/*
 *  Copyright (C) 2020 the original author or authors.
 *
 *  This program 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
 *  any later version.
 *
 *  This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package com.wehotel.config;

import io.netty.buffer.PooledByteBufAllocator;
import io.netty.buffer.UnpooledByteBufAllocator;
import io.netty.channel.AdaptiveRecvByteBufAllocator;
import io.netty.channel.ChannelOption;
import io.netty.channel.PreferHeapByteBufAllocator;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.timeout.ReadTimeoutHandler;
import io.netty.handler.timeout.WriteTimeoutHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.client.reactive.ReactorClientHttpConnector;
import org.springframework.http.client.reactive.ReactorResourceFactory;
import org.springframework.web.reactive.function.client.ExchangeStrategies;
import org.springframework.web.reactive.function.client.WebClient;
import reactor.netty.http.client.HttpClient;
import reactor.netty.resources.ConnectionProvider;
import reactor.netty.resources.LoopResources;

import java.time.Duration;
import java.util.concurrent.TimeUnit;

/**
 * @author lancer
 */
public abstract class WebClientConfig {

    protected static final Logger log = LoggerFactory.getLogger(WebClientConfig.class);

    private String        name;

    private int           maxConnections = 2_000;

    private Duration      maxIdleTime = Duration.ofMillis(40_000);

    private Duration      pendingAcquireTimeout = Duration.ofMillis(6_000);

    private long          connReadTimeout = 20_000;

    private long          connWriteTimeout = 20_000;

    private int           chConnTimeout = 20_000;

    private boolean       chTcpNodelay = true;

    private boolean       chSoKeepAlive = true;

    private boolean       compress = false;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = "wc-" + name;
    }

    public int getMaxConnections() {
        return maxConnections;
    }

    public void setMaxConnections(int maxConnections) {
        this.maxConnections = maxConnections;
    }

    public Duration getMaxIdleTime() {
        return maxIdleTime;
    }

    public void setMaxIdleTime(long maxIdleTime) {
        this.maxIdleTime = Duration.ofMillis(maxIdleTime);
    }

    public Duration getPendingAcquireTimeout() {
        return pendingAcquireTimeout;
    }

    public void setPendingAcquireTimeout(long pendingAcquireTimeout) {
        this.pendingAcquireTimeout = Duration.ofMillis(pendingAcquireTimeout);
    }

    public long getConnReadTimeout() {
        return connReadTimeout;
    }

    public void setConnReadTimeout(long connReadTimeout) {
        this.connReadTimeout = connReadTimeout;
    }

    public long getConnWriteTimeout() {
        return connWriteTimeout;
    }

    public void setConnWriteTimeout(long connWriteTimeout) {
        this.connWriteTimeout = connWriteTimeout;
    }

    public int getChConnTimeout() {
        return chConnTimeout;
    }

    public void setChConnTimeout(int chConnTimeout) {
        this.chConnTimeout = chConnTimeout;
    }

    public boolean isChTcpNodelay() {
        return chTcpNodelay;
    }

    public void setChTcpNodelay(boolean chTcpNodelay) {
        this.chTcpNodelay = chTcpNodelay;
    }

    public boolean isChSoKeepAlive() {
        return chSoKeepAlive;
    }

    public void setChSoKeepAlive(boolean chSoKeepAlive) {
        this.chSoKeepAlive = chSoKeepAlive;
    }

    public boolean isCompress() {
        return compress;
    }

    public void setCompress(boolean compress) {
        this.compress = compress;
    }

    private ConnectionProvider getConnectionProvider() {
        String cpName = name + "-cp";
        ConnectionProvider cp = ConnectionProvider.builder(cpName).maxConnections(maxConnections)
                .pendingAcquireTimeout(pendingAcquireTimeout).maxIdleTime(maxIdleTime).build();
        log.info(cpName + ' ' + cp);
        return cp;
    }

