package davmail;

import davmail.caldav.CaldavServer;
import davmail.exchange.ExchangeSessionFactory;
import davmail.http.DavGatewayHttpClientFacade;
import davmail.http.DavGatewaySSLProtocolSocketFactory;
import davmail.ldap.LdapServer;
import davmail.pop.PopServer;
import davmail.smtp.SmtpServer;
import davmail.ui.tray.DavGatewayTray;
import davmail.imap.ImapServer;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.BindException;
import java.util.ArrayList;

/**
 * DavGateway main class
 */
public class DavGateway {
    private static final String HTTP_DAVMAIL_SOURCEFORGE_NET_VERSION_TXT = "http://davmail.sourceforge.net/version.txt";

    private DavGateway() {
    }

    private static final ArrayList<AbstractServer> serverList = new ArrayList<AbstractServer>();

    /**
     * Start the gateway, listen on spécified smtp and pop3 ports
     *
     * @param args command line parameter config file path
     */
    public static void main(String[] args) {

        if (args.length >= 1) {
            Settings.setConfigFilePath(args[0]);
        }

        Settings.load();
        DavGatewayTray.init();

        start();
    }

    public static void start() {
        // register custom SSL Socket factory
        DavGatewaySSLProtocolSocketFactory.register();

        // prepare HTTP connection pool
        DavGatewayHttpClientFacade.start();

        int smtpPort = Settings.getIntProperty("davmail.smtpPort");
        if (smtpPort != 0) {
            serverList.add(new SmtpServer(smtpPort));
        }
        int popPort = Settings.getIntProperty("davmail.popPort");
        if (popPort != 0) {
            serverList.add(new PopServer(popPort));
        }
        int imapPort = Settings.getIntProperty("davmail.imapPort");
        if (imapPort != 0) {
            serverList.add(new ImapServer(imapPort));
        }
        int caldavPort = Settings.getIntProperty("davmail.caldavPort");
        if (caldavPort != 0) {
            serverList.add(new CaldavServer(caldavPort));
        }
        int ldapPort = Settings.getIntProperty("davmail.ldapPort");
        if (ldapPort != 0) {
            serverList.add(new LdapServer(ldapPort));
        }

        StringBuilder message = new StringBuilder();
        StringBuilder errorMessage = new StringBuilder();
        message.append(BundleMessage.format("LOG_DAVMAIL_GATEWAY_LISTENING"));
        for (AbstractServer server : serverList) {
            try {
                server.bind();
                server.start();
                message.append(' ').append(BundleMessage.format("LOG_PROTOCOL_PORT", server.getProtocolName(), server.getPort()));
            } catch (BindException e) {
                errorMessage.append(' ').append(BundleMessage.format("LOG_PROTOCOL_PORT", server.getProtocolName(), server.getPort()));
            } catch (IOException e) {
                errorMessage.append(' ').append(BundleMessage.format("LOG_PROTOCOL_PORT", server.getProtocolName(), server.getPort()));
            }
        }

        DavGatewayTray.info(message.toString());
        if (errorMessage.length() > 0) {
            DavGatewayTray.error(new BundleMessage("LOG_SOCKET_BIND_FAILED", errorMessage.toString()));
        }

        // check for new version
        String releasedVersion = getReleasedVersion();
        String currentVersion = getCurrentVersion();
        if (currentVersion != null && releasedVersion != null && currentVersion.compareTo(releasedVersion) < 0) {
            DavGatewayTray.info(new BundleMessage("LOG_NEW_VERSION_AVAILABLE", releasedVersion));
        }

    }

    public static void stop() {
        for (AbstractServer server:serverList) {
            server.close();
            try {
                server.join();
            } catch (InterruptedException e) {
                DavGatewayTray.warn(new BundleMessage("LOG_EXCEPTION_WAITING_SERVER_THREAD_DIE"), e);
            }
        }
        // close pooled connections
        DavGatewayHttpClientFacade.stop();
        // clear session cache
        ExchangeSessionFactory.reset();
    }

    public static String getCurrentVersion() {
        Package davmailPackage = DavGateway.class.getPackage();
        return davmailPackage.getImplementationVersion();
    }

    public static String getReleasedVersion() {
        String version = null;
        BufferedReader versionReader = null;
        HttpClient httpClient = DavGatewayHttpClientFacade.getInstance();
        GetMethod getMethod = new GetMethod(HTTP_DAVMAIL_SOURCEFORGE_NET_VERSION_TXT);
        try {
            httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(1000);
            int status = httpClient.executeMethod(getMethod);
            if (status == HttpStatus.SC_OK) {
                versionReader = new BufferedReader(new InputStreamReader(getMethod.getResponseBodyAsStream()));
                version = versionReader.readLine();
            }
        } catch (IOException e) {
            DavGatewayTray.debug(new BundleMessage("LOG_UNABLE_TO_GET_RELEASED_VERSION"));
        } finally {
            if (versionReader != null) {
                try {
                    versionReader.close();
                } catch (IOException e) {
                    // ignore
                }
            }
            getMethod.releaseConnection();
        }
        return version;
    }
}