/**

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

 *

 * 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

 * License.  When distributing the software, include this License Header

 * Notice in each file and include the License file at

 * 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

 * under the [CDDL or GPL Version 2] license." If you do not indicate a

 * single choice of license, a recipient has the option to distribute

 * 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

 * Version 2 license, then the option applies only if the new code is

 * made subject to such option by the copyright holder.

 */

package org.netbeans.html.json.impl;

import java.io.IOException;

import java.io.OutputStreamWriter;

import java.io.StringWriter;

import java.io.Writer;

import java.lang.annotation.AnnotationTypeMismatchException;

import java.lang.annotation.IncompleteAnnotationException;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.HashSet;

import java.util.LinkedHashSet;

import java.util.List;

import java.util.Map;

import java.util.ResourceBundle;

import java.util.Set;

import java.util.WeakHashMap;

import java.util.logging.Level;

import java.util.logging.Logger;

import javax.annotation.processing.AbstractProcessor;

import javax.annotation.processing.Completion;

import javax.annotation.processing.Completions;

import javax.annotation.processing.ProcessingEnvironment;

import javax.annotation.processing.Processor;

import javax.annotation.processing.RoundEnvironment;

import javax.annotation.processing.SupportedAnnotationTypes;

import javax.annotation.processing.SupportedSourceVersion;

import javax.lang.model.SourceVersion;

import javax.lang.model.element.AnnotationMirror;

import javax.lang.model.element.AnnotationValue;

import javax.lang.model.element.Element;

import javax.lang.model.element.ElementKind;

import javax.lang.model.element.ExecutableElement;

import javax.lang.model.element.Modifier;

import javax.lang.model.element.PackageElement;

import javax.lang.model.element.TypeElement;

import javax.lang.model.element.VariableElement;

import javax.lang.model.type.ArrayType;

import javax.lang.model.type.DeclaredType;

import javax.lang.model.type.MirroredTypeException;

import javax.lang.model.type.TypeKind;

import javax.lang.model.type.TypeMirror;

import javax.lang.model.util.Elements;

import javax.lang.model.util.Types;

import javax.tools.Diagnostic;

import javax.tools.FileObject;

import net.java.html.json.ComputedProperty;

import net.java.html.json.Model;

import net.java.html.json.Function;

import net.java.html.json.ModelOperation;

import net.java.html.json.OnPropertyChange;

import net.java.html.json.OnReceive;

import net.java.html.json.Property;

import org.openide.util.lookup.ServiceProvider;

/** Annotation processor to process {@link Model @Model} annotations and

 * generate appropriate model classes.

 *

 * @author Jaroslav Tulach

 */

@ServiceProvider(service=Processor.class)

@SupportedSourceVersion(SourceVersion.RELEASE_6)

@SupportedAnnotationTypes({

    "net.java.html.json.Model",

    "net.java.html.json.ModelOperation",

    "net.java.html.json.Function",

    "net.java.html.json.OnReceive",

    "net.java.html.json.OnPropertyChange",

    "net.java.html.json.ComputedProperty",

    "net.java.html.json.Property"

})

public final class ModelProcessor extends AbstractProcessor {

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

    private final Map<Element,String> models = new WeakHashMap<Element,String>();

    private final Map<Element,Prprt[]> verify = new WeakHashMap<Element,Prprt[]>();

    @Override

    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

        boolean ok = true;

        for (Element e : roundEnv.getElementsAnnotatedWith(Model.class)) {

            if (!processModel(e)) {

                ok = false;

            }

        }

        if (roundEnv.processingOver()) {

            models.clear();

            for (Map.Entry<Element, Prprt[]> entry : verify.entrySet()) {

                TypeElement te = (TypeElement)entry.getKey();

                String fqn = processingEnv.getElementUtils().getBinaryName(te).toString();

                Element finalElem = processingEnv.getElementUtils().getTypeElement(fqn);

                if (finalElem == null) {

                    continue;

                }

                Prprt[] props;

                Model m = finalElem.getAnnotation(Model.class);

                if (m == null) {

                    continue;

                }

                props = Prprt.wrap(processingEnv, finalElem, m.properties());

                for (Prprt p : props) {

                    boolean[] isModel = { false };

                    boolean[] isEnum = { false };

                    boolean[] isPrimitive = { false };

