/*
 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.codemodel.internal;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.Collections;
import java.util.Collection;

import com.sun.codemodel.internal.util.ClassNameComparator;

/**
 * Java method.
 */
public class JMethod extends JGenerifiableImpl implements JDeclaration, JAnnotatable, JDocCommentable {

        /**
         * Modifiers for this method
         */
        private JMods mods;

        /**
         * Return type for this method
         */
        private JType type = null;

        /**
         * Name of this method
         */
        private String name = null;

        /**
         * List of parameters for this method's declaration
         */
        private final List<JVar> params = new ArrayList<JVar>();

        /**
         * Set of exceptions that this method may throw.
     * A set instance lazily created.
         */
        private Set<JClass> _throws;

        /**
         * JBlock of statements that makes up the body this method
         */
        private JBlock body = null;

        private JDefinedClass outer;

        /**
         * javadoc comments for this JMethod
         */
        private JDocComment jdoc = null;

        /**
         * Variable parameter for this method's varargs declaration
         * introduced in J2SE 1.5
         */
        private JVar varParam = null;

    /**
     * Annotations on this variable. Lazily created.
     */
    private List<JAnnotationUse> annotations = null;


        private boolean isConstructor() {
                return type == null;
        }

    /** To set the default value for the
     *  annotation member
     */
    private JExpression defaultValue = null;


        /**
         * JMethod constructor
         *
         * @param mods
         *        Modifiers for this method's declaration
         *
         * @param type
         *        Return type for the method
         *
         * @param name
         *        Name of this method
         */
        JMethod(JDefinedClass outer, int mods, JType type, String name) {
                this.mods = JMods.forMethod(mods);
                this.type = type;
                this.name = name;
                this.outer = outer;
        }

        /**
         * Constructor constructor
         *
         * @param mods
         *        Modifiers for this constructor's declaration
         *
         * @param _class
         *        JClass containing this constructor
         */
        JMethod(int mods, JDefinedClass _class) {
                this.mods = JMods.forMethod(mods);
                this.type = null;
                this.name = _class.name();
                this.outer = _class;
        }

    private Set<JClass> getThrows() {
        if(_throws==null)
            _throws = new TreeSet<JClass>(ClassNameComparator.theInstance);
        return _throws;
    }

        /**
         * Add an exception to the list of exceptions that this
         * method may throw.
         *
         * @param exception
         *        Name of an exception that this method may throw
         */
        public JMethod _throws(JClass exception) {
        getThrows().add(exception);
                return this;
        }

        public JMethod _throws(Class<? extends Throwable> exception) {
                return _throws(outer.owner().ref(exception));
        }

        /**
         * Returns the list of variable of this method.
         *
         * @return List of parameters of this method. This list is not modifiable.
         */
        public List<JVar> params() {
                return Collections.<JVar>unmodifiableList(params);
        }

        /**
         * Add the specified variable to the list of parameters
         * for this method signature.
         *
         * @param type
         *        JType of the parameter being added
         *
         * @param name
         *        Name of the parameter being added
         *
         * @return New parameter variable
         */
        public JVar param(int mods, JType type, String name) {
                JVar v = new JVar(JMods.forVar(mods), type, name, null);
                params.add(v);
                return v;
        }

        public JVar param(JType type, String name) {
                return param(JMod.NONE, type, name);
        }

        public JVar param(int mods, Class<?> type, String name) {
                return param(mods, outer.owner()._ref(type), name);
        }

        public JVar param(Class<?> type, String name) {
                return param(outer.owner()._ref(type), name);
        }

        /**
         * @see #varParam(JType, String)
         */
        public JVar varParam(Class<?> type, String name) {
        return varParam(outer.owner()._ref(type),name);
    }

    /**
     * Add the specified variable argument to the list of parameters
     * for this method signature.
     *
     * @param type
     *      Type of the parameter being added.
     *
     * @param name
     *        Name of the parameter being added
     *
     * @return the variable parameter
     *
     * @throws IllegalStateException
     *      If this method is called twice.
     *      varargs in J2SE 1.5 can appear only once in the
     *      method signature.
     */
    public JVar varParam(JType type, String name) {
                if (!hasVarArgs()) {

            varParam =
                                new JVar(
                                        JMods.forVar(JMod.NONE),
                                        type.array(),
                                        name,
                                        null);
                        return varParam;
                } else {
                        throw new IllegalStateException(
                                "Cannot have two varargs in a method,\n"
                                        + "Check if varParam method of JMethod is"
                                        + " invoked more than once");

                }

        }

    /**
     * Adds an annotation to this variable.
     * @param clazz
     *          The annotation class to annotate the field with
     */
    public JAnnotationUse annotate(JClass clazz){
        if(annotations==null)
           annotations = new ArrayList<JAnnotationUse>();
        JAnnotationUse a = new JAnnotationUse(clazz);
        annotations.add(a);
        return a;
    }

