/*
    This file is part of telegram-cli.

    Telegram-cli 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 2 of the License, or
    (at your option) any later version.

    Telegram-cli 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 telegram-cli.  If not, see <http://www.gnu.org/licenses/>.

    Copyright Vitaly Valtman 2013-2014
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#define _GNU_SOURCE
#define READLINE_CALLBACKS

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef READLINE_GNU
#include <readline/readline.h>
#include <readline/history.h>
#else
#include <readline/readline.h>
#include <readline/history.h>
#endif

#include <errno.h>
#include <poll.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <event2/event.h>

#include "interface.h"
#include "telegram.h"
#include "loop.h"
#include "lua-tg.h"
#include "tgl.h"
#include "binlog.h"

int verbosity;
extern int readline_disabled;

int binlog_read;
extern char *default_username;
extern char *auth_token;
void set_default_username (const char *s);
extern int binlog_enabled;

extern int unknown_user_list_pos;
extern int unknown_user_list[];
int register_mode;
extern int safe_quit;
extern int sync_from_start;

void got_it (char *line, int len);
void write_state_file (void);

static char *line_buffer;
static int line_buffer_size;
static int line_buffer_pos;
static int delete_stdin_event;

static void stdin_read_callback_all (int arg, short what, struct event *self) {
  if (!readline_disabled) {
    if (((long)arg) & 1) {
      rl_callback_read_char ();
    } else {
      char *line = 0;        
      size_t len = 0;
      assert (getline (&line, &len, stdin) >= 0);
      got_it (line, strlen (line));
    }
  } else {
    while (1) {
      if (line_buffer_pos == line_buffer_size) {
        line_buffer = realloc (line_buffer, line_buffer_size * 2 + 100);
        line_buffer_size = line_buffer_size * 2 + 100;
        assert (line_buffer);
      }
      int r = read (0, line_buffer + line_buffer_pos, line_buffer_size - line_buffer_pos);
      //logprintf ("r = %d, size = %d, pos = %d, what = 0x%x, fd = %d\n", r, line_buffer_size, line_buffer_pos, (int)what, fd);
      if (r < 0) {
        perror ("read");
        break;
      }
      if (r == 0) {
        //struct event *ev = event_base_get_running_event (tgl_state.ev_base);
        //event_del (ev);
        //event_del (self);
        
        delete_stdin_event = 1;
        break;
      }
      line_buffer_pos += r;

      while (1) {
        int p = 0;
        while (p < line_buffer_pos && line_buffer[p] != '\n') { p ++; }
        if (p < line_buffer_pos) {
          if (((long)arg) & 1) {
            line_buffer[p] = 0;
            interpreter (line_buffer);
          } else {
            got_it (line_buffer, p + 1);
          }
          memmove (line_buffer, line_buffer + p + 1, line_buffer_pos - p - 1);
          line_buffer_pos -= (p + 1);
        } else {
          break;
        }
      }
    }
  }
}

static void stdin_read_callback_char (evutil_socket_t fd, short what, void *arg) {
  stdin_read_callback_all (1, what, arg);
}

static void stdin_read_callback_line (evutil_socket_t fd, short what, void *arg) {
  stdin_read_callback_all (2, what, arg);
}

void net_loop (int flags, int (*is_end)(void)) {
  delete_stdin_event = 0;
  if (verbosity >= E_DEBUG) {
    logprintf ("Starting netloop\n");
  }
  struct event *ev = 0;
  if (flags & 3) {
    if (flags & 1) {
      ev = event_new (tgl_state.ev_base, 0, EV_READ | EV_PERSIST, stdin_read_callback_char, 0);
    } else {
      ev = event_new (tgl_state.ev_base, 0, EV_READ | EV_PERSIST, stdin_read_callback_line, 0);
    }
    event_add (ev, 0);
  }
  while (!is_end || !is_end ()) {

    event_base_loop (tgl_state.ev_base, EVLOOP_ONCE);

    if (ev && delete_stdin_event) {
      event_free (ev);
      ev = 0;
    }

    #ifdef USE_LUA
      lua_do_all ();
    #endif
    if (safe_quit && !tgl_state.active_queries) {
      printf ("All done. Exit\n");
      if (!readline_disabled) {
        rl_callback_handler_remove ();
      }
      exit (0);
    }
    write_state_file ();
    update_prompt ();
    if (unknown_user_list_pos) {
      int i;
      for (i = 0; i < unknown_user_list_pos; i++) {
        tgl_do_get_user_info (TGL_MK_USER (unknown_user_list[i]), 0, 0, 0);
      }
      unknown_user_list_pos = 0;
    }   
  }

  if (ev) {
    event_free (ev);
  }
  
  if (verbosity >= E_DEBUG) {
    logprintf ("End of netloop\n");
  }
}

char **_s;
size_t *_l;
int got_it_ok;

void got_it (char *line, int len) {
  assert (len > 0);
  line[-- len] = 0; // delete end of line
  *_s = line;
  *_l = len;  
  got_it_ok = 1;
}

int is_got_it (void) {
  return got_it_ok;
}

int net_getline (char **s, size_t *l) {
  fflush (stdout);
//  rl_already_prompted = 1;
  got_it_ok = 0;
  _s = s;
  _l = l;
//  rl_callback_handler_install (0, got_it);
  net_loop (2, is_got_it);
  return 0;
}

int main_loop (void) {
  net_loop (1, 0);
  return 0;
}

struct tgl_dc *cur_a_dc;
int is_authorized (void) {
  return tgl_authorized_dc (cur_a_dc);
}

int all_authorized (void) {
  int i;
  for (i = 0; i <= tgl_state.max_dc_num; i++) if (tgl_state.DC_list[i]) {
    if (!tgl_authorized_dc (tgl_state.DC_list[i])) {
      return 0;
    }
  }
  return 1;
}

int config_got;

int got_config (void) {
  return config_got;
}

void on_get_config (void *extra, int success) {
  if (!success) {
    logprintf ("Can not get config.\n");
    exit (1);
  }
  config_got = 1;

