/*
 * network.cpp
 *
 *  Created on: 2022年3月4日
 *      Author: pengzc
 */

#include "network.h"

#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <poll.h>
#include <sys/socket.h>
#include <netdb.h>
#include <arpa/inet.h>

#include "utils/Log.h"

namespace base {

/**
 * 设置非阻塞模式
 */
static int SetNonBlock(int fd) {
  int flags = fcntl(fd, F_GETFL, 0);
  if (flags < 0) {
    LOGE("Get flags error:%s", strerror(errno));
    return -1;
  }
  flags |= O_NONBLOCK;
  if (fcntl(fd, F_SETFL, flags) < 0) {
    LOGE("Set flags error:%s", strerror(errno));
    return -1;
  }
  return 0;
}

/**
 * -1 error
 * 0 timeout
 * >0 get event
 */
static int Poll(int fd, int events, int timeout_millis, int* revents) {
  int ret = -1;
  struct pollfd pfd;
  memset(&pfd, 0, int(sizeof(pfd)));
  pfd.fd = fd;
  pfd.events = events;
  // retry again for EINTR
  for (int i = 0; i < 2; i++) {
    ret = ::poll(&pfd, 1, timeout_millis);
    if (-1 == ret && EINTR == errno)
      continue;
    break;
  }
  if (ret >= 0) {
    *revents = pfd.revents;
  }
  return ret;
}

static int NonBlockConnect(int fd, const struct sockaddr* ai_addr,
    socklen_t ai_addrlen, int timeout_millis) {
  /*设置套接字为非阻塞*/
  if (SetNonBlock(fd) != 0) {
    return SOCKET_ERROR;
  }
  /*阻塞情况下linux系统默认超时时间为75s*/
  int ret = ::connect(fd, ai_addr, ai_addrlen);
  if (ret == 0) {
    return ret;
  }
  if (errno != EINPROGRESS) {
    LOGE("connect failure, %s(%d)", strerror(errno), errno);
    return SOCKET_ERROR;
  }
  //LOGD("Doing connection.\n");
  /*正在处理连接*/
  int revents = 0;
  ret = Poll(fd, POLLIN | POLLOUT | POLLHUP | POLLERR | POLLNVAL,
      timeout_millis, &revents);
  if (ret < 0) {
    LOGE("poll failure, %s(%d)", strerror(errno), errno);
    return SOCKET_ERROR;
  }
  if (ret == 0) {
    return SOCKET_TIMEOUT;
  }

  if (((revents & POLLOUT) != 0) && ((revents & POLLIN) == 0)) {
    return SOCKET_SUCCESS;
  }
  if ((revents & POLLOUT) != 0 && (revents & POLLIN) != 0) {
    int err = 0;
    int errlen = sizeof(err);
    if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, (socklen_t*)&errlen)
        == -1) {
      LOGE("getsockopt failure, %s", strerror(errno));
      return SOCKET_ERROR;
    }
    if (err) {
      errno = err;
      LOGE("connect failure, %s(%d)", strerror(errno), errno);
      return SOCKET_ERROR;
    }
  }
  return SOCKET_ERROR;
}

static int Send(int sock_fd, const uint8_t* buffer, size_t buflen) {
  if (buflen <= 0) {
    return 0;
  }
  if (buffer == NULL) {
    return 0;
  }
  size_t tmp;
  size_t total = buflen;
  const unsigned char *p = buffer;
  while (true) {
    tmp = send(sock_fd, p, total, 0);
    if (tmp < 0) {
      // 当send收到信号时,可以继续写,但这里返回-1.
      if (errno == EINTR) {
        usleep(1000 * 100);
        continue;
      }
      // 当socket是非阻塞时,如返回此错误,表示写缓冲队列已满,
      // 在这里做延时后再重试.
      if (errno == EAGAIN) {
        usleep(1000 * 100);
        continue;
      }
      return -1;
    }

    if ((size_t) tmp == total) {
//        LOGD("send success");
      return buflen;
    }

