/*
 * Copyright (c) 2003, 2019, 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.javac.code;

import java.util.LinkedHashMap;
import java.util.Map;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.AnnotationValueVisitor;
import javax.lang.model.type.DeclaredType;
import com.sun.tools.javac.code.Symbol.*;
import com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.DefinedBy.Api;

An annotation value.
 
This is NOT part of any supported API.
 If you write code that depends on this, you do so at your own risk.
 This code and its internal interfaces are subject to change or
 deletion without notice.
/** An annotation value.
 *
 *  <p><b>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 */
public abstract class Attribute implements AnnotationValue {

    
The type of the annotation element. /** The type of the annotation element. */
    public Type type;

    public Attribute(Type type) {
        this.type = type;
    }

    public abstract void accept(Visitor v);

    @DefinedBy(Api.LANGUAGE_MODEL)
    public Object getValue() {
        throw new UnsupportedOperationException();
    }

    @DefinedBy(Api.LANGUAGE_MODEL)
    public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
        throw new UnsupportedOperationException();
    }

    public boolean isSynthesized() {
        return false;
    }

    public TypeAnnotationPosition getPosition() { return null; }

    
The value for an annotation element of primitive type or String. /** The value for an annotation element of primitive type or String. */
    public static class Constant extends Attribute {
        public final Object value;
        public void accept(Visitor v) { v.visitConstant(this); }
        public Constant(Type type, Object value) {
            super(type);
            this.value = value;
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            return Constants.format(value, type);
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public Object getValue() {
            return Constants.decode(value, type);
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            if (value instanceof String)
                return v.visitString((String) value, p);
            if (value instanceof Integer) {
                int i = (Integer) value;
                switch (type.getTag()) {
                case BOOLEAN:   return v.visitBoolean(i != 0, p);
                case CHAR:      return v.visitChar((char) i, p);
                case BYTE:      return v.visitByte((byte) i, p);
                case SHORT:     return v.visitShort((short) i, p);
                case INT:       return v.visitInt(i, p);
                }
            }
            switch (type.getTag()) {
            case LONG:          return v.visitLong((Long) value, p);
            case FLOAT:         return v.visitFloat((Float) value, p);
            case DOUBLE:        return v.visitDouble((Double) value, p);
            }
            throw new AssertionError("Bad annotation element value: " + value);
        }
    }

    
The value for an annotation element of type java.lang.Class,
 represented as a ClassSymbol.
/** The value for an annotation element of type java.lang.Class,
     *  represented as a ClassSymbol.
     */
    public static class Class extends Attribute {
        public final Type classType;
        public void accept(Visitor v) { v.visitClass(this); }
        public Class(Types types, Type type) {
            super(makeClassType(types, type));
            this.classType = type;
        }
        static Type makeClassType(Types types, Type type) {
            Type arg = type.isPrimitive()
                ? types.boxedClass(type).type
                : types.erasure(type);
            return new Type.ClassType(types.syms.classType.getEnclosingType(),
                                      List.of(arg),
                                      types.syms.classType.tsym);
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            return classType + ".class";
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public Type getValue() {
            return classType;
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            return v.visitType(classType, p);
        }
    }

    
A compound annotation element value, the type of which is an
 attribute interface.
/** A compound annotation element value, the type of which is an
     *  attribute interface.
     */
    public static class Compound extends Attribute implements AnnotationMirror {
        
The attributes values, as pairs.  Each pair contains a
 reference to the accessing method in the attribute interface
 and the value to be returned when that method is called to
 access this attribute.
/** The attributes values, as pairs.  Each pair contains a
         *  reference to the accessing method in the attribute interface
         *  and the value to be returned when that method is called to
         *  access this attribute.
         */
        public final List<Pair<MethodSymbol,Attribute>> values;
        public TypeAnnotationPosition position;

        private boolean synthesized = false;

        @Override
        public boolean isSynthesized() {
            return synthesized;
        }

        public void setSynthesized(boolean synthesized) {
            this.synthesized = synthesized;
        }

        public Compound(Type type,
                        List<Pair<MethodSymbol,Attribute>> values,
                        TypeAnnotationPosition position) {
            super(type);
            this.values = values;
            this.position = position;
        }

        public Compound(Type type,
                        List<Pair<MethodSymbol,Attribute>> values) {
            this(type, values, null);
        }

        @Override
        public TypeAnnotationPosition getPosition() {
            if (hasUnknownPosition()) {
                if (values.size() != 0) {
                    Name valueName = values.head.fst.name.table.names.value;
                    Pair<MethodSymbol, Attribute> res = getElemPair(valueName);
                    position = res == null ? null : res.snd.getPosition();
                }
            }
            return position;
        }

        public boolean isContainerTypeCompound() {
            if (isSynthesized() && values.size() == 1)
                return getFirstEmbeddedTC() != null;
            return false;
        }

        private Compound getFirstEmbeddedTC() {
            if (values.size() == 1) {
                Pair<MethodSymbol, Attribute> val = values.get(0);
                if (val.fst.getSimpleName().contentEquals("value")
                        && val.snd instanceof Array) {
                    Array arr = (Array) val.snd;
                    if (arr.values.length != 0
                            && arr.values[0] instanceof Attribute.TypeCompound)
                        return (Attribute.TypeCompound) arr.values[0];
                }
            }
            return null;
        }

        public boolean tryFixPosition() {
            if (!isContainerTypeCompound())
                return false;

