/*
 * Copyright 2004 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.apt.mirror.type;


import java.util.Collection;
import java.util.ArrayList;

import com.sun.mirror.type.*;
import com.sun.mirror.type.PrimitiveType.Kind;
import com.sun.tools.apt.mirror.AptEnv;
import com.sun.tools.javac.code.*;
import com.sun.tools.javac.util.Context;

import static com.sun.tools.javac.code.TypeTags.*;


/**
 * Utilities for constructing type objects.
 */
@SuppressWarnings("deprecation")
public class TypeMaker {

    private final AptEnv env;
    private final VoidType voidType;
    private PrimitiveType[] primTypes = new PrimitiveType[VOID];
                                                // VOID is past all prim types


    private static final Context.Key<TypeMaker> typeMakerKey =
            new Context.Key<TypeMaker>();

    public static TypeMaker instance(Context context) {
        TypeMaker instance = context.get(typeMakerKey);
        if (instance == null) {
            instance = new TypeMaker(context);
        }
        return instance;
    }

    private TypeMaker(Context context) {
        context.put(typeMakerKey, this);
        env = AptEnv.instance(context);

        voidType = new VoidTypeImpl(env);
        primTypes[BOOLEAN] = new PrimitiveTypeImpl(env, Kind.BOOLEAN);
        primTypes[BYTE]    = new PrimitiveTypeImpl(env, Kind.BYTE);
        primTypes[SHORT]   = new PrimitiveTypeImpl(env, Kind.SHORT);
        primTypes[INT]     = new PrimitiveTypeImpl(env, Kind.INT);
        primTypes[LONG]    = new PrimitiveTypeImpl(env, Kind.LONG);
        primTypes[CHAR]    = new PrimitiveTypeImpl(env, Kind.CHAR);
        primTypes[FLOAT]   = new PrimitiveTypeImpl(env, Kind.FLOAT);
        primTypes[DOUBLE]  = new PrimitiveTypeImpl(env, Kind.DOUBLE);
    }


    /**
     * Returns the TypeMirror corresponding to a javac Type object.
     */
    public TypeMirror getType(Type t) {
        if (t.isPrimitive()) {
            return primTypes[t.tag];
        }
        switch (t.tag) {
        case ERROR:     // fall through
        case CLASS:     return getDeclaredType((Type.ClassType) t);
        case WILDCARD:  return new WildcardTypeImpl(env, (Type.WildcardType) t);
        case TYPEVAR:   return new TypeVariableImpl(env, (Type.TypeVar) t);
        case ARRAY:     return new ArrayTypeImpl(env, (Type.ArrayType) t);
        case VOID:      return voidType;
        default:        throw new AssertionError();
        }
    }

    /**
     * Returns the declared type corresponding to a given ClassType.
     */
    public DeclaredType getDeclaredType(Type.ClassType t) {
        return
            hasFlag(t.tsym, Flags.ANNOTATION) ? new AnnotationTypeImpl(env, t) :
            hasFlag(t.tsym, Flags.INTERFACE)  ? new InterfaceTypeImpl(env, t) :
            hasFlag(t.tsym, Flags.ENUM)       ? new EnumTypeImpl(env, t) :
                                                new ClassTypeImpl(env, t);
    }

    /**
     * Returns a collection of types corresponding to a list of javac Type
     * objects.
     */
    public Collection<TypeMirror> getTypes(Iterable<Type> types) {
        return getTypes(types, TypeMirror.class);
    }

    /**
     * Returns a collection of types corresponding to a list of javac Type
     * objects.  The element type of the result is specified explicitly.
     */
    public <T extends TypeMirror> Collection<T> getTypes(Iterable<Type> types,
                                                         Class<T> resType) {
        ArrayList<T> res = new ArrayList<T>();
        for (Type t : types) {
            TypeMirror mir = getType(t);
            if (resType.isInstance(mir)) {
                res.add(resType.cast(mir));
            }
        }
        return res;
    }

    /**
     * Returns the string representation of a type.
     * Bounds of type variables are not included; bounds of wildcard types are.
     * Type names are qualified.
     */
    public String typeToString(Type t) {
        switch (t.tag) {
        case ARRAY:
            return typeToString(env.jctypes.elemtype(t)) + "[]";
        case CLASS:
            Type.ClassType c = (Type.ClassType) t;
            return DeclaredTypeImpl.toString(env, c);
        case WILDCARD:
            Type.WildcardType a = (Type.WildcardType) t;
            return WildcardTypeImpl.toString(env, a);
        default:
            return t.tsym.toString();
        }
    }


    /**
     * Does a symbol have a given flag?
     */
    private static boolean hasFlag(Symbol s, long flag) {
        return AptEnv.hasFlag(s, flag);
    }
}