#ifndef TRANSPORT_H
#define TRANSPORT_H

#include "cache.h"
#include "run-command.h"
#include "remote.h"

struct string_list;

struct git_transport_options {
        unsigned thin : 1;
        unsigned keep : 1;
        unsigned followtags : 1;
        unsigned check_self_contained_and_connected : 1;
        unsigned self_contained_and_connected : 1;
        unsigned update_shallow : 1;
        unsigned deepen_relative : 1;
        int depth;
        const char *deepen_since;
        const struct string_list *deepen_not;
        const char *uploadpack;
        const char *receivepack;
        struct push_cas_option *cas;
};

enum transport_family {
        TRANSPORT_FAMILY_ALL = 0,
        TRANSPORT_FAMILY_IPV4,
        TRANSPORT_FAMILY_IPV6
};

struct transport {
        struct remote *remote;
        const char *url;
        void *data;
        const struct ref *remote_refs;

        /**
         * Indicates whether we already called get_refs_list(); set by
         * transport.c::transport_get_remote_refs().
         */
        unsigned got_remote_refs : 1;

        /*
         * Transports that call take-over destroys the data specific to
         * the transport type while doing so, and cannot be reused.
         */
        unsigned cannot_reuse : 1;

        /*
         * A hint from caller that it will be performing a clone, not
         * normal fetch. IOW the repository is guaranteed empty.
         */
        unsigned cloning : 1;

        /*
         * These strings will be passed to the {pre, post}-receive hook,
         * on the remote side, if both sides support the push options capability.
         */
        const struct string_list *push_options;

        /**
         * Returns 0 if successful, positive if the option is not
         * recognized or is inapplicable, and negative if the option
         * is applicable but the value is invalid.
         **/
        int (*set_option)(struct transport *connection, const char *name,
                          const char *value);

        /**
         * Returns a list of the remote side's refs. In order to allow
         * the transport to try to share connections, for_push is a
         * hint as to whether the ultimate operation is a push or a fetch.
         *
         * If the transport is able to determine the remote hash for
         * the ref without a huge amount of effort, it should store it
         * in the ref's old_sha1 field; otherwise it should be all 0.
         **/
        struct ref *(*get_refs_list)(struct transport *transport, int for_push);

        /**
         * Fetch the objects for the given refs. Note that this gets
         * an array, and should ignore the list structure.
         *
         * If the transport did not get hashes for refs in
         * get_refs_list(), it should set the old_sha1 fields in the
         * provided refs now.
         **/
        int (*fetch)(struct transport *transport, int refs_nr, struct ref **refs);

        /**
         * Push the objects and refs. Send the necessary objects, and
         * then, for any refs where peer_ref is set and
         * peer_ref->new_oid is different from old_oid, tell the
         * remote side to update each ref in the list from old_oid to
         * peer_ref->new_oid.
         *
         * Where possible, set the status for each ref appropriately.
         *
         * The transport must modify new_sha1 in the ref to the new
         * value if the remote accepted the change. Note that this
         * could be a different value from peer_ref->new_oid if the
         * process involved generating new commits.
         **/
        int (*push_refs)(struct transport *transport, struct ref *refs, int flags);
        int (*push)(struct transport *connection, int refspec_nr, const char **refspec, int flags);
        int (*connect)(struct transport *connection, const char *name,
                       const char *executable, int fd[2]);

        /** get_refs_list(), fetch(), and push_refs() can keep
         * resources (such as a connection) reserved for further
         * use. disconnect() releases these resources.
         **/
        int (*disconnect)(struct transport *connection);
        char *pack_lockfile;
        signed verbose : 3;
        /**
         * Transports should not set this directly, and should use this
         * value without having to check isatty(2), -q/--quiet
         * (transport->verbose < 0), etc. - checking has already been done
         * in transport_set_verbosity().
         **/
        unsigned progress : 1;
        /*
         * If transport is at least potentially smart, this points to
         * git_transport_options structure to use in case transport
         * actually turns out to be smart.
         */
        struct git_transport_options *smart_options;

        enum transport_family family;
};

