/**

  * 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

  * 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

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

  *

  * Contributor(s):

  *

  * 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

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

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

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  * 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.json.impl;

 import java.io.IOException;

 import java.io.InputStream;

 import java.util.HashMap;

 import java.util.Map;

 import net.java.html.BrwsrCtx;

 import org.apidesign.html.context.spi.Contexts;

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

 import org.apidesign.html.json.spi.JSONCall;

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

 import org.apidesign.html.json.spi.Technology;

 import org.apidesign.html.json.spi.Transfer;

 import org.apidesign.html.json.spi.WSTransfer;

 /**

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 public final class JSON {

     private JSON() {

     }

     static Technology<?> findTechnology(BrwsrCtx c) {

         Technology<?> t = Contexts.find(c, Technology.class);

         return t == null ? EmptyTech.EMPTY : t;

     }

     static Transfer findTransfer(BrwsrCtx c) {

         Transfer t = Contexts.find(c, Transfer.class);

         return t == null ? EmptyTech.EMPTY : t;

     }

     static WSTransfer<?> findWSTransfer(BrwsrCtx c) {

         WSTransfer<?> t = Contexts.find(c, WSTransfer.class);

         return t == null ? EmptyTech.EMPTY : t;

     }

     public static void runInBrowser(BrwsrCtx c, Runnable runnable) {

         findTechnology(c).runSafe(runnable);

     }

     public static void extract(BrwsrCtx c, Object value, String[] props, Object[] values) {

         Transfer t = findTransfer(c);

         t.extract(value, props, values);

     }

     private static Object getProperty(BrwsrCtx c, Object obj, String prop) {

         if (prop == null) return obj;

         String[] arr = { prop };

         Object[] val = { null };

         extract(c, obj, arr, val);

         return val[0];

     }

     public static Object toJSON(Object value) {

         if (value == null) {

             return "null";

         }

         if (value instanceof Enum) {

             value = value.toString();

         }

         if (value instanceof String) {

             String s = (String)value;

             int len = s.length();

             StringBuilder sb = new StringBuilder(len + 10);

             sb.append('"');

             for (int i = 0; i < len; i++) {

                 char ch = s.charAt(i);

                 switch (ch) {

                     case '\"': sb.append("\\\""); break;

                     case '\n': sb.append("\\n"); break;

                     case '\r': sb.append("\\r"); break;

                     case '\t': sb.append("\\t"); break;

                     case '\\': sb.append("\\\\"); break;

                     default: sb.append(ch);

                 }

             }

             sb.append('"');

             return sb.toString();

         }

         return value.toString();

     }

     public static String toString(BrwsrCtx c, Object obj, String prop) {

         obj = getProperty(c, obj, prop);

         return obj instanceof String ? (String)obj : null;

     }

     public static Number toNumber(BrwsrCtx c, Object obj, String prop) {

         obj = getProperty(c, obj, prop);

         if (!(obj instanceof Number)) {

             obj = Double.NaN;

         }

         return (Number)obj;

     }

     public static <M> M toModel(BrwsrCtx c, Class<M> aClass, Object data, Object object) {

         Technology<?> t = findTechnology(c);

         Object o = t.toModel(aClass, data);

         return aClass.cast(o);

     }

     public static boolean isSame(int a, int b) {

         return a == b;

     }

     public static boolean isSame(double a, double b) {

         return a == b;

     }

     public static boolean isSame(Object a, Object b) {

         if (a == b) {

             return true;

         }

         if (a == null || b == null) {

             return false;

         }

         return a.equals(b);

     }

     public static int hashPlus(Object o, int h) {

         return o == null ? h : h ^ o.hashCode();

     }

     public static <T> T extractValue(Class<T> type, Object val) {

         if (Number.class.isAssignableFrom(type)) {

             val = numberValue(val);

         }

         if (Boolean.class == type) {

             val = boolValue(val);

         }

         if (String.class == type) {

             val = stringValue(val);

         }

         if (Character.class == type) {

             val = charValue(val);

