#!/bin/bash

TEMPLATE_DIR="templates"

TMP_DIR_PREFIX="$(pwd)/tmp"
rm -rf "${TMP_DIR_PREFIX}"/* # ?? Could be vulnerable

if [ -z "${DISTRO_TC}" ]
then
	DISTRO_TC=x86_64-x221e-linux-gnu
fi

if [ -z "${CROSS_TC}" ]
then
	CROSS_TC=${HOME}/opt/cross
fi

if [ -z "${CC}" ]
then
	CC=x86_64-x221e-linux-gnu-gcc
fi

if [ -z "${MASTERDIR}" ]
then
	MASTERDIR="$(pwd)/bootstrap"
fi

mkdir -p "${MASTERDIR}"
touch "${MASTERDIR}/packages"

if [ -z "${CROSS_ENV_ROOT}" ]
then
	CROSS_ENV_ROOT="${HOME}/opt/cross/"
fi

MIRROR_GNU_FTP="https://ftp.gnu.org/gnu/"

function download_source {
	upstream="$1"
	out_name="$2"
	
	curl -L --output-dir=${TMP_DIR_PREFIX} "${upstream}" -o "${out_name}"
	
	if [ $? -ne 0 ]
	then
		echo -e "error: failed to download '${out_name}' from '${upstream}'"
	fi
}

function unpack_source {
	file="$1"

	currdir="$(pwd)"
	
	cd "${TMP_DIR_PREFIX}"

	if [[ ! -e "${file}" || ! -f "${file}" ]]
	then
		echo -e "error: unpack_source: file '${file}' does not exist."
		exit 1
	fi

	tar -xf "${file}"
	
	if [ $? -ne 0 ]
	then
		echo -e "error: unpack_source: tar failed with error code: ${?}"
	fi
	
	cd "${currdir}"
}

function handle_configure {
	pkg_dir="$1"

	if [[ "$(type -t 'do_configure')" == "function" ]]
	then
		if [[ ! -e "${pkg_dir}" || ! -d "${pkg_dir}" ]]
		then
			echo -e "error: pkg_install: could not find: '${pkg_dir}'"
			exit 1
		fi
		
		cd "${pkg_dir}"
		
		do_configure

		cd "${currdir}"
	fi	

}

function handle_build {
	pkg_dir="$1"

	if [[ "$(type -t 'do_build')" == "function" ]]
	then
		if [[ ! -e "${pkg_dir}" || ! -d "${pkg_dir}" ]]
		then
			echo -e "error: pkg_install: could not find: '${pkg_dir}'"
			exit 1
		fi
		
		cd "${pkg_dir}"

		do_build

		cd "${currdir}"
	fi

}

function handle_install {
	pkg_dir="$1"

	if [[ "$(type -t 'do_install')" == "function" ]]
	then
		if [[ ! -e "${pkg_dir}" || ! -d "${pkg_dir}" ]]
		then
			echo -e "error: pkg_install: could not find: '${pkg_dir}'"
			exit 1
		fi
		
		cd "${pkg_dir}"

		do_install	

		cd "${currdir}"
	fi
}

function pkg_install {
	pkg="$1"

	pkg_file="${TEMPLATE_DIR}/${pkg}/template"

	if [[ ! -e "${pkg_file}" || ! -f "${pkg_file}" ]]
	then
		echo -e "error: template '${pkg_file}' does not exist!"
		exit 1
	fi

	currdir=$(pwd)
	source "${pkg_file}"

	if [ "${#dependson[@]}" -gt 0 ]
	then
		for i in "${dependson[@]}"
		do
			if [[ "$(sed -n /${i}/p ${MASTERDIR}/packages)" != "$i" ]]
			then
				echo -e "'${i}' must be installed before you can install '${pkgname}'"
				exit 1
			fi
		done
	fi

	pkg_dir_name="${pkgname}-${version}"
	archive_name="${pkg_dir_name}.tar"

	download_source "${upstream}" "${archive_name}"
	unpack_source "${archive_name}"

	handle_configure "${TMP_DIR_PREFIX}/${pkg_dir_name}"
	handle_build "${TMP_DIR_PREFIX}/${pkg_dir_name}"
	handle_install "${TMP_DIR_PREFIX}/${pkg_dir_name}"

	echo "${pkgname}=${version}" >> "${MASTERDIR}/packages"
}

function bootstrap {
	for i in $(ls templates/)
	do
		pkg_install "${i}"
	done
}

function requirements {
	ncurses_lib_loc="${CROSS_TC}/usr/lib/libncursesw_g.a"
	echo -e "Checking the existence of ncursesw in the cross-toolchain environment."
	if [[ ! -e "${ncurses_lib_loc}" || ! -f "${ncurses_lib_loc}" ]]
	then
		MASTERDIR="${CROSS_TC}"		
		pkg_install "ncurses"
	fi
	echo -e "requirement met: ncurses"
}

case "$1" in
	"pkg") pkg_install "${@:2}" ;;
	"bootstrap") bootstrap "${@:2}" ;;
	"requirements") requirements "${@:2}" ;;
	*) echo -e "error: invalid command" &&  exit 1 ;;
esac