                    String t = checkType(p, isModel, isEnum, isPrimitive);

                    if (isEnum[0]) {

                        continue;

                    }

                    if (isPrimitive[0]) {

                        continue;

                    }

                    if (isModel[0]) {

                        continue;

                    }

                    if ("java.lang.String".equals(t)) {

                        continue;

                    }

                    error("The type " + t + " should be defined by @Model annotation", entry.getKey());

                }

            }

            verify.clear();

        }

        return ok;

    }

    private void error(String msg, Element e) {

        processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, msg, e);

    }

    private boolean processModel(Element e) {

        boolean ok = true;

        Model m = e.getAnnotation(Model.class);

        if (m == null) {

            return true;

        }

        String pkg = findPkgName(e);

        Writer w;

        String className = m.className();

        models.put(e, className);

        try {

            StringWriter body = new StringWriter();

            StringBuilder onReceiveType = new StringBuilder();

            List<GetSet> propsGetSet = new ArrayList<GetSet>();

            List<Object> functions = new ArrayList<Object>();

            Map<String, Collection<String[]>> propsDeps = new HashMap<String, Collection<String[]>>();

            Map<String, Collection<String>> functionDeps = new HashMap<String, Collection<String>>();

            Prprt[] props = createProps(e, m.properties());

            if (!generateComputedProperties(body, props, e.getEnclosedElements(), propsGetSet, propsDeps)) {

                ok = false;

            }

            if (!generateOnChange(e, propsDeps, props, className, functionDeps)) {

                ok = false;

            }

            if (!generateProperties(e, body, className, props, propsGetSet, propsDeps, functionDeps)) {

                ok = false;

            }

            if (!generateFunctions(e, body, className, e.getEnclosedElements(), functions)) {

                ok = false;

            }

            int functionsCount = functions.size() / 2;

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

                for (Prprt p : props) {

                    if (p.name().equals(functions.get(i))) {

                        error("Function cannot have the name of an existing property", e);

                        ok = false;

                    }

                }

            }

            if (!generateReceive(e, body, className, e.getEnclosedElements(), onReceiveType)) {

                ok = false;

            }

            if (!generateOperation(e, body, className, e.getEnclosedElements(), functions)) {

                ok = false;

            }

            FileObject java = processingEnv.getFiler().createSourceFile(pkg + '.' + className, e);

            w = new OutputStreamWriter(java.openOutputStream());

            try {

                w.append("package " + pkg + ";\n");

                w.append("import net.java.html.json.*;\n");

                w.append("public final class ").append(className).append(" implements Cloneable {\n");

                w.append("  private static final Html4JavaType TYPE = new Html4JavaType();\n");

                w.append("  private final org.netbeans.html.json.spi.Proto proto;\n");

                w.append(body.toString());

                w.append("  private static Class<" + inPckName(e) + "> modelFor() { return null; }\n");

                w.append("  private ").append(className).append("(net.java.html.BrwsrCtx context) {\n");

                w.append("    this.proto = TYPE.createProto(this, context);\n");

                for (Prprt p : props) {

                    if (p.array()) {

                        final String tn = typeName(e, p);

                        String[] gs = toGetSet(p.name(), tn, p.array());

                        w.write("    this.prop_" + p.name() + " = proto.createList(\""

                            + p.name() + "\"");

                        if (functionDeps.containsKey(p.name())) {

                            int index = Arrays.asList(functionDeps.keySet().toArray()).indexOf(p.name());

                            w.write(", " + index);

                        } else {

                            w.write(", -1");

                        }

                        Collection<String[]> dependants = propsDeps.get(p.name());

                        if (dependants != null) {

                            for (String[] depProp : dependants) {

                                w.write(", ");

                                w.write('\"');

                                w.write(depProp[0]);

                                w.write('\"');

                            }

                        }

                        w.write(")");

                        w.write(";\n");

                    }

                }

                w.append("  };\n");

                w.append("  public ").append(className).append("() {\n");

                w.append("    this(net.java.html.BrwsrCtx.findDefault(").append(className).append(".class));\n");

                for (Prprt p : props) {

                    if (!p.array()) {

                        boolean[] isModel = {false};

                        boolean[] isEnum = {false};

