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

# 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. This also makes the system locales be used.
GIT_ANNEX_PACKAGE_INSTALL=

set -e

orig_IFS="${IFS}"
unset IFS

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

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.$$"
			chmod +x "$HOME/.ssh/git-annex-shell.$$"
			mv -f "$HOME/.ssh/git-annex-shell.$$" "$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.$$"
			chmod +x "$HOME/.ssh/git-annex-wrapper.$$"
			mv -f "$HOME/.ssh/git-annex-wrapper.$$" "$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.
# (But if LOCPATH is set, don't override it.
ORIG_LOCPATH="$LOCPATH"
export ORIG_LOCPATH
if [ -z "${LOCPATH+set}" ] && [ -z "$GIT_ANNEX_PACKAGE_INSTALL" ]; then
	LOCPATH="$HOME/.cache/git-annex/locales/$(cat "$base/buildid")_$(echo "$base" | tr / _ )"
	# try to generate a short version, if md5sum is available
	locpathmd5=$( (echo "$LOCPATH" | md5sum | cut -d ' ' -f 1 2>/dev/null) || true)
	if [ -n "$locpathmd5" ]; then
		LOCPATH="$HOME/.cache/git-annex/locales/$locpathmd5"
	fi
	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 2>&1 ; then
			rm -rf "$localecache" >/dev/null 2>&1 || true
		fi
	done
	
	if [ ! -d "$LOCPATH" ]; then
		if ! mkdir -p "$LOCPATH"; then
			echo "Unable to write to $LOCPATH; can't continue!" >&2
			exit 1
		fi
	fi
	if [ ! -e "$LOCPATH/base" ]; then
		echo "$base" > "$LOCPATH/base.$$"
		mv -f "$LOCPATH/base.$$" "$LOCPATH/base"
	fi
	# Not using cp to avoid using the one bundled with git-annex
	# before the environment is set up to run it.
	if [ ! -e "$LOCPATH/buildid" ]; then
		cat < "$base/buildid" > "$LOCPATH/buildid.$$"
		mv -f "$LOCPATH/buildid.$$" "$LOCPATH/buildid"
	fi

	# 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" "$LC_ALL"; do
		if [ -n "$localeenv" ] && [ "$localeenv" != "$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"
						# In a race, LOCPATH may get created by another process,
						# in which cache the mv above would put it here.
						rm -rf "$LOCPATH/$localeenv/$localeenv.new.$$"
					) >/dev/null 2>/dev/null || true
				fi
			fi
		fi
	done
fi

useproot=""
case "$os" in
	# Make this bundle work well on Android.
	Android)
		if [ -e "$base/git" ]; then
			echo "Running on Android.. 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 "$base"
			find . | grep git | grep -v git-annex | grep -v git-remote-tor-annex | grep -v git-remote-gcrypt | xargs rm -rf
			# Use termux's uname, which knows it's on android,
			# not the bundled one.
			rm -f bin/uname
			# Fix shell scripts to work when run inside proot.
			termux-fix-shebang bin/* runshell git-annex git-annex-shell git-annex-webapp 
			cd "$orig"
			# Save the poor Android user the typing.
			if echo "$SHELL" | grep -q '/bash'; then
				if ! [ -e "$HOME/.profile" ] || ! grep -q "$base" "$HOME/.profile"; then
					echo "Adding git-annex to PATH for you, in $HOME/.profile"
					echo 'PATH=$PATH:'"$base" >> $HOME/.profile
				fi
			else
				echo "To use git-annex, you will need to add $base to your shell's PATH."
			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_SSH_SOCKET_DIR="$TMPDIR"
		export GIT_ANNEX_SSH_SOCKET_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

LD_HWCAP_MASK=
export LD_HWCAP_MASK

if [ -n "${orig_IFS}" ]; then
	IFS="${orig_IFS}"
	export IFS
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