    total -= tmp;
    p += tmp;
  }
  return tmp;
}

Socket::Socket() {
  socket_ = -1;
}

Socket::~Socket() {
}

int Socket::Connect(const std::string& host, int port, int timeout_millis) {
  if (socket_ >= 0) {
    LOGE("already connect");
    return SOCKET_ERROR;
  }
  struct addrinfo host_info;
  struct addrinfo * host_info_list = NULL;
  memset(&host_info, 0, int(sizeof(host_info)));
  host_info.ai_family = AF_UNSPEC;
  host_info.ai_socktype = SOCK_STREAM;

  char port_str[32] = {0};
  snprintf(port_str, int(sizeof(port_str)), "%d", port);
  int ret = getaddrinfo(host.c_str(), port_str, &host_info,
      &host_info_list);
  if (ret != 0) {
    LOGE("host could not be resolved");
    return SOCKET_GET_ADDRESS_INFO;
  }
  int sock = socket(host_info_list->ai_family, host_info_list->ai_socktype,
      host_info_list->ai_protocol);
  if (sock == -1) {
    LOGE("could not open socket, %s(%d)", strerror(errno), errno);
    freeaddrinfo(host_info_list);
    return SOCKET_INVALID;
  }

  ret = NonBlockConnect(sock, host_info_list->ai_addr,
      host_info_list->ai_addrlen, timeout_millis);

  if (ret != 0) {
    freeaddrinfo(host_info_list);
    close(sock);
    return ret;
  }
  socket_ = sock;
  freeaddrinfo(host_info_list);
  return 0;
}

int Socket::Write(uint8_t* data, int data_len) {
  if (socket_ < 0) {
    return SOCKET_INVALID;
  }
  return Send(socket_, data, data_len);
}

int Socket::Read(uint8_t* buffer, int buffer_len, int timeout_millis) {
  if (socket_ < 0) {
    //没有连接
    return SOCKET_INVALID;
  }

  int revents = 0;
  int ret = Poll(socket_, POLLIN | POLLHUP | POLLERR | POLLNVAL, timeout_millis, &revents);
  if (ret < 0) {
    return SOCKET_ERROR;
  }
  if (ret == 0) {
    return SOCKET_TIMEOUT;
  }
  int recv_bytes = recv(socket_, buffer, buffer_len, 0);
  if (recv_bytes == 0) {
    //连接已关闭
    //LOGD("recv 0, close it");
    Close();
    return 0;
  } else if (recv_bytes < 0) {
    //添加错误处理
    if ((errno == EINTR) || (errno == EWOULDBLOCK) || (errno == EAGAIN)) {
      //继续recv
      return SOCKET_TIMEOUT;
    } else {
      LOGE("recv: %s(%d)", strerror(errno), errno);
      Close();
      return SOCKET_ERROR;
    }
  }
  return recv_bytes;
}

int Socket::Close() {
  if (socket_ >= 0) {
    close(socket_);
    socket_ = -1;
  }
  return 0;
}

InetAddress Socket::inet_address() const {
  return address_;
}

//ServerSocket

ServerSocket::ServerSocket(int port) {
  server_socket_ = socket(PF_INET, SOCK_STREAM, 0);
  if (server_socket_ < 0) {
    LOGE("socket failure, %s(%d)", strerror(errno), errno);
    return;
  }

  int on = 1;
  if (setsockopt(server_socket_, SOL_SOCKET, SO_REUSEADDR, &on,
      socklen_t(sizeof(on))) != 0) {
     LOGE("setsockopt failure, %s(%d)", strerror(errno), errno);
     goto failure;
  }
  memset(&server_addr_, 0, int(sizeof(server_addr_)));
  server_addr_.sin_family = AF_INET;
  server_addr_.sin_port = htons(port);
  server_addr_.sin_addr.s_addr = htonl(INADDR_ANY);
  if (bind(server_socket_, (struct sockaddr*) &server_addr_,
      socklen_t(sizeof(server_addr_))) < 0) {
    LOGE("bind failure, %s(%d)", strerror(errno), errno);
    goto failure;
  }
  if (listen(server_socket_, 64) < 0) {
    LOGE("listen failure, %s(%d)", strerror(errno), errno);
    goto failure;
  }
  return;
failure:
  if (server_socket_ >= 0) {
    close(server_socket_);
    server_socket_ = -1;
  }
}

