/*

 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;

import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;

import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;

import com.sun.org.apache.bcel.internal.generic.Instruction;

import com.sun.org.apache.bcel.internal.generic.InstructionList;

import com.sun.org.apache.bcel.internal.generic.NEW;

import com.sun.org.apache.bcel.internal.generic.PUSH;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;

import java.util.List;

/**

 * @author Jacek Ambroziak

 * @author Santiago Pericas-Geertsen

 * @LastModified: Oct 2017

 */

final class ConcatCall extends FunctionCall {

    public ConcatCall(QName fname, List<Expression> arguments) {

        super(fname, arguments);

    }

    public Type typeCheck(SymbolTable stable) throws TypeCheckError {

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

            final Expression exp = argument(i);

            if (!exp.typeCheck(stable).identicalTo(Type.String)) {

                setArgument(i, new CastExpr(exp, Type.String));

            }

        }

        return _type = Type.String;

    }

    /** translate leaves a String on the stack */

    public void translate(ClassGenerator classGen, MethodGenerator methodGen) {

        final ConstantPoolGen cpg = classGen.getConstantPool();

        final InstructionList il = methodGen.getInstructionList();

        final int nArgs = argumentCount();

        switch (nArgs) {

        case 0:

            il.append(new PUSH(cpg, EMPTYSTRING));

            break;

        case 1:

            argument().translate(classGen, methodGen);

            break;

        default:

            final int initBuffer = cpg.addMethodref(STRING_BUFFER_CLASS,

                                                    "<init>", "()V");

            final Instruction append =

                new INVOKEVIRTUAL(cpg.addMethodref(STRING_BUFFER_CLASS,

                                                   "append",

                                                   "("+STRING_SIG+")"

                                                   +STRING_BUFFER_SIG));

            final int toString = cpg.addMethodref(STRING_BUFFER_CLASS,

                                                  "toString",

                                                  "()"+STRING_SIG);

            il.append(new NEW(cpg.addClass(STRING_BUFFER_CLASS)));

            il.append(DUP);

            il.append(new INVOKESPECIAL(initBuffer));

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

                argument(i).translate(classGen, methodGen);

                il.append(append);

            }

            il.append(new INVOKEVIRTUAL(toString));

        }

    }

}