#pragma once

// ::Allocator::Util::Header::

usize CalcPaddingWithHeader(uintptr ptr, uintptr alignment, usize header_size);

// ::Allocator::Arena::Header::

#define ARENA_HEADER_SIZE 64

typedef struct Arena
{
	u8		*buffer;
	usize length;
	usize pos;
	u32   init_line_no;
} Arena;

typedef struct TempArena
{
	Arena *arena;
	u64   pos;
} TempArena;

static Arena *CreateArena(rawptr buffer, usize length);
static rawptr ArenaAllocAlign(Arena *arena, usize size, usize align);
static rawptr ArenaAlloc(Arena *arena, usize size);
static void ArenaFree(Arena *arena);
static void ArenaFreeZeroed(Arena *arena);
static void DeallocArena(Arena *arena);
static Arena *CreateArenaDebug(rawptr buffer, usize length, u32 init_line_no);

// ::Allocator::GlobalAlloc::Header::

typedef struct FreeListBuffer
{
	rawptr buf;
	u32 	 size;
	u32		 free_size;
} FreeListBuffer;

typedef struct Allocator
{
	RBNode         *head;
	RBNode         *nil;
	FreeListBuffer *buffers;
	usize          grow_size;
	u8             buf_len;
} Allocator;

static void InitAllocator(usize init_size, usize grow_size);
static void DeinitAlloc();
static void AllocGrow();
static rawptr Alloc(usize size);
static void Free(rawptr ptr);

// ::Allocator::FreeList::Header::

typedef struct FLAllocHeader
{
	usize block_size;
	usize padding;
} FLAllocHeader;

typedef struct FLNode FLNode;

typedef struct FLNode
{
	FLNode *next;
	usize  size;
} FLNode;

typedef struct FLAlloc
{
	rawptr data;
	FLNode *head;
	FLNode *nil;
	usize  size;
	usize  used;
} FLAlloc;

static void FLAllocInit(FLAlloc *alloc, usize size);
static void FLAllocFreeAll(FLAlloc *alloc);
static FLNode *FreeListSearch(FLAlloc *alloc, usize size, u32 alignment, u32 *out_padding, FLNode **prev_node);
static rawptr FreeListAlloc(FLAlloc *alloc, usize size, u32 alignment);