                        boolean isPrimitive[] = {false};

                        String tn = checkType(p, isModel, isEnum, isPrimitive);

                        if (isModel[0]) {

                            w.write("    prop_" + p.name() + " = new " + tn + "();\n");

                        }

                    }

                }

                w.append("  };\n");

                if (props.length > 0) {

                    w.append("  public ").append(className).append("(");

                    Prprt firstArray = null;

                    String sep = "";

                    for (Prprt p : props) {

                        if (p.array()) {

                            if (firstArray == null) {

                                firstArray = p;

                            }

                            continue;

                        }

                        String tn = typeName(e, p);

                        w.write(sep);

                        w.write(tn);

                        w.write(" " + p.name());

                        sep = ", ";

                    }

                    if (firstArray != null) {

                        String tn;

                        boolean[] isModel = {false};

                        boolean[] isEnum = {false};

                        boolean isPrimitive[] = {false};

                        tn = checkType(firstArray, isModel, isEnum, isPrimitive);

                        w.write(sep);

                        w.write(tn);

                        w.write("... " + firstArray.name());

                    }

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

                    w.append("    this(net.java.html.BrwsrCtx.findDefault(").append(className).append(".class));\n");

                    for (Prprt p : props) {

                        if (p.array()) {

                            continue;

                        }

                        w.write("    this.prop_" + p.name() + " = " + p.name() + ";\n");

                    }

                    if (firstArray != null) {

                        w.write("    proto.initTo(this.prop_" + firstArray.name() + ", " + firstArray.name() + ");\n");

                    }

                    w.append("  };\n");

                }

                w.append("  private static class Html4JavaType extends org.netbeans.html.json.spi.Proto.Type<").append(className).append("> {\n");

                w.append("    private Html4JavaType() {\n      super(").append(className).append(".class, ").

                    append(inPckName(e)).append(".class, " + propsGetSet.size() + ", "

                    + functionsCount + ");\n");

                {

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

                        w.append("      registerProperty(\"").append(propsGetSet.get(i).name).append("\", ");

                        w.append((i) + ", " + propsGetSet.get(i).readOnly + ");\n");

                    }

                }

                {

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

                        w.append("      registerFunction(\"").append((String)functions.get(i * 2)).append("\", ");

                        w.append(i + ");\n");

                    }

                }

                w.append("    }\n");

                w.append("    @Override public void setValue(" + className + " data, int type, Object value) {\n");

                w.append("      switch (type) {\n");

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

                    final GetSet pgs = propsGetSet.get(i);

                    if (pgs.readOnly) {

                        continue;

                    }

                    final String set = pgs.setter;

                    String tn = pgs.type;

                    String btn = findBoxedType(tn);

                    if (btn != null) {

                        tn = btn;

                    }

                    w.append("        case " + i + ": ");

                    if (pgs.setter != null) {

                        w.append("data.").append(strip(pgs.setter)).append("(TYPE.extractValue(" + tn + ".class, value)); return;\n");

                    } else {

                        w.append("TYPE.replaceValue(data.").append(strip(pgs.getter)).append("(), " + tn + ".class, value); return;\n");

                    }

                }

                w.append("      }\n");

                w.append("      throw new UnsupportedOperationException();\n");

                w.append("    }\n");

                w.append("    @Override public Object getValue(" + className + " data, int type) {\n");

                w.append("      switch (type) {\n");

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

                    final String get = propsGetSet.get(i).getter;

                    if (get != null) {

                        w.append("        case " + i + ": return data." + strip(get) + "();\n");

                    }

                }

                w.append("      }\n");

                w.append("      throw new UnsupportedOperationException();\n");

                w.append("    }\n");

                w.append("    @Override public void call(" + className + " model, int type, Object data, Object ev) throws Exception {\n");

                w.append("      switch (type) {\n");

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

                    final String name = (String)functions.get(i);

                    final Object param = functions.get(i + 1);

                    if (param instanceof ExecutableElement) {

                        ExecutableElement ee = (ExecutableElement)param;

                        w.append("        case " + (i / 2) + ":\n");

                        w.append("          ").append(((TypeElement)e).getQualifiedName()).append(".").append(name).append("(");

                        w.append(wrapParams(ee, null, className, "model", "ev", "data"));

