// 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;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import org.chromium.sdk.JsFunction;

import org.chromium.sdk.JsObject;

import org.chromium.sdk.JsVariable;

import org.chromium.sdk.internal.tools.v8.MethodIsBlockingException;

/**

 * A generic implementation of the JsObject interface.

 */

class JsObjectImpl extends JsValueImpl implements JsObject {

  private final CallFrameImpl callFrame;

  private final String parentFqn;

  /**

   * This constructor implies the lazy resolution of object properties.

   *

   * @param callFrame where this instance belongs in

   * @param parentFqn the fully qualified name of the object parent

   * @param valueState the value data from the JS VM

   */

  JsObjectImpl(CallFrameImpl callFrame, String parentFqn, ValueMirror valueState) {

    super(valueState);

    this.callFrame = callFrame;

    this.parentFqn = parentFqn;

  }

  public Collection<JsVariableImpl> getProperties() throws MethodIsBlockingException {

    return subproperties.getPropertiesLazily();

  }

  public Collection<JsVariableImpl> getInternalProperties() throws MethodIsBlockingException {

    return internalProperties.getPropertiesLazily();

  }

  public String getRefId() {

    int ref = getMirror().getRef();

    if (ref < 0) {

      // Negative handle means that it's transient. We don't expose it.

      return null;

    } else {

      return String.valueOf(ref);

    }

  }

  @Override

  public String toString() {

    StringBuilder result = new StringBuilder();

    result.append("[JsObject: type=").append(getType());

    try {

      for (JsVariable prop : getProperties()) {

        result.append(',').append(prop);

      }

    } catch (MethodIsBlockingException e) {

      return "[JsObject: Exception in retrieving data]";

    }

    result.append(']');

    return result.toString();

  }

  @Override

  public JsObjectImpl asObject() {

    return this;

  }

  public JsArrayImpl asArray() {

    return null;

  }

  public JsFunction asFunction() {

    return null;

  }

  public JsVariable getProperty(String name) {

    return subproperties.getProperty(name);

  }

  public String getClassName() {

    return getMirror().getClassName();

  }

  protected JsVariableImpl.NameDecorator getChildPropertyNameDecorator() {

    return JsVariableImpl.NameDecorator.NOOP;

  }

  protected CallFrameImpl getCallFrame() {

    return callFrame;

  }

  Subproperties getSubpropertiesHelper() {

    return subproperties;

  }

  protected SubpropertiesMirror getSubpropertiesMirror() {

    ValueLoader valueLoader = callFrame.getInternalContext().getValueLoader();

    return valueLoader.loadSubpropertiesInMirror(getMirror()).getSubpropertiesMirror();

  }

  abstract class Subproperties {

    private List<JsVariableImpl> properties = null;

    private Map<String, JsVariableImpl> propertyMap = null;

    /**

     * Calls to this method must be synchronized on propertyLock.

     */

    private Map<String, JsVariableImpl> ensurePropertyMap() {

      if (propertyMap == null) {

        List<JsVariableImpl> propertiesList = getPropertiesLazily();

        Map<String, JsVariableImpl> map =

            new HashMap<String, JsVariableImpl>(propertiesList.size() * 2, 0.75f);

        for (JsVariableImpl prop : propertiesList) {

          map.put(prop.getName(), prop);

        }

        propertyMap = Collections.unmodifiableMap(map);

      }

      return propertyMap;

    }

    private List<JsVariableImpl> createPropertiesFromMirror(List<ValueMirror> mirrorProperties,

        List<? extends PropertyReference> propertyRefs) throws MethodIsBlockingException {

      // TODO(peter.rybin) Maybe assert that context is valid here

      List<JsVariableImpl> result = new ArrayList<JsVariableImpl>(mirrorProperties.size());

      for (int i = 0; i < mirrorProperties.size(); i++) {

        ValueMirror mirror = mirrorProperties.get(i);

        String varName = propertyRefs.get(i).getName();

        String fqn = getFullyQualifiedName(varName);

        if (fqn == null) {

          continue;

        }

        result.add(new JsVariableImpl(callFrame, mirror, varName, fqn,

            getNameDecorator()));

      }

      return result;

    }

    private String getFullyQualifiedName(String propName) {

      if (propName.startsWith(".")) {

        // ".arguments" is not legal

        return null;

      }

      return parentFqn + getNameDecorator().buildAccessSuffix(propName);

    }

    JsVariableImpl getProperty(String propertyName) {

      return ensurePropertyMap().get(propertyName);

    }

    List<JsVariableImpl> getPropertiesLazily() throws MethodIsBlockingException {

      synchronized (this) {

        if (properties == null) {

        List<? extends PropertyReference> propertyRefs = getPropertyRefs(getSubpropertiesMirror());

        ValueLoader valueLoader = callFrame.getInternalContext().getValueLoader();

        List<ValueMirror> subMirrors = valueLoader.getOrLoadValueFromRefs(propertyRefs);

          List<JsVariableImpl> wrappedProperties = createPropertiesFromMirror(subMirrors,

              propertyRefs);

          properties = Collections.unmodifiableList(wrappedProperties);

        }

        return properties;

      }

    }

    abstract JsVariableImpl.NameDecorator getNameDecorator();

    abstract List<? extends PropertyReference> getPropertyRefs(

        SubpropertiesMirror subpropertiesMirror);

  }

  private final Subproperties subproperties = new Subproperties() {

    @Override

    JsVariableImpl.NameDecorator getNameDecorator() {

      return getChildPropertyNameDecorator();

    }

    @Override

    List<? extends PropertyReference> getPropertyRefs(SubpropertiesMirror subpropertiesMirror) {

      return subpropertiesMirror.getProperties();

    }

  };

  private final Subproperties internalProperties = new Subproperties() {

    @Override

    JsVariableImpl.NameDecorator getNameDecorator() {

      return JsVariableImpl.NameDecorator.NOOP;

    }

    @Override

    List<? extends PropertyReference> getPropertyRefs(SubpropertiesMirror subpropertiesMirror) {

      return subpropertiesMirror.getInternalProperties();

    }

  };

}