#ifndef R_ENDIAN_H
#define R_ENDIAN_H

#include "r_types.h"


#if R_CHECKS_LEVEL == 0
#define R_QUIET_FAIL(expr) do { ; } while(0)
#else
#define R_QUIET_FAIL(expr) if (!(expr)) { assert (false); }
#endif

#ifdef __cplusplus
extern "C" {
#endif

/* Endian agnostic functions working on single byte. */

static inline ut8 r_read_ble8(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	return *(const ut8 *)src;
}

static inline ut8 r_read_at_ble8(const void *src, size_t offset) {
	return r_read_ble8 (((const ut8*)src) + offset);
}

static inline void r_write_ble8(void *dest, ut8 val) {
	*(ut8 *)dest = val;
}

static inline void r_write_at_ble8(void *dest, ut8 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_ble8 (d, val);
}

/* Big Endian functions. */

static inline ut8 r_read_be8(const void *src) {
	return r_read_ble8 (src);
}

static inline ut8 r_read_at_be8(const void *src, size_t offset) {
	return r_read_at_ble8 (src, offset);
}

static inline void r_write_be8(void *dest, ut8 val) {
	r_write_ble8 (dest, val);
}

static inline void r_write_at_be8(void *dest, ut8 val, size_t offset) {
	r_write_at_ble8 (dest, val, offset);
}

static inline ut16 r_read_be16(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut16)s[0]) << 8) | (((ut16)s[1]) << 0);
}

static inline ut16 r_read_at_be16(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_be16 (s);
}

static inline void r_write_be16(void *dest, ut16 val) {
	r_write_be8 (dest, val >> 8);
	r_write_at_be8 (dest, (ut8)val, sizeof (ut8));
}

static inline void r_write_at_be16(void *dest, ut16 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_be16 (d, val);
}

static inline ut32 r_read_be24(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut32)s[0]) << 16) | (((ut32)s[1]) << 8) | (((ut32)s[2]) << 0);
}

static inline void r_write_be24(void *_dest, ut32 val) {
	ut8 *dest = (ut8*)_dest;
	r_write_be8 (dest++, val >> 16);
	r_write_be8 (dest++, val >> 8);
	r_write_be8 (dest, val);
}

static inline ut32 r_read_be32(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut32)s[0]) << 24) | (((ut32)s[1]) << 16) |
		(((ut32)s[2]) << 8) | (((ut32)s[3]) << 0);
}

static inline ut32 r_read_at_be32(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_be32 (s);
}

static inline void r_write_be32(void *dest, ut32 val) {
	r_write_be16 (dest, val >> 16);
	r_write_at_be16 (dest, val, sizeof (ut16));
}

static inline void r_write_at_be32(void *dest, ut32 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_be32 (d, val);
}

static inline ut64 r_read_be64(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	ut64 val = ((ut64)(r_read_be32 (src))) << 32;
	val |= r_read_at_be32 (src, sizeof (ut32));
	return val;
}

static inline ut64 r_read_at_be64(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_be64 (s);
}

static inline void r_write_be64(void *dest, ut64 val) {
	r_write_be32 (dest, val >> 32);
	r_write_at_be32 (dest, (ut32)val, sizeof (ut32));
}

static inline void r_write_at_be64(void *dest, ut64 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_be64 (d, val);
}

/* Little Endian functions. */

static inline ut8 r_read_le8(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	return r_read_ble8 (src);
}

static inline ut8 r_read_at_le8(const void *src, size_t offset) {
	return r_read_at_ble8 (src, offset);
}

static inline void r_write_le8(void *dest, ut8 val) {
	r_write_ble8 (dest, val);
}

static inline void r_write_at_le8(void *dest, ut8 val, size_t offset) {
	r_write_at_ble8 (dest, val, offset);
}

static inline ut16 r_read_le16(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut16)s[1]) << 8) | (((ut16)s[0]) << 0);
}

