#!/bin/bash


# -----------------------------------------------------------------------------
#
# Copyright (c) 2016..2018 bwLehrpool-Projektteam
#
# This program/file is free software distributed under the GPL version 2.
# See https://www.gnu.org/licenses/old-licenses/gpl-2.0-standalone.html
#
# If you have any feedback please consult https://bwlehrpool.de and
# send your feedback to support@bwlehrpool.de.
#
# General information about bwLehrpool can be found at https://bwlehrpool.de
#
# -----------------------------------------------------------------------------
#
#				Mini-Linux Toolkit
#
# -----------------------------------------------------------------------------

declare -rg ARG0="$0"
declare -rg SELF="$(readlink -f "$ARG0")"
declare -rg ROOT_DIR="$(dirname "${SELF}")"
declare -rg MLTK_PID="$$"


# Make apt-get install non-interactive when it comes to postinstall questions
# ie. kdm asking which dm you want to set as default
export DEBIAN_FRONTEND=noninteractive

qnd_exit() {
	unset_quiet
	kill "$MLTK_PID"
	[ $# -ge 1 ] && kill "$1"
	exit 1
}

# Support sourcing a "config" where you can set up stuff like 'export http_proxy=...'
if [ -e "$ROOT_DIR/config" ]; then
	data1="$( mktemp )"
	data2="$( mktemp )"
	declare -p > "$data1"
	. "$ROOT_DIR/config"
	declare -p > "$data2"
fi

# source all helper unit files that are found under helper/*.inc
# or core/includes/*.inc
# a helper unit may contain a function called "__init" which will be called
# after all helpers have been sourced.
for HELPER in "$ROOT_DIR"/core/includes/helper/*.inc "$ROOT_DIR"/core/includes/*.inc; do
	SHORT=${HELPER%.inc}
	SHORT="_init_${SHORT##*/}"
	. <(sed "s/^__init/$SHORT/" "$HELPER") && continue
	unset_quiet
	echo "Could not source $HELPER"
	qnd_exit
done
# called below, after initial_checks
init_helpers () {
	# in case the helers have init functions, call them now
	for HELPER in "$ROOT_DIR"/helper/*.inc "$ROOT_DIR"/core/includes/*.inc; do
		SHORT=${HELPER%.inc}
		SHORT="_init_${SHORT##*/}"
		type -t "$SHORT" | grep -q '^function$' && "$SHORT"
	done
}

banner () {
	echo -e "\033[38;5;202m\t           __   __   __    "
	echo -e "\033[38;5;202m\t.--------.|  | |  |_|  |--."
	echo -e "\033[38;5;208m\t|        ||  |_|   _|    < "
	echo -e "\033[38;5;214m\t|__|__|__||____|____|__|__|"
	echo -e "\033[38;5;214m\t "
	echo -e "\033[38;5;220m\t                     ** OpenSLX Project // 2013..2016 **"
	echo -e "\033[38;5;226m\t                        http://lab.openslx.org/"
	echo -e "\033[00m"
}

print_usage() {
	echo -e ""
	echo -e "Toolkit for creating preboot mini-linux for OpenSLX NG (mltk)"
	echo -e "Usage: $ARG0 <target> [-d] [-c [module]*] [-b [module]*] [-n [name]]"
	echo -e ""
	echo -e "  Options:"
	echo -e "     -d            activates debug output for the task (spamy)"
	echo -e "     -b            build module(s) and copy them to the target build directory"
	echo -e "     -c            clean build directory of module(s) and target dir"
	echo -e "     -i            run in 'installer mode' for stage4 system"
	echo -e "     -n            bind mount all the local builds (var/builds) to /export/builds;"
	echo -e "                   the optional parameter name allows to change the default mount target"
	echo -e "                    <name> -> /export/<name>"
	echo -e ""
	echo -e "  You can pass names of specific modules to clean/build (-c / -b)."
	echo -e "  Otherwise, all modules will be cleaned/built."
	echo -e ""
	echo -e "  Examples:"
	echo -e "     $ARG0 stage31 -c -b"
	echo -e "          (clean and build all modules symlinked in core/targets/stage31)"
	echo -e "     $ARG0 stage32 -c base sshd -b sshd ldm -d"
	echo -e "          (clean base and sshd, build sshd and ldm, be verbose)"
	echo -e "     $ARG0 -n"
	echo -e "          (provides bind mount at /export/build for synchronizing)"
	echo -e ""
	echo -e "  Existing targets are:"
	echo -e "    $(echo $(ls "${ROOT_DIR}/core/targets" "${ROOT_DIR}/overlay/targets" 2>/dev/null || echo "No targets found."))"
	echo -e ""
}

check_devtools() {
	# Checking for needed development tools, compilers etc.
	# Required: m4 make gcc g++ binutils
	# no qmake here, qmake (libqt4-devel) should be installed in a module!
	local DEV_TOOLS="gcc g++ make cmake m4 strip git depmod patch pkg-config automake autoconf aclocal lsb_release strings wget rsync lsof diff cmp zstd" # 'strip' as marker for binutils

