/*
 * Copyright (c) 2003, 2011, 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.tools.javadoc;


import com.sun.javadoc.*;

import com.sun.tools.javac.code.Attribute;
import com.sun.tools.javac.code.Symbol.*;
import com.sun.tools.javac.util.List;
import com.sun.tools.javac.util.Pair;


/**
 * Represents an annotation.
 * An annotation associates a value with each element of an annotation type.
 * Sure it ought to be called "Annotation", but that clashes with
 * java.lang.annotation.Annotation.
 *
 * @author Scott Seligman
 * @since 1.5
 */

public class AnnotationDescImpl implements AnnotationDesc {

    private final DocEnv env;
    private final Attribute.Compound annotation;


    AnnotationDescImpl(DocEnv env, Attribute.Compound annotation) {
        this.env = env;
        this.annotation = annotation;
    }

    /**
     * Returns the annotation type of this annotation.
     */
    public AnnotationTypeDoc annotationType() {
        ClassSymbol atsym = (ClassSymbol)annotation.type.tsym;
        if (annotation.type.isErroneous()) {
            env.warning(null, "javadoc.class_not_found", annotation.type.toString());
            return new AnnotationTypeDocImpl(env, atsym);
        } else {
            return (AnnotationTypeDoc)env.getClassDoc(atsym);
        }
    }

    /**
     * Returns this annotation's elements and their values.
     * Only those explicitly present in the annotation are
     * included, not those assuming their default values.
     * Returns an empty array if there are none.
     */
    public ElementValuePair[] elementValues() {
        List<Pair<MethodSymbol,Attribute>> vals = annotation.values;
        ElementValuePair res[] = new ElementValuePair[vals.length()];
        int i = 0;
        for (Pair<MethodSymbol,Attribute> val : vals) {
            res[i++] = new ElementValuePairImpl(env, val.fst, val.snd);
        }
        return res;
    }

    /**
     * Returns a string representation of this annotation.
     * String is of one of the forms:
     *     @com.example.foo(name1=val1, name2=val2)
     *     @com.example.foo(val)
     *     @com.example.foo
     * Omit parens for marker annotations, and omit "value=" when allowed.
     */
    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder("@");
        sb.append(annotation.type.tsym);

        ElementValuePair vals[] = elementValues();
        if (vals.length > 0) {          // omit parens for marker annotation
            sb.append('(');
            boolean first = true;
            for (ElementValuePair val : vals) {
                if (!first) {
                    sb.append(", ");
                }
                first = false;

                String name = val.element().name();
                if (vals.length == 1 && name.equals("value")) {
                    sb.append(val.value());
                } else {
                    sb.append(val);
                }
            }
            sb.append(')');
        }
        return sb.toString();
    }


    /**
     * Represents an association between an annotation type element
     * and one of its values.
     */
    public static class ElementValuePairImpl implements ElementValuePair {

        private final DocEnv env;
        private final MethodSymbol meth;
        private final Attribute value;

        ElementValuePairImpl(DocEnv env, MethodSymbol meth, Attribute value) {
            this.env = env;
            this.meth = meth;
            this.value = value;
        }

        /**
         * Returns the annotation type element.
         */
        public AnnotationTypeElementDoc element() {
            return env.getAnnotationTypeElementDoc(meth);
        }

        /**
         * Returns the value associated with the annotation type element.
         */
        public AnnotationValue value() {
            return new AnnotationValueImpl(env, value);
        }

        /**
         * Returns a string representation of this pair
         * of the form "name=value".
         */
        @Override
        public String toString() {
            return meth.name + "=" + value();
        }
    }
}
