#!/bin/sh

main() {
    if [ $1 == "check_backup" ]; then
        check_backup
    elif [ $1 == "apply_backup" ]; then
        apply_backup
    fi
}

reverse_string() {
    local input="$1"
    local reverse=""

    local len=${#input}
    local i=$(($len-1))
    while [ $i -ge 0 ]; do
        reverse="$reverse${input:$i:1}"
        i=$((i-1))
    done

    echo "$reverse"
}

check_backup() {
    local size
    local write_new_config_ok='1'

    local this_device_code=$(uci -q get system.system.device_code)
    local this_device_code_len=${#this_device_code}

    local device_code_in_the_new_config=$(cat /tmp/new_config_dir/etc/config/system | grep device_code | cut -d ' ' -f3)
    device_code_in_the_new_config=${device_code_in_the_new_config:1}
    device_code_in_the_new_config=${device_code_in_the_new_config%?}
    local device_code_in_new_config_len=${#device_code_in_the_new_config}

    local this_device_name=${this_device_code:0:4}
    [ "$this_device_name" = "RUT2" ] && size=8 || size=7

    this_device_code=${this_device_code:0:$size}
    device_code_in_the_new_config=${device_code_in_the_new_config:0:$size}

    local this_device_fw_version=$(cat /etc/version)

    local fw_version_in_new_config=$(cat /tmp/new_config_dir/etc/config/system | grep device_fw_version | cut -d ' ' -f3)
    fw_version_in_new_config=${fw_version_in_new_config:1}
    fw_version_in_new_config=${fw_version_in_new_config%?}
    local fw_version_in_new_config_len=${#fw_version_in_new_config}

    this_device_fw_version=$(reverse_string $this_device_fw_version)
    this_device_fw_version=$(echo $this_device_fw_version | awk -F _ '{print $1}')
    this_device_fw_version=$(reverse_string $this_device_fw_version)

    fw_version_in_new_config=$(reverse_string $fw_version_in_new_config)
    fw_version_in_new_config=$(echo $fw_version_in_new_config | awk -F _ '{print $1}')
    fw_version_in_new_config=$(reverse_string $fw_version_in_new_config)

    if [ $this_device_code_len -ne 12 ] || [ $device_code_in_new_config_len -ne 12 ] || [ "$this_device_code" != "$device_code_in_the_new_config" ]; then
        write_new_config_ok='0'
    fi

    if [ $fw_version_in_new_config_len -lt 12 ] || [ $(expr ${this_device_fw_version} \< ${fw_version_in_new_config}) -eq 1 ]; then
        write_new_config_ok='0'
    fi

    echo "$write_new_config_ok"
}

apply_backup() {
    /etc/init.d/simcard reload >/dev/null 2>/dev/null
    rm /tmp/new_config_dir/etc/config/hwinfo /tmp/new_config_dir/etc/inittab 2>/dev/null
    sed -i "s/\/home\/root/\/root/" /tmp/new_config_dir/etc/passwd
    sed -i "s/\/bin\/sh/\/bin\/ash/" /tmp/new_config_dir/etc/passwd
    cp -rf /tmp/new_config_dir/etc/ / 2>/dev/null
    cp -r /rom/etc/uci-defaults/* /etc/uci-defaults/ 2>/dev/null
}

main $1

exit 0