MAJOR="4"
MINOR="19"
RELEASE="13"

VERSION="$MAJOR.$MINOR.$RELEASE"
SRCDIR="linux-$VERSION"
TARBALL="linux-$VERSION.tar.xz"
URL="https://www.kernel.org/pub/linux/kernel/v$MAJOR.x"
SHA256SUM="f50a77fc40e13fc406791346fa91926394205874cd50246c7c2374006bacc0c2"
DEPENDS="initrd"

get_linux_cpu() {
	case "$TARGET" in
	i*86-*)
		echo "x86"
		;;
	x86_64-*)
		echo "x86_64"
		;;
	arm-*)
		echo "arm"
		;;
	*)
		echo "don't know how to map $TARGET to Linux arch" >&2
		exit 1
		;;
	esac
}

prepare() {
	return
}

build() {
	local SOURCE="$1"
	local DEPLOY="$2"

	local INITRDDIR="$DEPLOY/initrd"
	local INITRDLIST="$INITRDDIR/initrd.list"
	local LINUX_CPU=$(get_linux_cpu)

	pkg install -omLD -R "$REPODIR" -r "$INITRDDIR" initrd
	pkg install -R "$REPODIR" -r "$INITRDDIR" -l -F initrd initrd > "$INITRDLIST"

	export KBUILD_OUTPUT="$PKGBUILDDIR"

	make -C "$1" O="$PKGBUILDDIR" ARCH="$LINUX_CPU" CROSS_COMPILE="${TARGET}-" mrproper
	cat_file_override "linux.config" > "$PKGBUILDDIR/.config"
	sed -i "$PKGBUILDDIR/.config" -e 's,^CONFIG_CROSS_COMPILE=.*,CONFIG_CROSS_COMPILE="'$TARGET'-",'
	sed -i "$PKGBUILDDIR/.config" -e 's,^CONFIG_INITRAMFS_SOURCE=.*,CONFIG_INITRAMFS_SOURCE="'$INITRDLIST'",'
	sed -i "$PKGBUILDDIR/.config" -e 's,^CONFIG_LOCALVERSION=.*,CONFIG_LOCALVERSION="-'${OS_NAME}-${OS_RELEASE}'",'
	make -C "$1" O="$PKGBUILDDIR" ARCH="$LINUX_CPU" CROSS_COMPILE="${TARGET}-" oldconfig
	make -C "$1" O="$PKGBUILDDIR" ARCH="$LINUX_CPU" CROSS_COMPILE="${TARGET}-" -j $NUMJOBS $LINUX_TGT

	rm -rf "$INITRDDIR"
}

deploy() {
	local SOURCE="$1"
	local DEPLOY="$2"
	local LINUX_CPU=$(get_linux_cpu)
	local target

	mkdir -p "$DEPLOY/boot" "$DEPLOY/lib/modules"

	for target in $LINUX_TGT; do
		case $target in
		*Image)
			cp "arch/$LINUX_CPU/boot/$target" "$DEPLOY/boot/vmlinuz"
			echo "dir boot 0755 0 0" >> "$DEPLOY/$PKGNAME.files"
			echo "file boot/vmlinuz 0755 0 0" >> "$DEPLOY/$PKGNAME.files"
			;;
		modules)
			export KBUILD_OUTPUT="$PKGBUILDDIR"
			make -C "$SOURCE" O="$PKGBUILDDIR" ARCH="$LINUX_CPU" CROSS_COMPILE="${TARGET}-" INSTALL_MOD_PATH="$DEPLOY" modules_install

			echo "dir lib 0755 0 0" >> "$DEPLOY/$PKGNAME.files"
			echo "dir lib/modules 0755 0 0" >> "$DEPLOY/$PKGNAME.files"

			find -H "$DEPLOY/lib" -type d -printf "dir %p 0%m 0 0\\n" |\
				tail -n +2 | sed "s#^$DEPLOY/##g" >> "$DEPLOY/$PKGNAME.files"

			find -H "$DEPLOY/lib" -type l -printf "slink %p 0%m 0 0 %l\\n" |\
				sed "s#^$DEPLOY/##g" >> "$DEPLOY/$PKGNAME.files"

			find -H "$DEPLOY/lib" -type f -printf "file %p 0%m 0 0\\n" |\
				sed "s#^$DEPLOY/##g" >> "$DEPLOY/$PKGNAME.files"
			;;
		esac
	done

	cp $SCRIPTDIR/pkg/$PKGNAME/*.desc "$DEPLOY"
}

check_update() {
	curl --silent -L https://www.kernel.org/feeds/kdist.xml | \
	     grep -o "[0-9.]*: longterm" | grep -o "[0-9.]*" | \
	     verson_find_greatest "$VERSION"
}