#!/bin/sh

#
# config
#

#
# usage
#

usage() { echo "
USAGE
	conf COMMAND FILE [command-options]

COMMAND
	modify <file> <parameter statement>
		if parameter is found modify its value
		uncomment parameter if needed
		Examples:
		conf modify /etc/clamav/clamd.conf Foreground yes
		conf modify /etc/amavisd.conf \$sa_tag_level_deflt = -999;

	replace <file> <old-string> <new-string>
		match <old-string> and relpace it with <new-string>
		Examples:
		conf replace /etc/amavisd.conf /var/run/clamav/clamd.sock /run/clamav/clamd.sock

	uncommentsection <file> <string>
		Remove all leading '#' starting with a line that matches <string> and
		ending with an empty line
		Examples:
		conf uncommentsection /etc/amavisd.conf '# ### http://www.clamav.net/'

	comment <file> <string>
		Add leading '#' to line matching <string>
		Examples:
		conf comment /etc/clamav/freshclam.conf UpdateLogFile

	addafter <file> <start-string> <add-string> [<stop-string>]
		Add <add-string> after line matching <start-string> folowed by an empty line or a line matching <stop-string>
		Examples:
		conf addafter /etc/amavisd.conf '@local_domains_maps' '$inet_socket_bind = '\''127.0.0.1'\'';'

	fixmissing <file> <source> [<source>]
		If <file> is missing create it using the first found <source>
 		Examples:
		conf fixmissing /etc/php/7.?/apache2/conf.d/kopano.ini /etc/php/7.?/mods-available/kopano.ini /etc/php5/conf.d/kopano.ini
FILE
	full path to file which will be edited in place
"
}

#
# commands
#

_escape() { echo "$@" | sed 's|/|\\\/|g' | sed 's|\$|\\\$|g' | sed "s/""'""/\\\x27/g" ;}
_exglob() { echo $(ls -d $(dirname $1))/$(basename $1) ;}

modify() {
	local cfg_file=$1
	shift
	local lhs="$1"
	shift
	local eq=
	local rhs=
	if [ "$1" = "=" ]; then
		eq="$1"
		shift
		rhs="$(_escape $@)"
	else
		rhs="$(_escape $@)"
	fi
	echo 's/.*('"$lhs"'\s*'"$eq"'\s*)[^ ]+(.*)/\1'"$rhs"'\2/g' $cfg_file
	sed -ri 's/.*('"$lhs"'\s*'"$eq"'\s*)[^ ]+(.*)/\1'"$rhs"'\2/g' $cfg_file
}

replace() {
	local cfg_file=$1
	local old="$(_escape $2)"
	local new="$(_escape $3)"
	echo 's/'"$old"'/'"$new"'/g' $cfg_file
	sed -i 's/'"$old"'/'"$new"'/g' $cfg_file
}

addafter() {
	local cfg_file=$1
	local start="$(_escape $2)"
	local new="$(_escape $3)"
	local stop="$(_escape $4)"
	if [ -z "$stop" ]; then
		echo '/'"$start"'/!{p;d;}; $!N;s/\n\s*$/\n'"$new"'\n/g' $cfg_file
		sed -i '/'"$start"'/!{p;d;}; $!N;s/\n\s*$/\n'"$new"'\n/g' $cfg_file
	else
		echo '/'"$start"'/!{p;d;}; $!N;s/\n(.*'"$stop"'.*)/\n'"$new"'\n\1/g' $cfg_file
		sed -ri '/'"$start"'/!{p;d;}; $!N;s/\n(.*'"$stop"'.*)/\n'"$new"'\n\1/g' $cfg_file
	fi

}

comment() {
	local cfg_file=$1
	local string="$2"
	sed -i 's/^'"$string"'/s/^/#/g' $cfg_file
}

uncommentsection() {
	local cfg_file=$1
	local startline="$(_escape $2)"
	echo '/^'"$startline"'$/,/^\s*$/s/^#*//g' $cfg_file
	sed -i '/^'"$startline"'$/,/^\s*$/s/^#*//g' $cfg_file
}

fixmissing() {
	local cfg_file=$(_exglob $1)
	shift
	if [ ! -e $cfg_file ]; then
		for src_file in $@; do
			echo "CHECKING:$src_file"
			if [ -e $(_exglob $src_file) ]; then
				echo "FOUND:$(_exglob $src_file)"
				ln -s $(_exglob $src_file) $cfg_file
				break
			fi
		done
	fi
}

cli_and_exit() {
	if [ "$(basename $0)" = conf ]; then
		local cmd=$1
		if [ -n "$cmd" ]; then
			shift
			echo CMD:$cmd ARG:"$@"
			$cmd "$@"
		else
			usage
		fi
		exit 0
	fi
}

#
# allow command line interface
#

cli_and_exit "$@"