pakt

#!/bin/sh
# Pakt (PAcman KaTegories) - Pacman wrapper for categorizing packages
# v0.1.0 GPL-2.0
# https://github.com/mrminede/pakt

# Help message part.
if [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
	echo "PAKT: Displaying your package manager's help message.
	If you wanted to see pakt, see the man page at \`man pakt\`
	"
fi

# Save all the packages for a group of categories temporarily in /tmp.
# This is needed, because we allow different categories for different packages.
# We could do this with an array of some sort, but would lose POSIX-compliancy.
pkg_tempsave() {
	for cat in $(echo "$CATS" | tr ' ' '\n'); do
		for pkg in $PKGS; do
			echo "$pkg" >> /tmp/pakt/"$cat"
		done
	done

	PKGS=""
	CATS="$DEFAULT_CATEGORIES"
}

# Strict mode. The script will throw an error on an unbound variable encounter.
set -u

# Temporary path storing new package and category data.
mkdir -p "/tmp/pakt"

# Check whether the data path was defined with XDG.
if [ -z "${XDG_DATA_HOME:-}" ]; then
	DATA_PATH="$HOME/.local/share/pakt"
else
	DATA_PATH="$XDG_DATA_HOME/pakt"
fi
mkdir -p "$DATA_PATH"

# Control/set config path variable.
if [ -z "${PAKT_CONF_PATH:-}" ]; then
	PAKT_CONF_PATH="/etc"
fi

# Check whether pakt.conf exists in the first place.
if [ ! -e "$PAKT_CONF_PATH/pakt.conf" ]; then
	echo "PAKT: ERROR: /etc/pakt.conf not found. Exiting ..."
	exit 1
fi

. "$PAKT_CONF_PATH/pakt.conf"

# Process variables
CMD="$PACKAGE_MANAGER"
CATS="$DEFAULT_CATEGORIES"
PKGS=""
IS_TRANSACTION_COMMAND=0
TRANSACTION_READY=1
REMOVE_MODE=0

for arg in "$@"; do
	case "$arg" in
		"-S"*)
			CMD="${CMD} ${arg}"
			;;
		"-R"*)
			CMD="${CMD} ${arg}"
			REMOVE_MODE=1
			;;
		"-"*)
			#if the arg is part of the nonstdargs (has input after the arg e.g. --output ARG2.
			#We dont want to interpret ARG2 as a package, therefor we skip it)
			for nonstdarg in $NON_STD_ARGS; do
				if [ "$arg" -eq "$nonstdarg" ]; then
					SKIP_ARG=1
				fi
			done
			;;
		"++")
			CATS=$(ls "$DATA_PATH")
			;;
		"+"*)
			# Split up comma-separated categories (+cat1,cat2,test,cli).
			arg=$(echo "$arg" | tr ',' ' ')
			CATS="${CATS} ${arg#+}"

			# This is used to detect when a package is declared after a category.
			# When that happens, we want to first save the package and category data before resetting both.
			TRANSACTION_READY=0
			;;
		*)
			if [ $SKIP_ARG -eq 1 ]; then
				SKIP_ARG=0
				continue
			fi

			# See comment above.
			if [ "$TRANSACTION_READY" -eq 0 ]; then
				pkg_tempsave
				TRANSACTION_READY=1
			fi

			CMD="${CMD} ${arg}"
			PKGS="${PKGS} ${arg}"
			;;
	esac
done

# Save the last packages.
pkg_tempsave

# Execute pacman.
$CMD

if [ "$IS_TRANSACTION_COMMAND" -eq 1 ]; then
	echo "PAKT: NOTE: this doesn't look like a job for me. Exiting ..."
	exit 1
fi

if [ ! "$?" ]; then
	echo "PAKT: ERROR: package manager failed. Exiting..."
	exit 1
fi

# Omit the rest of the script if no category tomfoolery was performed.
if [ ! "$(ls /tmp/pakt)" ]; then
	exit
fi

for tmpfile in /tmp/pakt/*; do
	catfile=$DATA_PATH/`basename $tmpfile`
	touch $catfile

	for pkg in $(cat "$tmpfile"); do
		if [ "$REMOVE_MODE" -eq 1 ]; then
			# Remove package from category file.
			# You can't pipe directly into tmpfile because it would encounter an empty file.
			sed -i "/^$pkg$/d" "$catfile"
		elif [ "$pkg" != "$(grep "^$pkg\$" "$catfile")" ]; then
			# Add package to category file, if not already there.
			echo "$pkg" >> "$catfile"
		fi
	done
done

# At last we want to clean up, so we don't work on the packages from last time.
rm -r "/tmp/pakt"

# Clear empty catfiles from DATA_PATH. See the third setting in your `pakt.conf`.
if [ "$REMOVE_EMPTY_CATFILES" -eq 1 ]; then
	find "$DATA_PATH" -type f -empty -delete
fi