#!/bin/sh
# Runs a shell command (or interactive shell) using the binaries and
# libraries bundled with this app.

set -e

base="$(dirname "$0")"

if [ ! -d "$base" ]; then
	echo "** cannot find base directory (I seem to be $0)" >&2
	exit 1
fi

if [ ! -e "$base/bin/git-annex" ]; then
	echo "** base directory $base does not contain bin/git-annex" >&2
	exit 1
fi
if [ ! -e "$base/bin/git" ]; then
	echo "** base directory $base does not contain bin/git" >&2
	exit 1
fi

# Get absolute path to base, to avoid breakage when things change directories.
orig="$(pwd)"
cd "$base"
base="$(pwd)"
cd "$orig"

# --library-path won't work if $base contains : or ;
# Detect this problem, and work around it by using a temp directory.
if echo "$base" | grep -q '[:;]'; then
	tbase=$(mktemp -d -p /tmp annexshimXXXXXXXXX 2>/dev/null || true)
	if [ -z "$tbase" ]; then
		tbase="/tmp/annexshim.$$"
		mkdir "$tbase"
	fi
	ln -s "$base" "$tbase/link"
	base="$tbase/link"
	cleanuptbase () {
		rm -rf "$tbase"
	}
	trap cleanuptbase EXIT
fi

# Set this variable when using this script inside a package of git-annex,
# which arranges for git-annex, git-annex-shell, and git to all be in the
# standard PATH.
GIT_ANNEX_PACKAGE_INSTALL=
if [ -z "$GIT_ANNEX_PACKAGE_INSTALL" ]; then
	# Install shim that's used to run git-annex-shell from ssh authorized
	# keys. The assistant also does this when run, but the user may not
	# be using the assistant.
	if [ ! -e "$HOME/.ssh/git-annex-shell" ]; then
		mkdir "$HOME/.ssh" >/dev/null 2>&1 || true
		if [ -e "$HOME/.ssh" ]; then
			(
				echo "#!/bin/sh"
				echo "set -e"
				echo "if [ \"x\$SSH_ORIGINAL_COMMAND\" != \"x\" ]; then"
				echo "exec '$base/runshell' git-annex-shell -c \"\$SSH_ORIGINAL_COMMAND\""
				echo "else"
				echo "exec '$base/runshell' git-annex-shell -c \"\$@\""
				echo "fi"
			) > "$HOME/.ssh/git-annex-shell"
			chmod +x "$HOME/.ssh/git-annex-shell"
		fi
	fi

	# And this shim is used by the webapp when adding a remote ssh server.
	if [ ! -e "$HOME/.ssh/git-annex-wrapper" ]; then
		mkdir "$HOME/.ssh" >/dev/null 2>&1 || true
		if [ -e "$HOME/.ssh" ]; then
			(
				echo "#!/bin/sh"
				echo "set -e"
				echo "exec '$base/runshell' \"\$@\""
			) > "$HOME/.ssh/git-annex-wrapper"
			chmod +x "$HOME/.ssh/git-annex-wrapper"
		fi
	fi
fi

# Put our binaries first, to avoid issues with out of date or incompatable
# system binaries. Extra binaries come after system path.
ORIG_PATH="$PATH"
export ORIG_PATH
PATH="$base/bin:$PATH:$base/extra"
export PATH

# These env vars are used by the shim wrapper around each binary.
for lib in $(cat "$base/libdirs"); do
	GIT_ANNEX_LD_LIBRARY_PATH="$base/$lib:$GIT_ANNEX_LD_LIBRARY_PATH"
done
export GIT_ANNEX_LD_LIBRARY_PATH
GIT_ANNEX_DIR="$base"
export GIT_ANNEX_DIR

ORIG_GCONV_PATH="$GCONV_PATH"
export ORIG_GCONV_PATH
GCONV_PATH="$base/$(cat "$base/gconvdir")"
export GCONV_PATH

ORIG_GIT_EXEC_PATH="$GIT_EXEC_PATH"
export ORIG_GIT_EXEC_PATH
GIT_EXEC_PATH="$base/git-core"
export GIT_EXEC_PATH

ORIG_GIT_TEMPLATE_DIR="$GIT_TEMPLATE_DIR"
export ORIG_GIT_TEMPLATE_DIR
GIT_TEMPLATE_DIR="$base/templates"
export GIT_TEMPLATE_DIR

ORIG_MANPATH="$MANPATH"
export ORIG_MANPATH
MANPATH="$base/usr/share/man:$MANPATH"
export MANPATH

# Indicate which variables were exported above and should be cleaned
# when running non-bundled programs.
GIT_ANNEX_STANDLONE_ENV="PATH GCONV_PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR MANPATH"
export GIT_ANNEX_STANDLONE_ENV

if [ "$1" ]; then
	cmd="$1"
	shift 1
	if [ -z "$tbase" ]; then
		exec "$cmd" "$@"
	else
		# allow EXIT trap to cleanup
		"$cmd" "$@"
	fi
else
	sh
fi