static inline ut16 r_read_at_le16(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_le16 (s);
}

static inline void r_write_le16(void *dest, ut16 val) {
	r_write_le8 (dest, (ut8)val);
	r_write_at_le8 (dest, val >> 8, sizeof (ut8));
}

static inline void r_write_at_le16(void *dest, ut16 val, size_t offset) {
	ut8 *d = (ut8 *)dest + offset;
	r_write_le16 (d, val);
}

static inline void r_write_le24(void *_dest, ut32 val) {
	ut8* dest = (ut8*)_dest;
	r_write_le8 (dest++, val);
	r_write_le8 (dest++, val >> 8);
	r_write_le8 (dest,   val >> 16);
}

static inline ut32 r_read_le24(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut32)s[2]) << 16) | (((ut32)s[1]) << 8) | (((ut32)s[0]) << 0);
}

static inline ut32 r_read_le32(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut32)s[3]) << 24) | (((ut32)s[2]) << 16) |
		(((ut32)s[1]) << 8) | (((ut32)s[0]) << 0);
}

static inline ut32 r_read_at_le32(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_le32 (s);
}

static inline void r_write_le32(void *dest, ut32 val) {
	r_write_le16 (dest, val);
	r_write_at_le16 (dest, val >> 16, sizeof (ut16));
}

static inline void r_write_at_le32(void *dest, ut32 val, size_t offset) {
	ut8 *d = ((ut8*)dest) + offset;
	r_write_le32 (d, val);
}

static inline ut64 r_read_le64(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	ut64 val = ((ut64)(r_read_at_le32 (src, sizeof (ut32)))) <<  32;
	val |= r_read_le32 (src);
	return val;
}

static inline ut64 r_read_at_le64(const void *src, size_t offset) {
	const ut8 *s = ((const ut8*)src) + offset;
	return r_read_le64 (s);
}

static inline void r_write_le64(void *dest, ut64 val) {
	r_write_le32 (dest, (ut32)val);
	r_write_at_le32 (dest, val >> 32, sizeof (ut32));
}

static inline void r_write_at_le64(void *dest, ut64 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_le64 (d, val);
}

/* Middle Endian functions. */

static inline ut8 r_read_me8(const void *src) {
	return r_read_ble8 (src);
}

static inline ut8 r_read_at_me8(const void *src, size_t offset) {
	return r_read_at_ble8 (src, offset);
}

static inline void r_write_me8(void *dest, ut8 val) {
	r_write_ble8 (dest, val);
}

static inline void r_write_at_me8(void *dest, ut8 val, size_t offset) {
	r_write_at_ble8 (dest, val, offset);
}

static inline ut16 r_read_me16(const void *src) {
	return r_read_be16 (src);
}

static inline ut16 r_read_at_me16(const void *src, size_t offset) {
	return r_read_me16 (((ut8*)src) + offset);
}

static inline void r_write_me16(void *dest, ut16 val) {
	r_write_me8 (dest, val >> 8);
	r_write_at_me8 (dest, (ut8)val, sizeof (ut8));
}

static inline void r_write_at_me16(void *dest, ut16 val, size_t offset) {
	ut8 *d = (ut8 *)dest + offset;
	r_write_me16 (d, val);
}

static inline ut32 r_read_me32(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	const ut8 *s = (const ut8*)src;
	return (((ut32)s[2]) << 24) | (((ut32)s[1]) << 16) |
		(((ut32)s[0]) << 8) | (((ut32)s[1]) << 0);
}

static inline ut32 r_read_at_me32(const void *src, size_t offset) {
	const ut8 *s = (const ut8*)src + offset;
	return r_read_me32 (s);
}

static inline void r_write_me32(void *dest, ut32 val) {
	r_write_me16 (dest, val);
	r_write_at_me16 (dest, val >> 16, sizeof (ut16));
}

static inline void r_write_at_me32(void *dest, ut32 val, size_t offset) {
	ut8 *d = ((ut8*)dest) + offset;
	r_write_me32 (d, val);
}

