/**
  ******************************************************************************
  * @file           : object.h
  * @author         : simon
  * @brief          : None
  * @attention      : None
  * @date           : 2023/8/23
  ******************************************************************************
  */

#ifndef CLOX_OBJECT_H
#define CLOX_OBJECT_H

#include "chunk.h"
#include "common.h"
#include "value.h"

#define OBJ_TYPE(value) (AS_OBJ(value)->type)

#define IS_CLOSURE(value) isObjType(value, OBJ_CLOSURE)
#define IS_FUNCTION(value) isObjType(value, OBJ_FUNCTION)
#define IS_NATIVE(value) isObjType(value, OBJ_NATIVE)
#define IS_STRING(value) isObjType(value, OBJ_STRING)

#define AS_CLOSURE(value) ((ObjClosure *) AS_OBJ(value))
#define AS_FUNCTION(value) ((ObjFunction *) AS_OBJ(value))
#define AS_NATIVE(value) (((ObjNative *) AS_OBJ(value))->function)
#define AS_STRING(value) ((ObjString *) AS_OBJ(value))
#define AS_CSTRING(value) (((ObjString *) AS_OBJ(value))->chars)

typedef enum {
  OBJ_STRING,
  OBJ_FUNCTION,
  OBJ_NATIVE,
  OBJ_CLOSURE,
  OBJ_UPVALUE,
} ObjType;

struct Obj {
  ObjType type;
  struct Obj *next;
};

typedef struct {
  struct Obj obj;
  int arity;//  stores the number of parameters the function expects
  int upvalueCount;
  Chunk chunk;
  ObjString *name;
} ObjFunction;

typedef Value (*NativeFn)(int argCount, Value *args);

typedef struct {
  struct Obj obj;
  NativeFn function;
} ObjNative;

struct ObjString {
  struct Obj obj;
  int length;
  char *chars;
  uint32_t hash;// 缓存 hash 值
};

typedef struct ObjUpvalue {
  struct Obj obj;
  Value *location;
  Value closed;
  struct ObjUpvalue *next;
} ObjUpvalue;

typedef struct {
  struct Obj obj;
  ObjFunction *function;
  ObjUpvalue **upvalues;
  int upvalueCount;
} ObjClosure;

ObjClosure *newClosure(ObjFunction *function);
ObjFunction *newFunction();
ObjNative *newNative(NativeFn function);
ObjString *takeString(char *chars, int length);
ObjString *copyString(const char *chars, int length);
ObjUpvalue *newUpvalue(Value *slot);
void printObject(Value value);

static inline bool isObjType(Value value, ObjType type) {
  return IS_OBJ(value) && AS_OBJ(value)->type == type;
}

#endif//CLOX_OBJECT_H