	# DEV_CHECK marks missing dev-tools
	local DEV_TOOLS_MISSING=""
	for i in $DEV_TOOLS; do
		which "$i" 2>/dev/null 1>&2 || DEV_TOOLS_MISSING+="$i "
	done

	if [ -n "$DEV_TOOLS_MISSING" ]; then
		pinfo "You appear to be missing following development tools."
		pinfo "Missing tools are: $DEV_TOOLS_MISSING"
		pinfo "For $SYS_DISTRIBUTION you probably need to run:"
		case $SYS_DISTRIBUTION in
			ubuntu | debian)
				pinfo "apt install build-essential m4 pkg-config cmake automake autoconf binutils lsb-release wget rsync diffutils lsof zstd"
				pinfo "to install missing development tools."
				;;
			# FIXME: Don't know how precise this filter works so we might want to have a better matching ...
			opensuse)
				pinfo "zypper install gcc gcc-c++ make m4 binutils git module-init-tools patch pkg-config cmake lsb-release wget rsync diffutils lsof zstd"
				pinfo "to install missing development tools."
				;;
			fedora | scientific | centos)
				pinfo "yum install redhat-lsb gcc-c++ gcc make m4 binutils pkgconfig patch cmake lsb-release wget rsync diffutils lsof zstd"
				;;
			*)
				perror "No installation help for $SYS_DISTRIBUTION available."
				;;
		esac
		perror "Please install missing dependencies (see above) and try again!"
	fi
}

initial_checks() {
	if [ "x$(whoami)" != "xroot" ]; then
		perror "ERROR: You need to have root rights to install packages and do various other things."
		exit 1
	else
		banner
	fi
}

read_params() {
	local list_name=

	# A target represents a set of modules to be build for a specific stage.
	# i.e. a very basic stage31 target should includes:
	#	- busybox
	#	- kernel
	#	- rootfs-stage31
	# a basic stage32 target could add:
	#	- systemd
	#	- dbus
	#	- pam
	# for a GUI, you could add:
	#	- xorg
	#	- kdm
	#	- plymouth
	TARGET=""
	if [[ "$1" != -* ]]; then
		TARGET="$1"
		shift
	elif [[ "$1" == "-h" || "$1" == "--help" ]]; then
		print_usage
		exit 1
	elif [[ "$1" != "-n" ]]; then
		perror "A target is required. None given."
	fi

	# handle rest of arguments
	while [ "$#" -gt "0" ]; do
		local PARAM="$1"
		shift

		# options to current target
		if [[ "$PARAM" == -* ]]; then
			case "$PARAM" in
				-c)
					list_name="REMOTE_LIST_CLEAN"
					MODE_CLEAN=1
					;;
				-b)
					list_name="REMOTE_LIST_BUILD"
					MODE_BUILD=1
					;;
				-d)
					MLTK_DEBUG=1
					continue
					;;
				-n)
					if [ -z "$1" ]; then
						REMOTE_EXPORT_DIR="/export/build"
					else
						REMOTE_EXPORT_DIR="/export/$1"
						shift
					fi
					MODE_EXPORT=1
					continue
					;;
				-i)
					MLTK_INSTALL=1
					continue
					;;
				--force-sys-version)
					if [ -z "$1" ]; then
						perror "--force-sys-version requires an argument, e.g. '18.04'."
					else
						FORCE_SYS_VERSION="$1"
						shift
					fi
					continue
					;;
				*)
					pwarning "Unknown flag to target: $PARAM"
					print_usage
					exit 1
					;;
			esac
			continue
		fi

		# module name
		if [ -z "$list_name" ]; then
			pwarning "Module name given, but no action specified (-b/-c)"
			print_usage
			exit 1
		fi
		declare -g "${list_name}=${!list_name} $PARAM"
	done

	# exit if no command
	if [ -z "$MODE_CLEAN" ] && [ -z "$MODE_BUILD" ] && [ -z "$MODE_EXPORT" ]; then
		pwarning "No action specified"
		print_usage
		exit 1
	fi
}

run() {
	if [ -n "$MLTK_DEBUG" ]; then
		unset_quiet
	else
		set_quiet
	fi
	. "${ROOT_DIR}/core/bin/setup_target"
	[ -n "$MODE_CLEAN" ] && clean_modules $TARGET $REMOTE_LIST_CLEAN
	[ -n "$MODE_BUILD" ] && generate_target $TARGET $REMOTE_LIST_BUILD
	[ -n "$MODE_EXPORT" ] && export_builds
}

unset MLTK_DISTCC MLTK_CCACHE MLTK_INSTALL MLTK_DEBUG MODE_CLEAN MODE_BUILD MODE_EXPORT
REMOTE_LIST_CLEAN=
REMOTE_LIST_BUILD=

initial_checks
read_params "$@"
init_helpers

if [ -n "$data1" ] && [ -n "$data2" ]; then
	pinfo "Applied local config:"
	while read -r line; do
		pinfo "$line"
	done < <( diff -U0 "$data1" "$data2" | grep -v -e '^+++ ' -e '^--- ' -e '^@@ ' -e ' BASH_' -e ' _="' )
	rm -f -- "$data1" "$data2"
	unset data1 data2
fi

check_devtools

run
exit 0