Reimplements functionality of makepkg to a small degree

makepkg.sh

#!/bin/bash -e

finalpath=/var/tmp/final

msg () {
	echo ":: $1"
}

noextract=
bfile=PKGBUILD
while [[ "$1" == "-"* ]]; do
	case "$1" in
		-e) noextract=1;;
		-p) bfile=$2; shift;;
		*) echo "don't support argument $1"; exit 1;;
	esac
	shift
done

if [ ! -f "$bfile" ]; then
	if [ -z "$2" ]; then
		echo "file not found (try pkgname + repo as args for download mode)"
		exit 1
	fi
	if [ "$2" == "aur" ]; then
		msg "Downloading PKGBUILD for $1 from AUR"
		git clone --depth=1 "https://aur.archlinux.org/$1.git" "$1"
	elif [[ "$2" =~ ^(core|extra|multilib)$ ]]; then
		msg "Downloading PKGBUILD for $1 (repo: $2)"
		git clone --depth=1 "https://gitlab.archlinux.org/archlinux/packaging/packages/$1.git/" "$1"
	else
		exit 1
	fi
	exit 0
fi

source "$bfile"

msg "Fetching sources"
for src in ${source[@]}; do
	[[ "$src" == *".sig" ]] && continue # meh

	filename=
	if [[ "$src" == *"::"* ]]; then # filename provided
		filename="${src%%::*}"
		src="${src#*::}"
	fi

	if [[ "$src" == "http://"* || "$src" == "https://"* || "$src" == "ftp://"* ]]; then
		[ -z "$filename" ] && filename="${src##*/}"
		[ ! -s "$filename" ] && wget "$src" -O "$filename"
	elif [[ "$src" == "git://"* || "$src" == "git+"* ]]; then
		checkout=
		if [ "${src#*#commit=}" != "$src" ]; then
			checkout="${src#*#commit=}"
		elif [ "${src#*#branch=}" != "$src" ]; then
			checkout="${src#*#branch=}"
		fi
		giturl="${src%%#*}"
		giturl="${giturl#git+}"
		if [ -z "$filename" ]; then
			filename="${giturl##*/}"
			filename="${filename%.git}"
		fi
		[ ! -d "$filename" ] && git clone "$giturl" "$filename"
		[[ -z "$noextract" && -n "$checkout" ]] && { cd "$filename"; git checkout "$checkout"; }
	elif [ -f "$src" ]; then
		[ -z "$filename" ] && filename="$src"
		[[ "$filename" != "$src" ]] && mv "$src" "$filename"
	else
		echo "Dunno how to download '$src', exiting"
		exit 1
	fi

	if [[ -z "$noextract" && "$filename" == *".tar."* ]]; then
		tar -axf "$filename"
	fi
done

srcdir=$PWD
mkdir -p pkg
pkgdir="$PWD/pkg"

if [[ -z "$noextract" && -n "$(type -t prepare)" ]]; then
	msg "Preparing"
	prepare
fi
msg "Building"
build
msg "Installing"
package
if [ -n "$finalpath" ]; then
	cp -a "$pkgdir"/* "$finalpath"
fi