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

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 * 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

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

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

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 * 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

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 *

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

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

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package org.netbeans.html.boot.fx;

import java.io.BufferedReader;

import java.io.Reader;

import java.net.URL;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.Executor;

import java.util.logging.Level;

import java.util.logging.Logger;

import javafx.application.Platform;

import javafx.scene.web.WebEngine;

import javafx.scene.web.WebView;

import netscape.javascript.JSObject;

import org.apidesign.html.boot.spi.Fn;

/**

 *

 * @author Jaroslav Tulach <jaroslav.tulach@apidesign.org>

 */

public abstract class AbstractFXPresenter 

implements Fn.Presenter, Fn.ToJavaScript, Fn.FromJavaScript, Executor {

    static final Logger LOG = Logger.getLogger(FXPresenter.class.getName());

    protected static int cnt;

    protected List<String> scripts;

    protected Runnable onLoad;

    protected WebEngine engine;

    @Override

    public Fn defineFn(String code, String... names) {

        return defineJSFn(code, names);

    }

    final JSFn defineJSFn(String code, String... names) {

        StringBuilder sb = new StringBuilder();

        sb.append("(function() {");

        sb.append("  return function(");

        String sep = "";

        for (String n : names) {

            sb.append(sep).append(n);

            sep = ",";

        }

        sb.append(") {\n");

        sb.append(code);

        sb.append("};");

        sb.append("})()");

        if (LOG.isLoggable(Level.FINE)) {

            LOG.log(Level.FINE, 

                "defining function #{0}:\n{1}\n", 

                new Object[] { ++cnt, code }

            );

        }

        JSObject x = (JSObject) engine.executeScript(sb.toString());

        return new JSFn(this, x, cnt);

    }

    @Override

    public void loadScript(Reader code) throws Exception {

        BufferedReader r = new BufferedReader(code);

        StringBuilder sb = new StringBuilder();

        for (;;) {

            String l = r.readLine();

            if (l == null) {

                break;

            }

            sb.append(l).append('\n');

        }

        final String script = sb.toString();

        if (scripts != null) {

            scripts.add(script);

        }

        engine.executeScript(script);

    }

    protected final void onPageLoad() {

        if (scripts != null) {

            for (String s : scripts) {

                engine.executeScript(s);

            }

        }

        onLoad.run();

    }

    @Override

    public void displayPage(final URL resource, final Runnable onLoad) {

        this.onLoad = onLoad;

        final WebView view = findView(resource);

        this.engine = view.getEngine();

        try {

            if (FXInspect.initialize(engine)) {

                scripts = new ArrayList<String>();

            }

        } catch (Throwable ex) {

            ex.printStackTrace();

        }

        class Run implements Runnable {

            @Override

            public void run() {

                if (scripts != null) {

                    view.setContextMenuEnabled(true);

                }

                engine.load(resource.toExternalForm());

            }

        }

        Run run = new Run();

        if (Platform.isFxApplicationThread()) {

            run.run();

        } else {

            Platform.runLater(run);

        }

        waitFinished();

    }

    protected abstract void waitFinished();

    protected abstract WebView findView(final URL resource);

    final JSObject convertArrays(Object[] arr) {

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

            if (arr[i] instanceof Object[]) {

                arr[i] = convertArrays((Object[]) arr[i]);

            }

        }

        final JSObject wrapArr = (JSObject)wrapArrFn().call("array", arr); // NOI18N

        return wrapArr;

    }

    private JSObject wrapArrImpl;

    private final JSObject wrapArrFn() {

        if (wrapArrImpl == null) {

            try {

                wrapArrImpl = (JSObject)defineJSFn("  var k = {};"

                    + "  k.array= function() {"

                    + "    return Array.prototype.slice.call(arguments);"

                    + "  };"

                    + "  return k;"

                ).invokeImpl(null, false);

            } catch (Exception ex) {

                throw new IllegalStateException(ex);

            }

        }

        return wrapArrImpl;

    }

    final Object checkArray(Object val) {

        int length = ((Number) arraySizeFn().call("array", val, null)).intValue();

        if (length == -1) {

            return val;

        }

        Object[] arr = new Object[length];

        arraySizeFn().call("array", val, arr);

        return arr;

    }

    private JSObject arraySize;

    private final JSObject arraySizeFn() {

        if (arraySize == null) {

            try {

                arraySize = (JSObject)defineJSFn("  var k = {};"

                    + "  k.array = function(arr, to) {"

                    + "    if (to === null) {"

                    + "      if (Object.prototype.toString.call(arr) === '[object Array]') return arr.length;"

                    + "      else return -1;"

                    + "    } else {"

                    + "      var l = arr.length;"

                    + "      for (var i = 0; i < l; i++) to[i] = arr[i];"

                    + "      return l;"

                    + "    }"

                    + "  };"

                    + "  return k;"

                ).invokeImpl(null, false);

            } catch (Exception ex) {

                throw new IllegalStateException(ex);

            }

        }

        return arraySize;

    }

    @Override

    public Object toJava(Object jsArray) {

        return checkArray(jsArray);

    }

    @Override

    public Object toJavaScript(Object toReturn) {

        if (toReturn instanceof Object[]) {

            return convertArrays((Object[])toReturn);

        } else {

            return toReturn;

        }

    }

    @Override public void execute(Runnable r) {

        if (Platform.isFxApplicationThread()) {

            r.run();

        } else {

            Platform.runLater(r);

        }

    }

    private static final class JSFn extends Fn {

        private final JSObject fn;

        private static int call;

        private final int id;

        public JSFn(AbstractFXPresenter p, JSObject fn, int id) {

            super(p);

            this.fn = fn;

            this.id = id;

        }

        @Override

        public Object invoke(Object thiz, Object... args) throws Exception {

            return invokeImpl(thiz, true, args);

        }

        final Object invokeImpl(Object thiz, boolean arrayChecks, Object... args) throws Exception {

            try {

                if (LOG.isLoggable(Level.FINE)) {

                    LOG.log(Level.FINE, "calling {0} function #{1}", new Object[]{++call, id});

                }

                List<Object> all = new ArrayList<Object>(args.length + 1);

                all.add(thiz == null ? fn : thiz);

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

                    if (arrayChecks && args[i] instanceof Object[]) {

                        Object[] arr = (Object[]) args[i];

                        Object conv = ((AbstractFXPresenter)presenter()).convertArrays(arr);

                        args[i] = conv;

                    }

                    all.add(args[i]);

                }

                Object ret = fn.call("call", all.toArray()); // NOI18N

                if (ret == fn) {

                    return null;

                }

                if (!arrayChecks) {

                    return ret;

                }

                return ((AbstractFXPresenter)presenter()).checkArray(ret);

            } catch (Error t) {

                t.printStackTrace();

                throw t;

            } catch (Exception t) {

                t.printStackTrace();

                throw t;

            }

        }

    }

}