/*
Copyright 2007-2010 WebDriver committers
Copyright 2007-2010 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.openqa.selenium.remote.internal;

import com.google.common.base.Function;
import com.google.common.collect.Collections2;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;

import org.openqa.selenium.WebElement;
import org.openqa.selenium.internal.WrapsElement;
import org.openqa.selenium.remote.RemoteWebElement;

import java.util.Collection;
import java.util.Map;

/**
 * Converts {@link WebElement} objects to their JSON representation. Will recursively convert Lists
 * and Maps to catch nested references.
 */
public class WebElementToJsonConverter implements Function<Object, Object> {
  public Object apply(Object arg) {
    if (arg == null || arg instanceof String || arg instanceof Boolean ||
        arg instanceof Number) {
      return arg;
    }

    while (arg instanceof WrapsElement) {
      arg = ((WrapsElement) arg).getWrappedElement();
    }

    if (arg instanceof RemoteWebElement) {
      return ImmutableMap.of("ELEMENT", ((RemoteWebElement) arg).getId());
    }

    if (arg instanceof Collection<?>) {
      Collection<?> args = (Collection<?>) arg;
      return Collections2.transform(args, this);
    }

    if (arg instanceof Map<?, ?>) {
      Map<?, ?> args = (Map<?, ?>) arg;
      Map<String, Object> converted = Maps.newHashMapWithExpectedSize(args.size());
      for (Map.Entry<?, ?> entry : args.entrySet()) {
        Object key = entry.getKey();
        if (!(key instanceof String)) {
          throw new IllegalArgumentException(
              "All keys in Map script arguments must be strings: " + key.getClass().getName());
        }
        converted.put((String) key, apply(entry.getValue()));
      }
      return converted;
    }

    throw new IllegalArgumentException("Argument is of an illegal type: "
        + arg.getClass().getName());
  }
}

@@ -1069,16 +1069,22 @@
  %7B@link 
+Remote
 WebEleme
@@ -1098,40 +1098,147 @@
 ects
- to their JSON representation. W
+, which may be%0D%0A * %7B@link WrapsElement wrapped%7D, into their JSON representation as defined by%0D%0A * the WebDriver wire protocol. This class w
 ill 
@@ -1266,16 +1266,16 @@
 ists
-%0D%0A *
  and
+%0D%0A *
  Map
@@ -1305,16 +1305,160 @@
 ences.%0D%0A
+ *%0D%0A * @see %3Ca href=%22http://code.google.com/p/selenium/wiki/JsonWireProtocol#WebElement_JSON_Object%22%3E%0D%0A *     WebDriver JSON Wire Protocol%3C/a%3E%0D%0A
  */%0D%0Apub

Clarify javadoc on WebElementToJsonConverter.