package com.example.spring.bank.account;

import java.math.BigDecimal;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCreator;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.support.GeneratedKeyHolder;
import org.springframework.jdbc.support.KeyHolder;
import org.springframework.stereotype.Repository;

@Repository
public class JDBCAccountRepository implements AccountRepository {

	@Autowired
	private JdbcTemplate jdbcTemplate;
	
	@Override
	public Account createAccount() {
		final String INSERT_SQL = "insert into account (balance) values(0)";

		KeyHolder keyHolder = new GeneratedKeyHolder();
		jdbcTemplate.update(
		    new PreparedStatementCreator() {
		        public PreparedStatement createPreparedStatement(Connection connection) throws SQLException {
		            PreparedStatement ps =
		                connection.prepareStatement(INSERT_SQL, new String[] {"account_number"});
		            //  ps.setString(1, name);
		            return ps;
		        }
		    }, keyHolder);

		Account account = new Account();
		// keyHolder.getKey() now contains the generated key
		account.setAccountNumber(keyHolder.getKey().intValue());
		account.setBalance(new BigDecimal("0.0"));

		return account;
	}

	@Override
	public void delete(int accountNumber) {
		jdbcTemplate.update("delete from account where account_number = ?", Integer.valueOf(accountNumber));
	}

	@Override
	public List<Account> findAccountsWithLowBalance(BigDecimal lessThanAmount) {
		return this.jdbcTemplate.query( "select * from account where balance < ?", new Object[] {lessThanAmount.doubleValue()}, new AccountMapper());
	}

	@Override
	public List<Account> findAllAccounts() {
		return this.jdbcTemplate.query( "select * from account", new AccountMapper());
	}

	@Override
	public Account getAccount(int accountNumber) {
		return this.jdbcTemplate.queryForObject( "select * from account where account_number = ?", new Object[] {accountNumber}, new AccountMapper());
	}

	@Override
	public void update(Account account) {
		this.jdbcTemplate.update("update account set balance = ? where account_number = ?", account.getBalance(), account.getAccountNumber());
	}

	
	private static final class AccountMapper implements RowMapper<Account> {

	    public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
	        Account account = new Account();
	        account.setAccountNumber(rs.getInt("account_number"));
	        account.setBalance(rs.getBigDecimal("balance"));
	        return account;
	    }        
	}
}