#!/system/bin/sh
# This is run by the Android app, and runs a shell in an environment
# configured for git-annex.

set -e

prep () {
	# I'm installed as lib/lib.runshell.so
	orig="$(pwd)"
	cd "$0/../.."
	base="$(pwd)"

	# Cannot rely on Android providing a sane HOME
	HOME="/sdcard/git-annex.home"
	export HOME
}

buildtree () {
	echo "Installation starting to $base"
	cat "$base/lib/lib.version.so"

	if [ -e "$base/bin" ]; then
		mv "$base/bin" "$base/bin.old"
	fi
	mkdir -p "$base/bin"

	for prog in busybox git-annex git-shell git-upload-pack git gpg rsync ssh ssh-keygen; do
		echo "installing $prog"
		if [ -e "$base/bin/$prog" ]; then
			rm "$base/bin/$prog"
		fi
		ln "$base/lib/lib.$prog.so" "$base/bin/$prog"
	done

	$base/bin/busybox --install $base/bin

	$base/bin/rm -rf "$base/bin.old"

	cd "$base"
	$base/bin/tar zxf $base/lib/lib.git.tar.gz.so
	for prog in git git-shell git-upload-pack; do
		for link in $(cat "$base/links/$prog"); do
			echo "linking $link to $prog"
			if [ -e "$base/$link" ]; then
				rm "$base/$link"
			fi
			ln "$base/bin/$prog" "$base/$link"
		done
		rm "$base/links/$prog"
	done

	mkdir -p "$base/templates"
	mkdir -p "$base/tmp"

	cat "$base/lib/lib.version.so" > "$base/installed-version"
	echo "Installation complete"
}

install () {
	if [ ! -d "$base/bin" ]; then
		if ! mkdir -p "$HOME"; then
			echo "mkdir of $HOME failed!"
		fi
		if ! buildtree > $HOME/git-annex-install.log 2>&1; then
			echo "Installation failed! Please report a bug and attach $HOME/git-annex-install.log"
			sh
		fi
	elif [ ! -e "$base/installed-version" ] || ! cmp "$base/installed-version" "$base/lib/lib.version.so" >/dev/null; then
		if ! buildtree > $HOME/git-annex-install.log 2>&1; then
			echo "Upgrade failed! Please report a bug and attach $HOME/git-annex-install.log"
		fi
	fi
}

run () {
	# As good a start point as any.
	cd "$HOME"

	PATH="$base/bin:$PATH"
	export PATH
	
	ORIG_GIT_EXEC_PATH="$GIT_EXEC_PATH"
	export ORIG_GIT_EXEC_PATH
	GIT_EXEC_PATH=$base/libexec/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
	
	# Indicate which variables were exported above.
	GIT_ANNEX_STANDLONE_ENV="GIT_EXEC_PATH GIT_TEMPLATE_DIR"
	export GIT_ANNEX_STANDLONE_ENV
	
	# This is a temporary directory on a non-crippled filesystem.
	# This needs to be as short a path as possible.
	GIT_ANNEX_TMP_DIR=$base/tmp
	export GIT_ANNEX_TMP_DIR
	
	if [ "$1" ]; then
		cmd="$1"
		shift 1
		exec "$cmd" "$@"
	else
		sh
	fi
}

if ! prep; then
	echo "prep failed. Please report a bug."
	read line
fi
if ! install; then
	echo "install failed. Please report a bug."
	read line
fi
run