#!/bin/sh
# SPDX-License-Identifier: GPL-2.0-only
#
# Copyright (C) 2022-2025 ImmortalWrt.org

NAME="homeproxy"

RESOURCES_DIR="/etc/$NAME/resources"
mkdir -p "$RESOURCES_DIR"

RUN_DIR="/var/run/$NAME"
LOG_PATH="$RUN_DIR/$NAME.log"
mkdir -p "$RUN_DIR"

log() {
	echo -e "$(date "+%Y-%m-%d %H:%M:%S") $*" >> "$LOG_PATH"
}

to_upper() {
	echo -e "$1" | tr "[a-z]" "[A-Z]"
}

check_list_update() {
	local listtype="$1"
	local listrepo="$2"
	local listref="$3"
	local listname="$4"
	local lock="$RUN_DIR/update_resources-$listtype.lock"
	local github_token="$(uci -q get homeproxy.config.github_token)"
	local wget="wget --timeout=10 -q"

	exec 200>"$lock"
	if ! flock -n 200 &> "/dev/null"; then
		log "[$(to_upper "$listtype")] A task is already running."
		return 2
	fi

	local github_header_file=""
	if [ -n "$github_token" ]; then
		github_header_file="$RUN_DIR/.gh_header_${listtype}"
		( umask 077; printf 'Authorization: Bearer %s\n' "$github_token" > "$github_header_file" )
		trap "[ -n \"$github_header_file\" ] && rm -f \"$github_header_file\"" EXIT INT TERM
	fi

	local list_info="$($wget ${github_header_file:+--header-file=$github_header_file} -O- "https://api.github.com/repos/$listrepo/commits?sha=$listref&path=$listname&per_page=1")"
	local wget_exit=$?

	[ -n "$github_header_file" ] && rm -f "$github_header_file"
	trap - EXIT INT TERM

	if [ $wget_exit -ne 0 ]; then
		log "[$(to_upper "$listtype")] Failed to fetch version info (wget exit $wget_exit)."
		return 1
	fi
	local list_sha="$(echo -e "$list_info" | jsonfilter -qe "@[0].sha")"
	local list_date="$(echo -e "$list_info" | jsonfilter -qe "@[0].commit.committer.date" | cut -d 'T' -f1)"
	if [ -z "$list_sha" ]; then
		log "[$(to_upper "$listtype")] Failed to get the latest version, please retry later."
		return 1
	fi
	local list_ver="${list_date:+$list_date }$list_sha"

	local local_list_ver="$(cat "$RESOURCES_DIR/$listtype.ver" 2>"/dev/null" || echo "NOT_FOUND")"
	local local_list_sha="${local_list_ver##* }"
	local local_list_disp="${local_list_ver%% *}"
	if [ "$local_list_sha" = "$list_sha" ]; then
		[ "$local_list_ver" = "$local_list_sha" ] && [ -n "$list_date" ] && \
			echo -e "$list_ver" > "$RESOURCES_DIR/$listtype.ver"
		log "[$(to_upper "$listtype")] Current version: ${list_ver%% *}."
		log "[$(to_upper "$listtype")] You're already at the latest version."
		return 3
	else
		log "[$(to_upper "$listtype")] Local version: $local_list_disp, latest version: ${list_ver%% *}."
	fi

	if ! $wget "https://fastly.jsdelivr.net/gh/$listrepo@$list_sha/$listname" -O "$RUN_DIR/$listname" || [ ! -s "$RUN_DIR/$listname" ]; then
		rm -f "$RUN_DIR/$listname"
		log "[$(to_upper "$listtype")] Download failed."
		return 1
	fi

	if mv -f "$RUN_DIR/$listname" "$RESOURCES_DIR/$listtype.${listname##*.}"; then
		echo -e "$list_ver" > "$RESOURCES_DIR/$listtype.ver"
		log "[$(to_upper "$listtype")] Successfully updated."
	else
		rm -f "$RUN_DIR/$listname"
		log "[$(to_upper "$listtype")] Failed to install update (mv failed)."
		return 1
	fi

	return 0
}

case "$1" in
"china_ip4")
	check_list_update "$1" "1715173329/IPCIDR-CHINA" "master" "ipv4.txt"
	;;
"china_ip6")
	check_list_update "$1" "1715173329/IPCIDR-CHINA" "master" "ipv6.txt"
	;;
"gfw_list")
	check_list_update "$1" "Loyalsoldier/v2ray-rules-dat" "release" "gfw.txt"
	;;
"china_list")
	check_list_update "$1" "Loyalsoldier/v2ray-rules-dat" "release" "direct-list.txt" && \
		sed -i -e "s/full://g" -e "/:/d" "$RESOURCES_DIR/china_list.txt"
	;;
*)
	echo -e "Usage: $0 <china_ip4 / china_ip6 / gfw_list / china_list>"
	exit 1
	;;
esac