#!/usr/bin/env sh

##########
# Custom servercow.de DNS API v1 for use with [acme.sh](https://github.com/Neilpang/acme.sh)
#
# Usage:
# export SERVERCOW_API_Username=username
# export SERVERCOW_API_Password=password
# acme.sh --issue -d example.com --dns dns_servercow
#
# Issues:
# Any issues / questions / suggestions can be posted here:
# https://github.com/jhartlep/servercow-dns-api/issues
#
# Author: Jens Hartlep
##########

SERVERCOW_API="https://api.servercow.de/dns/v1/domains"

# Usage dns_servercow_add _acme-challenge.www.domain.com "abcdefghijklmnopqrstuvwxyz"
dns_servercow_add() {
	fulldomain=$1
	txtvalue=$2

	_info "Using servercow"
	_debug fulldomain "$fulldomain"
	_debug txtvalue "$txtvalue"

	SERVERCOW_API_Username="${SERVERCOW_API_Username:-$(_readaccountconf_mutable SERVERCOW_API_Username)}"
	SERVERCOW_API_Password="${SERVERCOW_API_Password:-$(_readaccountconf_mutable SERVERCOW_API_Password)}"
	if [ -z "$SERVERCOW_API_Username" ] || [ -z "$SERVERCOW_API_Password" ]; then
		SERVERCOW_API_Username=""
		SERVERCOW_API_Password=""
		_err "You don't specify servercow api username and password yet."
		_err "Please create your username and password and try again."
		return 1
	fi

	# save the credentials to the account conf file
	_saveaccountconf_mutable SERVERCOW_API_Username "$SERVERCOW_API_Username"
	_saveaccountconf_mutable SERVERCOW_API_Password "$SERVERCOW_API_Password"

	_debug "First detect the root zone"
	if ! _get_root "$fulldomain"; then
		_err "invalid domain"
		return 1
	fi

	_debug _sub_domain "$_sub_domain"
	_debug _domain "$_domain"

	if _servercow_api POST "$_domain" "{\"type\":\"TXT\",\"name\":\"$fulldomain\",\"content\":\"$txtvalue\",\"ttl\":20}"; then
		if printf -- "%s" "$response" | grep "ok" > /dev/null; then
			_info "Added, OK"
			return 0
		else
			_err "add txt record error."
			return 1
		fi
	fi
	_err "add txt record error."

	return 1
}

# Usage fulldomain txtvalue
# Remove the txt record after validation
dns_servercow_rm() {
	fulldomain=$1
	txtvalue=$2

	_info "Using servercow"
	_debug fulldomain "$fulldomain"
	_debug txtvalue "$fulldomain"

	SERVERCOW_API_Username="${SERVERCOW_API_Username:-$(_readaccountconf_mutable SERVERCOW_API_Username)}"
	SERVERCOW_API_Password="${SERVERCOW_API_Password:-$(_readaccountconf_mutable SERVERCOW_API_Password)}"
	if [ -z "$SERVERCOW_API_Username" ] || [ -z "$SERVERCOW_API_Password" ]; then
                SERVERCOW_API_Username=""
                SERVERCOW_API_Password=""
                _err "You don't specify servercow api username and password yet."
                _err "Please create your username and password and try again."
                return 1
        fi

	_debug "First detect the root zone"
	if ! _get_root "$fulldomain"; then
		_err "invalid domain"
		return 1
	fi

	_debug _sub_domain "$_sub_domain"
	_debug _domain "$_domain"

	if _servercow_api DELETE "$_domain"  "{\"type\":\"TXT\",\"name\":\"$fulldomain\"}"; then
		if printf -- "%s" "$response" | grep "ok" > /dev/null; then
			_info "Deleted, OK"
			_contains "$response" '"message":"ok"'
		else
			_err "delete txt record error."
			return 1
		fi
	fi

}

####################  Private functions below ##################################

# _acme-challenge.www.domain.com
# returns
#  _sub_domain=_acme-challenge.www
#  _domain=domain.com
_get_root() {
	fulldomain=$1
	i=2
	p=1

	while true; do
		_domain=$(printf "%s" "$fulldomain" | cut -d . -f $i-100)

		_debug _domain "$_domain"
		if [ -z "$_domain" ]; then
			# not valid
			return 1
		fi

		if ! _servercow_api GET "$_domain"; then
			return 1
		fi

		if ! _contains "$response" '"error":"no such domain in user context"' > /dev/null; then
			_sub_domain=$(printf "%s" "$fulldomain" | cut -d . -f 1-$p)
			if [ -z "$_sub_domain" ]; then
				# not valid
				return 1
			fi

			return 0
		fi

		p=$i
		i=$(_math "$i" + 1)
	done;

	return 1
}

_servercow_api() {
	method=$1
	domain=$2
	data="$3"

	export _H1="Content-Type: application/json"
	export _H2="X-Auth-Username: $SERVERCOW_API_Username"
	export _H3="X-Auth-Password: $SERVERCOW_API_Password"

	if [ "$method" != "GET" ]; then
		_debug data "$data"
		response="$(_post "$data" "$SERVERCOW_API/$domain" "" "$method")"
	else
		response="$(_get "$SERVERCOW_API/$domain")"
	fi

	if [ "$?" != "0" ]; then
		_err "error $domain"
		return 1
	fi
	_debug2 response "$response"
	return 0
}