/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project is free software: you can redistribute it and/or
    * modify it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or (at your
   * option) any later version.
   *
   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.waarp.openr66.protocol.monitoring;
  
  import com.fasterxml.jackson.databind.node.ObjectNode;
  import io.netty.bootstrap.Bootstrap;
  import io.netty.buffer.ByteBuf;
  import io.netty.buffer.Unpooled;
  import io.netty.channel.Channel;
  import io.netty.channel.ChannelFuture;
  import io.netty.channel.EventLoopGroup;
  import io.netty.handler.codec.http.DefaultHttpHeaders;
  import io.netty.handler.codec.http.DefaultHttpRequest;
  import io.netty.handler.codec.http.DefaultLastHttpContent;
  import io.netty.handler.codec.http.HttpHeaderNames;
  import io.netty.handler.codec.http.HttpHeaderValues;
  import io.netty.handler.codec.http.HttpHeaders;
  import io.netty.handler.codec.http.HttpMethod;
  import io.netty.handler.codec.http.HttpRequest;
  import io.netty.handler.codec.http.HttpVersion;
  import io.netty.handler.ssl.SslContext;
  import io.netty.handler.ssl.SslContextBuilder;
  import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
  import io.netty.util.internal.SocketUtils;
  import org.joda.time.DateTime;
  import org.waarp.common.future.WaarpFuture;
  import org.waarp.common.logging.WaarpLogger;
  import org.waarp.common.logging.WaarpLoggerFactory;
  import org.waarp.common.utility.WaarpNettyUtil;
  import org.waarp.common.utility.WaarpStringUtils;
  import org.waarp.openr66.protocol.configuration.Configuration;
  import org.waarp.openr66.protocol.http.restv2.utils.JsonUtils;
  import org.waarp.openr66.protocol.networkhandler.ssl.NetworkSslServerInitializer;
  
  import javax.net.ssl.SSLException;
  import java.io.Closeable;
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.net.URI;
  import java.net.URISyntaxException;
  
  import static org.waarp.openr66.protocol.configuration.Configuration.*;
  
  /**
   * HttpMonitoringExporterClient used by the MonitorExporterTransfers
   */
  public class HttpMonitoringExporterClient implements Closeable {
    private static final WaarpLogger logger =
        WaarpLoggerFactory.getLogger(HttpMonitoringExporterClient.class);
    public static final String HTTPS = "https";
    public static final String BASIC = "Basic ";
    public static final String BEARER = "Bearer ";
    public static final String API_KEY = "ApiKey ";
  
    private final URI finalUri;
    private final String host;
    private final boolean keepConnection;
    private final Bootstrap bootstrap;
    private int port;
    private final String basicAuthent;
    private final String token;
    private final String apiKey;
    private Channel remoteRestChannel = null;
  
    private WaarpFuture futurePost = null;
  
    /**
     * Note that only one among (basicAuthent, token, apikey) is allowed and
     * will be taken into account.
     *
     * @param remoteBaseUrl as 'http://myhost.com:8080' or 'https://myhost.com:8443'
     * @param basicAuthent Basic Authent in Base64 format to connect to
     *     REST API if any (Basic authentication from 'username:paswwd')
     *     (nullable)
     * @param token access token (Bearer Token authorization
     *     by Header) (nullable)
     * @param apiKey API Key (Base64 of 'apiId:apiKey') (ApiKey authorization
     *     by Header) (nullable)
     * @param endpoint as '/waarpr66monitor' or simply '/'
     * @param keepConnection True to keep the connexion opened, False to release the connexion each time
     * @param group the EventLoopGroup to use
    */
   public HttpMonitoringExporterClient(final String remoteBaseUrl,
                                       final String basicAuthent,
                                       final String token, final String apiKey,
                                       final String endpoint,
                                       final boolean keepConnection,
                                       final EventLoopGroup group) {
     this.keepConnection = keepConnection;
     this.token = token;
     this.basicAuthent = basicAuthent;
     this.apiKey = apiKey;
     final String uri;
     if (remoteBaseUrl.endsWith("/")) {
       uri = remoteBaseUrl + endpoint;
     } else {
       uri = remoteBaseUrl + "/" + endpoint;
     }
 
     try {
       finalUri = new URI(uri);
     } catch (final URISyntaxException e) {
       logger.error("URI syntax error: {}", e.getMessage());
       throw new IllegalArgumentException(e);
     }
     final String scheme =
         finalUri.getScheme() == null? "http" : finalUri.getScheme();
     host = finalUri.getHost() == null? "127.0.0.1" : finalUri.getHost();
     port = finalUri.getPort();
     if (port == -1) {
       if ("http".equalsIgnoreCase(scheme)) {
         port = 80;
       } else if (HTTPS.equalsIgnoreCase(scheme)) {
         port = 443;
       }
     }
 
     if (!"http".equalsIgnoreCase(scheme) && !HTTPS.equalsIgnoreCase(scheme)) {
       logger.error("Only HTTP(S) is supported.");
       throw new IllegalArgumentException("Only HTTP(S) is supported.");
     }
 
     final boolean ssl = HTTPS.equalsIgnoreCase(scheme);
     final SslContext sslCtx;
     if (ssl) {
       try {
         sslCtx = SslContextBuilder.forClient().keyManager(
             NetworkSslServerInitializer.getWaarpSecureKeyStore()
                                        .getKeyManagerFactory()).trustManager(
             InsecureTrustManagerFactory.INSTANCE).build();
       } catch (final SSLException e) {
         logger.error("SslContext error", e);
         throw new IllegalArgumentException(e);
       }
     } else {
       sslCtx = null;
     }
 
