/*
 * Copyright 2009-2010 MBTE Sweden AB.
 *
 * Licensed 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 org.mbte.groovypp.compiler.transformers;

import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.expr.*;
import org.codehaus.groovy.syntax.Token;
import org.codehaus.groovy.syntax.Types;
import org.mbte.groovypp.compiler.CompilerTransformer;
import org.mbte.groovypp.compiler.TypeUtil;
import org.mbte.groovypp.compiler.bytecode.BytecodeExpr;
import org.mbte.groovypp.runtime.Format;
import org.objectweb.asm.MethodVisitor;

import java.util.List;

import static org.codehaus.groovy.ast.ClassHelper.make;

public class GStringExpressionTransformer extends ExprTransformer<GStringExpression> {
    public static final ClassNode FORMAT = make(Format.class);

    public Expression transform(final GStringExpression exp, CompilerTransformer compiler) {

        final List<Expression> values = exp.getValues();
        final List<ConstantExpression> strings = exp.getStrings();

        boolean hasClosures = false;
        for(Expression e : values) {
            if(e instanceof ClosureExpression) {
                hasClosures = true;
                break;
            }
        }

        if(hasClosures) {
            final List list = exp.getValues();
            for (int i = 0; i != list.size(); i++)
               list.set(i, compiler.transform((Expression) list.get(i)));
            return new BytecodeExpr (exp, ClassHelper.GSTRING_TYPE) {
                protected void compile(MethodVisitor mv) {
                    mv.visitTypeInsn(NEW, "org/codehaus/groovy/runtime/GStringImpl");
                    mv.visitInsn(DUP);

                    int size = exp.getValues().size();
                    mv.visitLdcInsn(size);
                    mv.visitTypeInsn(ANEWARRAY, "java/lang/Object");

                    for (int i = 0; i < size; i++) {
                        mv.visitInsn(DUP);
                        mv.visitLdcInsn(i);
                        final BytecodeExpr el = (BytecodeExpr) exp.getValue(i);
                        el.visit(mv);
                        box(el.getType(), mv);
                        mv.visitInsn(AASTORE);
                    }

                    List strings = exp.getStrings();
                    size = strings.size();
                    mv.visitLdcInsn(size);
                    mv.visitTypeInsn(ANEWARRAY, "java/lang/String");

                    for (int i = 0; i < size; i++) {
                        mv.visitInsn(DUP);
                        mv.visitLdcInsn(i);
                        mv.visitLdcInsn(((ConstantExpression) strings.get(i)).getValue());
                        mv.visitInsn(AASTORE);
                    }

                    mv.visitMethodInsn(INVOKESPECIAL, "org/codehaus/groovy/runtime/GStringImpl", "<init>", "([Ljava/lang/Object;[Ljava/lang/String;)V");
                }
            };
        }
        else {
            int n = strings.size();

            Expression acc = new ConstructorCallExpression(TypeUtil.STRING_BUILDER, new ArgumentListExpression());
            acc.setSourcePosition(exp);
            for (int i = 0; i != n; ++i) {

                acc = new MethodCallExpression(acc, "append", new ArgumentListExpression(strings.get(i)));
                acc.setSourcePosition(exp);

                if (i < values.size()) {
                    acc = new StaticMethodCallExpression(FORMAT, "toString", new ArgumentListExpression(values.get(i), acc));
                    acc.setSourcePosition(exp);
                }
            }
            acc = new MethodCallExpression(acc, "toString", new ArgumentListExpression());
            acc.setSourcePosition(exp);
            return compiler.transform(acc);
        }
    }
}