         }

         if (Integer.class == type) {

             val = val instanceof Number ? ((Number)val).intValue() : 0;

         }

         if (Long.class == type) {

             val = val instanceof Number  ? ((Number)val).longValue() : 0;

         }

         if (Short.class == type) {

             val = val instanceof Number ? ((Number)val).shortValue() : 0;

         }

         if (Byte.class == type) {

             val = val instanceof Number ? ((Number)val).byteValue() : 0;

         }        

         if (Double.class == type) {

             val = val instanceof Number ? ((Number)val).doubleValue() : Double.NaN;

         }

         if (Float.class == type) {

             val = val instanceof Number ? ((Number)val).floatValue() : Float.NaN;

         }

         return type.cast(val);

     }

     protected static boolean isNumeric(Object val) {

         return ((val instanceof Integer) || (val instanceof Long) || (val instanceof Short) || (val instanceof Byte));

     }

     public static String stringValue(Object val) {

         if (val instanceof Boolean) {

             return ((Boolean)val ? "true" : "false");

         }

         if (isNumeric(val)) {

             return Long.toString(((Number)val).longValue());

         }

         if (val instanceof Float) {

             return Float.toString((Float)val);

         }

         if (val instanceof Double) {

             return Double.toString((Double)val);

         }

         return (String)val;

     }

     public static Number numberValue(Object val) {

         if (val instanceof String) {

             try {

                 return Double.valueOf((String)val);

             } catch (NumberFormatException ex) {

                 return Double.NaN;

             }

         }

         if (val instanceof Boolean) {

             return (Boolean)val ? 1 : 0;

         }

         return (Number)val;

     }

     public static Character charValue(Object val) {

         if (val instanceof Number) {

             return Character.toChars(numberValue(val).intValue())[0];

         }

         if (val instanceof Boolean) {

             return (Boolean)val ? (char)1 : (char)0;

         }

         if (val instanceof String) {

             String s = (String)val;

             return s.isEmpty() ? (char)0 : s.charAt(0);

         }

         return (Character)val;

     }

     public static Boolean boolValue(Object val) {

         if (val instanceof String) {

             return Boolean.parseBoolean((String)val);

         }

         if (val instanceof Number) {

             return numberValue(val).doubleValue() != 0.0;

         }

         return Boolean.TRUE.equals(val);

     }

     public static void loadJSON(

         BrwsrCtx c, RcvrJSON callback,

         String urlBefore, String urlAfter, String method,

         Object data

     ) {

         JSONCall call = PropertyBindingAccessor.createCall(c, callback, urlBefore, urlAfter, method, data);

         Transfer t = findTransfer(c);

         t.loadJSON(call);

     }

     public static WS openWS(

         BrwsrCtx c, RcvrJSON r, String url, Object data

     ) {

         WS ws = WSImpl.create(findWSTransfer(c), r);

         ws.send(c, url, data);

         return ws;

     }

     public static abstract class WS {

         private WS() {

         }

         public abstract void send(BrwsrCtx ctx, String url, Object model);

     }

     private static final class WSImpl<Socket> extends WS {

         private final WSTransfer<Socket> trans;

         private final RcvrJSON rcvr;

         private Socket socket;

         private String prevURL;

         private WSImpl(WSTransfer<Socket> trans, RcvrJSON rcvr) {

             this.trans = trans;

             this.rcvr = rcvr;

         }

         static <Socket> WS create(WSTransfer<Socket> t, RcvrJSON r) {

             return new WSImpl<Socket>(t, r);

         }

         @Override

         public void send(BrwsrCtx ctx, String url, Object data) {

             Socket s = socket;

             if (s == null) {

                 if (data != null) {

                     throw new IllegalStateException("WebSocket is not opened yet. Call with null data, was: " + data);

                 }

                 JSONCall call = PropertyBindingAccessor.createCall(ctx, rcvr, url, null, "WebSocket", null);

                 socket = trans.open(url, call);

                 prevURL = url;

                 return;

             }

             if (data == null) {

                 trans.close(s);

                 socket = null;

                 return;

             }

             if (!prevURL.equals(url)) {

                 throw new IllegalStateException(

                     "Can't call to different URL " + url + " was: " + prevURL + "!"

