/*
File:   cwasm.h
Author: Taylor Robbins
Date:   08\28\2025
Description:
	** This header should be included before any other header and at the top of every compilation unit.
	** It in turn includes any files that are needed for a CWasm-based application to function
*/

#ifndef _CWASM_H
#define _CWASM_H

// +--------------------------------------------------------------+
// |                        Check Compiler                        |
// +--------------------------------------------------------------+
#if !defined(__clang__)
#error CWasm is only tested to function with Clang as the compiler!
#endif
#if !defined(__clang_major__) || !defined(__clang_minor__) || !defined(__clang_patchlevel__)
#error Missing defines for __clang_major__, __clang_minor__, and __clang_patchlevel__!
#endif
#if !defined(__wasm32__)
#error CWasm only works when compiling for 32-bit WebAssembly!
#endif
#if defined(__EMSCRIPTEN__)
#error CWasm is not meant to be compiled with Emscripten. It functions as a standalone platform for C applications that only depend on a small subset of the C standard library
#endif
#ifndef __BYTE_ORDER__
#error Missing __BYTE_ORDER__ define!
#elif __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
#error This standard library implementation assumes little-endian byte order
#endif

#ifdef __cplusplus
#define LANGUAGE_IS_C   0
#define LANGUAGE_IS_CPP 1
#else
#define LANGUAGE_IS_C   1
#define LANGUAGE_IS_CPP 0
#endif

#if LANGUAGE_IS_C
#define nullptr ((void*)0)
#endif

#define START_EXTERN_C extern "C" {
#define END_EXTERN_C   }
#if LANGUAGE_IS_CPP
#define MAYBE_EXTERN_C       EXTERN_C
#define MAYBE_START_EXTERN_C START_EXTERN_C
#define MAYBE_END_EXTERN_C   END_EXTERN_C
#else
#define MAYBE_EXTERN_C       //nothing
#define MAYBE_START_EXTERN_C //nothing
#define MAYBE_END_EXTERN_C   //nothing
#endif

#define WASM_MEMORY_PAGE_SIZE      (64*1024ULL) //64kB or 65,536b
#define WASM_MEMORY_MAX_NUM_PAGES  (64*1024ULL) //65,536 pages * 64 kB/page = 4GB
#define WASM_MEMORY_MAX_SIZE       ((u64)WASM_MEMORY_MAX_NUM_PAGES * (u64)WASM_MEMORY_PAGE_SIZE)
#define WASM_PROTECTED_SIZE        1024       //1kB at start of wasm memory should be unused and should never be written to

#define WASM_EXPORT(functionName) MAYBE_EXTERN_C __attribute__((export_name(#functionName)))

// +--------------------------------------------------------------+
// |                      Standard Includes                       |
// +--------------------------------------------------------------+
// NOTE: These headers are all contained in CWasm's "std" folder, they are not "real" C standard library headers
#include <stdint.h>
#include <string.h>

// +--------------------------------------------------------------+
// |                       Basic Type Names                       |
// +--------------------------------------------------------------+
// We use an "i" to indicate it can hold integer numbers
typedef int8_t      i8;
typedef int16_t     i16;
typedef int32_t     i32;
typedef long long   i64;

// We use a "u" to distinguish these as only holding unsigned numbers (they are still integers, but "i" is already taken)
typedef uint8_t     u8;
typedef uint16_t    u16;
typedef uint32_t    u32;
typedef unsigned long long u64;

// We use an "r" to indicate it can hold real numbers
typedef float       r32;
typedef double      r64;

#endif //  _CWASM_H