#!/usr/bin/perl
use strict;
use warnings;

use lib $ENV{GL_LIBDIR};
use Gitolite::Easy;

=for usage
Usage:    ssh git@host newbranch <repo name> <new branch name> <based-on ref name>

Create a new branch and set it to existing branch or tag.  You should have
write access to that branch.

NOTE: runs "git branch arg-2 arg-3" in repo given by arg-1, which means you
should NOT prefix arguments with "refs/heads/" or "refs/tags/".

----

This is for people who have restrictions on what files they can "touch".  When
you fork a branch and change a file, even if you changed only the files you're
allowed to, gitolite thinks you changed *all* the files in the repo because
the "old SHA" is basically empty.

This helps get around that by first creating the new branch, so that you can
then push to it.

To enable this command, add it to the rc file as a 'command'.

TODO: handle deletes also (less commonly encountered and left as an "exercise
for the reader" for now!)
=cut

usage() if not @ARGV or @ARGV < 3 or $ARGV[0] eq '-h';

my $repo   = shift;
my $newbr  = shift;
my $oldref = shift;

_die "you are not authorized" unless can_write($repo, "W", "refs/heads/$newbr");

Gitolite::Common::_system("git", "branch", $newbr, $oldref);