#!/bin/bash

# Relational pipes

# Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)

#

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, version 3 of the License.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program. If not, see <http://www.gnu.org/licenses/>.

# This streamlet provides a single attribute: number of lines of given file

# Standard wc -l is used to count the lines.

# Directories are reported a 0 lines and with a null flag (will be supported in further Relational pipes versions).

. "$(dirname "$(realpath "$0")")/streamlet-common.sh"

processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES_METADATA() {

	send OUTPUT_ATTRIBUTE_METADATA "${outputAttributeAliases[0]-lines_count}"    "integer"

	send WAITING_FOR_INPUT_ATTRIBUTES

}

processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES() {

	if [[ -d "$currentFile" ]]; then

		isNull="true";

	else

		value=$(wc -l "$currentFile" | cut -d" " -f1);

		isNull="false";

	fi

	send OUTPUT_ATTRIBUTE "$value"    "$isNull";

	send WAITING_FOR_INPUT_ATTRIBUTES;

}

initialize

processMessages