/* metainfo.h — .torrent and magnet parsing (v1 / v2 / hybrid).
 *
 * The info-hash is computed over the *raw* bytes of the `info` dictionary as
 * they appear in the file (bencode preserves that span), never by re-encoding:
 *   v1 info-hash = SHA-1  (info-bytes)
 *   v2 info-hash = SHA-256(info-bytes)
 * A hybrid torrent carries both and so joins both the v1 and v2 swarms.
 *
 * Phase 2 parses v1 fully (name, piece length, file list, the 20-byte piece
 * hash table) and computes the v2 info-hash + version for hybrid/v2 files; the
 * full v2 file-tree / piece-layer plumbing is wired in Phase 3 (storage).
 */
#ifndef NAUT_METAINFO_H
#define NAUT_METAINFO_H

#include "naut/common.h"
#include "naut/hash.h"

typedef struct {
    char   *path;     /* '/'-joined, NUL-terminated */
    int64_t length;
} naut_file;

typedef struct naut_metainfo {
    bool    has_v1, has_v2;
    uint8_t infohash_v1[NAUT_SHA1_LEN];
    uint8_t infohash_v2[NAUT_SHA256_LEN];

    char   *name;
    int64_t piece_length;
    int64_t total_length;

    /* v1 piece hash table: num_pieces * 20 bytes (owned copy) */
    uint32_t       num_pieces;
    const uint8_t *piece_hashes;

    naut_file *files;     size_t num_files;
    char     **trackers;  size_t num_trackers;   /* announce + announce-list, flattened */

    /* internals kept alive so piece_hashes/name stay valid */
    void *_owned;
} naut_metainfo;

naut_err naut_metainfo_parse(const uint8_t *data, size_t len, naut_metainfo *out);
/* Parse a raw bencoded info dictionary obtained through BEP-9. Optional
 * tracker URLs are copied into the resulting metainfo. */
naut_err naut_metainfo_parse_info(const uint8_t *info, size_t info_len,
                                  const char *const *trackers,
                                  size_t num_trackers,
                                  naut_metainfo *out);
void     naut_metainfo_free(naut_metainfo *mi);

/* hex of the v1 info-hash (41 bytes incl NUL) — for logging/RPC. */
void naut_infohash_v1_hex(const naut_metainfo *mi, char out[41]);

/* --- magnet links -------------------------------------------------------- */
typedef struct {
    bool    has_v1, has_v2;
    uint8_t infohash_v1[NAUT_SHA1_LEN];
    uint8_t infohash_v2[NAUT_SHA256_LEN];
    char   *name;                              /* dn (display name), may be NULL */
    char  **trackers; size_t num_trackers;     /* tr= params */
} naut_magnet;

naut_err naut_magnet_parse(const char *uri, naut_magnet *out);
void     naut_magnet_free(naut_magnet *m);

#endif /* NAUT_METAINFO_H */