/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * 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 com.android.ahat;

class HtmlEscaper {
  /**
   * Escape html characters in the input string.
   */
  public static String escape(String text) {
    String specials = "&<>\'\"";
    String[] replacements = new String[]{"&amp;", "&lt;", "&gt;", "&apos;", "&quot;"};
    StringBuilder sb = null;
    int low = 0;
    for (int i = 0; i < text.length(); ++i) {
      int s = specials.indexOf(text.charAt(i));
      if (s != -1) {
        if (sb == null) {
          sb = new StringBuilder();
        }
        sb.append(text.substring(low, i));
        sb.append(replacements[s]);
        low = i + 1;
      }
    }
    if (sb == null) {
      return text;
    }

    sb.append(text.substring(low));
    return sb.toString();
  }
}