#!/bin/bash
# shellcheck disable=SC2250
#
# ax-make: Alex' Simple Makefile System
# Copyright (c)2014-2023 Alexander Barton (alex@barton.de)
#
# 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 2 of the License, or
# (at your option) any later version.
#

NAME=$(basename "$0")

Usage() {
	echo "Usage: $NAME [-2|-3|-l <lic>] [<lib-dir>]"
	echo
	echo "  -0           Don't create AUTHORS, COPYING and README files."
	echo '  -2           Use the GNU GPLv2 for the COPYING file.'
	echo '  -3           Use the GNU GPLv3 for the COPYING file.'
	echo '  -l <lic>     Specify license to use for the COPYING file:'
	echo '               <lic> can be "gpl2", "gpl3", "lgpl21", "lgpl3".'
	echo '               By default an empty COPYING file is created.'
	echo '  -m           Use Markdown, create AUTHORS.md and README.md.'
	echo
	echo "  <lib-dir>    Library directory. Default: current working directory."
	echo
	exit 2
}

Download() {
	URL="$1"
	FILE="$2"

	echo "Downloading $URL to \"$FILE\" ..."

	if curl --version >/dev/null 2>&1; then
		curl -#Lo "$FILE" "$URL" && return 0
		echo "Failed to download $URL! [curl]"
		return 1
	fi

	if wget --version >/dev/null 2>&1; then
		wget -qO "$FILE" --show-progress "$URL" && return 0
		echo "Failed to download $URL! [wget]"
		return 1
	fi

	echo "Can't download $URL, no download tool found!"
	return 1
}

LIB_D="."
LICENSE=""
ADD_FILES=1
unset SUFFIX

while true; do
	case "$1" in
		"-0")
			unset ADD_FILES
			;;
		"-2")
			LICENSE="gpl2"
			;;
		"-3")
			LICENSE="gpl3"
			;;
		"-l")
			LICENSE="$2"
			shift
			;;
		"-m")
			SUFFIX=".md"
			;;
		"-"*)
			Usage
			;;
		*)
			break
			;;
	esac
	shift
done

[[ $# -gt 1 ]] && Usage

[[ -n "$1" ]] && LIB_D="$1"

if [[ -r "/usr/local/share/ax-make/Makefile.ax" ]]; then
	MAKEFILE_AX="/usr/local/share/ax-make/Makefile.ax"
elif [[ -r "/usr/share/ax-make/Makefile.ax" ]]; then
	MAKEFILE_AX="/usr/share/ax-make/Makefile.ax"
else
	echo "$NAME: No source \"Makefile.ax\" found!"
	echo "$NAME: Please check your installation of \"ax-make\" and try again."
	exit 1
fi

# -- Makefile.ax --

if [[ ! -d "$LIB_D" ]]; then
	mkdir -pv "$LIB_D" || exit 1
fi

target="$LIB_D/$(basename "$MAKEFILE_AX")"
if [[ ! -e "$target" || "$MAKEFILE_AX" -nt "$target" ]]; then
	echo "Updating \"$target\" ..."
	cp -v "$MAKEFILE_AX" "$target" || exit 1
else
	echo "Makefile \"$target\" is up to date."
fi

# -- Project Makefile's ---

if [[ ! -e "Makefile" ]]; then
echo "Creating \"Makefile\" ..."
[[ "$LIB_D" != "." ]] && subdirs="$LIB_D" || subdirs=""
cat >"Makefile" <<EOF
#
# Makefile
#

SOURCE_ROOT ?= \$(CURDIR)

SUBDIRS = $subdirs

include $LIB_D/Makefile.ax
EOF
fi

if [[ "$LIB_D" != "." && ! -e "$LIB_D/Makefile" ]]; then
echo "Creating \"$LIB_D/Makefile\" ..."
cat >"$LIB_D/Makefile" <<EOF
#
# Makefile
#

SOURCE_ROOT ?= \$(CURDIR)/..

include Makefile.ax
EOF
fi

# --- Standard project files ---

if [[ ! -e AUTHORS && -n "$ADD_FILES" ]]; then
	if git --version >/dev/null 2>&1; then
		echo "Creating \"AUTHORS$SUFFIX\" file ..."
		echo "$(git config user.name) <$(git config user.email)>" >>"AUTHORS$SUFFIX"
	fi
fi

if [[ ! -e COPYING ]]; then
	LICENSE_URL=""
	case "$LICENSE" in
		"")
			;;
		"gpl2")
			LICENSE_URL="https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt"
			;;
		"gpl3")
			LICENSE_URL="https://www.gnu.org/licenses/gpl-3.0.txt"
			;;
		"lgpl21")
			LICENSE_URL="https://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt"
			;;
		"lgpl3")
			LICENSE_URL="https://www.gnu.org/licenses/lgpl-3.0.txt"
			;;
		*)
			echo "Can't setup unknown \"$LICENSE\" license!"
			;;
	esac
	[[ -n "$LICENSE_URL" ]] && Download "$LICENSE_URL" COPYING
else
	[[ -n "$LICENSE" ]] && echo "COPYING file already exists, skipping."
fi

files=()

if [[ -n "$ADD_FILES" ]]; then
	files+=(COPYING)
	files+=("AUTHORS$SUFFIX" "README$SUFFIX")
fi

for f in "${files[@]}"; do
	if [[ ! -e "$f" ]]; then
		echo "Creating empty \"$f\" file ..."
		touch "$f"
	fi
done

exit 0