/*

 * Copyright 2009 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.tools.javac.code;

import javax.lang.model.element.ElementKind;

import com.sun.tools.javac.code.Symbol.VarSymbol;

import com.sun.tools.javac.tree.JCTree;

import com.sun.tools.javac.tree.TreeInfo;

import com.sun.tools.javac.tree.TreeScanner;

import com.sun.tools.javac.tree.JCTree.*;

import com.sun.tools.javac.util.Context;

import com.sun.tools.javac.util.List;

import com.sun.tools.javac.util.ListBuffer;

/**

 * Contains operations specific to processing type annotations

 */

public class TypeAnnotations {

    private static final Context.Key<TypeAnnotations> key

        = new Context.Key<TypeAnnotations>();

    public static TypeAnnotations instance(Context context) {

        TypeAnnotations instance = context.get(key);

        if (instance == null)

            instance = new TypeAnnotations(context);

        return instance;

    }

    protected TypeAnnotations(Context context) {

        context.put(key, this);

    }

    public void taFillAndLift(JCClassDecl tree, boolean visitBodies) {

        new TypeAnnotationPositions().scan(tree);

        new TypeAnnotationLift().scan(tree);

    }

    private static class TypeAnnotationPositions extends TreeScanner {

        private ListBuffer<JCTree> frames = ListBuffer.lb();

        private void push(JCTree t) { frames = frames.prepend(t); }

        private JCTree pop() { return frames.next(); }

        private JCTree peek2() { return frames.toList().tail.head; }

        @Override

        public void scan(JCTree tree) {

            push(tree);

            super.scan(tree);

            pop();

        }

        private boolean inClass = false;

        @Override

        public void visitClassDef(JCClassDecl tree) {

           if (!inClass) {

               // Do not recurse into nested and inner classes since

               // TransTypes.visitClassDef makes an invocation for each class

               // separately.

               inClass = true;

               try {

                   super.visitClassDef(tree);

               } finally {

                   inClass = false;

               }

           }

        }

        private TypeAnnotationPosition resolveFrame(JCTree tree, JCTree frame,

                List<JCTree> path, TypeAnnotationPosition p) {

            switch (frame.getKind()) {

                case TYPE_CAST:

                    p.type = TargetType.TYPECAST;

                    p.pos = frame.pos;

                    return p;

                case INSTANCE_OF:

                    p.type = TargetType.INSTANCEOF;

                    p.pos = frame.pos;

                    return p;

                case NEW_CLASS:

                    p.type = TargetType.NEW;

                    p.pos = frame.pos;

                    return p;

                case NEW_ARRAY:

                    p.type = TargetType.NEW;

                    p.pos = frame.pos;

                    return p;

                case CLASS:

                    p.pos = frame.pos;

                    if (((JCClassDecl)frame).extending == tree) {

                        p.type = TargetType.CLASS_EXTENDS;

                        p.type_index = -1;

                    } else if (((JCClassDecl)frame).implementing.contains(tree)) {

                        p.type = TargetType.CLASS_EXTENDS;

                        p.type_index = ((JCClassDecl)frame).implementing.indexOf(tree);

                    } else if (((JCClassDecl)frame).typarams.contains(tree)) {

                        p.type = TargetType.CLASS_TYPE_PARAMETER;

                        p.parameter_index = ((JCClassDecl)frame).typarams.indexOf(tree);

                    } else

                        throw new AssertionError();

                    return p;

                case METHOD: {

                    JCMethodDecl frameMethod = (JCMethodDecl)frame;

                    p.pos = frame.pos;

                    if (frameMethod.receiverAnnotations.contains(tree))

                        p.type = TargetType.METHOD_RECEIVER;

                    else if (frameMethod.thrown.contains(tree)) {

                        p.type = TargetType.THROWS;

                        p.type_index = frameMethod.thrown.indexOf(tree);

                    } else if (((JCMethodDecl)frame).restype == tree) {

                        p.type = TargetType.METHOD_RETURN_GENERIC_OR_ARRAY;

                    } else if (frameMethod.typarams.contains(tree)) {

                        p.type = TargetType.METHOD_TYPE_PARAMETER;

                        p.parameter_index = frameMethod.typarams.indexOf(tree);

                    } else

                        throw new AssertionError();

                    return p;

                }

                case MEMBER_SELECT: {

                    JCFieldAccess fieldFrame = (JCFieldAccess)frame;

                    if ("class".contentEquals(fieldFrame.name)) {

                        p.type = TargetType.CLASS_LITERAL;

                        if (fieldFrame.selected instanceof JCAnnotatedType) {

                            p.pos = TreeInfo.typeIn(fieldFrame).pos;

                        } else if (fieldFrame.selected instanceof JCArrayTypeTree) {

                            p.pos = fieldFrame.selected.pos;

                        }

                    } else

                        throw new AssertionError();

                    return p;