                        w.append(");\n");

                        w.append("          return;\n");

                    } else {

                        String call = (String)param;

                        w.append("        case " + (i / 2) + ":\n"); // model." + name + "(data, ev); return;\n");

                        w.append("          ").append(call).append("\n");

                        w.append("          return;\n");

                    }

                }

                w.append("      }\n");

                w.append("      throw new UnsupportedOperationException();\n");

                w.append("    }\n");

                w.append("    @Override public org.netbeans.html.json.spi.Proto protoFor(Object obj) {\n");

                w.append("      return ((" + className + ")obj).proto;");

                w.append("    }\n");

                w.append("    @Override public void onChange(" + className + " model, int type) {\n");

                w.append("      switch (type) {\n");

                {

                    String[] arr = functionDeps.keySet().toArray(new String[0]);

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

                        Collection<String> onChange = functionDeps.get(arr[i]);

                        if (onChange != null) {

                            w.append("      case " + i + ":\n");

                            for (String call : onChange) {

                                w.append("      ").append(call).append("\n");

                            }

                            w.write("      return;\n");

                        }

                    }

                }

                w.append("    }\n");

                w.append("      throw new UnsupportedOperationException();\n");

                w.append("    }\n");

                w.append(onReceiveType);

                w.append("    @Override public " + className + " read(net.java.html.BrwsrCtx c, Object json) { return new " + className + "(c, json); }\n");

                w.append("    @Override public " + className + " cloneTo(" + className + " o, net.java.html.BrwsrCtx c) { return o.clone(c); }\n");

                w.append("  }\n");

                w.append("  private ").append(className).append("(net.java.html.BrwsrCtx c, Object json) {\n");

                w.append("    this(c);\n");

                int values = 0;

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

                    Prprt p = findPrprt(props, propsGetSet.get(i).name);

                    if (p == null) {

                        continue;

                    }

                    values++;

                }

                w.append("    Object[] ret = new Object[" + values + "];\n");

                w.append("    proto.extract(json, new String[] {\n");

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

                    Prprt p = findPrprt(props, propsGetSet.get(i).name);

                    if (p == null) {

                        continue;

                    }

                    w.append("      \"").append(propsGetSet.get(i).name).append("\",\n");

                }

                w.append("    }, ret);\n");

                for (int i = 0, cnt = 0, prop = 0; i < propsGetSet.size(); i++) {

                    final String pn = propsGetSet.get(i).name;

                    Prprt p = findPrprt(props, pn);

                    if (p == null || prop >= props.length) {

                        continue;

                    }

                    boolean[] isModel = { false };

                    boolean[] isEnum = { false };

                    boolean isPrimitive[] = { false };

                    String type = checkType(props[prop++], isModel, isEnum, isPrimitive);

                    if (p.array()) {

                        w.append("    if (ret[" + cnt + "] instanceof Object[]) {\n");

                        w.append("      for (Object e : ((Object[])ret[" + cnt + "])) {\n");

                        if (isModel[0]) {

                            w.append("        this.prop_").append(pn).append(".add(proto.read");

                            w.append("(" + type + ".class, e));\n");

                        } else if (isEnum[0]) {

                            w.append("        this.prop_").append(pn);

                            w.append(".add(e == null ? null : ");

                            w.append(type).append(".valueOf(TYPE.stringValue(e)));\n");

                        } else {

                            if (isPrimitive(type)) {

                                w.append("        this.prop_").append(pn).append(".add(TYPE.numberValue(e).");

                                w.append(type).append("Value());\n");

                            } else {

                                w.append("        this.prop_").append(pn).append(".add((");

                                w.append(type).append(")e);\n");

                            }

                        }

                        w.append("      }\n");

                        w.append("    }\n");

                    } else {

                        if (isEnum[0]) {

                            w.append("    try {\n");

                            w.append("    this.prop_").append(pn);

                            w.append(" = ret[" + cnt + "] == null ? null : ");

                            w.append(type).append(".valueOf(TYPE.stringValue(ret[" + cnt + "]));\n");

                            w.append("    } catch (IllegalArgumentException ex) {\n");

                            w.append("      ex.printStackTrace();\n");

                            w.append("    }\n");

                        } else if (isPrimitive(type)) {

                            w.append("    this.prop_").append(pn);

