#!/usr/pkg/bin/bash
#
# Add new remote branch
# Copyright (c) Petr Baudis, 2005
#
# Takes the desired branch name and source location as parameters.
#
# This command lets you add to the list of 'remote branches'. Those are
# branches in your local repository which correspond to some branches
# in other repositories.
#
# After you add a remote branch, you can `cg-fetch` from it to get the
# latest changes on the branch, as they appeared in the remote repository.
#
# Terminology note: This command concerns remote branches, not the local
# ones (those managed by `cg-switch`).
#
# The possible source location specifiers are:
#
# 1. Local path - note that fetching will hardlink the objects if possible.
#
# 2. rsync - `rsync://host/path`
#    THE rsync REPOSITORY ACCESS METHOD IS DEPRECATED AND WILL BE REMOVED
#    IN THE FUTURE! The problem is that it will download _all_ data from
#    the remote repository, including objects which do not belong to the
#    one particular branch you want to fetch.
#
# 3. HTTP - `http://host/path`
#
# 4. HTTPS - `https://host/path`
#
# 5. FTP - 'ftp://host/path'
#
# 6. SSH - `git+ssh://host/path` or `host:path` (the latter can change);
#    note that the path must be absolute in the first case.
#
# 7. git daemon - `git://host/path`
#
#
# The URL can have a fragment part, which identifies a branch inside of
# the remote repository (in the form "repoURL#branchname"). Otherwise,
# Cogito defaults to whatever branch the repository's HEAD points to
# at the time of each fetch.
#
# FILES
# -----
# $GIT_DIR/branches/BRANCH_NAME::
#	Contains the source location of the remote branch.
#
# $GIT_DIR/refs/heads/BRANCH_NAME::
# 	Contains pointer to the latest commit in a branch. It can be more
#	conveniently retrieved using `cg-object-id BRANCH_NAME`.
#
# EXAMPLE USAGE
# -------------
# Let's say you have a repository at `git+ssh://host/path/repo.git` and you
# want to fetch its 'testing' branch to your local repository. In that case
# you can do
#
#	$ cg-branch-add repo-testing 'git+ssh://host/path/repo.git#testing'
#
# and refer to it as 'repo-testing' anytime later:
#
#	$ cg-fetch repo-testing
#
# For example you can check the changes in the `repo-testing` branch compared
# to your current branch:
#
#	$ cg-diff -r repo-testing

# Testsuite: Partial (used in many tests but a dedicated testsuite is missing)

USAGE="cg-branch-add BRANCH_NAME LOCATION"
_git_wc_unneeded=1

. "${COGITO_LIB:-/usr/pkg/lib/cogito/}"cg-Xlib || exit 1

name="${ARGS[0]}"
location="${ARGS[1]}"

([ -n "$name" ] && [ -n "$location" ] && ! [ -n "${ARGS[2]}" ]) || usage
git-check-ref-format "refs/heads/$name" || \
	die "name contains invalid characters"
if [ "$name" = "this" ] || [ "$name" = "HEAD" ]; then
	die "given branch name is reserved"
fi

mkdir -p "$_git/branches/$(dirname "$name")"
[ -s "$_git/branches/$name" ] && die "branch already exists"
[ -s "$_git/refs/heads/$name" ] && warn "branch head already exists"

if ! echo "$location" | /usr/bin/grep -q ":" ; then
	location=$(echo "$location" | sed -e "s#^[^/]#$(pwd)\/&#" | normpath)
fi

echo "$location" >"$_git/branches/$name"
