/**
 * 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.ArrayList;
import java.util.List;

import org.openimaj.io.FileUtils;

/**
 * Tools for dealing with #InOutTool instances that are local file
 *
 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
 *
 */
public class FileToolsUtil {

        /**
         * Validate the (local) input from an {@link InOutToolOptions} and return
         * the corresponding file.
         *
         * @param tool
         *            the tool from which to get settings
         * @return a none null input file location if it exists
         * @throws IOException
         *             if the file doesn't exist
         */
        public static List<File> validateLocalInput(InOutToolOptions tool) throws IOException {
                if (tool.input == null && tool.getInputFile() == null) {
                        throw new IOException("No valid input provided");
                }
                List<File> toret = null;
                toret = new ArrayList<File>();
                if (tool.input != null) {
                        File f = new File(tool.input);
                        if (!f.exists())
                                throw new IOException("Couldn't file file");
                        toret.add(f);
                } else {
                        String[] allinputs = tool.getAllInputs();
                        for (String floc : allinputs) {
                                File f = new File(floc);
                                if (f.exists())
                                        toret.add(f);
                        }
                }
                return toret;

        }

        /**
         * Test whether the input is the stdin
         *
         * @param tool
         * @return true if input should be stdin, false otherwise.
         */
        public static boolean isStdin(InOutToolOptions tool) {
                if (tool.getInput() == null && tool.getInputFile() == null)
                        return true;
                return tool.getInput() != null && tool.getInput().equals("-");
        }

        /**
         * Test whether the requested output is stdout.
         *
         * @param tool
         *            the tool from which to get settings
         * @return true if output the stdout; false otherwise.
         */
        public static boolean isStdout(InOutToolOptions tool) {
                if (tool.getOutput() == null)
                        return true;
                return tool.getOutput().equals("-");
        }

        /**
         * Validate the (local) ouput from an {@link InOutToolOptions} and return
         * the corresponding file.
         *
         * @param tool
         *            the tool from which to get settings
         * @return the output file location, deleted if it is allowed to be deleted
         * @throws IOException
         *             if the file exists, but can't be deleted
         */
        public static File validateLocalOutput(InOutToolOptions tool) throws IOException {
                return validateLocalOutput(tool.output, tool.isForce(), tool.contin);
        }

        /**
         * Validate the (local) ouput from an String and return the corresponding
         * file.
         *
         * @param out
         *            where the file will go
         * @param overwrite
         *            whether to overwrite existing files
         * @return the output file location, deleted if it is allowed to be deleted
         * @throws IOException
         *             if the file exists, but can't be deleted
         */
        public static File validateLocalOutput(String out, boolean overwrite) throws IOException {
                return validateLocalOutput(out, overwrite, false);
        }

        /**
         * Validate the (local) ouput from an String and return the corresponding
         * file.
         *
         * @param out
         *            where the file will go
         * @param overwrite
         *            whether to overwrite existing files
         * @param contin
         *            whether an existing output should be continued (i.e. ignored
         *            if it exists)
         * @return the output file location, deleted if it is allowed to be deleted
         * @throws IOException
         *             if the file exists, but can't be deleted
         */
        public static File validateLocalOutput(String out, boolean overwrite, boolean contin) throws IOException {
                if (out == null) {
                        throw new IOException("No output specified");
                }
                File output = new File(out);
                if (output.exists()) {
                        if (overwrite) {
                                if (!FileUtils.deleteRecursive(output))
                                        throw new IOException("Couldn't delete existing output");
                        } else if (!contin) {
                                throw new IOException("Output already exists, didn't remove");
                        }
                }
                return output;
        }
}