                            w.append(" = ret[" + cnt + "] == null ? ");

                            if ("char".equals(type)) {

                                w.append("0 : (TYPE.charValue(");

                            } else if ("boolean".equals(type)) {

                                w.append("false : (TYPE.boolValue(");

                            } else {

                                w.append("0 : (TYPE.numberValue(");

                            }

                            w.append("ret[" + cnt + "])).");

                            w.append(type).append("Value();\n");

                        } else if (isModel[0]) {

                            w.append("    this.prop_").append(pn).append(" = proto.read");

                            w.append("(" + type + ".class, ");

                            w.append("ret[" + cnt + "]);\n");

                        }else {

                            w.append("    this.prop_").append(pn);

                            w.append(" = (").append(type).append(')');

                            w.append("ret[" + cnt + "];\n");

                        }

                    }

                    cnt++;

                }

                w.append("  }\n");

                writeToString(props, w);

                writeClone(className, props, w);

                w.write("  /** Activates this model instance in the current {@link \n"

                    + "net.java.html.json.Models#bind(java.lang.Object, net.java.html.BrwsrCtx) browser context}. \n"

                    + "In case of using Knockout technology, this means to \n"

                    + "bind JSON like data in this model instance with Knockout tags in \n"

                    + "the surrounding HTML page.\n"

                    + "*/\n"

                );

                w.write("  public " + className + " applyBindings() {\n");

                w.write("    proto.applyBindings();\n");

                w.write("    return this;\n");

                w.write("  }\n");

                w.write("  public boolean equals(Object o) {\n");

                w.write("    if (o == this) return true;\n");

                w.write("    if (!(o instanceof " + className + ")) return false;\n");

                w.write("    " + className + " p = (" + className + ")o;\n");

                for (Prprt p : props) {

                    w.write("    if (!TYPE.isSame(prop_" + p.name() + ", p.prop_" + p.name() + ")) return false;\n");

                }

                w.write("    return true;\n");

                w.write("  }\n");

                w.write("  public int hashCode() {\n");

                w.write("    int h = " + className + ".class.getName().hashCode();\n");

                for (Prprt p : props) {

                    w.write("    h = TYPE.hashPlus(prop_" + p.name() + ", h);\n");

                }

                w.write("    return h;\n");

                w.write("  }\n");

                w.write("}\n");

            } finally {

                w.close();

            }

        } catch (IOException ex) {

            error("Can't create " + className + ".java", e);

            return false;

        }

        return ok;

    }

    private boolean generateProperties(

        Element where,

        Writer w, String className, Prprt[] properties,

        List<GetSet> props, 

        Map<String,Collection<String[]>> deps,

        Map<String,Collection<String>> functionDeps

    ) throws IOException {

        boolean ok = true;

        for (Prprt p : properties) {

            final String tn;

            tn = typeName(where, p);

            String[] gs = toGetSet(p.name(), tn, p.array());

            String castTo;

            if (p.array()) {

                w.write("  private final java.util.List<" + tn + "> prop_" + p.name() + ";\n");

                castTo = "java.util.List";

                w.write("  public java.util.List<" + tn + "> " + gs[0] + "() {\n");

                w.write("    proto.accessProperty(\"" + p.name() + "\");\n");

                w.write("    return prop_" + p.name() + ";\n");

                w.write("  }\n");

            } else {

                castTo = tn;

                w.write("  private " + tn + " prop_" + p.name() + ";\n");

                w.write("  public " + tn + " " + gs[0] + "() {\n");

                w.write("    proto.accessProperty(\"" + p.name() + "\");\n");

                w.write("    return prop_" + p.name() + ";\n");

                w.write("  }\n");

                w.write("  public void " + gs[1] + "(" + tn + " v) {\n");

                w.write("    proto.verifyUnlocked();\n");

                w.write("    if (TYPE.isSame(prop_" + p.name() + ", v)) return;\n");

                w.write("    Object o = prop_" + p.name() + ";\n");

                w.write("    prop_" + p.name() + " = v;\n");

                w.write("    proto.valueHasMutated(\"" + p.name() + "\", o, v);\n");

