeferLoop(Start, End) for(s32 ___ = ((Start), 0); ___ == 0; ++___, (End))

//- sixten: Atomics

inline u64 AtomicExchangeU64(u64 volatile *Value, u64 New)
{
    u64 Result = _InterlockedExchange64((__int64 volatile *)Value, New);
    return(Result);
}

inline u64 AtomicAddU64(u64 volatile *Value, u64 Addend)
{
    u64 Result = _InterlockedExchangeAdd64((__int64 volatile *)Value, Addend);
    return(Result);
}

// sixten: Memory mutexes

struct ticket_mutex
{
    u64 volatile Ticket;
    u64 volatile Serving;
};

inline void BeginTicketMutex(ticket_mutex *Mutex)
{
    u64 Ticket = AtomicAddU64(&Mutex->Ticket, 1);
    while(Ticket != Mutex->Serving) { _mm_pause(); }
}

inline void EndTicketMutex(ticket_mutex *Mutex)
{
    AtomicAddU64(&Mutex->Serving, 1);
} 

//- sixten: Axes

enum axis2
{
    Axis2_X,
    Axis2_Y,
    Axis2_Count
};

inline axis2 Opposite(axis2 Axis) { axis2 Result = (axis2)(!(u32)Axis); return(Result); }

#endif //CORE_H