#ifndef UNDAR_LIBC_H
#define UNDAR_LIBC_H

#if defined(__has_include)
#if __has_include(<stdint.h>)
#define HAVE_STDINT 1
#endif
#if __has_include(<stdbool.h>)
#define HAVE_STDBOOL 1
#endif
#if __has_include(<stddef.h>)
#define HAVE_STDDEF 1
#endif
#endif

#ifdef HAVE_STDINT
#include <stdint.h>
typedef uint8_t u8;
typedef int8_t i8;
typedef uint16_t u16;
typedef int16_t i16;
typedef uint32_t u32;
typedef int32_t i32;
typedef int32_t r32;
typedef float f32;
#else
typedef unsigned char u8;
typedef signed char i8;
typedef unsigned short u16;
typedef signed short i16;
typedef unsigned int u32;
typedef signed int i32;
typedef signed int r32;
typedef float f32;
#endif

#ifdef HAVE_STDBOOL
#include <stdbool.h>
#else
#define true 1
#define false 0
typedef u8 bool;
#endif

#ifdef HAVE_STDDEF
#include <stddef.h>
#define nil NULL
#else
#define nil ((void *)0)
#endif

#define I8_MIN -128
#define I8_MAX 127
#define U8_MAX 255

#define I16_MIN -32768
#define I16_MAX 32767
#define U16_MAX 65535

#define I32_MIN -2147483648
#define I32_MAX 2147483647
#define U32_MAX 4294967295

#define FIXED_CONST 65536.0f

#define AS_INT(v) ((i32)(v))
#define AS_NAT(v) ((u32)(v))
#define AS_REAL(v) ((i32)(v))
#define FLOAT_TO_REAL(v) (((i32)(v)) * FIXED_CONST)
#define REAL_TO_FLOAT(v) (((f32)(v)) / FIXED_CONST)

#define USED(x) ((void)(x))

#define MAX_LEN_REAL32 12
#define MAX_LEN_INT32 11

typedef struct arena_s Arena;
struct arena_s {
	u8 *tape;
	u32 count;
	u32 capacity;
};

void mcpy(void *dest, void *src, u32 n);
i32 scpy(char *to, const char *from, u32 length);
bool seq(const char *s1, const char *s2);
bool sleq(const char *s1, const char *s2, u32 length);
u32 slen(const char *str);
u32 snlen(const char *str, u32 max_len);
void *aalloc(Arena *arena, u32 size);
void *aend(Arena *arena);
void *areturn(Arena *arena, u32 checkpoint, const void *src, u32 size);
u32 afree(Arena *arena);
char *ascpy(Arena *arena, const char *start, u32 length);
void *amcpy(Arena *arena, void *from, u32 length);

#define ARENA_RETURN(arena, ckpt, src_ptr, type)                                      \
	return (type *)areturn(arena, (ckpt), (src_ptr), sizeof(type))

#define ARENA_RETURN_ARRAY(arena, ckpt, src_ptr, type, count)                         \
	return (type *)areturn(arena, (ckpt), (src_ptr), sizeof(type) * (count))

#define ARENA_RETURN_STR(arena, ckpt, src_ptr)                                        \
	return (char *)areturn(arena, (ckpt), (src_ptr), slen(src_ptr))

#define ARENA_RETURN_STRBUF(arena, ckpt, sbuf)                                        \
	char *to_return = StrBuf_toS(arena, sbuf);                                          \
	return (char *)areturn(arena, (ckpt), (to_return), slen(to_return))

r32 int_to_real(i32 i);
i32 real_to_int(r32 f);
r32 float_to_real(f32 f);
f32 real_to_float(r32 r);
r32 real_add(r32 a, r32 b);
r32 real_sub(r32 a, r32 b);
r32 real_mul(r32 a, r32 b);
r32 real_div(r32 a, r32 b);
r32 real_eq(r32 a, r32 b);
r32 real_ne(r32 a, r32 b);
r32 real_lt(r32 a, r32 b);
r32 real_le(r32 a, r32 b);
r32 real_gt(r32 a, r32 b);
r32 real_ge(r32 a, r32 b);
r32 real_neg(r32 f);
r32 real_abs(r32 f);
char *int_to_string(Arena *a, i32 v);
char *nat_to_string(Arena *a, u32 v);
char *real_to_string(Arena *a, r32 q);

#endif