                {

                    Collection<String[]> dependants = deps.get(p.name());

                    if (dependants != null) {

                        for (String[] pair : dependants) {

                            w.write("    proto.valueHasMutated(\"" + pair[0] + "\", null, " + pair[1] + "());\n"); 

                        }

                    }

                }

                {

                    Collection<String> dependants = functionDeps.get(p.name());

                    if (dependants != null) {

                        w.append(className).append(" model = ").append(className).append(".this;\n");

                        for (String call : dependants) {

                            w.append("  ").append(call);

                        }

                    }

                }

                w.write("  }\n");

            }

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

                if (props.get(i).name.equals(p.name())) {

                    error("Cannot have the name " + p.name() + " defined twice", where);

                    ok = false;

                }

            }

            props.add(new GetSet(

                p.name(),

                gs[2],

                gs[3],

                tn,

                gs[3] == null && !p.array()

            ));

        }

        return ok;

    }

    private boolean generateComputedProperties(

        Writer w, Prprt[] fixedProps,

        Collection<? extends Element> arr, Collection<GetSet> props,

        Map<String,Collection<String[]>> deps

    ) throws IOException {

        boolean ok = true;

        for (Element e : arr) {

            if (e.getKind() != ElementKind.METHOD) {

                continue;

            }

            final ComputedProperty cp = e.getAnnotation(ComputedProperty.class);

            final Transitive tp = e.getAnnotation(Transitive.class);

            if (cp == null) {

                continue;

            }

            if (!e.getModifiers().contains(Modifier.STATIC)) {

                error("Method " + e.getSimpleName() + " has to be static when annotated by @ComputedProperty", e);

                ok = false;

                continue;

            }

            ExecutableElement ee = (ExecutableElement)e;

            final TypeMirror rt = ee.getReturnType();

            final Types tu = processingEnv.getTypeUtils();

            TypeMirror ert = tu.erasure(rt);

            String tn = fqn(ert, ee);

            boolean array = false;

            final TypeMirror toCheck;

            if (tn.equals("java.util.List")) {

                array = true;

                toCheck = ((DeclaredType)rt).getTypeArguments().get(0);

            } else {

                toCheck = rt;

            }

            final String sn = ee.getSimpleName().toString();

            if (toCheck.getKind().isPrimitive()) {

                // OK

            } else {

                TypeMirror stringType = processingEnv.getElementUtils().getTypeElement("java.lang.String").asType();

                TypeMirror enumType = processingEnv.getElementUtils().getTypeElement("java.lang.Enum").asType();

                if (tu.isSubtype(toCheck, stringType)) {

                    // OK

                } else if (tu.isSubtype(tu.erasure(toCheck), tu.erasure(enumType))) {

                    // OK

                } else if (isModel(toCheck)) {

                    // OK

                } else {

                    try {

                        tu.unboxedType(toCheck);

                        // boxed types are OK

                    } catch (IllegalArgumentException ex) {

                        ok = false;

                        error(sn + " cannot return " + toCheck, e);

                    }

                }

            }

            String[] gs = toGetSet(sn, tn, array);

            w.write("  public " + tn);

            if (array) {

                w.write("<" + toCheck + ">");

            }

            w.write(" " + gs[0] + "() {\n");

            int arg = 0;

            boolean deep = false;

            for (VariableElement pe : ee.getParameters()) {

                final String dn = pe.getSimpleName().toString();

                if (!verifyPropName(pe, dn, fixedProps)) {

                    ok = false;

                }

                final TypeMirror pt = pe.asType();

                if (isModel(pt)) {

                    deep = true;

                }

                final String dt = fqn(pt, ee);

                if (dt.startsWith("java.util.List") && pt instanceof DeclaredType) {

                    final List<? extends TypeMirror> ptArgs = ((DeclaredType)pt).getTypeArguments();

                    if (ptArgs.size() == 1 && isModel(ptArgs.get(0))) {

                        deep = true;

                    }

                }

                String[] call = toGetSet(dn, dt, false);

                w.write("    " + dt + " arg" + (++arg) + " = ");

                w.write(call[0] + "();\n");

                Collection<String[]> depends = deps.get(dn);

                if (depends == null) {

                    depends = new LinkedHashSet<String[]>();

                    deps.put(dn, depends);

                }

                depends.add(new String[] { sn, gs[0] });

