package jaskell.sql;

import jaskell.script.Directive;

import jaskell.script.Parameter;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.util.List;

import java.util.Objects;

public abstract class Statement implements Directive {

public PreparedStatement prepare(Connection connection) throws SQLException {

return connection.prepareStatement(this.script());

}

public boolean execute(Connection connection) throws SQLException, IllegalStateException {

try(PreparedStatement statement = connection.prepareStatement(this.script())) {

syncParameters(statement);

return statement.execute();

}

}

public boolean execute(PreparedStatement statement) throws SQLException, IllegalStateException {

syncParameters(statement);

return statement.execute();

}

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

boolean flag = false;

for (Parameter<?> parameter:parameters()) {

if (Objects.equals(parameter.key(), key)) {

if(parameter.valueClass().isInstance(value)) {

@SuppressWarnings("unchecked")

Parameter<T> p = (Parameter<T>) parameter;

p.value(value);

} else {

throw new IllegalArgumentException(String.format("parameter %s typed %s but received %s",

parameter.key(), parameter.valueClass().getName(), value.getClass().getName()));

}

flag = true;

}

}

if(!flag){

throw new IllegalArgumentException(String.format("parameter named %s not found", key));

}

return this;

}

public void clear(PreparedStatement statement) throws SQLException {

statement.clearParameters();

}

public void syncParameters(PreparedStatement statement) throws SQLException {

List<Parameter<?>> parameters = parameters();

for (Parameter<?> parameter: parameters){

if(!parameter.confirmed()){

throw new IllegalStateException(String.format("parameter %s has not value", parameter.key()));

}

}

clear(statement);

List<Parameter<?>> params = parameters();

setOrder(params);

for (Parameter<?> parameter: params) {

//TODO: overload by parameter.valueClass

statement.setObject(parameter.order(), parameter.value());

}

}

void setOrder(List<Parameter<?>> parameters){

for (int i = 0; i < parameters.size(); i++) {

parameters.get(i).order(i+1);

}

}

public Returning returning(String names){

Returning re = new Returning(names);

re._prefix = this;

return re;

}

public Returning returning(String ... names){

Returning re = new Returning(names);

re._prefix = this;

return re;

}

public Returning returning(Directive names){

Returning re = new Returning(names);

re._prefix = this;

return re;

}

public Statement cache(){

Statement self = this;

return new Statement() {

private final String _script = self.script();

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

@Override

public String script() {

return _script;

}

@Override

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

return _parameters;

}

};

}

}