package gudusoft.gsqlparser.util;

import gudusoft.gsqlparser.TCustomSqlStatement;
import gudusoft.gsqlparser.nodes.TObjectName;
import gudusoft.gsqlparser.nodes.TParseTreeVisitor;

import java.util.ArrayList;

public class THelp {

    public static ArrayList<TObjectName> getObjectNames(TCustomSqlStatement sqlStatement){
        ArrayList<TObjectName> columns = new ArrayList<>();
        columnVisitor visitor = new columnVisitor();
        visitor.setColumns(columns);
        sqlStatement.acceptChildren(visitor);
        return visitor.getColumns() ;
    }

}

class columnVisitor extends TParseTreeVisitor {
    ArrayList<TObjectName> columns;

    public void setColumns(ArrayList<TObjectName> columns) {
        this.columns = columns;
    }

    public ArrayList<TObjectName> getColumns() {
        return columns;
    }

    public void preVisit(TObjectName node){
        switch (node.getDbObjectType()){
            case column:
                columns.add(node);
                break;
            default:
                break;
        }
    }
}