            }

            w.write("    try {\n");

            if (tp != null) {

                deep = tp.deep();

            }

            if (deep) {

                w.write("      proto.acquireLock(\"" + sn + "\");\n");

            } else {

                w.write("      proto.acquireLock();\n");

            }

            w.write("      return " + fqn(ee.getEnclosingElement().asType(), ee) + '.' + e.getSimpleName() + "(");

            String sep = "";

            for (int i = 1; i <= arg; i++) {

                w.write(sep);

                w.write("arg" + i);

                sep = ", ";

            }

            w.write(");\n");

            w.write("    } finally {\n");

            w.write("      proto.releaseLock();\n");

            w.write("    }\n");

            w.write("  }\n");

            props.add(new GetSet(

                e.getSimpleName().toString(),

                gs[2],

                null,

                tn,

                true

            ));

        }

        return ok;

    }

    private static String[] toGetSet(String name, String type, boolean array) {

        String n = Character.toUpperCase(name.charAt(0)) + name.substring(1);

        String bck2brwsrType = "L" + type.replace('.', '_') + "_2";

        if ("int".equals(type)) {

            bck2brwsrType = "I";

        }

        if ("double".equals(type)) {

            bck2brwsrType = "D";

        }

        String pref = "get";

        if ("boolean".equals(type)) {

            pref = "is";

            bck2brwsrType = "Z";

        }

        final String nu = n.replace('.', '_');

        if (array) {

            return new String[] { 

                "get" + n,

                null,

                "get" + nu + "__Ljava_util_List_2",

                null

            };

        }

        return new String[]{

            pref + n, 

            "set" + n, 

            pref + nu + "__" + bck2brwsrType,

            "set" + nu + "__V" + bck2brwsrType

        };

    }

    private String typeName(Element where, Prprt p) {

        String ret;

        boolean[] isModel = { false };

        boolean[] isEnum = { false };

        boolean isPrimitive[] = { false };

        ret = checkType(p, isModel, isEnum, isPrimitive);

        if (p.array()) {

            String bt = findBoxedType(ret);

            if (bt != null) {

                return bt;

            }

        }

        return ret;

    }

    private static String findBoxedType(String ret) {

        if (ret.equals("boolean")) {

            return Boolean.class.getName();

        }

        if (ret.equals("byte")) {

            return Byte.class.getName();

        }

        if (ret.equals("short")) {

            return Short.class.getName();

        }

        if (ret.equals("char")) {

            return Character.class.getName();

        }

        if (ret.equals("int")) {

            return Integer.class.getName();

        }

        if (ret.equals("long")) {

            return Long.class.getName();

        }

        if (ret.equals("float")) {

            return Float.class.getName();

        }

        if (ret.equals("double")) {

            return Double.class.getName();

        }

        return null;

    }

    private boolean verifyPropName(Element e, String propName, Prprt[] existingProps) {

        StringBuilder sb = new StringBuilder();

        String sep = "";

        for (Prprt Prprt : existingProps) {

            if (Prprt.name().equals(propName)) {

                return true;

            }

            sb.append(sep);

            sb.append('"');

            sb.append(Prprt.name());

            sb.append('"');

            sep = ", ";

        }

        error(

            propName + " is not one of known properties: " + sb

            , e

        );

        return false;

    }

    private static String findPkgName(Element e) {

        for (;;) {

            if (e.getKind() == ElementKind.PACKAGE) {

                return ((PackageElement)e).getQualifiedName().toString();

            }

            e = e.getEnclosingElement();

        }

    }

    private boolean generateFunctions(

        Element clazz, StringWriter body, String className, 

        List<? extends Element> enclosedElements, List<Object> functions

    ) {

        for (Element m : enclosedElements) {

            if (m.getKind() != ElementKind.METHOD) {

                continue;

            }

            ExecutableElement e = (ExecutableElement)m;

            Function onF = e.getAnnotation(Function.class);

            if (onF == null) {

                continue;

            }

            if (!e.getModifiers().contains(Modifier.STATIC)) {

                error("@OnFunction method needs to be static", e);

                return false;

            }

            if (e.getModifiers().contains(Modifier.PRIVATE)) {

                error("@OnFunction method cannot be private", e);

                return false;