static inline ut64 r_read_me64(const void * R_NONNULL src) {
	R_QUIET_FAIL (src);
	ut64 val = ((ut64)(r_read_at_me32 (src, sizeof (ut32)))) <<  32;
	val |= r_read_me32 (src);
	return val;
}

static inline ut64 r_read_at_me64(const void *src, size_t offset) {
	const ut8 *s = ((const ut8*)src) + offset;
	return r_read_me64 (s);
}

static inline void r_write_me64(void *dest, ut64 val) {
	r_write_me32 (dest, (ut32)val);
	r_write_at_me32 (dest, val >> 32, sizeof (ut32));
}

static inline void r_write_at_me64(void *dest, ut64 val, size_t offset) {
	ut8 *d = (ut8*)dest + offset;
	r_write_me64 (d, val);
}

/* Helper functions --- this is all spaguetti that can be rewritten with 1 line macro */

static inline ut16 r_read_ble16(const void *src, bool be) {
	return be? r_read_be16 (src): r_read_le16 (src);
}

static inline ut32 r_read_ble24(const void *src, bool be) {
	return be? r_read_be24 (src): r_read_le24 (src);
}

static inline ut32 r_read_ble32(const void *src, bool be) {
	return be? r_read_be32 (src): r_read_le32 (src);
}

static inline ut64 r_read_ble64(const void *src, bool be) {
	return be? r_read_be64 (src): r_read_le64 (src);
}

static inline ut16 r_read_at_ble16(const void *src, size_t offset, bool be) {
	return be ? r_read_at_be16 (src, offset) : r_read_at_le16 (src, offset);
}

static inline ut32 r_read_at_ble32(const void *src, size_t offset, bool be) {
	return be ? r_read_at_be32 (src, offset) : r_read_at_le32 (src, offset);
}

static inline ut64 r_read_at_ble64(const void *src, size_t offset, bool be) {
	return be ? r_read_at_be64 (src, offset) : r_read_at_le64 (src, offset);
}

static inline ut64 r_read_ble(const void *src, bool be, int size) {
	switch (size) {
	case 8:
		return (ut64) ((const ut8*)src)[0];
	case 16:
		return r_read_ble16 (src, be);
	case 32:
		return r_read_ble32 (src, be);
	case 64:
		return r_read_ble64 (src, be);
	default:
		return UT64_MAX;
	}
}

static inline void r_write_ble16(void *dest, ut16 val, bool be) {
	be? r_write_be16 (dest, val): r_write_le16 (dest, val);
}

static inline void r_write_ble24(void *dest, ut32 val, bool be) {
	be? r_write_be24 (dest, val): r_write_le24 (dest, val);
}

static inline void r_write_ble32(void *dest, ut32 val, bool be) {
	be? r_write_be32 (dest, val): r_write_le32 (dest, val);
}

static inline void r_write_ble64(void *dest, ut64 val, bool be) {
	be? r_write_be64 (dest, val): r_write_le64 (dest, val);
}

static inline void r_write_ble(void *dst, ut64 val, bool be, int size) {
	switch (size) {
	case 8:
		((ut8*)dst)[0] = (ut8) val;
		break;
	case 16:
		r_write_ble16 (dst, (ut16) val, be);
		break;
	case 24:
		r_write_ble24 (dst, (ut32) val, be);
		break;
	case 32:
		r_write_ble32 (dst, (ut32) val, be);
		break;
	case 64:
		r_write_ble64 (dst, val, be);
		break;
	default:
		break;
	}
}


