/*
    webchat, an HTML5/websocket chat platform
    Copyright (C) 2015  <email hidden>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License.

    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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/socket.h>
#include <gnutls/gnutls.h>
#include "../libwebsocket/websock.h"
#include "channels.h"
#include "db.h"
#include "users.h"

unsigned int usercount=0;
struct user** users=0;

gnutls_certificate_credentials_t cert=0;
gnutls_priority_t priority=0;

struct user* adduser(int socket, struct sockaddr* addr, socklen_t addrlen)
{
  ++usercount;
  users=realloc(users, sizeof(struct user*)*usercount);
  users[usercount-1]=malloc(sizeof(struct user));
#ifdef use_tls
  if(!cert)
  {
    gnutls_global_init();
    gnutls_certificate_allocate_credentials(&cert);
    gnutls_certificate_set_x509_key_file(cert, "cert.pem", "key.pem", GNUTLS_X509_FMT_PEM);
    gnutls_priority_init(&priority, "PERFORMANCE:%SERVER_PRECEDENCE", 0);
  }
  gnutls_init(&users[usercount-1]->socket, GNUTLS_SERVER);
  gnutls_priority_set(users[usercount-1]->socket, priority);
  gnutls_credentials_set(users[usercount-1]->socket, GNUTLS_CRD_CERTIFICATE, cert);
  gnutls_certificate_server_set_request(users[usercount-1]->socket, GNUTLS_CERT_IGNORE);
  gnutls_transport_set_int(users[usercount-1]->socket, socket);
  int ret;
  do{
    ret=gnutls_handshake(users[usercount-1]->socket);
  }
  while(ret<0 && !gnutls_error_is_fatal(ret));

  users[usercount-1]->rawsocket=socket;
#else
  users[usercount-1]->rawsocket=socket;
  users[usercount-1]->socket=&users[usercount-1]->rawsocket;
#endif
  users[usercount-1]->handshake=0;
  users[usercount-1]->channel=0;
  users[usercount-1]->bincmd=bincmd_none;
  users[usercount-1]->relations=0;
  users[usercount-1]->relationcount=0;
  users[usercount-1]->broadcasting=0;
  users[usercount-1]->firstmedia=0;
  users[usercount-1]->firstmedialength=0;
  users[usercount-1]->httpcam=0;
  users[usercount-1]->account=0;
  users[usercount-1]->modprivileges=0;
  users[usercount-1]->packet.data=0;
  unsigned int i=0;
  unsigned int j=0;
  while(j<usercount-1) // Find unique startnick
  {
    if(!strncmp(users[j]->nickname, "Guest-", 6) && atoi(&users[j]->nickname[6])==i){++i; j=0; continue;}
    ++j;
  }
// TODO: option to set nickname during handshake if it's not already taken, avoid guest joins
  users[usercount-1]->nickname=malloc(snprintf(0,0,"Guest-%u", i)+1);
  sprintf(users[usercount-1]->nickname, "Guest-%u", i);
  strcpy(users[usercount-1]->color, "000000");
  memcpy(&users[usercount-1]->sockaddr, addr, addrlen);
  return users[usercount-1];
}

void freeuser(struct user* user)
{
  unsigned int i;
  if(user->channel)
  {
    for(i=0; i<user->channel->usercount; ++i)
    {
      if(user->channel->users[i]==user)
      {
        --user->channel->usercount;
        memmove(&user->channel->users[i], &user->channel->users[i+1], sizeof(struct user*)*(user->channel->usercount-i));
        if(user->channel->usercount==0 && user->channel->id==-1) // Last one to leave frees the channel, unless it's a registered channel which might have a banlist and/or topic to keep
        {
          channel_free(user->channel);
        }
      }
    }
  }
  for(i=0; i<user->relationcount; ++i)
  {
    unsigned int j;
    for(j=0; j<user->relations[i].user->relationcount; ++j)
    {
      if(user->relations[i].user->relations[j].user==user)
      {
        --user->relations[i].user->relationcount;
        memmove(&user->relations[i].user->relations[j], &user->relations[i].user->relations[j+1], sizeof(struct relation)*(user->relations[i].user->relationcount-j));
        --j; // (moved everything one step down)
      }
    }
  }
  free(user->relations);
  free(user->nickname);
#ifdef use_tls
  gnutls_deinit(user->socket);
#endif
  close(user->rawsocket);
  free(user->account);
  free(user->packet.data);
  free(user);
}

void user_addrelation(struct user* a, struct user* b, enum relationtype type)
{
  ++a->relationcount;
  a->relations=realloc(a->relations, sizeof(struct relation)*a->relationcount);
  a->relations[a->relationcount-1].user=b;
  a->relations[a->relationcount-1].type=type;
  type=(type%2?type-1:type+1); // Opposite type
  ++b->relationcount;
  b->relations=realloc(b->relations, sizeof(struct relation)*b->relationcount);
  b->relations[b->relationcount-1].user=a;
  b->relations[b->relationcount-1].type=type;
}

void user_removerelation(struct user* a, struct user* b, enum relationtype type)
{
  unsigned int i;
  for(i=0; i<a->relationcount; ++i)
  {
    if(a->relations[i].user==b && a->relations[i].type==type)
    {
      --a->relationcount;
      memmove(&a->relations[i], &a->relations[i+1], sizeof(struct relation)*(a->relationcount-i));
      --i;
    }
  }
  type=(type%2?type-1:type+1); // Opposite type
  for(i=0; i<b->relationcount; ++i)
  {
    if(b->relations[i].user==a && b->relations[i].type==type)
    {
      --b->relationcount;
      memmove(&b->relations[i], &b->relations[i+1], sizeof(struct relation)*(b->relationcount-i));
      --i;
    }
  }
}

void user_removerelations(struct user* user, enum relationtype type)
{
  unsigned int i;
  for(i=0; i<user->relationcount; ++i)
  {
    if(user->relations[i].type==type)
    {
      user_removerelation(user, user->relations[i].user, type);
      --i;
    }
  }
}

char user_login(struct user* user, const char* username, const char* password)
{
  char* passhash;
  char* salt;
  int userid;
  if(!db_finduser(username, &userid, &passhash, &salt)){return 0;}
  // Hash the given password+salt
  char hash[129];
  db_mkhash(password, salt, hash);
  if(!strcmp(hash, passhash))
  {
    free(passhash);
    free(salt);
    // Mark user as logged in, check for mod privileges
    free(user->account); // Avoid unlikely but potential memory leak (logging in again without logging out)
    user->account=strdup(username);
    if(user->channel->id>-1)
    {
      user->modprivileges=db_getmod(user->channel->id, userid);
    }else{
      user->modprivileges=0;
    }
    return 1;
  }
  free(passhash);
  free(salt);
  return 0;
}

void user_sendmodmsg(struct user* user)
{
  char modmsg[snprintf(0,0, "mod:%s:%i", user->nickname, user->modprivileges)+1];
  sprintf(modmsg, "mod:%s:%i", user->nickname, user->modprivileges);
  channel_write(user->channel, modmsg, strlen(modmsg), WEBSOCK_TEXT, 0);
}