ServerSocket::~ServerSocket() {
  if (server_socket_ >= 0) {
    close(server_socket_);
    server_socket_ = -1;
  }
}

int ServerSocket::Accept(Socket* socket) {
  if (server_socket_ < 0) {
    return SOCKET_INVALID;
  }
  if (socket == NULL) {
    LOGE("argument socket must be not null");
    return SOCKET_INVALID;
  }
  socklen_t addr_len = socklen_t(sizeof(socket->address_.address_));
  int client = accept(server_socket_,
      (struct sockaddr*) &socket->address_.address_, &addr_len);
  if (client < 0) {
    LOGD("accept failure, %s(%d)", strerror(errno), errno);
    return SOCKET_ERROR;
  }
  socket->socket_ = client;
  return client;
}

InetAddress::InetAddress() {
  memset(&address_, 0, int(sizeof(address_)));
}

InetAddress::InetAddress(const std::string& host, int port) {
  memset(&address_, 0, int(sizeof(address_)));
  address_.sin_family = AF_INET;
  address_.sin_port = htons(port);
  address_.sin_addr.s_addr = inet_addr(host.c_str());
}

std::string InetAddress::ipv4() const {
  struct sockaddr_in in = {0};
  if (0 == memcmp(&address_, &in, int(sizeof(in)))) {
    //未初始化的地址返回空
    return "";
  }
  return inet_ntoa(address_.sin_addr);
}

DatagramSocket::DatagramSocket() {
  socket_ = socket(AF_INET, SOCK_DGRAM, 0);
  if (socket_ < 0) {
    LOGE("socket failure, %s(%d)", strerror(errno), errno);
  }
}

DatagramSocket::DatagramSocket(int port) {
  socket_ = socket(AF_INET, SOCK_DGRAM, 0);
  if (socket_ < 0) {
    LOGE("socket failure, %s(%d)", strerror(errno), errno);
    return;
  }
  struct sockaddr_in ser_addr;
  memset(&ser_addr, 0, int(sizeof(ser_addr)));
  ser_addr.sin_family = AF_INET;
  ser_addr.sin_addr.s_addr = htonl(INADDR_ANY);
  ser_addr.sin_port = htons(port);
  int ret = bind(socket_, (struct sockaddr*) &ser_addr,
      socklen_t(sizeof(ser_addr)));
  if (ret < 0) {
    LOGE("bind failure, %s(%d)", strerror(errno), errno);
    close(socket_);
    socket_ = -1;
  }
}

DatagramSocket::~DatagramSocket() {
}

int DatagramSocket::SendTo(const InetAddress& address, const uint8_t* data,
    int len) {
  if (socket_ < 0) {
    return SOCKET_INVALID;
  }
  return sendto(socket_, data, len, 0, (sockaddr*) &address.address_,
      socklen_t(sizeof(address.address_)));
}

int DatagramSocket::Receive(InetAddress* address, uint8_t* buffer,
    int buffer_length, int timeout_millis) {
  if (socket_ < 0) {
    return SOCKET_INVALID;
  }
  int revents = 0;
  int ret = Poll(socket_, POLLIN, timeout_millis, &revents);
  if (ret < 0) {
    return SOCKET_ERROR;
  }
  if (ret == 0) {
    return SOCKET_TIMEOUT;
  }
  sockaddr* addr = NULL;
  socklen_t addr_len = 0;
  if (address != NULL) {
    addr = (sockaddr*) &address->address_;
    addr_len = sizeof(address->address_);
  }
  ret = recvfrom(socket_, buffer, buffer_length, 0, addr, &addr_len);
  if (ret == 0) {
    //连接已关闭
    Close();
    return 0;
  } else if (ret < 0) {
    if ((errno == EINTR) || (errno == EWOULDBLOCK) || (errno == EAGAIN)) {
      //继续recv
      return SOCKET_TIMEOUT;
    } else {
      LOGE("recv: %s(%d)", strerror(errno), errno);
      Close();
      return SOCKET_ERROR;
    }
  }
  return ret;
}

int DatagramSocket::Close() {
  if (socket_ >= 0) {
    close(socket_);
    socket_ = -1;
  }
  return 0;
}


