package org.keycloak.email.freemarker;

import org.jboss.logging.Logger;
import org.keycloak.email.EmailException;
import org.keycloak.email.EmailProvider;
import org.keycloak.freemarker.ExtendingThemeManager;
import org.keycloak.freemarker.FreeMarkerUtil;
import org.keycloak.freemarker.Theme;
import org.keycloak.models.RealmModel;
import org.keycloak.models.UserModel;
import org.keycloak.provider.ProviderSession;

import javax.mail.Message;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

/**
 * @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
 */
public class FreeMarkerEmailProvider implements EmailProvider {

    private static final Logger log = Logger.getLogger(FreeMarkerEmailProvider.class);

    private ProviderSession session;
    private RealmModel realm;
    private UserModel user;

    public FreeMarkerEmailProvider(ProviderSession session) {
        this.session = session;
    }

    @Override
    public EmailProvider setRealm(RealmModel realm) {
        this.realm = realm;
        return this;
    }

    @Override
    public EmailProvider setUser(UserModel user) {
        this.user = user;
        return this;
    }

    @Override
    public void sendPasswordReset(String link, long expirationInMinutes) throws EmailException {
        Map<String, Object> attributes = new HashMap<String, Object>();
        attributes.put("link", link);
        attributes.put("linkExpiration", expirationInMinutes);

        send("passwordResetSubject", "password-reset.ftl", attributes);
    }

    @Override
    public void sendVerifyEmail(String link, long expirationInMinutes) throws EmailException {
        Map<String, Object> attributes = new HashMap<String, Object>();
        attributes.put("link", link);
        attributes.put("linkExpiration", expirationInMinutes);

        send("emailVerificationSubject", "email-verification.ftl", attributes);
    }

    private void send(String subjectKey, String template, Map<String, Object> attributes) throws EmailException {
        try {
            ExtendingThemeManager themeManager = new ExtendingThemeManager(session);
            Theme theme = themeManager.createTheme(realm.getAccountTheme(), Theme.Type.EMAIL);

            String subject =  theme.getMessages().getProperty(subjectKey);
            String body = FreeMarkerUtil.processTemplate(attributes, template, theme);

            send(subject, body);
        } catch (Exception e) {
            throw new EmailException("Failed to template email", e);
        }
    }


    private void send(String subject, String body) throws EmailException {
        try {
            String address = user.getEmail();
            Map<String, String> config = realm.getSmtpConfig();

            Properties props = new Properties();
            props.setProperty("mail.smtp.host", config.get("host"));

            boolean auth = "true".equals(config.get("auth"));
            boolean ssl = "true".equals(config.get("ssl"));
            boolean starttls = "true".equals(config.get("starttls"));

            if (config.containsKey("port")) {
                props.setProperty("mail.smtp.port", config.get("port"));
            }

            if (auth) {
                props.put("mail.smtp.auth", "true");
            }

            if (ssl) {
                props.put("mail.smtp.socketFactory.port", config.get("port"));
                props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
            }

            if (starttls) {
                props.put("mail.smtp.starttls.enable", "true");
            }

            String from = config.get("from");

            Session session = Session.getInstance(props);

            Message msg = new MimeMessage(session);
            msg.setFrom(new InternetAddress(from));
            msg.setHeader("To", address);
            msg.setSubject(subject);
            msg.setText(body);
            msg.saveChanges();

            Transport transport = session.getTransport("smtp");
            if (auth) {
                transport.connect(config.get("user"), config.get("password"));
            } else {
                transport.connect();
            }
            transport.sendMessage(msg, new InternetAddress[]{new InternetAddress(address)});
        } catch (Exception e) {
            log.warn("Failed to send email", e);
            throw new EmailException(e);
        }
    }

    @Override
    public void close() {
    }

}