    /**
     * Adds an annotation to this variable.
     *
     * @param clazz
     *          The annotation class to annotate the field with
     */
    public JAnnotationUse annotate(Class <? extends Annotation> clazz){
        return annotate(owner().ref(clazz));
    }

    public <W extends JAnnotationWriter> W annotate2(Class<W> clazz) {
        return TypedAnnotationWriter.create(clazz,this);
    }

    public Collection<JAnnotationUse> annotations() {
        if (annotations == null)
            annotations = new ArrayList<JAnnotationUse>();
        return Collections.unmodifiableList(annotations);
    }

    /**
         * Check if there are any varargs declared
         * for this method signature.
         */
        public boolean hasVarArgs() {
                return this.varParam!=null;
        }

        public String name() {
                return name;
        }

    /**
     * Changes the name of the method.
     */
    public void name(String n) {
        this.name = n;
    }

    /**
         * Returns the return type.
         */
        public JType type() {
                return type;
        }

    /**
     * Overrides the return type.
     */
    public void type(JType t) {
        this.type = t;
    }

    /**
         * Returns all the parameter types in an array.
         * @return
         *      If there's no parameter, an empty array will be returned.
         */
        public JType[] listParamTypes() {
                JType[] r = new JType[params.size()];
                for (int i = 0; i < r.length; i++)
                        r[i] = params.get(i).type();
                return r;
        }

        /**
         * Returns  the varags parameter type.
         * @return
         * If there's no vararg parameter type, null will be returned.
         */
        public JType listVarParamType() {
                if (varParam != null)
                        return varParam.type();
                else
                        return null;
        }

        /**
         * Returns all the parameters in an array.
         * @return
         *      If there's no parameter, an empty array will be returned.
         */
        public JVar[] listParams() {
                return params.toArray(new JVar[params.size()]);
        }

        /**
         * Returns the variable parameter
         * @return
         *      If there's no parameter, null will be returned.
         */
        public JVar listVarParam() {
                return varParam;
        }

        /**
         * Returns true if the method has the specified signature.
         */
        public boolean hasSignature(JType[] argTypes) {
                JVar[] p = listParams();
                if (p.length != argTypes.length)
                        return false;

                for (int i = 0; i < p.length; i++)
                        if (!p[i].type().equals(argTypes[i]))
                                return false;

                return true;
        }

        /**
         * Get the block that makes up body of this method
         *
         * @return Body of method
         */
        public JBlock body() {
                if (body == null)
                        body = new JBlock();
                return body;
        }

    /**
     * Specify the default value for this annotation member
     * @param value
     *           Default value for the annotation member
     *
     */
    public void declareDefaultValue(JExpression value){
        this.defaultValue = value;
    }

        /**
         * Creates, if necessary, and returns the class javadoc for this
         * JDefinedClass
         *
         * @return JDocComment containing javadocs for this class
         */
        public JDocComment javadoc() {
                if (jdoc == null)
                        jdoc = new JDocComment(owner());
                return jdoc;
        }

        public void declare(JFormatter f) {
                if (jdoc != null)
                        f.g(jdoc);

        if (annotations != null){
            for (JAnnotationUse a : annotations)
                f.g(a).nl();
        }

        f.g(mods);

        // declare the generics parameters
                super.declare(f);

                if (!isConstructor())
                        f.g(type);
                f.id(name).p('(').i();
        // when parameters are printed in new lines, we want them to be indented.
        // there's a good chance no newlines happen, too, but just in case it does.
                boolean first = true;
        for (JVar var : params) {
            if (!first)
                f.p(',');
            if(var.isAnnotated())
                f.nl();
            f.b(var);
            first = false;
        }
                if (hasVarArgs()) {
                        if (!first)
                                f.p(',');
                        f.g(varParam.type().elementType());
                        f.p("... ");
                        f.id(varParam.name());
                }

                f.o().p(')');
                if (_throws!=null && !_throws.isEmpty()) {
                        f.nl().i().p("throws").g(_throws).nl().o();
                }

        if (defaultValue != null) {
            f.p("default ");
            f.g(defaultValue);
        }
                if (body != null) {
                        f.s(body);
                } else if (
                        !outer.isInterface() && !outer.isAnnotationTypeDeclaration() && !mods.isAbstract() && !mods.isNative()) {
                        // Print an empty body for non-native, non-abstract methods
                        f.s(new JBlock());
                } else {
                        f.p(';').nl();
                }
        }

    /**
     * @return
     *      the current modifiers of this method.
     *      Always return non-null valid object.
     */
    public JMods mods() {
        return mods;
    }

    /**
     * @deprecated use {@link #mods()}
     */
    public JMods getMods() {
                return mods;
        }

        protected JCodeModel owner() {
                return outer.owner();
        }
}
