package com.rjconsultores.ventaboletos;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.apache.log4j.Logger;
import org.flywaydb.core.Flyway;

import javax.sql.DataSource;

public class FlyWay {
	private static Logger log = Logger.getLogger(FlyWay.class);
	
	private static final FlyWay INSTANCE = new FlyWay();
	
	private DataSource dataSource = null;
	private String location = "db.migration";
	
	public static FlyWay getInstance() {
		return INSTANCE;
	}
	
	public void defineLocation(final String location) {
		this.location = location;
	}
	
	public void defineDataSource(final DataSource dataSource) {
		this.dataSource = dataSource;
		
		fixFiles(dataSource);
	}
	
	private void fixFiles(final DataSource ds) {
		try {
			Connection c = dataSource.getConnection();
			Statement s = c.createStatement();

			fixVersion(s, "20161710.1833", "20161017.1833", "V20161017_1833__mantis8112.sql");
			fixVersion(s, "20161910.0934", "20161019.0934", "V20161019_0934__mantis7907.sql");
			fixVersion(s, "20162410.1119", "20161024.1119", "V20161024_1119__mantis7904.sql");

			s.close();
			
		} catch (SQLException e) {
			log.error(e.getMessage(), e);
		}
	}

	private void fixVersion(final Statement s, final String oldVersion, final String newVersion, final String newScript) throws SQLException {
		ResultSet rs = s.executeQuery("select count(*) as total from \"schema_version\" where \"version\" like '" + oldVersion + "'");
		
		int total = 0;
		
		while (rs.next()) {
			total = rs.getInt("total");
		}
		
		rs.close();
		
		if (total > 0) {
			log.info("Fix version " + oldVersion + " to new version " + newVersion + " and new script " + newScript);

			StringBuilder sql = new StringBuilder("");
			sql.append(" update \"schema_version\"");
			sql.append(" set \"version\" = '" + newVersion + "', \"script\" = '" + newScript + "'");
			sql.append(" where \"version\" like '" + oldVersion + "'");
			
			s.executeUpdate(sql.toString());
		}
	}

	public boolean start() {
		log.info("Executando Flyway...");
		
		try{
			final Flyway flyway = new Flyway();
	
			flyway.setLocations(this.location);
			flyway.setDataSource(dataSource);
			
			execute(flyway);

		}catch(Throwable t){
			log.error("Erro ao executar o flyway",t);
			
			return false;
		}
		
		log.info("Flyway executado.");
		
		return true;
	}

	public boolean start(String url, String user, String password) {
		log.info("Executando Flyway...");
		
		try{
			final Flyway flyway = new Flyway();
	
			flyway.setLocations("classpath: " + this.location);
			flyway.setDataSource(url, user, password);
			
			execute(flyway);
			
		}catch(Throwable t){
			log.error("Erro ao executar o flyway",t);
			
			return false;
		}
		
		log.info("Flyway executado.");
		
		return true;
	}

	public void execute(final Flyway flyway) {
		flyway.setValidateOnMigrate(false);
		flyway.setIgnoreFutureMigrations(true);
		flyway.setOutOfOrder(true);
		flyway.setBaselineOnMigrate(true);

		flyway.migrate();
	}
}