package jaskell.sql;

import jaskell.parsec.Option;

import jaskell.script.Directive;

import jaskell.script.Parameter;

import java.sql.*;

import java.util.List;

import java.util.Optional;

public abstract class Query extends Statement implements CouldLimit, CouldOffset, CouldUnion {

public Union union(){

Union re = new Union();

re._prefix = this;

return re;

}

public Union union(Query query){

Union re = new Union();

re._prefix = this;

re._query = query;

return re;

}

public Limit limit(int l){

Limit re = new Limit(l);

re._prefix = this;

return re;

}

public Limit limit(Directive l){

Limit re = new Limit(l);

re._prefix = this;

return re;

}

public Offset offset(int o){

Offset re = new Offset(o);

re._prefix = this;

return re;

}

public Offset offset(Directive o){

Offset re = new Offset(o);

re._prefix = this;

return re;

}

public <T> Query setParameter(Object key, T value) throws IllegalArgumentException {

super.setParameter(key, value);

return this;

}

public ResultSet query(PreparedStatement statement) throws SQLException {

syncParameters(statement);

return statement.executeQuery();

}

public Optional scalar(Connection conn) throws SQLException {

try(PreparedStatement statement = conn.prepareStatement(this.script());

ResultSet resultSet = statement.executeQuery()){

if (resultSet.next()){

if(resultSet.getObject(1)!=null) {

return Optional.of(resultSet.getObject(1));

}

}

return Optional.empty();

}

}

public <T> Optional<T> scalar(Connection conn, Class<T> cls) throws SQLException {

try(PreparedStatement statement = conn.prepareStatement(this.script());

ResultSet resultSet = statement.executeQuery()){

if (resultSet.next()){

if(resultSet.getObject(1)!=null) {

return Optional.of(cls.cast(resultSet.getObject(1)));

}

}

return Optional.empty();

}

}

public Query cache(){

Query self = this;

return new Query() {

private String _script = self.script();

private List<Parameter<?>> _parameters = self.parameters();

@Override

public String script() {

return _script;

}

@Override

public List<Parameter<?>> parameters() {

return _parameters;

}

};

}

}