#ifndef COUNTERPART_ENV_NAME
#define COUNTERPART_ENV_NAME "GIT_SSH_FETCH"
#endif
#ifndef COUNTERPART_PROGRAM_NAME
#define COUNTERPART_PROGRAM_NAME "git-ssh-fetch"
#endif
#ifndef MY_PROGRAM_NAME
#define MY_PROGRAM_NAME "git-ssh-upload"
#endif

#include "cache.h"
#include "rsh.h"
#include "refs.h"

#include <string.h>

static unsigned char local_version = 1;
static unsigned char remote_version = 0;

static int verbose = 0;

static int serve_object(int fd_in, int fd_out) {
	ssize_t size;
	unsigned char sha1[20];
	signed char remote;
	int posn = 0;
	do {
		size = read(fd_in, sha1 + posn, 20 - posn);
		if (size < 0) {
			perror("git-ssh-upload: read ");
			return -1;
		}
		if (!size)
			return -1;
		posn += size;
	} while (posn < 20);
	
	if (verbose)
		fprintf(stderr, "Serving %s\n", sha1_to_hex(sha1));

	remote = 0;
	
	if (!has_sha1_file(sha1)) {
		fprintf(stderr, "git-ssh-upload: could not find %s\n",
			sha1_to_hex(sha1));
		remote = -1;
	}
	
	write(fd_out, &remote, 1);
	
	if (remote < 0)
		return 0;
	
	return write_sha1_to_fd(fd_out, sha1);
}

static int serve_version(int fd_in, int fd_out)
{
	if (read(fd_in, &remote_version, 1) < 1)
		return -1;
	write(fd_out, &local_version, 1);
	return 0;
}

static int serve_ref(int fd_in, int fd_out)
{
	char ref[PATH_MAX];
	unsigned char sha1[20];
	int posn = 0;
	signed char remote = 0;
	do {
		if (read(fd_in, ref + posn, 1) < 1)
			return -1;
		posn++;
	} while (ref[posn - 1]);

	if (verbose)
		fprintf(stderr, "Serving %s\n", ref);

	if (get_ref_sha1(ref, sha1))
		remote = -1;
	write(fd_out, &remote, 1);
	if (remote)
		return 0;
	write(fd_out, sha1, 20);
        return 0;
}


static void service(int fd_in, int fd_out) {
	char type;
	int retval;
	do {
		retval = read(fd_in, &type, 1);
		if (retval < 1) {
			if (retval < 0)
				perror("git-ssh-upload: read ");
			return;
		}
		if (type == 'v' && serve_version(fd_in, fd_out))
			return;
		if (type == 'o' && serve_object(fd_in, fd_out))
			return;
		if (type == 'r' && serve_ref(fd_in, fd_out))
			return;
	} while (1);
}

static const char ssh_push_usage[] =
	MY_PROGRAM_NAME " [-c] [-t] [-a] [-w ref] commit-id url";

int main(int argc, char **argv)
{
	int arg = 1;
        char *commit_id;
        char *url;
	int fd_in, fd_out;
	const char *prog;
	unsigned char sha1[20];
	char hex[41];

	prog = getenv(COUNTERPART_ENV_NAME);
	if (!prog) prog = COUNTERPART_PROGRAM_NAME;
	while (arg < argc && argv[arg][0] == '-') {
		if (argv[arg][1] == 'w')
			arg++;
                arg++;
        }
	if (argc < arg + 2)
		usage(ssh_push_usage);
	commit_id = argv[arg];
	url = argv[arg + 1];
	if (get_sha1(commit_id, sha1))
		usage(ssh_push_usage);
	memcpy(hex, sha1_to_hex(sha1), sizeof(hex));
	argv[arg] = hex;

	if (setup_connection(&fd_in, &fd_out, prog, url, arg, argv + 1))
		return 1;

	service(fd_in, fd_out);
	return 0;
}