/**
 * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
 */

package net.sourceforge.pmd.lang.java.rule.strings;

import java.util.List;

import net.sourceforge.pmd.lang.java.ast.ASTAdditiveExpression;
import net.sourceforge.pmd.lang.java.ast.ASTAllocationExpression;
import net.sourceforge.pmd.lang.java.ast.ASTArrayDimsAndInits;
import net.sourceforge.pmd.lang.java.ast.ASTClassOrInterfaceType;
import net.sourceforge.pmd.lang.java.ast.ASTExpression;
import net.sourceforge.pmd.lang.java.ast.ASTName;
import net.sourceforge.pmd.lang.java.rule.AbstractJavaRule;
import net.sourceforge.pmd.lang.java.symboltable.TypedNameDeclaration;
import net.sourceforge.pmd.lang.java.typeresolution.TypeHelper;
import net.sourceforge.pmd.lang.symboltable.NameDeclaration;

public class StringInstantiationRule extends AbstractJavaRule {

    @Override
    public Object visit(ASTAllocationExpression node, Object data) {
        if (!(node.jjtGetChild(0) instanceof ASTClassOrInterfaceType)) {
            return data;
        }

        if (!TypeHelper.isA((ASTClassOrInterfaceType) node.jjtGetChild(0), String.class)) {
            return data;
        }

        List<ASTExpression> exp = node.findDescendantsOfType(ASTExpression.class);
        if (exp.size() >= 2) {
            return data;
        }

        if (node.hasDecendantOfAnyType(ASTArrayDimsAndInits.class, ASTAdditiveExpression.class)) {
            return data;
        }

        ASTName name = node.getFirstDescendantOfType(ASTName.class);
        // Literal, i.e., new String("foo")
        if (name == null) {
            addViolation(data, node);
            return data;
        }

        NameDeclaration nd = name.getNameDeclaration();
        if (nd == null) {
            return data;
        }

        if (nd instanceof TypedNameDeclaration && TypeHelper.isA((TypedNameDeclaration) nd, String.class)) {
            addViolation(data, node);
        }
        return data;
    }
}