                }

                case PARAMETERIZED_TYPE: {

                    TypeAnnotationPosition nextP;

                    if (((JCTypeApply)frame).clazz == tree)

                        nextP = p; // generic: RAW; noop

                    else if (((JCTypeApply)frame).arguments.contains(tree))

                        p.location = p.location.prepend(

                                ((JCTypeApply)frame).arguments.indexOf(tree));

                    else

                        throw new AssertionError();

                    List<JCTree> newPath = path.tail;

                    return resolveFrame(newPath.head, newPath.tail.head, newPath, p);

                }

                case ARRAY_TYPE: {

                    p.location = p.location.prepend(0);

                    List<JCTree> newPath = path.tail;

                    return resolveFrame(newPath.head, newPath.tail.head, newPath, p);

                }

                case TYPE_PARAMETER:

                    if (path.tail.tail.head.getTag() == JCTree.CLASSDEF) {

                        JCClassDecl clazz = (JCClassDecl)path.tail.tail.head;

                        p.type = TargetType.CLASS_TYPE_PARAMETER_BOUND;

                        p.parameter_index = clazz.typarams.indexOf(path.tail.head);

                        p.bound_index = ((JCTypeParameter)frame).bounds.indexOf(tree);

                    } else if (path.tail.tail.head.getTag() == JCTree.METHODDEF) {

                        JCMethodDecl method = (JCMethodDecl)path.tail.tail.head;

                        p.type = TargetType.METHOD_TYPE_PARAMETER_BOUND;

                        p.parameter_index = method.typarams.indexOf(path.tail.head);

                        p.bound_index = ((JCTypeParameter)frame).bounds.indexOf(tree);

                    } else

                        throw new AssertionError();

                    p.pos = frame.pos;

                    return p;

                case VARIABLE:

                    VarSymbol v = ((JCVariableDecl)frame).sym;

                    p.pos = frame.pos;

                    switch (v.getKind()) {

                        case LOCAL_VARIABLE:

                            p.type = TargetType.LOCAL_VARIABLE; break;

                        case FIELD:

                            p.type = TargetType.FIELD_GENERIC_OR_ARRAY; break;

                        case PARAMETER:

                            p.type = TargetType.METHOD_PARAMETER_GENERIC_OR_ARRAY;

                            p.parameter_index = methodParamIndex(path, frame);

                            break;

                        default: throw new AssertionError();

                    }

                    return p;

                case ANNOTATED_TYPE: {

                    List<JCTree> newPath = path.tail;

                    return resolveFrame(newPath.head, newPath.tail.head,

                            newPath, p);

                }

                case METHOD_INVOCATION: {

                    JCMethodInvocation invocation = (JCMethodInvocation)frame;

                    if (!invocation.typeargs.contains(tree))

                        throw new AssertionError("{" + tree + "} is not an argument in the invocation: " + invocation);

                    p.type = TargetType.METHOD_TYPE_ARGUMENT;

                    p.pos = invocation.pos;

                    p.type_index = invocation.typeargs.indexOf(tree);

                    return p;

                }

                case EXTENDS_WILDCARD:

                case SUPER_WILDCARD: {

                    p.type = TargetType.WILDCARD_BOUND;

                    List<JCTree> newPath = path.tail;

                    TypeAnnotationPosition wildcard =

                        resolveFrame(newPath.head, newPath.tail.head, newPath,

                                new TypeAnnotationPosition());

                    if (!wildcard.location.isEmpty())

                        wildcard.type = wildcard.type.getGenericComplement();

                    p.wildcard_position = wildcard;

                    p.pos = frame.pos;

                    return p;

                }

            }

            return p;

        }

        @Override

        public void visitApply(JCMethodInvocation tree) {

            scan(tree.meth);

            scan(tree.typeargs);

            scan(tree.args);

        }

        private void setTypeAnnotationPos(List<JCTypeAnnotation> annotations, TypeAnnotationPosition position) {

            for (JCTypeAnnotation anno : annotations) {

                anno.annotation_position = position;

                anno.attribute_field.position = position;

            }

        }

        @Override

        public void visitNewArray(JCNewArray tree) {

            findPosition(tree, tree, tree.annotations);

            int dimAnnosCount = tree.dimAnnotations.size();

            // handle annotations associated with dimentions

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

                TypeAnnotationPosition p = new TypeAnnotationPosition();

                p.type = TargetType.NEW_GENERIC_OR_ARRAY;

                p.pos = tree.pos;

                p.location = p.location.append(i);

                setTypeAnnotationPos(tree.dimAnnotations.get(i), p);

            }

            // handle "free" annotations

            int i = dimAnnosCount == 0 ? 0 : dimAnnosCount - 1;

            JCExpression elemType = tree.elemtype;

            while (elemType != null) {

                if (elemType.getTag() == JCTree.ANNOTATED_TYPE) {

                    JCAnnotatedType at = (JCAnnotatedType)elemType;