                     + " Close the socket by calling it will null data first!"

                 );

             }

             JSONCall call = PropertyBindingAccessor.createCall(ctx, rcvr, prevURL, null, "WebSocket", data);

             trans.send(s, call);

         }

     }

     private static final Map<Class,FromJSON<?>> froms;

     static {

         Map<Class,FromJSON<?>> m = new HashMap<Class,FromJSON<?>>();

         froms = m;

     }

     public static void register(FromJSON<?> from) {

         froms.put(from.factoryFor(), from);

     }

     public static boolean isModel(Class<?> clazz) {

         return findFrom(clazz) != null; 

     }

     private static FromJSON<?> findFrom(Class<?> clazz) {

         for (int i = 0; i < 2; i++) {

             FromJSON<?> from = froms.get(clazz);

             if (from == null) {

                 initClass(clazz);

             } else {

                 return from;

             }

         }

         return null;

     }

     public static <Model> Model bindTo(Model model, BrwsrCtx c) {

         FromJSON<?> from = findFrom(model.getClass());

         if (from == null) {

             throw new IllegalArgumentException();

         }

         return (Model) from.cloneTo(model, c);

     }

     public static <T> T readStream(BrwsrCtx c, Class<T> modelClazz, InputStream data) 

     throws IOException {

         Transfer tr = findTransfer(c);

         return read(c, modelClazz, tr.toJSON((InputStream)data));

     }

     public static <T> T read(BrwsrCtx c, Class<T> modelClazz, Object data) {

         if (data == null) {

             return null;

         }

         if (modelClazz == String.class) {

             return modelClazz.cast(data.toString());

         }

         for (int i = 0; i < 2; i++) {

             FromJSON<?> from = froms.get(modelClazz);

             if (from == null) {

                 initClass(modelClazz);

             } else {

                 return modelClazz.cast(from.read(c, data));

             }

         }

         throw new NullPointerException();

     }

     static void initClass(Class<?> modelClazz) {

         try {

             // try to resolve the class

             ClassLoader l;

             try {

                 l = modelClazz.getClassLoader();

             } catch (SecurityException ex) {

                 l = null;

             }

             if (l != null) {

                 Class.forName(modelClazz.getName(), true, l);

             }

             modelClazz.newInstance();

         } catch (Exception ex) {

             // ignore and try again

         }

     }

     private static final class EmptyTech

     implements Technology<Object>, Transfer, WSTransfer<Void> {

         private static final EmptyTech EMPTY = new EmptyTech();

         @Override

         public Object wrapModel(Object model) {

             return model;

         }

         @Override

         public void valueHasMutated(Object data, String propertyName) {

         }

         @Override

         public void bind(PropertyBinding b, Object model, Object data) {

         }

         @Override

         public void expose(FunctionBinding fb, Object model, Object d) {

         }

         @Override

         public void applyBindings(Object data) {

         }

         @Override

         public Object wrapArray(Object[] arr) {

             return arr;

         }

         @Override

         public void extract(Object obj, String[] props, Object[] values) {

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

                 values[i] = null;

             }

         }

         @Override

         public void loadJSON(JSONCall call) {

             call.notifyError(new UnsupportedOperationException());

         }

         @Override

         public <M> M toModel(Class<M> modelClass, Object data) {

             return modelClass.cast(data);

         }

         @Override

         public Object toJSON(InputStream is) throws IOException {

             throw new IOException("Not supported");

         }

         @Override

         public synchronized void runSafe(Runnable r) {

             r.run();

         }

         @Override

         public Void open(String url, JSONCall onReply) {

             onReply.notifyError(new UnsupportedOperationException("WebSockets not supported!"));

             return null;

         }

         @Override

         public void send(Void socket, JSONCall data) {

         }

         @Override

         public void close(Void socket) {

         }

     }

 }