#!/bin/bash
set -e -u

show_help() {
	echo 'Usage: pkg command [arguments]'
	echo ''
	echo 'A tool for managing packages. Commands:'
	echo ''
	echo '  files <packages>'
	echo '  install <packages>'
	echo '  list-all'
	echo '  list-installed'
	echo '  reinstall <packages>'
	echo '  search <query>'
	echo '  show <packages>'
	echo '  uninstall <packages>'
	echo '  upgrade'
	exit 1
}

select_mirror() {
	local main_repo="https://termux.org/packages"
	local top_mirrors="https://dl.bintray.com/termux/termux-packages-24 https://termux.mentality.rip/termux-packages-24 https://grimler.se/termux-packages-24 https://main.termux-mirror.ml"

	local current_mirror
	current_mirror=$(grep -P "^\s*deb\s+" @TERMUX_PREFIX@/etc/apt/sources.list | grep -oP 'https?://[a-z0-9/._-]+')

	# Do not update mirror if:
	# * Uses .cn domain - specific to Chinese users.
	# * If $TERMUX_PKG_NO_MIRROR_SELECT was set.
	if [ -n "${TERMUX_PKG_NO_MIRROR_SELECT-}" ] || grep -qP '.+\.cn/' <(echo "${current_mirror-x}"); then
		return
	fi

	if [ -n "$(find /data/data/com.termux/cache/apt/pkgcache.bin -mmin -180 2>/dev/null)" ]; then
		# Mirrors are rotated if either they are not working or 180 minutes timeout
		# has passed.
		if [ -n "${current_mirror}" ] && curl --user-agent 'Termux-PKG/1.0 mirror-checker' --head --fail --location "${current_mirror}/dists/stable/Release" >/dev/null 2>&1; then
			echo "Reusing mirror: ${current_mirror}"
			return
		fi
	fi

	# Shuffle mirrors and pick the first one which is accessible.
	local m selected_mirror=""
	for m in $(echo "$top_mirrors" | tr ' ' '\n' | shuf); do
		echo "Trying mirror: $m"
		if curl --user-agent 'Termux-PKG/1.0 mirror-checker' --head --fail --location "${m}/dists/stable/Release" >/dev/null 2>&1; then
			selected_mirror="$m"
			break
		fi
	done

	if [ -n "${selected_mirror}" ]; then
		echo "deb ${selected_mirror}/ stable main" > @TERMUX_PREFIX@/etc/apt/sources.list
	else
		echo "Using fallback mirror: ${main_repo}"
		echo "deb ${main_repo}/ stable main" > @TERMUX_PREFIX@/etc/apt/sources.list
	fi
}

update_apt_cache() {
	if [ -z "$(find /data/data/com.termux/cache/apt/pkgcache.bin -mmin -5 2>/dev/null)" ]; then
		apt update
	fi
}

if [ $# = 0 ]; then
	show_help
fi

CMD="$1"
shift 1

case "$CMD" in
	f*) dpkg -L "$@";;
	h*) show_help;;
	add|i*)
		select_mirror
		update_apt_cache
		apt install "$@"
		;;
	cl*) apt clean;;
	list-a*) apt list "$@";;
	list-i*) apt list --installed "$@";;
	rei*) apt install --reinstall "$@";;
	se*)
		select_mirror
		update_apt_cache
		apt search "$@"
		;;
	sh*) apt show "$@";;
	un*|rem*|rm|del*) apt remove "$@";;
	up*)
		select_mirror
		apt update
		apt full-upgrade "$@"
		;;
	*) echo "Unknown command: '$CMD' (run 'pkg help' for usage information)"; exit 1;;
esac