     // Configure the client.
     bootstrap = new Bootstrap();
     WaarpNettyUtil.setBootstrap(bootstrap, group,
                                 (int) Configuration.configuration.getTimeoutCon(),
                                 configuration.getBlockSize() + 64, true);
     bootstrap.handler(
         new HttpMonitoringExporterClientInitializer(sslCtx, this));
   }
 
   /**
    * @param monitoredTransfers the Json objet to push as POST
    * @param start the DateTime for the 'from' interval
    * @param stop the DateTime for the 'to' interval
    * @param serverId the serverId that is sending this monitoring information
    *
    * @return True if the POST succeeded
    */
   public final boolean post(final ObjectNode monitoredTransfers,
                             final DateTime start, final DateTime stop,
                             final String serverId) {
     logger.debug("Start Post from {} to {} as {}", start, stop, serverId);
     if (keepConnection && remoteRestChannel != null &&
         !remoteRestChannel.isActive()) {
       remoteRestChannel.close();
       remoteRestChannel = null;
     }
     if (remoteRestChannel == null) {
       final ChannelFuture future =
           bootstrap.connect(SocketUtils.socketAddress(host, port));
       try {
         remoteRestChannel = future.sync().channel();
       } catch (final InterruptedException e) {//NOSONAR
         logger.error(e);
         return false;
       }
     }
     futurePost = new WaarpFuture(true);
     // Prepare Body
     final String body = JsonUtils.nodeToString(monitoredTransfers);
     final int length;
     final byte[] bbody;
     try {
       bbody = body.getBytes(WaarpStringUtils.UTF_8);
       length = body.length();
     } catch (final UnsupportedEncodingException e) {
       logger.error(e.getMessage());
       return false;
     }
     final ByteBuf buf = Unpooled.wrappedBuffer(bbody);
     final HttpHeaders headers = new DefaultHttpHeaders(true);
     // Header set
     headers.set(HttpHeaderNames.HOST, host);
     if (keepConnection) {
       headers.set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);
     } else {
       headers.set(HttpHeaderNames.CONNECTION, HttpHeaderValues.CLOSE);
     }
     if (basicAuthent != null) {
       headers.set(HttpHeaderNames.AUTHORIZATION, BASIC + basicAuthent);
     } else if (token != null) {
       headers.set(HttpHeaderNames.AUTHORIZATION, BEARER + token);
     } else if (apiKey != null) {
       headers.set(HttpHeaderNames.AUTHORIZATION, API_KEY + apiKey);
     }
     headers.set(MonitorExporterTransfers.HEADER_WAARP_ID, serverId);
     headers.set(MonitorExporterTransfers.HEADER_WAARP_START,
                 start == null? "" : start.toString());
     headers.set(MonitorExporterTransfers.HEADER_WAARP_STOP, stop.toString());
     headers.set(HttpHeaderNames.CONTENT_LENGTH, length);
     headers.set(HttpHeaderNames.CONTENT_TYPE,
                 HttpHeaderValues.APPLICATION_JSON);
     final HttpRequest request =
         new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.POST,
                                finalUri.toASCIIString(), headers);
     // Body set
     logger.debug("Request from {} to {} as {} length {}", start, stop, serverId,
                  length);
     logger.debug("{} {} {} {}", request.method(), request.uri(),
                  request.protocolVersion(), request.headers());
     remoteRestChannel.write(request);
     remoteRestChannel.write(buf);
     remoteRestChannel.writeAndFlush(DefaultLastHttpContent.EMPTY_LAST_CONTENT)
                      .awaitUninterruptibly();
     logger.debug("Ending Post from {} to {} as {}", start, stop, serverId);
 
     if (!keepConnection) {
       try {
         logger.debug("Wait for Close connection");
         remoteRestChannel.closeFuture().sync();
         remoteRestChannel = null;
       } catch (final InterruptedException e) {//NOSONAR
         logger.error(e);
         // ignore
       }
     }
     futurePost.awaitOrInterruptible();
     final boolean result = futurePost.isSuccess();
     logger.info("End Post from {} to {} as {} with {}", start, stop, serverId,
                 result);
     return result;
   }
 
   public final boolean isKeepConnection() {
     return keepConnection;
   }
 
   public final void setStatus(final boolean ok) {
     if (ok) {
       futurePost.setSuccess();
     } else {
       futurePost.cancel();
     }
   }
 
   @Override
   public final void close() throws IOException {
     if (remoteRestChannel != null && !remoteRestChannel.isActive()) {
       remoteRestChannel.close();
       remoteRestChannel = null;
     }
   }
 }