/*swap*/
static inline ut16 r_swap_ut16(ut16 val) {
	return (val << 8) | (val >> 8 );
}

static inline st16 r_swap_st16(st16 val) {
	val = ((val << 8) & 0xFF00FF00 ) | ((val >> 8) & 0xFF00FF );
	return (val << 16) | (val >> 16);
}

static inline ut32 r_swap_ut32(ut32 val) {
	val = ((val << 8) & 0xFF00FF00 ) | ((val >> 8) & 0xFF00FF );
	return (val << 16) | (val >> 16);
}

static inline st32 r_swap_st32(st32 val) {
	val = ((val << 8) & 0xFF00FF00) | ((val >> 8) & 0xFF00FF );
	return (val << 16) | ((val >> 16) & 0xFFFF);
}

static inline ut64 r_swap_ut64(ut64 val) {
	val = ((val << 8) & 0xFF00FF00FF00FF00ULL ) | ((val >> 8) & 0x00FF00FF00FF00FFULL );
	val = ((val << 16) & 0xFFFF0000FFFF0000ULL ) | ((val >> 16) & 0x0000FFFF0000FFFFULL );
	return (val << 32) | (val >> 32);
}

static inline st64 r_swap_st64(st64 val) {
	val = ((val << 8) & 0xFF00FF00FF00FF00ULL ) | ((val >> 8) & 0x00FF00FF00FF00FFULL );
	val = ((val << 16) & 0xFFFF0000FFFF0000ULL ) | ((val >> 16) & 0x0000FFFF0000FFFFULL );
	return (val << 32) | ((val >> 32) & 0xFFFFFFFFULL);
}

/* Some "secured" functions, to do basic operation (mul, sub, add...) on integers */
static inline int UT64_ADD(ut64 *r, ut64 a, ut64 b) {
	if (UT64_MAX - a < b) {
		return 0;
	}
	if (r) {
		*r = a + b;
	}
	return 1;
}

static inline int UT64_MUL(ut64 *r, ut64 a, ut64 b) {
	if (a && UT64_MAX / a < b) {
		return 0;
	}
	if (r) {
		*r = a * b;
	}
	return 1;
}

static inline int UT64_SUB(ut64 *r, ut64 a, ut64 b) {
	if (b > a) {
		return 0;
	}
	if (r) {
		*r = a - b;
	}
	return 1;
}

static inline int UT32_ADD(ut32 *r, ut32 a, ut32 b) {
	if (UT32_MAX - a < b) {
		return 0;
	}
	if (r) {
		*r = a + b;
	}
	return 1;
}

static inline int UT32_MUL(ut32 *r, ut32 a, ut32 b) {
	if (a && UT32_MAX / a < b) {
		return 0;
	}
	if (r) {
		*r = a * b;
	}
	return 1;
}

static inline int UT32_SUB(ut32 *r, ut32 a, ut32 b) {
	if (b > a) {
		return 0;
	}
	if (r) {
		*r = a - b;
	}
	return 1;
}

static inline int UT16_ADD(ut16 *r, ut16 a, ut16 b) {
	if (UT16_MAX - a < b) {
		return 0;
	}
	if (r) {
		*r = a + b;
	}
	return 1;
}

static inline int UT16_MUL(ut16 *r, ut16 a, ut16 b) {
	if (a && UT16_MAX / a < b) {
		return 0;
	}
	if (r) {
		*r = a * b;
	}
	return 1;
}

static inline int UT16_SUB(ut16 *r, ut16 a, ut16 b) {
	if (b > a) {
		return 0;
	}
	if (r) {
		*r = a - b;
	}
	return 1;
}

static inline int UT8_ADD(ut8 *r, ut8 a, ut8 b) {
	if (UT8_MAX - a < b) {
		return 0;
	}
	if (r) {
		*r = a + b;
	}
	return 1;
}

static inline int UT8_MUL(ut8 *r, ut8 a, ut8 b) {
	if (a && UT8_MAX / a < b) {
		return 0;
	}
	if (r) {
		*r = a * b;
	}
	return 1;
}

static inline int UT8_SUB(ut8 *r, ut8 a, ut8 b) {
	if (b > a) {
		return 0;
	}
	if (r) {
		*r = a - b;
	}
	return 1;
}

#ifdef __cplusplus
}
#endif

#endif