/*
 * MinIO Java SDK for Amazon S3 Compatible Cloud Storage, (C) 2016 MinIO, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import com.google.common.escape.Escaper;
import com.google.common.net.UrlEscapers;

public class S3Escaper {
  private static final Escaper ESCAPER = UrlEscapers.urlPathSegmentEscaper();

  /** Returns S3 encoded string. */
  public static String encode(String str) {
    if (str == null) {
      return "";
    }

    return ESCAPER
        .escape(str)
        .replaceAll("\\!", "%21")
        .replaceAll("\\$", "%24")
        .replaceAll("\\&", "%26")
        .replaceAll("\\'", "%27")
        .replaceAll("\\(", "%28")
        .replaceAll("\\)", "%29")
        .replaceAll("\\*", "%2A")
        .replaceAll("\\+", "%2B")
        .replaceAll("\\,", "%2C")
        .replaceAll("\\/", "%2F")
        .replaceAll("\\:", "%3A")
        .replaceAll("\\;", "%3B")
        .replaceAll("\\=", "%3D")
        .replaceAll("\\@", "%40")
        .replaceAll("\\[", "%5B")
        .replaceAll("\\]", "%5D");
  }

  /** Returns S3 encoded string of given path where multiple '/' are trimmed. */
  public static String encodePath(String path) {
    final StringBuilder encodedPath = new StringBuilder();
    for (String pathSegment : path.split("/")) {
      if (!pathSegment.isEmpty()) {
        if (encodedPath.length() > 0) {
          encodedPath.append("/");
        }
        encodedPath.append(S3Escaper.encode(pathSegment));
      }
    }

    if (path.startsWith("/")) {
      encodedPath.insert(0, "/");
    }
    if (path.endsWith("/")) {
      encodedPath.append("/");
    }

    return encodedPath.toString();
  }
}