/*
 * Copyright (C) 2009-2012 the libgit2 contributors
 *
 * This file is part of libgit2, distributed under the GNU GPL v2 with
 * a Linking Exception. For full terms see the included COPYING file.
 */
#ifndef INCLUDE_transport_h__
#define INCLUDE_transport_h__

#include "git2/net.h"
#include "git2/indexer.h"
#include "vector.h"
#include "posix.h"
#include "common.h"
#include "netops.h"
#ifdef GIT_SSL
# include <openssl/ssl.h>
# include <openssl/err.h>
#endif


#define GIT_CAP_OFS_DELTA "ofs-delta"
#define GIT_CAP_MULTI_ACK "multi_ack"
#define GIT_CAP_SIDE_BAND "side-band"
#define GIT_CAP_SIDE_BAND_64K "side-band-64k"
#define GIT_CAP_INCLUDE_TAG "include-tag"

typedef struct git_transport_caps {
	int common:1,
		ofs_delta:1,
		multi_ack: 1,
		side_band:1,
		side_band_64k:1,
		include_tag:1;
} git_transport_caps;

#ifdef GIT_SSL
typedef struct gitno_ssl {
	SSL_CTX *ctx;
	SSL *ssl;
} gitno_ssl;
#endif


/*
 * A day in the life of a network operation
 * ========================================
 *
 * The library gets told to ls-remote/push/fetch on/to/from some
 * remote. We look at the URL of the remote and fill the function
 * table with whatever is appropriate (the remote may be git over git,
 * ssh or http(s). It may even be an hg or svn repository, the library
 * at this level doesn't care, it just calls the helpers.
 *
 * The first call is to ->connect() which connects to the remote,
 * making use of the direction if necessary. This function must also
 * store the remote heads and any other information it needs.
 *
 * The next useful step is to call ->ls() to get the list of
 * references available to the remote. These references may have been
 * collected on connect, or we may build them now. For ls-remote,
 * nothing else is needed other than closing the connection.
 * Otherwise, the higher leves decide which objects we want to
 * have. ->send_have() is used to tell the other end what we have. If
 * we do need to download a pack, ->download_pack() is called.
 *
 * When we're done, we call ->close() to close the
 * connection. ->free() takes care of freeing all the resources.
 */

struct git_transport {
	/**
	 * Where the repo lives
	 */
	char *url;
	/**
	 * Whether we want to push or fetch
	 */
	int direction : 1, /* 0 fetch, 1 push */
		connected : 1,
		check_cert: 1,
		use_ssl : 1,
		own_logic: 1, /* transitional */
		rpc: 1; /* git-speak for the HTTP transport */
#ifdef GIT_SSL
	struct gitno_ssl ssl;
#endif
	git_vector refs;
	git_vector common;
	gitno_buffer buffer;
	GIT_SOCKET socket;
	git_transport_caps caps;
	void *cb_data;
	git_atomic cancel;

	/**
	 * Connect and store the remote heads
	 */
	int (*connect)(struct git_transport *transport, int dir);
	/**
	 * Send our side of a negotiation
	 */
	int (*negotiation_step)(struct git_transport *transport, void *data, size_t len);
	/**
	 * Push the changes over
	 */
	int (*push)(struct git_transport *transport);
	/**
	 * Negotiate the minimal amount of objects that need to be
	 * retrieved
	 */
	int (*negotiate_fetch)(struct git_transport *transport, git_repository *repo, const git_vector *wants);
	/**
	 * Download the packfile
	 */
	int (*download_pack)(struct git_transport *transport, git_repository *repo, git_off_t *bytes, git_indexer_stats *stats);
	/**
	 * Close the connection
	 */
	int (*close)(struct git_transport *transport);
	/**
	 * Free the associated resources
	 */
	void (*free)(struct git_transport *transport);
	/**
	 * Callbacks for the progress and error output
	 */
	void (*progress_cb)(const char *str, int len, void *data);
	void (*error_cb)(const char *str, int len, void *data);
};


int git_transport_new(struct git_transport **transport, const char *url);
int git_transport_local(struct git_transport **transport);
int git_transport_git(struct git_transport **transport);
int git_transport_http(struct git_transport **transport);
int git_transport_https(struct git_transport **transport);
int git_transport_dummy(struct git_transport **transport);

/**
  Returns true if the passed URL is valid (a URL with a Git supported scheme,
  or pointing to an existing path)
*/
int git_transport_valid_url(const char *url);

typedef int (*git_transport_cb)(git_transport **transport);

#endif
