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

set -e

os="$(uname -o 2>/dev/null || true)"
base="$(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

# 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
else
	tbase=""
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

# Used by git-annex assistant to further install itself.
GIT_ANNEX_APP_BASE="$base"
export GIT_ANNEX_APP_BASE

# Put our binaries first, to avoid issues with out of date or incompatible
# 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

# LD_PRELOAD may interact badly with the bundled libc and other libraries,
# which may have a different subarchitecture than the preloaded library.
unset LD_PRELOAD

# Avoid using system locales, which may interact badly with bundled libc.
ORIG_LOCPATH="$LOCPATH"
export ORIG_LOCPATH
LOCPATH="$HOME/.cache/git-annex/locales/$(echo "$base" | tr / _ )"
export LOCPATH

# Clean up locale caches when their standalone bundle no longer exists.
for localecache in $HOME/.cache/git-annex/locales/*; do
	cachebase=$(cat "$localecache/base" 2>/dev/null || true)
	if [ ! -d "$cachebase" ] || ! cmp "$localecache/buildid" "$cachebase/buildid" >/dev/null ; then
		rm -rf "$localecache" 2>&1 || true
	fi
done

# If the locale cache for this bundle is out of date, refresh it.
if [ -e "$LOCPATH/buildid" ] && ! cmp "$LOCPATH/buildid" "$base/buildid" >/dev/null ; then
	rm -rf "$LOCPATH"
fi
if ! mkdir -p "$LOCPATH"; then
	echo "Unable to write to $LOCPATH; can't continue!" >&2
	exit 1
fi
echo "$base" > "$LOCPATH/base"
cp "$base/buildid" "$LOCPATH/buildid"

# Generate locale definition files for the locales in use,
# using the localedef and locale files from the bundle.
# Currently only utf-8 locales are handled.
lastlocaleenv=""
for localeenv in "$LANG" "$LANGUAGE" "$LC_CTYPE" "$LC_NUMERIC" "$LC_TIME" \
		"$LC_COLLATE" "$LC_MONETARY" "$LC_MESSAGES" "$LC_PAPER" \
		"$LC_NAME" "$LC_ADDRESS" "$LC_TELEPHONE" "$LC_MEASUREMENT" \
		"$LC_IDENTIFICATION" "$LC_ALL"; do
	if [ "$localeenv" != "$lastlocaleenv" ]; then
		lastlocaleenv="$localeenv"
		if [ ! -d "$LOCPATH/$localeenv" ]; then
			if [ "${localeenv##[!.]*.}" = "utf8" ] || [ "${localeenv##[!.]*.}" = "UTF-8" ]; then
				(
					rm -rf "$LOCPATH/$localeenv.new.$$" &&
					mkdir -p "$LOCPATH/$localeenv.new.$$" &&
					# cd to $base since localedef reads files from pwd
					cd "$base" &&
					# Run localedef using the bundled i18n files;
					# use LANG=C to avoid it reading the system locale archive.
					I18NPATH="$base/i18n" LANG=C localedef -i "${localeenv%%.*}" -c -f UTF-8 "$LOCPATH/$localeenv.new.$$" &&
					mv "$LOCPATH/$localeenv.new.$$" "$LOCPATH/$localeenv"
				) >/dev/null 2>/dev/null || true
			fi
		fi
	fi
done

useproot=""
case "$os" in
	# Make this bundle work well on Android.
	Android)
		if [ -e "$base/git" ]; then
			echo "Running on Android.. Adding git-annex to PATH for you, and tuning for optimal behavior." >&2
			# The bundled git does not work well on sdcard, so delete
			# it and use termux's git which works better.
			cd "$base"
			find . | grep git | grep -v git-annex | grep -v git-remote-tor-annex | grep -v git-remote-gcrypt | xargs rm -rf
			cd "$orig"
			# Save the poor Android user the typing.
			if ! [ -e "$HOME/.profile" ] || ! grep -q "$base" "$HOME/.profile"; then
				echo 'PATH=$PATH:'"$base" >> $HOME/.profile
			fi
		fi
		
		# Work around Android 8's seccomp filtering of some crucial
		# system calls, using termux's version of proot.
		useproot=1
		
		# Store ssh connection caching sockets outside of sdcard.
		GIT_ANNEX_TMP_DIR="$TMPDIR"
		export GIT_ANNEX_TMP_DIR

		GIT_ANNEX_STANDLONE_ENV="PATH GCONV_PATH MANPATH LOCPATH"
		export GIT_ANNEX_STANDLONE_ENV
		;;
	*)
		# 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 LOCPATH"
		export GIT_ANNEX_STANDLONE_ENV
		;;
esac

if [ "$1" ]; then
	cmd="$1"
	shift 1
else
	cmd=sh
fi

if [ -z "$tbase" ]; then
	if [ "$useproot" ]; then
		exec proot "$cmd" "$@"
	else
		exec "$cmd" "$@"
	fi
else
	# allow EXIT trap to cleanup
	if [ "$useproot" ]; then
		proot "$cmd" "$@"
	else
		"$cmd" "$@"
	fi
fi