            }

            if (e.getReturnType().getKind() != TypeKind.VOID) {

                error("@OnFunction method should return void", e);

                return false;

            }

            String n = e.getSimpleName().toString();

            functions.add(n);

            functions.add(e);

        }

        return true;

    }

    private boolean generateOnChange(Element clazz, Map<String,Collection<String[]>> propDeps,

        Prprt[] properties, String className, 

        Map<String, Collection<String>> functionDeps

    ) {

        for (Element m : clazz.getEnclosedElements()) {

            if (m.getKind() != ElementKind.METHOD) {

                continue;

            }

            ExecutableElement e = (ExecutableElement) m;

            OnPropertyChange onPC = e.getAnnotation(OnPropertyChange.class);

            if (onPC == null) {

                continue;

            }

            for (String pn : onPC.value()) {

                if (findPrprt(properties, pn) == null && findDerivedFrom(propDeps, pn).isEmpty()) {

                    error("No Prprt named '" + pn + "' in the model", clazz);

                    return false;

                }

            }

            if (!e.getModifiers().contains(Modifier.STATIC)) {

                error("@OnPrprtChange method needs to be static", e);

                return false;

            }

            if (e.getModifiers().contains(Modifier.PRIVATE)) {

                error("@OnPrprtChange method cannot be private", e);

                return false;

            }

            if (e.getReturnType().getKind() != TypeKind.VOID) {

                error("@OnPrprtChange method should return void", e);

                return false;

            }

            String n = e.getSimpleName().toString();

            for (String pn : onPC.value()) {

                StringBuilder call = new StringBuilder();

                call.append("  ").append(clazz.getSimpleName()).append(".").append(n).append("(");

                call.append(wrapPropName(e, className, "name", pn));

                call.append(");\n");

                Collection<String> change = functionDeps.get(pn);

                if (change == null) {

                    change = new ArrayList<String>();

                    functionDeps.put(pn, change);

                }

                change.add(call.toString());

                for (String dpn : findDerivedFrom(propDeps, pn)) {

                    change = functionDeps.get(dpn);

                    if (change == null) {

                        change = new ArrayList<String>();

                        functionDeps.put(dpn, change);

                    }

                    change.add(call.toString());

                }

            }

        }

        return true;

    }

    private boolean generateOperation(Element clazz, 

        StringWriter body, String className, 

        List<? extends Element> enclosedElements,

        List<Object> functions

    ) {

        for (Element m : enclosedElements) {

            if (m.getKind() != ElementKind.METHOD) {

                continue;

            }

            ExecutableElement e = (ExecutableElement)m;

            ModelOperation mO = e.getAnnotation(ModelOperation.class);

            if (mO == null) {

                continue;

            }

            if (!e.getModifiers().contains(Modifier.STATIC)) {

                error("@ModelOperation method needs to be static", e);

                return false;

            }

            if (e.getModifiers().contains(Modifier.PRIVATE)) {

                error("@ModelOperation method cannot be private", e);

                return false;

            }

            if (e.getReturnType().getKind() != TypeKind.VOID) {

                error("@ModelOperation method should return void", e);

                return false;

            }

            List<String> args = new ArrayList<String>();

            {

                body.append("  public void ").append(m.getSimpleName()).append("(");

                String sep = "";

                boolean checkFirst = true;

                for (VariableElement ve : e.getParameters()) {

                    final TypeMirror type = ve.asType();

                    CharSequence simpleName;

                    if (type.getKind() == TypeKind.DECLARED) {

                        simpleName = ((DeclaredType)type).asElement().getSimpleName();

                    } else {

                        simpleName = type.toString();

                    }

                    if (checkFirst && simpleName.toString().equals(className)) {

                        checkFirst = false;

                    } else {

                        if (checkFirst) {

                            error("First parameter of @ModelOperation method must be " + className, m);

                            return false;

                        }

                        args.add(ve.getSimpleName().toString());

                        body.append(sep).append("final ");

                        body.append(ve.asType().toString()).append(" ");

                        body.append(ve.toString());

                        sep = ", ";

                    }

                }

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

                int idx = functions.size() / 2;

                functions.add(m.getSimpleName().toString());

                body.append("    proto.runInBrowser(" + idx);

                for (String s : args) {

                    body.append(", ").append(s);

                }

                body.append(");\n");