#define TRANSPORT_PUSH_ALL                      (1<<0)
#define TRANSPORT_PUSH_FORCE                    (1<<1)
#define TRANSPORT_PUSH_DRY_RUN                  (1<<2)
#define TRANSPORT_PUSH_MIRROR                   (1<<3)
#define TRANSPORT_PUSH_PORCELAIN                (1<<4)
#define TRANSPORT_PUSH_SET_UPSTREAM             (1<<5)
#define TRANSPORT_RECURSE_SUBMODULES_CHECK      (1<<6)
#define TRANSPORT_PUSH_PRUNE                    (1<<7)
#define TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND  (1<<8)
#define TRANSPORT_PUSH_NO_HOOK                  (1<<9)
#define TRANSPORT_PUSH_FOLLOW_TAGS              (1<<10)
#define TRANSPORT_PUSH_CERT_ALWAYS              (1<<11)
#define TRANSPORT_PUSH_CERT_IF_ASKED            (1<<12)
#define TRANSPORT_PUSH_ATOMIC                   (1<<13)
#define TRANSPORT_PUSH_OPTIONS                  (1<<14)
#define TRANSPORT_RECURSE_SUBMODULES_ONLY       (1<<15)

extern int transport_summary_width(const struct ref *refs);

/* Returns a transport suitable for the url */
struct transport *transport_get(struct remote *, const char *);

/*
 * Check whether a transport is allowed by the environment.
 *
 * Type should generally be the URL scheme, as described in
 * Documentation/git.txt
 *
 * from_user specifies if the transport was given by the user.  If unknown pass
 * a -1 to read from the environment to determine if the transport was given by
 * the user.
 *
 */
int is_transport_allowed(const char *type, int from_user);

/*
 * Check whether a transport is allowed by the environment,
 * and die otherwise.
 */
void transport_check_allowed(const char *type);

/* Transport options which apply to git:// and scp-style URLs */

/* The program to use on the remote side to send a pack */
#define TRANS_OPT_UPLOADPACK "uploadpack"

/* The program to use on the remote side to receive a pack */
#define TRANS_OPT_RECEIVEPACK "receivepack"

/* Transfer the data as a thin pack if not null */
#define TRANS_OPT_THIN "thin"

/* Check the current value of the remote ref */
#define TRANS_OPT_CAS "cas"

/* Keep the pack that was transferred if not null */
#define TRANS_OPT_KEEP "keep"

/* Limit the depth of the fetch if not null */
#define TRANS_OPT_DEPTH "depth"

/* Limit the depth of the fetch based on time if not null */
#define TRANS_OPT_DEEPEN_SINCE "deepen-since"

/* Limit the depth of the fetch based on revs if not null */
#define TRANS_OPT_DEEPEN_NOT "deepen-not"

/* Limit the deepen of the fetch if not null */
#define TRANS_OPT_DEEPEN_RELATIVE "deepen-relative"

/* Aggressively fetch annotated tags if possible */
#define TRANS_OPT_FOLLOWTAGS "followtags"

/* Accept refs that may update .git/shallow without --depth */
#define TRANS_OPT_UPDATE_SHALLOW "updateshallow"

/* Send push certificates */
#define TRANS_OPT_PUSH_CERT "pushcert"

/**
 * Returns 0 if the option was used, non-zero otherwise. Prints a
 * message to stderr if the option is not used.
 **/
int transport_set_option(struct transport *transport, const char *name,
                         const char *value);
void transport_set_verbosity(struct transport *transport, int verbosity,
        int force_progress);

#define REJECT_NON_FF_HEAD     0x01
#define REJECT_NON_FF_OTHER    0x02
#define REJECT_ALREADY_EXISTS  0x04
#define REJECT_FETCH_FIRST     0x08
#define REJECT_NEEDS_FORCE     0x10

int transport_push(struct transport *connection,
                   int refspec_nr, const char **refspec, int flags,
                   unsigned int * reject_reasons);

const struct ref *transport_get_remote_refs(struct transport *transport);

int transport_fetch_refs(struct transport *transport, struct ref *refs);
void transport_unlock_pack(struct transport *transport);
int transport_disconnect(struct transport *transport);
char *transport_anonymize_url(const char *url);
void transport_take_over(struct transport *transport,
                         struct child_process *child);

int transport_connect(struct transport *transport, const char *name,
                      const char *exec, int fd[2]);

/* Transport methods defined outside transport.c */
int transport_helper_init(struct transport *transport, const char *name);
int bidirectional_transfer_loop(int input, int output);

/* common methods used by transport.c and builtin/send-pack.c */
void transport_verify_remote_names(int nr_heads, const char **heads);

void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose);

int transport_refs_pushed(struct ref *ref);

void transport_print_push_status(const char *dest, struct ref *refs,
                  int verbose, int porcelain, unsigned int *reject_reasons);

typedef void alternate_ref_fn(const struct ref *, void *);
extern void for_each_alternate_ref(alternate_ref_fn, void *);
#endif