#!/usr/bin/env sh
# This file is part of bearssl-sys. It is subject to the license terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/bearssl-sys/master/COPYRIGHT. No part of bearssl-sys, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
# Copyright © 2016 The developers of bearssl-sys. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/bearssl-sys/master/COPYRIGHT.


set -e
set -u
set -f


_program_path_find()
{
    if [ "${_program_fattening_program_path+set}" = 'set' ]; then
        printf '%s\n' "$_program_fattening_program_path"

    elif [ "${0%/*}" = "$0" ]; then

        # We've been invoked by the interpreter as, say, bash program
        if [ -r "$0" ]; then
            pwd -P
        # Clutching at straws; probably run via a download, anonymous script, etc, weird execve, etc
        else
            printf '\n'
        fi

    else

        # We've been invoked with a relative or absolute path (also when invoked via PATH in a shell)

        _program_path_find_parentPath()
        {
            parentPath="${scriptPath%/*}"
            if [ -z "$parentPath" ]; then
                parentPath='/'
            fi
            cd "$parentPath" 1>/dev/null
        }

        # pdksh / mksh have problems with unsetting a variable that was never set...
        if [ "${CDPATH+set}" = 'set' ]; then
            unset CDPATH
        fi

        if command -v realpath 1>/dev/null 2>/dev/null; then
            (
                scriptPath="$(realpath "$0")"

                _program_path_find_parentPath
                pwd -P
            )
        elif command -v readlink 1>/dev/null 2>/dev/null; then
            (
                scriptPath="$0"

                while [ -L "$scriptPath" ]
                do
                    _program_path_find_parentPath
                    scriptPath="$(readlink "$scriptPath")"
                done

                _program_path_find_parentPath
                pwd -P
            )
        else
            # This approach will fail in corner cases where the script itself is a symlink in a path not parallel with the concrete script
            (
                scriptPath="$0"

                _program_path_find_parentPath
                pwd -P
            )
        fi

    fi
}

compile_bearssl_fail()
{
	local message="$1"

	printf 'compile-bearssl:FAIL:%s\n' "$message" 1>&2
	exit 1
}

compile_bearssl_ensureRequiredBinariesArePresent()
{
	local reason="$1"
	shift 1

	local binary
	local missing=false
	for binary in "$@"
	do
		if ! command -v "$binary" 1>/dev/null 2>/dev/null; then
			printf 'compile-bearssl:%s\n' "The binary '$binary' needs to be in the path" 1>&2
			missing=true
		fi
	done

	if $missing; then
		compile_bearssl_fail "Please make sure that the missing binaries are installed because '$reason'"
	fi
}

_compile_bearssl_prepareForMacOSX_brewInstall()
{
	compile_bearssl_ensureRequiredBinariesArePresent brew

	local packageName="$1"
	if ! brew ls --versions "$packageName" 1>/dev/null 2>/dev/null; then
		brew install "$packageName" 1>&2
	fi
}

compile_bearssl_prepareForMacOSX()
{
	_compile_bearssl_prepareForMacOSX_brewInstall gnu-sed
	_compile_bearssl_prepareForMacOSX_brewInstall make
	_compile_bearssl_prepareForMacOSX_brewInstall libelf
	_compile_bearssl_prepareForMacOSX_brewInstall coreutils
	_compile_bearssl_prepareForMacOSX_brewInstall FiloSottile/musl-cross/musl-cross
}

compile_bearssl_parseCommandLine()
{
	case "$#" in

		0)
			:
		;;

		1)
			case "$1" in

				-h|--help)
					printf './compile-bearssl\n'
					printf './compile-bearssl -h|--help\n'
					printf 'Pass the environment variable NUM_JOBS to control the number of make jobs\n'
					exit 0
				;;

				*)
					compile_bearssl_fail "Does not take any arguments"
				;;

			esac
		;;

