// Copyright (c) 2009 The Chromium Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

package org.chromium.sdk.internal.protocolparser.dynamicimpl;

import org.chromium.sdk.internal.protocolparser.JsonProtocolParseException;

import org.json.simple.JSONObject;

/**

 * A parser that generates dynamic proxy implementation of JsonType interface

 * for a {@link JSONObject}.

 * It creates dynamic proxy instance in 2 steps. First {@link #parseValue(Object, ObjectData)}

 * outputs {@link ObjectData}, which gets stored in field storage array. Later, when we are

 * about to return the value to a user, it is converted to a dynamic proxy instance by

 * {@link #VALUE_FINISHER} converter. We have to store an intermediate value for easier data

 * manipulation (dynamic proxy does not have any interfaces that we could make use of).

 */

class JsonTypeParser<T> extends SlowParser<ObjectData> {

  private final RefToType<T> refToType;

  private final boolean isNullable;

  private final boolean isSubtyping;

  JsonTypeParser(RefToType<T> refToType, boolean isNullable, boolean isSubtyping) {

    this.refToType = refToType;

    this.isNullable = isNullable;

    this.isSubtyping = isSubtyping;

  }

  RefToType<T> getType() {

    return refToType;

  }

  @Override

  public ObjectData parseValue(Object value, ObjectData thisData)

      throws JsonProtocolParseException {

    if (isNullable && value == null) {

      return null;

    }

    if (value == null) {

      throw new JsonProtocolParseException("null input");

    }

    TypeHandler<T> typeHandler = refToType.get();

    if (isSubtyping) {

      return typeHandler.parse(value, thisData);

    } else {

      return typeHandler.parseRootImpl(value);

    }

  }

  @Override

  public FieldLoadedFinisher getValueFinisher() {

    return VALUE_FINISHER;

  }

  @Override

  public JsonTypeParser<?> asJsonTypeParser() {

    return this;

  }

  public boolean isSubtyping() {

    return isSubtyping;

  }

  private static final FieldLoadedFinisher VALUE_FINISHER = new FieldLoadedFinisher() {

    @Override

    Object getValueForUser(Object cachedValue) {

      if (cachedValue == null) {

        return null;

      }

      ObjectData data = (ObjectData) cachedValue;

      return data.getProxy();

    }

  };

}