    private LoopResources getLoopResources() {
        String elPrefix = name + "-el";
        // LoopResources lr = LoopResources.create(elPrefix, 1, Runtime.getRuntime().availableProcessors(), true);
        LoopResources lr = LoopResources.create(elPrefix, Runtime.getRuntime().availableProcessors(), true);
        lr.onServer(false);
        log.info(name + "-lr " + lr);
        return lr;
    }

    protected ReactorResourceFactory reactorResourceFactory() {
        ReactorResourceFactory fact = new ReactorResourceFactory();
        fact.setUseGlobalResources(false);
        fact.setConnectionProvider(getConnectionProvider());
        fact.setLoopResources(getLoopResources());
        fact.afterPropertiesSet();
        return fact;
    }

    public WebClient webClient() {
        log.info(this.toString());
        // return WebClient.builder().exchangeStrategies(ExchangeStrategies.builder().codecs(configurer -> configurer.defaultCodecs().maxInMemorySize(-1)).build())
        //         .clientConnector(new ReactorClientHttpConnector(reactorResourceFactory(), httpClient -> {
        //             return httpClient.compress(compress).tcpConfiguration(tcpClient -> {
        //                 return tcpClient.doOnConnected(connection -> {
        //                     connection.addHandlerLast(new ReadTimeoutHandler(   connReadTimeout,   TimeUnit.MILLISECONDS))
        //                             .addHandlerLast(new WriteTimeoutHandler(  connWriteTimeout,  TimeUnit.MILLISECONDS));
        //                 }).option(ChannelOption.CONNECT_TIMEOUT_MILLIS, chConnTimeout)
        //                         .option(ChannelOption.TCP_NODELAY,            chTcpNodelay)
        //                         .option(ChannelOption.SO_KEEPALIVE,           chSoKeepAlive)
        //                         .option(ChannelOption.ALLOCATOR,              UnpooledByteBufAllocator.DEFAULT);
        //             });
        //         })).build();

        ConnectionProvider cp = getConnectionProvider();
        LoopResources lr = getLoopResources();
        HttpClient httpClient = HttpClient.create(cp).compress(compress).tcpConfiguration(
                tcpClient -> {
                    return tcpClient.runOn(lr, false)
                                    // .runOn(lr)
                                    // .bootstrap(
                                    //         bootstrap -> (
                                    //                 bootstrap.channel(NioSocketChannel.class)
                                    //         )
                                    // )
                                    .doOnConnected(
                                            connection -> {
                                                connection.addHandlerLast(new ReadTimeoutHandler( connReadTimeout,   TimeUnit.MILLISECONDS))
                                                          .addHandlerLast(new WriteTimeoutHandler(connWriteTimeout,  TimeUnit.MILLISECONDS));
                                            }
                                    )
                                    .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, chConnTimeout)
                                    .option(ChannelOption.TCP_NODELAY,            chTcpNodelay)
                                    .option(ChannelOption.SO_KEEPALIVE,           chSoKeepAlive)
                                    // .option(ChannelOption.ALLOCATOR,              PreferHeapByteBufAllocator.DEFAULT);
                                    // .option(ChannelOption.ALLOCATOR,              PooledByteBufAllocator.DEFAULT)
                                    .option(ChannelOption.ALLOCATOR,              UnpooledByteBufAllocator.DEFAULT);
                }
        );
        return WebClient.builder().exchangeStrategies(ExchangeStrategies.builder().codecs(configurer -> configurer.defaultCodecs().maxInMemorySize(-1)).build())
                                  .clientConnector(new ReactorClientHttpConnector(httpClient)).build();
    }

    @Override
    public String toString() {
        return " {name=" + name +
                ", maxConnections=" + maxConnections +
                ", maxIdleTime=" + maxIdleTime +
                ", pendingAcquireTimeout=" + pendingAcquireTimeout +
                ", connReadTimeout=" + connReadTimeout +
                ", connWriteTimeout=" + connWriteTimeout +
                ", chConnTimeout=" + chConnTimeout +
                ", chTcpNodelay=" + chTcpNodelay +
                ", chSoKeepAlive=" + chSoKeepAlive +
                ", compress=" + compress +
                '}';
    }
}