#ifndef INVITE_LINK_C_H
#define INVITE_LINK_C_H

#include <stdint.h>
#include <stddef.h>

#define INVITE_LINK_VERSION     0x03
#define INVITE_PUBKEY_SIZE      32
#define INVITE_ADDR_MAX         32
#define INVITE_PASS_MAX         128
#define INVITE_SNAME_MAX        64

#define INVITE_PROTO_UDP        0x01
#define INVITE_PROTO_TCP        0x02
#define INVITE_PROTO_REALITY    0x04   /* флаг reality-камуфляжа поверх TCP (reality-TCP = 0x06) */

#ifdef __cplusplus
extern "C" {
#endif

struct InviteAddrC {
    int      family;
    uint8_t  address[16];
    uint8_t  socketId;
    uint8_t  proto;
    uint16_t port;
};

/* Reality-параметры узла (node-global: одинаковы для всех reality-сокетов). */
struct InviteRealityC {
    uint8_t  has;
    uint8_t  short_id[8];
    uint8_t  server_pubkey[32];
    uint8_t  version[3];
    char     server_name[INVITE_SNAME_MAX];
};

struct InviteDataC {
    uint64_t channelId;
    uint64_t join_key;          /* 64-битный ключ входа (генерируется инвайтером) */
    uint8_t  pubkey[INVITE_PUBKEY_SIZE];
    uint64_t nodeId;
    uint8_t  addrCount;
    struct   InviteAddrC addrs[INVITE_ADDR_MAX];
    char     password[INVITE_PASS_MAX];   /* empty = no password (v1 compat) */
    uint8_t  password_len;
    struct   InviteRealityC reality;
};

/* decode utun://base64 link string, returns 0 on success, -1 on error.
   error buffer must be at least 256 bytes */
int invite_link_decode(const char* link, size_t link_len, struct InviteDataC* out,
                       char* error_buf, size_t error_buf_size);

/* encode invite data to utun://base64 string.
   password may be NULL (v1 format, no password).
   out buffer must be large enough (~512 bytes safe).
   returns written length (excluding null), or -1 on error */
int invite_link_encode(const struct InviteDataC* data, const char* password, char* out, size_t out_size);

/* serialize per-addr format for chat_sync_connect_from_invite():
   family(1) + socketId(1) + proto(1) + address(4|16) + port(2 BE)
   returns total bytes written, or -1 if buf too small */
int invite_serialize_addrs(const struct InviteDataC* data, uint8_t* buf, size_t buf_size);

#ifdef __cplusplus
}
#endif
#endif /* INVITE_LINK_C_H */