/**

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

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  * Copyright 2013-2014 Oracle and/or its affiliates. All rights reserved.

  *

  * Oracle and Java are registered trademarks of Oracle and/or its affiliates.

  * Other names may be trademarks of their respective owners.

  *

  * The contents of this file are subject to the terms of either the GNU

  * General Public License Version 2 only ("GPL") or the Common

  * Development and Distribution License("CDDL") (collectively, the

  * "License"). You may not use this file except in compliance with the

  * License. You can obtain a copy of the License at

  * http://www.netbeans.org/cddl-gplv2.html

  * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the

  * specific language governing permissions and limitations under the

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  * nbbuild/licenses/CDDL-GPL-2-CP.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the GPL Version 2 section of the License file that

  * accompanied this code. If applicable, add the following below the

  * License Header, with the fields enclosed by brackets [] replaced by

  * your own identifying information:

  * "Portions Copyrighted [year] [name of copyright owner]"

  *

  * Contributor(s):

  *

  * The Original Software is NetBeans. The Initial Developer of the Original

  * Software is Oracle. Portions Copyright 2013-2014 Oracle. All Rights Reserved.

  *

  * If you wish your version of this file to be governed by only the CDDL

  * or only the GPL Version 2, indicate your decision by adding

  * "[Contributor] elects to include this software in this distribution

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  * your version of this file under either the CDDL, the GPL Version 2 or

  * to extend the choice of license to its licensees as provided above.

  * However, if you add GPL Version 2 code and therefore, elected the GPL

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 package org.netbeans.html.ko4j;

 import java.lang.ref.ReferenceQueue;

 import java.lang.ref.WeakReference;

 import java.util.Collections;

 import java.util.HashSet;

 import java.util.Set;

 import net.java.html.js.JavaScriptBody;

 import net.java.html.js.JavaScriptResource;

 import net.java.html.json.Model;

 import org.netbeans.html.json.spi.FunctionBinding;

 import org.netbeans.html.json.spi.PropertyBinding;

 /** This is an implementation package - just

  * include its JAR on classpath and use official {@link Context} API

  * to access the functionality.

  * <p>

  * Provides binding between {@link Model models} and knockout.js running

  * inside a JavaFX WebView. 

  *

  * @author Jaroslav Tulach

  */

 @JavaScriptResource("knockout-3.4.0.js")

 final class Knockout extends WeakReference<Object> {

     private static final ReferenceQueue<Object> QUEUE = new ReferenceQueue();

     private static final Set<Knockout> active = Collections.synchronizedSet(new HashSet<Knockout>());

     @JavaScriptBody(args = {"object", "property"}, body = 

         "var ret;\n" + 

         "if (property === null) ret = object;\n" + 

         "else if (object === null) ret = null;\n" + 

         "else ret = object[property];\n" + 

         "return ret ? ko.utils.unwrapObservable(ret) : null;"

     )

     static Object getProperty(Object object, String property) {

         return null;

     }

     private PropertyBinding[] props;

     private FunctionBinding[] funcs;

     private Object js;

     private Object strong;

     public Knockout(Object model, Object js, PropertyBinding[] props, FunctionBinding[] funcs) {

         super(model, QUEUE);

         this.js = js;

         this.props = new PropertyBinding[props.length];

         for (int i = 0; i < props.length; i++) {

             this.props[i] = props[i].weak();

         }

         this.funcs = new FunctionBinding[funcs.length];

         for (int i = 0; i < funcs.length; i++) {

             this.funcs[i] = funcs[i].weak();

         }

         active.add(this);

     }

     static void cleanUp() {

         for (;;) {

             Knockout ko = (Knockout)QUEUE.poll();

             if (ko == null) {

                 return;

             }

             active.remove(ko);

             clean(ko.js);

             ko.js = null;

             ko.props = null;

             ko.funcs = null;

         }

     }

     final void hold() {

         strong = get();

     }

     final Object getValue(int index) {

         return props[index].getValue();

     }

     final void setValue(int index, Object v) {

         if (v instanceof Knockout) {

             v = ((Knockout)v).get();

         }

         props[index].setValue(v);

     }

     final void call(int index, Object data, Object ev) {

         funcs[index].call(data, ev);

     }

     @JavaScriptBody(args = { "model", "prop", "oldValue", "newValue" }, 

         wait4js = false,

         body =

           "if (model) {\n"

         + "  var koProp = model[prop];\n"

         + "  if (koProp && koProp['valueHasMutated']) {\n"

         + "    if ((oldValue !== null || newValue !== null)) {\n"

         + "      koProp['valueHasMutated'](newValue);\n"

         + "    } else if (koProp['valueHasMutated']) {\n"

         + "      koProp['valueHasMutated']();\n"

         + "    }\n"

         + "  }\n"

         + "}\n"

     )

     public native static void valueHasMutated(

         Object model, String prop, Object oldValue, Object newValue

     );

