#include "socket.h"
#include "stringf.h"
#include <netdb.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>

int socket_bind(string host_port_str) {
  const char *cs(strrchr(host_port_str.c_str(),':'));
  const string node(!cs?"":host_port_str.substr(0,cs-host_port_str.c_str()));
  const string service(!cs?host_port_str:cs+1);
  struct addrinfo hints={}; // designated initializer: error: missing initializer for member ... [-Werror=missing-field-initializers]
  hints.ai_family=AF_UNSPEC;    /* Allow IPv4 or IPv6 */
  hints.ai_socktype=SOCK_STREAM;
  hints.ai_flags=AI_PASSIVE|AI_ADDRCONFIG;    /* For wildcard IP address */
  struct addrinfo *result;
  int err(getaddrinfo(node.empty()?NULL:node.c_str(),service.c_str(),&hints,&result));
  if (err)
    fatal("<%s>:<%s>: %s",node.c_str(),service.c_str(),gai_strerror(err));
  int fd=-1;
  struct addrinfo *rp;
  for (rp=result;rp;rp=rp->ai_next) {
    fd=socket(rp->ai_family,rp->ai_socktype,rp->ai_protocol);
    if (fd==-1)
      continue;
    static const int int1(1);
    err=setsockopt(fd,SOL_SOCKET,SO_REUSEADDR,&int1,sizeof(int1));
    assert(!err);
    if (bind(fd,rp->ai_addr,rp->ai_addrlen)==0)
      break;
    err=close(fd);
    assert(!err);
  }
  if (rp==NULL)
    fatal("Cannot bind(): <%s>:<%s>: %m",node.c_str(),service.c_str());
  assert(fd!=-1);
  freeaddrinfo(result);
  err=listen(fd,SOMAXCONN);
  assert(!err);
  return fd;
}

string sockaddr_string(const struct sockaddr *sockaddrp,socklen_t socklen) {
  char hostname[NI_MAXHOST];
  char servname[NI_MAXSERV];
  const int err=getnameinfo(sockaddrp,socklen,hostname,sizeof(hostname),servname,sizeof(servname),NI_NUMERICSERV/*flags*/);
  assert(!err);
  return stringf("%s:%s",hostname,servname);
}

string socket_name(int socket_fd) {
  struct sockaddr sockaddr;
  socklen_t socklen(sizeof(sockaddr));
  const int err(getsockname(socket_fd,&sockaddr,&socklen));
  assert(!err);
  return sockaddr_string(&sockaddr,socklen);
}

static void socket_setopt(int fd) {
  static const int int1(1);
  int err;
  err=setsockopt(fd,SOL_SOCKET,SO_KEEPALIVE,&int1,sizeof(int1));
  assert(!err);
  static const uint8_t tos(IPTOS_LOWDELAY);
  err=setsockopt(fd,IPPROTO_IP,IP_TOS,&tos,sizeof(tos));
  assert(!err);
  err=setsockopt(fd,IPPROTO_IP,TCP_NODELAY,&int1,sizeof(int1));
  assert(!err);
}

int socket_accept(int listen_fd,function<void(int client_fd,string addr)> msgfunc) {
  struct sockaddr sockaddr;
  socklen_t socklen(sizeof(sockaddr));
  const int client_fd(accept(listen_fd,&sockaddr,&socklen));
  assert(client_fd>=0);
  msgfunc(client_fd,sockaddr_string(&sockaddr,socklen));
  socket_setopt(client_fd);
  return client_fd;
}

int socket_connect(const string &host_port_str,unsigned retries) {
  const char *cs(strrchr(host_port_str.c_str(),':'));
  if (!cs)
    fatal("Error parsing <host>:<port>: %s",host_port_str.c_str());
  const string node(host_port_str.substr(0,cs-host_port_str.c_str()));
  const string service(cs+1);
  struct addrinfo hints={}; // designated initializer: error: missing initializer for member ... [-Werror=missing-field-initializers]
  hints.ai_family=AF_UNSPEC;    /* Allow IPv4 or IPv6 */
  hints.ai_socktype=SOCK_STREAM;
  struct addrinfo *result;
  int err=getaddrinfo(node.c_str(),service.c_str(),&hints,&result);
  if (err)
    fatal("Error parsing node+service: <%s>:<%s>: %s",node.c_str(),service.c_str(),gai_strerror(err));
  int fd;
  struct addrinfo *rp;
  for (unsigned retryno=0;retryno<1+retries;++retryno) {
    if (retryno) {
      warning("Sleeping 1 second for connect retry #%u/%u",retryno,retries);
      err=sleep(1);
      assert(!err);
    }
    for (rp=result;rp;rp=rp->ai_next) {
      fd=socket(rp->ai_family,rp->ai_socktype,rp->ai_protocol);
      if (fd==-1)
	continue;
      if (connect(fd,rp->ai_addr,rp->ai_addrlen)==0)
	break;
      err=close(fd);
      assert(!err);
    }
    if (rp==NULL)
      warning("Could not connect(): <%s>:<%s>: %m",node.c_str(),service.c_str());
    else
      break;
  }
  freeaddrinfo(result);
  if (rp==NULL)
    fatal("Could not connect(), giving up");
  socket_setopt(fd);
  return fd;
}