--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/internal/FNCachePathHelper.java	Tue May 14 17:31:35 2013 +0200
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2013 TMate Software Ltd
+ *  
+ * 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 2 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.
+ *
+ * For information on how to redistribute this software under
+ * the terms of a license other than GNU General Public License
+ * contact TMate Software at support@hg4j.com
+ */
+package org.tmatesoft.hg.internal;
+
+import static org.tmatesoft.hg.internal.StoragePathHelper.STR_DATA;
+
+import org.tmatesoft.hg.util.PathRewrite;
+
+/**
+ * Prepare filelog names to be written into fncache. 
+ * 
+ * @see http://mercurial.selenic.com/wiki/fncacheRepoFormat#The_fncache_file
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+final class FNCachePathHelper implements PathRewrite {
+
+	private final EncodeDirPathHelper dirPathRewrite;
+
+	
+	public FNCachePathHelper() {
+		dirPathRewrite = new EncodeDirPathHelper();
+	}
+
+	/**
+	 * Input: repository-relative path of a filelog, i.e. without 'data/' or 'dh/' prefix, and/or '.i'/'.d' suffix.
+	 * Output: path ready to be written into fncache file, alaways with '.i' suffix (caller is free to alter the suffix to '.d' as appropriate
+	 */
+	public CharSequence rewrite(CharSequence path) {
+		CharSequence p = dirPathRewrite.rewrite(path);
+		StringBuilder result = new StringBuilder(p.length() + STR_DATA.length() + ".i".length());
+		result.append(STR_DATA);
+		result.append(p);
+		result.append(".i");
+		return result;
+	}
+
+	/*
+	 * There's always 'data/' prefix, even if actual file resides under 'dh/':
+	 *  
+	 * $ cat .hg/store/fncache
+	 * data/very-long-directory-name-level-1/very-long-directory-name-level-2/very-long-directory-name-level-3/file-with-longest-name-i-am-not-lazy-to-type.txt.i
+	 * $ ls .hg/store/dh/very-lon/very-lon/very-lon/
+	 * file-with-longest-name-i-am-not-lazy-to-type.txtbbd4d3327f6364027211b0cd8ca499d3d6308849.i
+	 */
+}