     @JavaScriptBody(args = { "id", "bindings" }, body = 

         "var d = window['document'];\n" +

         "var e = id ? d['getElementById'](id) : d['body'];\n" +

         "ko['cleanNode'](e);\n" +

         "ko['applyBindings'](bindings, e);\n" +

         "return bindings['ko4j'];\n"

     )

     native static Object applyBindings(String id, Object bindings);

     @JavaScriptBody(args = { "cnt" }, body = 

         "var arr = new Array(cnt);\n" +

         "for (var i = 0; i < cnt; i++) arr[i] = new Object();\n" +

         "return arr;\n"

     )

     native static Object[] allocJS(int cnt);

     @JavaScriptBody(

         javacall = true,

         keepAlive = false,

         wait4js = false,

         args = { "ret", "copyFrom", "propNames", "propReadOnly", "propConstant", "propValues", "funcNames" },

         body = 

           "Object.defineProperty(ret, 'ko4j', { value : this });\n"

         + "function koComputed(index, name, readOnly, value) {\n"

         + "  var orig = copyFrom ? copyFrom[name] : null;\n"

         + "  if (!ko['isObservable'](orig)) {\n"

         + "    orig = null;\n"

         + "    var trigger = ko['observable']()['extend']({'notify':'always'});\n"

         + "  } else {\n"

         + "    var trigger = orig;\n"

         + "  }\n"

         + "  function realGetter() {\n"

         + "    var self = ret['ko4j'];\n"

         + "    try {\n"

         + "      var v = self ? self.@org.netbeans.html.ko4j.Knockout::getValue(I)(index) : null;\n"

         + "      return v;\n"

         + "    } catch (e) {\n"

         + "      alert(\"Cannot call getValue on \" + self + \" prop: \" + name + \" error: \" + e);\n"

         + "    }\n"

         + "  }\n"

         + "  var activeGetter = orig ? orig : function() { return value; };\n"

         + "  var bnd = {\n"

         + "    'read': function() {\n"

         + "      trigger();\n"

         + "      if (orig) {\n"

         + "        var r = orig();\n"

         + "      } else {\n"

         + "        var r = activeGetter();\n"

         + "        activeGetter = realGetter;\n"

         + "      }\n"

         + "      if (r) try { var br = r.valueOf(); } catch (err) {}\n"

         + "      return br === undefined ? r: br;\n"

         + "    },\n"

         + "    'owner': ret\n"

         + "  };\n"

         + "  if (!readOnly) {\n"

         + "    function write(val) {\n"

         + "      if (orig) orig(val);\n"

         + "      var self = ret['ko4j'];\n"

         + "      if (!self) return;\n"

         + "      var model = val ? val['ko4j'] : null;\n"

         + "      self.@org.netbeans.html.ko4j.Knockout::setValue(ILjava/lang/Object;)(index, model ? model : val);\n"

         + "    };\n"

         + "    bnd['write'] = write;\n"

         + "    if (orig) {\n"

         + "      write(orig());\n"

         + "      orig.subscribe(write);\n"

         + "    }\n"

         + "  };\n"

         + "  var cmpt = ko['computed'](bnd);\n"

         + "  cmpt['valueHasMutated'] = function(val) {\n"

         + "    if (arguments.length === 1) activeGetter = function() { return val; };\n"

         + "    trigger(val);\n"

         + "  };\n"

         + "  ret[name] = cmpt;\n"

         + "}\n"

         + "for (var i = 0; i < propNames.length; i++) {\n"

         + "  if (propConstant[i]) {\n"

         + "    ret[propNames[i]] = propValues[i];\n"

         + "  } else {\n"

         + "    koComputed(i, propNames[i], propReadOnly[i], propValues[i]);\n"

         + "  }\n"

         + "}\n"

         + "function koExpose(index, name) {\n"

         + "  ret[name] = function(data, ev) {\n"

         + "    var self = ret['ko4j'];\n"

         + "    if (!self) return;\n"

         + "    self.@org.netbeans.html.ko4j.Knockout::call(ILjava/lang/Object;Ljava/lang/Object;)(index, data, ev);\n"

         + "  };\n"

         + "}\n"

         + "for (var i = 0; i < funcNames.length; i++) {\n"

         + "  koExpose(i, funcNames[i]);\n"

         + "}\n"

         )

     native void wrapModel(

         Object ret, Object copyFrom,

         String[] propNames, Boolean[] propReadOnly, Boolean[] propConstant,

         Object propValues,

         String[] funcNames

     );

     @JavaScriptBody(args = { "js" }, wait4js = false, body = 

         "delete js['ko4j'];\n" +

         "for (var p in js) {\n" +

         "  delete js[p];\n" +

         "};\n" +

         "\n"

     )

     private static native void clean(Object js);

     @JavaScriptBody(args = { "o" }, body = "return o['ko4j'] ? o['ko4j'] : o;")

     private static native Object toModelImpl(Object wrapper);

     static Object toModel(Object wrapper) {

         Object o = toModelImpl(wrapper);

         if (o instanceof Knockout) {

             return ((Knockout)o).get();

         } else {

             return o;

         }

     }

 }