		*)
			compile_bearssl_fail "Does not take any arguments"
		;;

	esac
}

compile_bearssl_findFolderPaths()
{
	programFolderPath="$(_program_path_find)"

	cd "$programFolderPath"/.. 1>/dev/null 2>/dev/null
		homeFolderPath="$(pwd)"
	cd - 1>/dev/null 2>/dev/null

	configurationFolderPath="$homeFolderPath"/bindgen-wrapper.conf.d
}

compile_bearssl_platformSpecificPreparation()
{
	compile_bearssl_ensureRequiredBinariesArePresent uname
	platform="$(uname)"

	if [ -z "${NUM_JOBS+undefined}" ]; then
		numberOfMakeJobs=0
	else
		numberOfMakeJobs="$NUM_JOBS"
	fi

	case "$platform" in

		Darwin)
			compile_bearssl_prepareForMacOSX

			compile_bearssl_ensureRequiredBinariesArePresent brew

			export PATH="$(brew --prefix coreutils)"/libexec/gnubin:"$(brew --prefix gnu-sed)"/libexec/gnubin:"$PATH"

			muslIncludeFolderPath="$(brew --prefix musl-cross)"/libexec/x86_64-linux-musl/include

			if [ $numberOfMakeJobs -eq 0 ]; then
				compile_bearssl_ensureRequiredBinariesArePresent sysctl
				numberOfMakeJobs="$(sysctl -n hw.ncpu)"
			fi

		;;

		Linux)
			compile_bearssl_ensureRequiredBinariesArePresent make sed x86_64-linux-musl-gcc x86_64-linux-musl-ar rm mkdir rsync cat
			muslIncludeFolderPath='/usr/include'

			if [ $numberOfMakeJobs -eq 0 ]; then
				compile_bearssl_ensureRequiredBinariesArePresent grep
				numberOfMakeJobs="$(grep -c '^processor' /proc/cpuinfo)"
			fi
		;;

		*)
			compile_bearssl_fail "Only Darwin (Mac OS X) and Linux (specifically, Alpine Linux) are supported at this time"
		;;

	esac
}

compile_bearssl_createTemporaryFolder()
{
	temporaryFolderPath="$configurationFolderPath"/temporary
	rm -rf "$temporaryFolderPath"
	mkdir -m 0700 -p "$temporaryFolderPath"
}

compile_bearssl_makeCopyToAlter()
{
	rsync --archive --quiet --exclude=.git "$homeFolderPath"/lib/BearSSL/ "$temporaryFolderPath"/
}

compile_bearssl_installConfiguration()
{
	cp "$configurationFolderPath"/CrossCompileOnMacOsXConfiguration.mk "$temporaryFolderPath"/conf
}

compile_bearssl_make()
{
	cd "$temporaryFolderPath" 1>/dev/null 2>/dev/null
		make CONF=CrossCompileOnMacOsXConfiguration 1>&2
	cd - 1>/dev/null 2>/dev/null
	
	mkdir -m 0700 -p "$temporaryFolderPath"/root/usr/include
	rsync --archive --quiet "$temporaryFolderPath"/inc/ "$temporaryFolderPath"/root/usr/include/
	
	mkdir -m 0700 -p "$temporaryFolderPath"/root/usr/lib
	cp "$temporaryFolderPath"/build/libbearssl.a "$temporaryFolderPath"/root/usr/lib
}

compile_bearssl_main()
{
	compile_bearssl_parseCommandLine "$@"

	local programFolderPath
	local homeFolderPath
	local configurationFolderPath
	compile_bearssl_findFolderPaths

	local platform
	local muslIncludeFolderPath
	local numberOfMakeJobs
	compile_bearssl_platformSpecificPreparation

	local temporaryFolderPath
	compile_bearssl_createTemporaryFolder
	
	compile_bearssl_makeCopyToAlter
	
	compile_bearssl_installConfiguration
	
	compile_bearssl_make
	
	printf '\n\n\nFINISHED\n\n\n' 1>&2
}

compile_bearssl_main "$@"