/**
 * Copyright (c) 2012, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.openimaj.tools;

import java.io.File;
import java.io.IOException;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.kohsuke.args4j.Option;
import org.openimaj.io.FileUtils;

/**
 * A file tool reads and writes files and knows whether existing outputs should
 * be deleted
 *
 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
 *
 */
public abstract class InOutToolOptions {

        @Option(name = "--input", aliases = "-i", required = false, usage = "Input location", metaVar = "STRING")
        String input = null;

        @Option(name = "--output", aliases = "-o", required = false, usage = "output location", metaVar = "STRING")
        protected String output = null;

        @Option(
                        name = "--remove-existing-output",
                        aliases = "-rm",
                        required = false,
                        usage = "If existing output exists, remove it")
        boolean force = false;

        @Option(name = "--input-file", aliases = "-if", required = false, usage = "Get a set of inputs as listed in a file")
        private String inputFile = null;

        @Option(name = "--no-continue", aliases = "-nc", required = false, usage = "Do not continue an existing output")
        boolean contin = false;

        /**
         * @return the input string option
         */
        public String getInput() {
                return this.input;
        }

        /**
         * @return the input string option
         */
        public String getOutput() {
                return this.output;
        }

        /**
         * When the input file is set, any existing input file LIST file is removed
         * (anything from -if)
         *
         * @param input
         *            new input location
         */
        public void setInput(String input) {
                this.inputFile = null;
                this.input = input;
        }

        /**
         * @param output
         *            new input location
         */
        public void setOutput(String output) {
                this.output = output;
        }

        /**
         * @return the force option, whether the output should be overwritten if it
         *         exists
         */
        public boolean overwriteOutput() {
                return this.isForce();
        }

        /**
         * Fixes a problem with args4j with multivalued arguments being preserved
         * within the same JVM
         *
         * @param <T>
         * @param modeOptions
         * @param defaults
         *            optional default values if the modeoptions is empty
         */
        @SafeVarargs
        public static <T> void prepareMultivaluedArgument(List<T> modeOptions, T... defaults) {
                final Set<T> modes = new HashSet<T>();
                for (final T mode : modeOptions) {
                        modes.add(mode);
                }
                modeOptions.clear();
                modeOptions.addAll(modes);
                if (modeOptions.isEmpty()) {
                        for (final T t : defaults) {
                                modeOptions.add(t);
                        }
                }
        }

        /**
         * @return should files be forcefully removed
         */
        public boolean isForce() {
                return force;
        }

        /**
         * @return should existing files be continued from
         */
        public boolean isContinue() {
                return this.contin;
        }

        /**
         * @return all the inputs from the -if options file, or the single input if
         *         -i was not defined
         */
        public String[] getAllInputs() {
                boolean multifiles = this.getInputFile() != null;
                File inputFileF = null;
                if (multifiles) {
                        inputFileF = new File(this.getInputFile());
                        multifiles = inputFileF.exists() && inputFileF.canRead();
                }
                if (!multifiles) {
                        if (this.input == null)
                                return null;
                        return new String[] { this.input };
                } else {
                        try {
                                final String[] lines = FileUtils.readlines(inputFileF);
                                return lines;
                        } catch (final IOException e) {
                                if (this.input == null)
                                        return null;
                                return new String[] { this.input };
                        }
                }
        }

        /**
         * @return the input list file, each line is an input
         */
        public String getInputFile() {
                return inputFile;
        }

        /**
         * @param inputFile
         *            the new input file
         */
        public void setInputFile(String inputFile) {
                this.inputFile = inputFile;
        }
}