irssi

#!/bin/sh -

# Wrapper script around irssi that
# * Makes irssi (halfway) respect the XDG basedir spec;
# * Allows storing the password encrypted and in a different location;
# Written by ayekat on a cold Wednesday afternoon in january 2017.

set -fu

readonly IRSSI_HOME=$XDG_CONFIG_HOME/irssi
readonly IRSSI_CONFIG=$IRSSI_HOME/config
readonly IRSSI_HOME_REAL=$XDG_RUNTIME_DIR/irssi
readonly IRSSI_CONFIG_REAL=$IRSSI_HOME_REAL/config

readonly IRSSI_CONFIG_MARKER=${IRSSI_CONFIG_MARKER:-@}

die()
{
	retval=$(($1)); shift
	{
		# shellcheck disable=SC2059
		printf "$@"
		printf '\n'
	} >&2
	exit $retval
}

sedescape()
{
	printf '%s' "$1" | sed 's|\\|\\\\|g;s|/|\\/|g;s|"|\\\\"|'
}

if ! mkdir -p "$IRSSI_HOME_REAL"; then
	die 2 'Could not create temporary configuration directory %s' \
	      "$IRSSI_HOME_REAL"
fi

# Replace password if it is given:
if irssi_password_name=$(
	grep -oP \
		"(?<=${IRSSI_CONFIG_MARKER}IRC_PASSWORD:)[^${IRSSI_CONFIG_MARKER}]+" \
		"$IRSSI_CONFIG"
); then
	if ! irssi_password=$(pass show "services/$irssi_password_name"); then
		die 2 'Could not obtain IRC password'
	fi

	# Generate config with password:
	m="${IRSSI_CONFIG_MARKER}IRC_PASSWORD:[^$IRSSI_CONFIG_MARKER]\\+$IRSSI_CONFIG_MARKER"
	s=$(sedescape "$irssi_password")
	if ! sed "s/$m/$s/g" <"$IRSSI_CONFIG" >"$IRSSI_CONFIG_REAL"; then
		die 2 'Could not generate temporary irssi configuration file in %s' \
		      "$IRSSI_CONFIG_REAL"
	fi
else
	if ! cp "$IRSSI_CONFIG" "$IRSSI_CONFIG_REAL"; then
		die 2 'Could not copy configuration %s to temporary location %s' \
		      "$IRSSI_CONFIG" "$IRSSI_HOME_REAL"
	fi
fi

# Run irssi with the generated config:
exec unwrap irssi --home="$IRSSI_HOME" --config="$IRSSI_CONFIG_REAL" "$@"