/*
Albert Cardona 2007
This work is in the Public Domain.
USE AT YOUR OWN RISK.
*/

import java.io.*;
import ij.plugin.PlugIn;
import ij.gui.GenericDialog;
import ij.io.DirectoryChooser;
import ij.IJ;

/** The program takes:
    - a string with which to select a subset of files.
    - a string to look for in the subset of selected files.
    - a replacement string.
    
    If a file with the new name exists already, the renaming will not happen for that file
    and a warning is issued to the log window and the terminal.
*/
public class Rename_Files implements PlugIn {

	public void run(String arg) {
		DirectoryChooser dc = new DirectoryChooser("Select directory");
		String dir = dc.getDirectory();
		if (null == dir || dir.startsWith("null")) return;
		GenericDialog gd = new GenericDialog("Renamer");
		gd.addMessage("Chosen dir:");
		gd.addMessage(dir);
		gd.addStringField("File name contains: ", "");
		gd.addStringField("Substring to replace: ", "");
		gd.addStringField("Replacement substring: ", "");
		gd.showDialog();
		if (gd.wasCanceled()) return;
		// test:
		//IJ.log("_" + dir + "_\n_" + gd.getNextString() + "_\n_" + gd.getNextString() + "_\n_" + gd.getNextString() + "_");
		main(new String[]{dir, gd.getNextString(), gd.getNextString(), gd.getNextString()});
	}

	static public void main(String[] args) {
		if (args.length < 4) {
			p("Usage: java Rename_Files <dir> <filter> <to_replace> <replacement>");
			return;
		}
		String sdir = args[0];
		String filter = args[1];
		String A = args[2];
		String B = args[3];
		if (null == args[0] || null == args[2] || null == args[3] ||
		    args[0].equals("null") || args[2].equals("null") || args[3].equals("null")) {
			p("Improper arguments");
			return;
		}
		File dir = new File(sdir);
		if (!dir.exists()) {
			p("Can't find directory " + sdir);
			return;
		}
		boolean use_filter = false;
		if (null != filter && filter.length() > 0) use_filter = true;
		try {
			String[] names = dir.list();
			for (int i=0; i<names.length; i++) {
				if (use_filter) {
					if (-1 == names[i].indexOf(filter)) continue;
				}
				if (-1 == names[i].indexOf(A)) continue;
				String new_name = names[i].replaceAll(A, B);
				File nf = new File(sdir + "/" + new_name);
				if (nf.exists()) {
					p("Can't rename '" + names[i] + "' to '" + new_name + "': file exists already");
					continue;
				}
				File f = new File(sdir + "/" + names[i]);
				f.renameTo(nf);
				p("Renamed '" + names[i] + "' to '" + new_name + "'");
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	static private void p(String msg) {
		System.out.println(msg);
		if (null != IJ.getInstance()) IJ.log(msg);
	}
}