#include "kvstore.h"
#include "kvs_rw_tools.h"
#include <arpa/inet.h>
#include <unistd.h>

#if ENABLE_ARRAY
extern kvs_array_t global_array;
#endif

#if ENABLE_RBTREE
extern kvs_rbtree_t global_rbtree;
#endif

#if ENABLE_HASH
extern kvs_hash_t global_hash;
#endif

extern int global_cmd_log_fd;

#include <errno.h>
int write_full(int fd, const void *buf, size_t len)
{
    const uint8_t *p = buf;

    while (len > 0) {
        ssize_t n = write(fd, p, len);
        if (n < 0) {
            if (errno == EINTR)
                continue;
            return -1;
        }
        p += n;
        len -= n;
    }
    return 0;
}

// 1 read n suc, 0 eof, -1 error
int read_full(int fd, void *buf, size_t n)
{
    uint8_t *p = (uint8_t *)buf;
    size_t got = 0;

    while (got < n) {
        ssize_t r = read(fd, p + got, n - got);
        if (r > 0) {
            got += (size_t)r;
            continue;
        }
        if (r == 0) {
            return (got == 0) ? 0 : -1;
        }
        /* r < 0 */
        if (errno == EINTR) {
            continue;
        }
        return -1;
    }

    return 1;
}

// 0 suc, -1 err
int kvs_need(const uint8_t *p, const uint8_t *end, size_t n) {
	return (p + n <= end) ? 0 : -1;
}

// 注意u8类型不需要ntoh或者hton
// 0 suc, -1 err
int kvs_read_u8(const uint8_t **pp, const uint8_t *end, uint8_t *out) {
	const uint8_t *p = *pp;
	if (kvs_need(p, end, 1) < 0) return -1;
	*out = *p;
	*pp = p + 1;
	return 0;
}

int kvs_read_u16(const uint8_t **pp, const uint8_t *end, uint16_t *out) {
	const uint8_t *p = *pp;
	if (kvs_need(p, end, 2) < 0) return -1;
	uint16_t v;
	memcpy(&v, p, 2);
	*out = ntohs(v);
	*pp = p + 2;
	return 0;
}

int kvs_read_u32(const uint8_t **pp, const uint8_t *end, uint32_t *out) {
	const uint8_t *p = *pp;
	if (kvs_need(p, end, 4) < 0) return -1;
	uint32_t v;
	memcpy(&v, p, 4);
	*out = ntohl(v);
	*pp = p + 4;
	return 0;
}

int kvs_write_u8(uint8_t **pp, const uint8_t *end, uint8_t v) {
	uint8_t *p = *pp;
	if (kvs_need(p, end, 1) < 0) return -1;
	*p = v;
	*pp = p + 1;
	return 0;
}

int kvs_write_u16(uint8_t **pp, const uint8_t *end, uint16_t v) {
	uint8_t *p = *pp;
	if (kvs_need(p, end, 2) < 0) return -1;
	uint16_t be = htons(v);
	memcpy(p, &be, 2);
	*pp = p + 2;
	return 0;
}

int kvs_write_u32(uint8_t **pp, const uint8_t *end, uint32_t v) {
	uint8_t *p = *pp;
	if (kvs_need(p, end, 4) < 0) return -1;
	uint32_t be = htonl(v);
	memcpy(p, &be, 4);
	*pp = p + 4;
	return 0;
}

// -1 err, 0 suc
int kvs_write_file(FILE *fp, const void *buf, size_t n) {
    const uint8_t *p = (const uint8_t *)buf;
    while (n > 0) {
        size_t w = fwrite(p, 1, n, fp);
        if (w == 0) return -1;
        p += w;
        n -= w;
    }
    return 0;
}

// -1 err, 0 suc
int kvs_read_file(FILE *fp, void *buf, size_t n){
	uint8_t *p = (uint8_t *)buf;
    while (n > 0) {
        size_t r = fread(p, 1, n, fp);
        if (r == 0) return -1; // EOF or error
        p += r;
        n -= r;
    }
    return 0;
}