                    TypeAnnotationPosition p = new TypeAnnotationPosition();

                    p.type = TargetType.NEW_GENERIC_OR_ARRAY;

                    p.pos = tree.pos;

                    p.location = p.location.append(i);

                    setTypeAnnotationPos(at.annotations, p);

                    elemType = at.underlyingType;

                } else if (elemType.getTag() == JCTree.TYPEARRAY) {

                    ++i;

                    elemType = ((JCArrayTypeTree)elemType).elemtype;

                } else

                    break;

            }

            // find annotations locations of initializer elements

            scan(tree.elems);

        }

        @Override

        public void visitAnnotatedType(JCAnnotatedType tree) {

            findPosition(tree, peek2(), tree.annotations);

            super.visitAnnotatedType(tree);

        }

        @Override

        public void visitMethodDef(JCMethodDecl tree) {

            TypeAnnotationPosition p = new TypeAnnotationPosition();

            p.type = TargetType.METHOD_RECEIVER;

            setTypeAnnotationPos(tree.receiverAnnotations, p);

            super.visitMethodDef(tree);

        }

        @Override

        public void visitTypeParameter(JCTypeParameter tree) {

            findPosition(tree, peek2(), tree.annotations);

            super.visitTypeParameter(tree);

        }

        void findPosition(JCTree tree, JCTree frame, List<JCTypeAnnotation> annotations) {

            if (!annotations.isEmpty()) {

                TypeAnnotationPosition p =

                        resolveFrame(tree, frame, frames.toList(),

                                new TypeAnnotationPosition());

                if (!p.location.isEmpty())

                    p.type = p.type.getGenericComplement();

                setTypeAnnotationPos(annotations, p);

            }

        }

        private int methodParamIndex(List<JCTree> path, JCTree param) {

            List<JCTree> curr = path;

            if (curr.head != param)

                curr = path.tail;

            JCMethodDecl method = (JCMethodDecl)curr.tail.head;

            return method.params.indexOf(param);

        }

    }

    private static class TypeAnnotationLift extends TreeScanner {

        List<Attribute.TypeCompound> recordedTypeAnnotations = List.nil();

        boolean isInner = false;

        @Override

        public void visitClassDef(JCClassDecl tree) {

            if (isInner) {

                // tree is an inner class tree.  stop now.

                // TransTypes.visitClassDef makes an invocation for each class

                // separately.

                return;

            }

            isInner = true;

            List<Attribute.TypeCompound> prevTAs = recordedTypeAnnotations;

            recordedTypeAnnotations = List.nil();

            try {

                super.visitClassDef(tree);

            } finally {

                tree.sym.typeAnnotations = tree.sym.typeAnnotations.appendList(recordedTypeAnnotations);

                recordedTypeAnnotations = prevTAs;

            }

        }

        @Override

        public void visitMethodDef(JCMethodDecl tree) {

            List<Attribute.TypeCompound> prevTAs = recordedTypeAnnotations;

            recordedTypeAnnotations = List.nil();

            try {

                super.visitMethodDef(tree);

            } finally {

                tree.sym.typeAnnotations = tree.sym.typeAnnotations.appendList(recordedTypeAnnotations);

                recordedTypeAnnotations = prevTAs;

            }

        }

        @Override

        public void visitVarDef(JCVariableDecl tree) {

            List<Attribute.TypeCompound> prevTAs = recordedTypeAnnotations;

            recordedTypeAnnotations = List.nil();

            ElementKind kind = tree.sym.getKind();

            if (kind == ElementKind.LOCAL_VARIABLE && tree.mods.annotations.nonEmpty()) {

                // need to lift the annotations

                TypeAnnotationPosition position = new TypeAnnotationPosition();

                position.pos = tree.pos;

                position.type = TargetType.LOCAL_VARIABLE;

                for (Attribute.Compound attribute : tree.sym.attributes_field) {

                    Attribute.TypeCompound tc =

                        new Attribute.TypeCompound(attribute.type, attribute.values, position);

                    recordedTypeAnnotations = recordedTypeAnnotations.append(tc);

                }

            }

            try {

                super.visitVarDef(tree);

            } finally {

                if (kind.isField() || kind == ElementKind.LOCAL_VARIABLE)

                    tree.sym.typeAnnotations = tree.sym.typeAnnotations.appendList(recordedTypeAnnotations);

                recordedTypeAnnotations = kind.isField() ? prevTAs : prevTAs.appendList(recordedTypeAnnotations);

            }

        }

        @Override

        public void visitApply(JCMethodInvocation tree) {

            scan(tree.meth);

            scan(tree.typeargs);

            scan(tree.args);

        }

        public void visitAnnotation(JCAnnotation tree) {

            if (tree instanceof JCTypeAnnotation)

                recordedTypeAnnotations = recordedTypeAnnotations.append(((JCTypeAnnotation)tree).attribute_field);

            super.visitAnnotation(tree);

        }

    }

}