/*

 * Copyright (c) 1999, 2012, 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 com.sun.source.tree.Tree.Kind;

import javax.lang.model.type.TypeKind;

/** An interface for type tag values, which distinguish between different

 *  sorts of types.

 *

 *  <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 enum TypeTag {

    /** The tag of the basic type `byte'.

     */

    BYTE(1),

    /** The tag of the basic type `char'.

     */

    CHAR(2),

    /** The tag of the basic type `short'.

     */

    SHORT(3),

    /** The tag of the basic type `int'.

     */

    INT(4),

    /** The tag of the basic type `long'.

     */

    LONG(5),

    /** The tag of the basic type `float'.

     */

    FLOAT(6),

    /** The tag of the basic type `double'.

     */

    DOUBLE(7),

    /** The tag of the basic type `boolean'.

     */

    BOOLEAN,

    /** The tag of the type `void'.

     */

    VOID,

    /** The tag of all class and interface types.

     */

    CLASS,

    /** The tag of all array types.

     */

    ARRAY,

    /** The tag of all (monomorphic) method types.

     */

    METHOD,

    /** The tag of all package "types".

     */

    PACKAGE,

    /** The tag of all (source-level) type variables.

     */

    TYPEVAR,

    /** The tag of all type arguments.

     */

    WILDCARD,

    /** The tag of all polymorphic (method-) types.

     */

    FORALL,

    /** The tag of deferred expression types in method context

     */

    DEFERRED,

    /** The tag of the bottom type {@code <null>}.

     */

    BOT,

    /** The tag of a missing type.

     */

    NONE,

    /** The tag of the error type.

     */

    ERROR,

    /** The tag of an unknown type

     */

    UNKNOWN,

    /** The tag of all instantiatable type variables.

     */

    UNDETVAR,

    /** Pseudo-types, these are special tags

     */

    UNINITIALIZED_THIS,

    UNINITIALIZED_OBJECT;

    /** This field will only be used for tags related with numeric types for

     *  optimization reasons.

     */

    private TypeTag(int order) {

        this.order = order;

    }

    private static final int MIN_NUMERIC_TAG_ORDER = 1;

    private static final int MAX_NUMERIC_TAG_ORDER = 7;

    /** Returns the number of type tags.

     */

    public static int getTypeTagCount() {

        // last two tags are not included in the total as long as they are pseudo-types

        return (UNDETVAR.ordinal() + 1);

    }

    public boolean isSubRangeOf(TypeTag range) {

        return (this == range) || isStrictSubRangeOf(range);

    }

    public boolean isStrictSubRangeOf(TypeTag range) {

        if (this.order >= MIN_NUMERIC_TAG_ORDER && this.order <= MAX_NUMERIC_TAG_ORDER &&

            range.order >= MIN_NUMERIC_TAG_ORDER && this.order <= MAX_NUMERIC_TAG_ORDER) {

            if (this == range)

                return false;

            switch (this) {

                case BYTE:

                    return true;

                case CHAR: case SHORT: case INT:

                case LONG: case FLOAT:

                    return this.order < range.order && range.order <= MAX_NUMERIC_TAG_ORDER;

                default:

                    return false;

            }

        }

        else

            return false;

    }

    public Kind getKindLiteral() {

        switch (this) {

        case INT:

            return Kind.INT_LITERAL;

        case LONG:

            return Kind.LONG_LITERAL;

        case FLOAT:

            return Kind.FLOAT_LITERAL;

        case DOUBLE:

            return Kind.DOUBLE_LITERAL;

        case BOOLEAN:

            return Kind.BOOLEAN_LITERAL;

        case CHAR:

            return Kind.CHAR_LITERAL;

        case CLASS:

            return Kind.STRING_LITERAL;

        case BOT:

            return Kind.NULL_LITERAL;

        default:

            throw new AssertionError("unknown literal kind " + this);

        }

    }

    public TypeKind getPrimitiveTypeKind() {

        switch (this) {

        case BOOLEAN:

            return TypeKind.BOOLEAN;

        case BYTE:

            return TypeKind.BYTE;

        case SHORT:

            return TypeKind.SHORT;

        case INT:

            return TypeKind.INT;

        case LONG:

            return TypeKind.LONG;

        case CHAR:

            return TypeKind.CHAR;

        case FLOAT:

            return TypeKind.FLOAT;

        case DOUBLE:

            return TypeKind.DOUBLE;

        case VOID:

            return TypeKind.VOID;

        default:

            throw new AssertionError("unknown primitive type " + this);

        }

    }

}