/**
 * Copyright 2010 Google 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.
 *
 */

package org.waveprotocol.wave.util.escapers;

import com.google.gwt.http.client.URL;

import org.waveprotocol.wave.model.waveref.InvalidWaveRefException;
import org.waveprotocol.wave.model.waveref.WaveRef;
import org.waveprotocol.wave.model.waveref.WaverefEncoder;
import org.waveprotocol.wave.model.waveref.WaverefEncoder.PercentEncoderDecoder;

/**
 * GWT-enabled instance of WaverefEncoder for use in the client.
 */
public class GwtWaverefEncoder {

  private static final PercentEscaper pathEscaper =
      new PercentEscaper(PercentEscaper.SAFEPATHCHARS_URLENCODER + "+", false);
  private static final PercentEscaper queryEscaper =
      new PercentEscaper(PercentEscaper.SAFEQUERYSTRINGCHARS_URLENCODER + "+", false);

  public static WaverefEncoder INSTANCE = new WaverefEncoder(new PercentEncoderDecoder() {
    @Override
    public String decode(String encodedValue) {
      return URL.decode(encodedValue);
    }

    @Override
    public String pathEncode(String decodedValue) {
      return pathEscaper.escape(decodedValue);
    }

    @Override
    public String queryEncode(String decodedValue) {
      return queryEscaper.escape(decodedValue);
    }
  });

  // Disallow construction
  private GwtWaverefEncoder() {
  }

  /** {@link WaverefEncoder#encodeToUriQueryString(String)} */
  public static String encodeToUriQueryString(String str) {
    return INSTANCE.encodeToUriQueryString(str);
  }

  /** {@link WaverefEncoder#encodeToUriPathSegment(String)} */
  public static String encodeToUriPathSegment(String str) {
    return INSTANCE.encodeToUriPathSegment(str);
  }

  /** {@link WaverefEncoder#encodeToUriQueryString(WaveRef)} */
  public static String encodeToUriQueryString(WaveRef ref) {
    return INSTANCE.encodeToUriQueryString(ref);
  }

  /** {@link WaverefEncoder#encodeToUriPathSegment(WaveRef)} */
  public static String encodeToUriPathSegment(WaveRef ref) {
    return INSTANCE.encodeToUriPathSegment(ref);
  }

  /** {@link WaverefEncoder#decodeWaveRefFromPath(String)} */
  public static WaveRef decodeWaveRefFromPath(String path) throws InvalidWaveRefException {
    return INSTANCE.decodeWaveRefFromPath(path);
  }
}