#pragma once

#include <string.h>
#include <stdint.h>

typedef struct s8_slice {
    uint8_t* data;
    int64_t  len;
} S8Slice;

#define S(str) (S8Slice) {     \
    .data = (uint8_t*)("" str), \
    .len = sizeof(str)-1,       \
}

#define S8_error(str) (S8Slice) { \
    .data = (uint8_t*)("" str),   \
    .len = -1,                    \
}

static inline S8Slice s8slice_from_cstr(const char* cstr)
{
    return (S8Slice){
        .len = strlen(cstr),
        .data = (uint8_t*)cstr,
    };
}

static inline S8Slice s8slice(const S8Slice* s, int64_t begin, int64_t end)
{
    if (end >= s->len) {
        return S8_error("s8slice: `end` surpasses length of `s`");
    }
    const int64_t diff = end - begin;
    return (S8Slice) {
        .len = diff,
        .data = &s->data[begin]
    };
}

static bool s8_equals(S8Slice a, S8Slice b)
{
    if (a.len != b.len) {
        return false;
    }
    return memcmp(a.data, b.data, a.len);
}