#!/usr/bin/env bash

# Copyright (C) 2016 Paul Kocialkowski <contact@paulk.fr>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

GLOBIGNORE=".:.." # This enables the shell option 'dotglob' as well.
shopt -s nullglob extglob

libreboot_usage() {
	local action
	local target

	printf '%s\n' "${executable} [action] [target] [arguments]" >&2

	printf '\n%s\n' 'Generic project actions:' >&2

	for action in ${PROJECT_ACTIONS_GENERIC}; do
		printf '%s\n' "  ${action}" >&2
	done

	printf '\n%s\n' 'Virtual project actions:' >&2

	printf '%s\n' '  sources'
	printf '%s\n' '  produce'
	printf '%s\n' '  test'

	printf '\n%s\n' 'Project targets:' >&2

	for target in "${root}/${PROJECTS}"/*; do
		if project_check "${target}"; then
			printf '%s\n' "  ${target}" >&2
		fi
	done

	printf '\n%s\n' 'Generic tool actions:' >&2

	for action in ${TOOL_ACTIONS_GENERIC}; do
		printf '%s\n' "  ${action}" >&2
	done

	printf '\n%s\n' 'Tool targets:' >&2

	for target in "${root}/${TOOLS}"/*; do
		if tool_check "${target}"; then
			printf '%s\n' "  ${target}" >&2
		fi
	done

	printf '\n%s\n' 'Environment variables:' >&2
	printf '%s\n' '  PROJECTS_FORCE - Projects to always perform actions for' >&2
	printf '%s\n' '  TOOLS_FORCE - Tools to always perform actions for' >&2
	printf '%s\n' '  RELEASE_KEY - GPG key to use for release' >&2
	printf '%s\n' '  VBOOT_KEYS_PATH - Path to the vboot keys' >&2
	printf '%s\n' '  LIBFAKETIME_PATH - Path to the libfaketime shared library' >&2
	printf '%s\n' '  TASKS - Number of simultaneous tasks to run' >&2
	printf '%s\n' '  VERSION - Version string to use' >&2

	printf '\n%s\n' 'Configuration files:' >&2
	printf '%s\n' "  ${BUILD_SYSTEM}.conf - Environment variables configuration" >&2
}

libreboot_project() {
	action="$1"
	shift
	project="$1"
	shift

	case ${action} in
		"sources")
			(
				set +e

				project_action_arguments "extract" "${project}" "$@" && return 0
				project_action_arguments "download" "${project}" "$@" && return 0
			)
			;;
		"produce")
			for action in "build" "install" "release"; do
				project_action_arguments "${action}" "${project}" "$@"
			done
			;;
		"test")
			for action in ${PROJECT_ACTIONS}; do
				project_action_arguments "${action}" "${project}" "$@"
			done
			;;
		*)
			if ! project_function_check "${project}" "${action}"; then
				libreboot_usage
				exit 1
			elif [[ "${action}" == 'usage' ]]; then
				project_action "${action}" "${project}" "$@"
			else
				project_action_arguments "${action}" "${project}" "$@"
			fi
			;;
	esac
}

libreboot_tool() {
	action="$1"
	shift
	tool="$1"
	shift

	case ${action} in
		*)
			if ! tool_function_check "${tool}" "${action}"; then
				libreboot_usage
				exit 1
			fi

			if [[ "${action}" == "usage" ]]; then
				tool_action "${action}" "${tool}" "$@"
			else
				tool_action_arguments_recursive "${action}" "${tool}" "$@"
			fi
			;;
	esac
}

libreboot_setup() {
	root="$(readlink -f "$(dirname "$0")")"
	executable="$(basename "$0")"

	local requirements="git"
	local requirement_path

	libreboot_setup_include
	libreboot_setup_variables

	for requirement in ${requirements}; do
		requirement_path="$(which "${requirement}" || true)"

		if [[ -z "${requirement_path}" ]]; then
			printf '%s\n' "Missing requirement: ${requirement}" >&2
			exit 1
		fi
	done
}

libreboot_setup_include() {
	local libs_path="${root}/libs"
	local conf_path

	source "${libs_path}/project"
	source "${libs_path}/tool"
	source "${libs_path}/common"
	source "${libs_path}/git"

	conf_path="${root}/${BUILD_SYSTEM}.conf"

	if [[ -f "${conf_path}" ]]; then
		source "${conf_path}"
	fi
}

libreboot_setup_variables() {
	local vboot_tools_path="$(project_install_path 'vboot' 'tools')"
	local version_path="${root}/${DOTVERSION}"
	local epoch_path="${root}/${DOTEPOCH}"
	local rnd_seed_path="${root}/${DOTRNDSEED}"

	# Used by GCC, e.g., -frandom-seed="${RANDOM_SEED}"
	if [[ -z "${RANDOM_SEED}" ]]; then
		if [[ -f "${rnd_seed_path}" ]]; then
			RANDOM_SEED="$(cat "${rnd_seed_path}")"
		else
			RANDOM_SEED="${RANDOM}" # True randomness is unnecessary
		fi
	fi

	# Also used by GCC, but as an environment variable
	if [[ -z "${SOURCE_DATE_EPOCH}" ]]; then
		if git_check "${root}"; then
			SOURCE_DATE_EPOCH="$(git log -1 --format=%ct)"
		elif [[ -f "${epoch_path}" ]]; then
			SOURCE_DATE_EPOCH="$(cat "${epoch_path}")"
		else
			SOURCE_DATE_EPOCH="$(date +%s)"
		fi
	fi

	if [[ -z "${VERSION}" ]]; then
		if git_check "${root}"; then
			VERSION="${BUILD_SYSTEM}-$(git_describe "${root}" 2> /dev/null || echo 'git')"
		elif [[ -f "${version_path}" ]]; then
			VERSION="$(cat "${version_path}")"
		else
			VERSION="${BUILD_SYSTEM}"
		fi
	fi

	if [[ -d "${vboot_tools_path}/devkeys/" ]]; then
		VBOOT_KEYS_PATH="${VBOOT_KEYS_PATH:-${vboot_tools_path}/devkeys/}"
	fi

	CONFIG_SHELL="${CONFIG_SHELL:-$(which bash)}"
	EDITOR="${EDITOR:-$(which vi || true)}"
	TASKS="${TASKS:-1}"

	# Environment variables useful for creating reproducible builds
	if [[ -n "${LIBFAKETIME_PATH}" ]]; then
		BUILD_DATE_FMT="%Y-%m-%d %H:%M:%S"
		BUILD_DATE="$(date -u -d "@${SOURCE_DATE_EPOCH}" "+${BUILD_DATE_FMT}" 2>/dev/null || date -u -r "${SOURCE_DATE_EPOCH}" "+${BUILD_DATE_FMT}" 2>/dev/null || date -u "+${BUILD_DATE_FMT}")"
		FAKETIME="@${BUILD_DATE}"
		LC_ALL='C.UTF-8'
		LD_PRELOAD="${LIBFAKETIME_PATH}"
		TZ='UTC'
	fi
}

libreboot() {
	action="$1"
	shift
	target="$1"
	shift

	set -e

	libreboot_setup "$@"

	if [[ -z "${action}" ]] || [[ -z "${target}" ]]; then
		libreboot_usage
		exit 1
	fi

	requirements 'tar' 'sed' 'gpg' 'sha256sum' 'wget'

	if project_check "${target}"; then
		libreboot_project "${action}" "${target}" "$@"
	elif tool_check "${target}"; then
		libreboot_tool "${action}" "${target}" "$@"
	else
		libreboot_usage
		exit 1
	fi
}

libreboot "$@"