            Compound from = getFirstEmbeddedTC();
            if (from != null && from.position != null &&
                    from.position.type != TargetType.UNKNOWN) {
                position = from.position;
                return true;
            }
            return false;
        }

        public boolean hasUnknownPosition() {
            return position.type == TargetType.UNKNOWN;
        }

        public void accept(Visitor v) { v.visitCompound(this); }

        
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.
/**
         * Returns a string representation of this annotation.
         * String is of one of the forms:
         * <pre>
         *     {@code @com.example.foo(name1=val1, name2=val2)}
         *     {@code @com.example.foo(val)}
         *     {@code @com.example.foo}
         * </pre>
         * Omit parens for marker annotations, and omit "value=" when allowed.
         */
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            StringBuilder buf = new StringBuilder();
            buf.append("@");
            buf.append(type);
            int len = values.length();
            if (len > 0) {
                buf.append('(');
                boolean first = true;
                for (Pair<MethodSymbol, Attribute> value : values) {
                    if (!first)
                        buf.append(", ");
                    first = false;

                    Name name = value.fst.name;
                    if (len > 1 || name != name.table.names.value) {
                        buf.append(name);
                        buf.append('=');
                    }
                    buf.append(value.snd);
                }
                buf.append(')');
            }
            return buf.toString();
        }

        public Attribute member(Name member) {
            Pair<MethodSymbol,Attribute> res = getElemPair(member);
            return res == null ? null : res.snd;
        }

        private Pair<MethodSymbol, Attribute> getElemPair(Name member) {
            for (Pair<MethodSymbol,Attribute> pair : values)
                if (pair.fst.name == member) return pair;
            return null;
        }

        @DefinedBy(Api.LANGUAGE_MODEL)
        public Attribute.Compound getValue() {
            return this;
        }

        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            return v.visitAnnotation(this, p);
        }

        @DefinedBy(Api.LANGUAGE_MODEL)
        public DeclaredType getAnnotationType() {
            return (DeclaredType) type;
        }

        @DefinedBy(Api.LANGUAGE_MODEL)
        public Map<MethodSymbol, Attribute> getElementValues() {
            Map<MethodSymbol, Attribute> valmap = new LinkedHashMap<>();
            for (Pair<MethodSymbol, Attribute> value : values)
                valmap.put(value.fst, value.snd);
            return valmap;
        }
    }

    public static class TypeCompound extends Compound {
        public TypeCompound(Compound compound,
                             TypeAnnotationPosition position) {
            super(compound.type, compound.values, position);
        }

        public TypeCompound(Type type,
                             List<Pair<MethodSymbol,Attribute>> values,
                             TypeAnnotationPosition position) {
            super(type, values, position);
        }
    }

    
The value for an annotation element of an array type.
/** The value for an annotation element of an array type.
     */
    public static class Array extends Attribute {
        public final Attribute[] values;
        public Array(Type type, Attribute[] values) {
            super(type);
            this.values = values;
        }

        public Array(Type type, List<Attribute> values) {
            super(type);
            this.values = values.toArray(new Attribute[values.size()]);
        }

        public void accept(Visitor v) { v.visitArray(this); }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            StringBuilder buf = new StringBuilder();
            buf.append('{');
            boolean first = true;
            for (Attribute value : values) {
                if (!first)
                    buf.append(", ");
                first = false;
                buf.append(value);
            }
            buf.append('}');
            return buf.toString();
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public List<Attribute> getValue() {
            return List.from(values);
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            return v.visitArray(getValue(), p);
        }

        @Override
        public TypeAnnotationPosition getPosition() {
            if (values.length != 0)
                return values[0].getPosition();
            else
                return null;
        }
    }

    
The value for an annotation element of an enum type.
/** The value for an annotation element of an enum type.
     */
    public static class Enum extends Attribute {
        public VarSymbol value;
        public Enum(Type type, VarSymbol value) {
            super(type);
            this.value = Assert.checkNonNull(value);
        }
        public void accept(Visitor v) { v.visitEnum(this); }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            return value.toString();
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public VarSymbol getValue() {
            return value;
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            return v.visitEnumConstant(value, p);
        }
    }

    public static class Error extends Attribute {
        public Error(Type type) {
            super(type);
        }
        public void accept(Visitor v) { v.visitError(this); }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String toString() {
            return "<error>";
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public String getValue() {
            return toString();
        }
        @DefinedBy(Api.LANGUAGE_MODEL)
        public <R, P> R accept(AnnotationValueVisitor<R, P> v, P p) {
            return v.visitString(toString(), p);
        }
    }

    public static class UnresolvedClass extends Error {
        public Type classType;
        public UnresolvedClass(Type type, Type classType) {
            super(type);
            this.classType = classType;
        }
    }

    
A visitor type for dynamic dispatch on the kind of attribute value. /** A visitor type for dynamic dispatch on the kind of attribute value. */
    public static interface Visitor {
        void visitConstant(Attribute.Constant value);
        void visitClass(Attribute.Class clazz);
        void visitCompound(Attribute.Compound compound);
        void visitArray(Attribute.Array array);
        void visitEnum(Attribute.Enum e);
        void visitError(Attribute.Error e);
    }

    
A mirror of java.lang.annotation.RetentionPolicy. /** A mirror of java.lang.annotation.RetentionPolicy. */
    public static enum RetentionPolicy {
        SOURCE,
        CLASS,
        RUNTIME
    }
}