#!/bin/sh

FAILSTATUS=""
PKG_CONFIG=${PKG_CONFIG:-pkg-config}

check_cmd() {
	cmd=$1
	printf "Checking for command ${cmd}... "
    if command -v ${cmd} > /dev/null 2>&1 ; then
        echo "found"
    else
        echo "not found"
        return 1
    fi
    return 0
}

check_pkg() {
	pkgname=$1
	add_define=$2
	atleast_version=$3
	printf "Checking for package ${pkgname}... "
	if $PKG_CONFIG --silence-errors "${pkgname}" ; then
		echo "found"
		if [ -n "$atleast_version" ] ; then
			if ! $PKG_CONFIG --atleast-version=$atleast_version ${pkgname} ; then
				echo "at least ${pkgname} $atleast_version required."
				return 1
			fi
		fi
		echo "# configuration for package ${pkgname}" >> config.mk
		result=`$PKG_CONFIG --cflags ${pkgname}`
		if [ -n "$result" ] ; then
			echo "DEFINES+=$result" >> config.mk
		fi
		if [ -n "$add_define" ] ; then
			echo "DEFINES+=${add_define}" >> config.mk
		fi
		echo "LDFLAGS+=`$PKG_CONFIG --libs ${pkgname}`" >> config.mk
		echo "" >> config.mk
	else
		echo "not found"
		return 1
	fi
	return 0
}

check_custom() {
	pkgname=$1
	customconfig=$2
	add_define=$3
	printf "Checking for package ${pkgname} using ${customconfig}... "
	if ${customconfig} --cflags > /dev/null 2>&1 ; then
		echo "found"
		echo "# configuration for package ${pkgname}" >> config.mk
		result=`${customconfig} --cflags`
		if [ -n "$result" ] ; then
			echo "DEFINES+=${result}" >> config.mk
		fi
		if [ -n "$add_define" ] ; then
			echo "DEFINES+=${add_define}" >> config.mk
		fi
		echo "LDFLAGS+=`${customconfig} --libs`" >> config.mk
		echo "" >> config.mk
	else
		echo "not found"
		return 1
	fi
	return 0
}

fail() {
	pkgname=$1
	rm -f config.mk
	echo ""
	echo "You need package ${pkgname} in order to compile this program."
	echo "Please make sure it is installed."
	FAILSTATUS="1"
}

fail_custom() {
	err=$1
	rm -f config.mk
	echo ""
	echo "ERROR: ${err}"
	FAILSTATUS="1"
}

all_aboard_the_fail_boat() {
	if [ "x$FAILSTATUS" != "x" ] ; then
		rm -f config.mk
		echo ""
		echo "One or more required dependencies couldn't be found. Please install"
		echo "these packages and retry compilation."
		exit 1
	fi
}

check_ssl_implementation() {
	if curl-config --static-libs | egrep -- "-lssl( |^)" > /dev/null 2>&1 ; then
		check_pkg "libcrypto" || fail "libcrypto"
		check_pkg "libssl" || fail "libssl"
		echo "DEFINES+=-DHAVE_OPENSSL=1" >> config.mk
	elif curl-config --static-libs | grep -- -lgcrypt > /dev/null 2>&1 ; then
		check_pkg "gnutls" || fail "gnutls"
		check_custom "libgcrypt" "libgcrypt-config" || fail "libgcrypt"
		echo "DEFINES+=-DHAVE_GCRYPT=1" >> config.mk
	fi
}

echo "" > config.mk

command -v "$PKG_CONFIG" || fail_custom "$PKG_CONFIG not found, which is necessary to check for required build dependencies"
all_aboard_the_fail_boat # Exit early if $PKG_CONFIG cannot be found

check_pkg "sqlite3" || fail "sqlite3"
check_pkg "libcurl" || check_custom "libcurl" "curl-config" || fail "libcurl"
check_pkg "libxml-2.0" || check_custom "libxml2" "xml2-config" || fail "libxml2"
check_pkg "stfl" || fail "stfl"
check_cmd "asciidoctor" || echo "Install asciidoctor if you plan to build the documentation"
check_cmd "cargo" || fail "cargo"
( check_pkg "json" "" 0.11 || check_pkg "json-c" "" 0.11 ) || fail "json-c"

if [ `uname -s` = "Darwin" ]; then
	check_custom "ncurses5.4" "ncurses5.4-config" || fail "ncurses5.4"
    # rand crate needs Security framework, and rustc doesn't (can't) link it
    # into libnewsboat.a
    echo 'LDFLAGS+=-framework Security' >> config.mk
    # gettext-sys crate needs CoreFoundation framework, and rustc doesn't
    # (can't) link it into libnewsboat.a
    echo 'LDFLAGS+=-framework CoreFoundation' >> config.mk
elif [ `uname -s` != "OpenBSD" ]; then
	check_pkg "ncursesw" || \
	check_custom "ncursesw5" "ncursesw5-config" || \
		check_custom "ncursesw6" "ncursesw6-config" || fail "ncursesw"
fi
check_ssl_implementation
all_aboard_the_fail_boat