#if 0  //测试程序段
  std::thread server_thread([](){
    net::ServerSocket server(8080);
    while(true) {
      net::Socket so;
      LOGE("服务端 等待连接");
      int ret = server.Accept(&so);
      if (ret < 0) {
        LOGE("Accept failure %d", ret);
        break;
      }
      const char* msg = "hello";
      uint8_t buf[1024] = {0};
      ret = so.Read(buf, int(sizeof(buf)), 2000);
      LOGE("服务端 读取 %d %s", ret, buf);

      ret = so.Write((uint8_t*)msg, strlen(msg));
      LOGE("服务端 发送 %d %s", ret, ret == strlen(msg) ? "成功" : "失败");
      so.Close();
    }
  });
  server_thread.detach();

  int test_count = 100000;
  usleep(1000 * 1000);
  while(test_count--) {
    LOGD("test count %d", test_count);
    net::Socket so;
    //net::Conn* conn = net::Dial("tcp", "14.215.177.38:80");
//    int ret = so.Connect("14.215.177.38", 80, 3000);
    int ret = so.Connect("127.0.0.1", 8080, 3000);
//    int ret = so.Connect("www.baidu.com", 80, 3000);
    LOGD("连接 %d", ret);
    if (ret == 0)
    {
      uint8_t buf[2048] = {0};
      const char* req = "GET / HTTP/1.1\r\nConnection: close\r\n\r\n";
      //发送
      ret = so.Write((uint8_t*)req, strlen(req));
      LOGD("客户端 写 %d", ret);
      while (true) {
        //读取，超时1000毫秒
        int n = so.Read(buf, int(sizeof(buf)) - 1, 1000);
        if (n > 0) {
          buf[n] = 0;
          LOGD("客户端 读取 %d字节： %s", n, buf);
        } else if (n == 0) {
          LOGD("客户端 连接正常断开");
          break;
        } else {
          if (n == net::SOCKET_TIMEOUT) {
            LOGD("客户端 读取超时, 继续读");
            continue;
          } else {
            LOGE("客户端 出错 %d", n);
            break;
          }
        }
      }
      //关闭连接
      so.Close();
      //释放内存
    }
  }
#endif

//测试UDP
#if 0
  {
    std::thread server_thread([](){
      net::DatagramSocket server(8080);
      while(true) {
        LOGE("服务端 等待接收");
        net::InetAddress from_address;
        uint8_t buffer[1024] = {0};
        int ret = server.Receive(&from_address, buffer, int(sizeof(buffer)), 2000);

        if (ret == net::SOCKET_TIMEOUT) {
          LOGD("服务端接收超时");
          continue;
        }
        if (ret < 0) {
          LOGE("服务端接收出错 %d", ret);
          break;
        }
        LOGE("服务端 读取 来自 %s %d %s", from_address.ipv4().c_str(), ret, buffer);

        const char* msg = "hello";
        ret = server.SendTo(from_address, (uint8_t*)msg, int(strlen(msg)));
        LOGE("服务端 发送 %d %s", ret, ret == strlen(msg) ? "成功" : "失败");
      }
    });
    server_thread.detach();
  }
  usleep(1000 * 1000);
  {
    //UDP客户端
    net::InetAddress address("127.0.0.1", 8080);
    net::DatagramSocket so;
    while (true) {
      const char* msg = "I am from client";
      int ret = so.SendTo(address, (uint8_t*)msg, int(strlen(msg)));
      LOGE("客户端 发送 %d %s", ret, ret == strlen(msg) ? "成功" : "失败");

      uint8_t buffer[128] = {0};
      ret = so.Receive(&address, buffer, int(sizeof(buffer)), 2000);
      if (ret == net::SOCKET_TIMEOUT) {
        LOGE("客户端 接收超时");
        continue;
      }
      if (ret < 0) {
        LOGE("客户端 接收失败");
        break;
      }
      LOGE("客户端 接收 来自 %s %d  %s", address.ipv4().c_str(), ret, buffer);
    }
  }

#endif


} /* namespace base */