}

int should_register;
char *hash;
void sign_in_callback (void *extra, int success, int registered, const char *mhash) {
  if (!success) {
    logprintf ("Can not send code\n");
    exit (1);
  }
  should_register = !registered;
  hash = strdup (mhash);
}


int signed_in_ok;

void sign_in_result (void *extra, int success, struct tgl_user *U) {
  if (!success) {
    logprintf ("Can not login\n");
    exit (1);
  }
  signed_in_ok = 1;
}

int signed_in (void) {
  return signed_in_ok;
}

int sent_code (void) {
  return hash != 0;
}

int dc_signed_in (void) {
  return tgl_signed_dc (cur_a_dc);
}

void export_auth_callback (void *DC, int success) {
  if (!success) {
    logprintf ("Can not export auth\n");
    exit (1);
  }
}

int d_got_ok;
void get_difference_callback (void *extra, int success) {
  assert (success);
  d_got_ok = 1;
}

int dgot (void) {
  return d_got_ok;
}

int zero[512];


int readline_active;
int new_dc_num;
int wait_dialog_list;

extern struct tgl_update_callback upd_cb;

#define DC_SERIALIZED_MAGIC 0x868aa81d
#define STATE_FILE_MAGIC 0x28949a93
#define SECRET_CHAT_FILE_MAGIC 0x37a1988a

char *get_auth_key_filename (void);
char *get_state_filename (void);
char *get_secret_chat_filename (void);

void read_state_file (void) {
  if (binlog_enabled) { return; }
  int state_file_fd = open (get_state_filename (), O_CREAT | O_RDWR, 0600);
  if (state_file_fd < 0) {
    return;
  }
  int version, magic;
  if (read (state_file_fd, &magic, 4) < 4) { close (state_file_fd); return; }
  if (magic != (int)STATE_FILE_MAGIC) { close (state_file_fd); return; }
  if (read (state_file_fd, &version, 4) < 4) { close (state_file_fd); return; }
  assert (version >= 0);
  int x[4];
  if (read (state_file_fd, x, 16) < 16) {
    close (state_file_fd); 
    return;
  }
  int pts = x[0];
  int qts = x[1];
  int seq = x[2];
  int date = x[3];
  close (state_file_fd); 
  bl_do_set_seq (seq);
  bl_do_set_pts (pts);
  bl_do_set_qts (qts);
  bl_do_set_date (date);
}


void write_state_file (void) {
  if (binlog_enabled) { return; }
  static int wseq;
  static int wpts;
  static int wqts;
  static int wdate;
  if (wseq >= tgl_state.seq && wpts >= tgl_state.pts && wqts >= tgl_state.qts && wdate >= tgl_state.date) { return; }
  wseq = tgl_state.seq; wpts = tgl_state.pts; wqts = tgl_state.qts; wdate = tgl_state.date;
  int state_file_fd = open (get_state_filename (), O_CREAT | O_RDWR, 0600);
  if (state_file_fd < 0) {
    logprintf ("Can not write state file '%s': %m\n", get_state_filename ());
    exit (2);
  }
  int x[6];
  x[0] = STATE_FILE_MAGIC;
  x[1] = 0;
  x[2] = wpts;
  x[3] = wqts;
  x[4] = wseq;
  x[5] = wdate;
  assert (write (state_file_fd, x, 24) == 24);
  close (state_file_fd); 
}

void write_dc (struct tgl_dc *DC, void *extra) {
  int auth_file_fd = *(int *)extra;
  if (!DC) { 
    int x = 0;
    assert (write (auth_file_fd, &x, 4) == 4);
    return;
  } else {
    int x = 1;
    assert (write (auth_file_fd, &x, 4) == 4);
  }

  assert (DC->has_auth);

  assert (write (auth_file_fd, &DC->port, 4) == 4);
  int l = strlen (DC->ip);
  assert (write (auth_file_fd, &l, 4) == 4);
  assert (write (auth_file_fd, DC->ip, l) == l);
  assert (write (auth_file_fd, &DC->auth_key_id, 8) == 8);
  assert (write (auth_file_fd, DC->auth_key, 256) == 256);
}

void write_auth_file (void) {
  if (binlog_enabled) { return; }
  int auth_file_fd = open (get_auth_key_filename (), O_CREAT | O_RDWR, 0600);
  assert (auth_file_fd >= 0);
  int x = DC_SERIALIZED_MAGIC;
  assert (write (auth_file_fd, &x, 4) == 4);
  assert (write (auth_file_fd, &tgl_state.max_dc_num, 4) == 4);
  assert (write (auth_file_fd, &tgl_state.dc_working_num, 4) == 4);

  tgl_dc_iterator_ex (write_dc, &auth_file_fd);

  assert (write (auth_file_fd, &tgl_state.our_id, 4) == 4);
  close (auth_file_fd);
}

void write_secret_chat (tgl_peer_t *_P, void *extra) {
  struct tgl_secret_chat *P = (void *)_P;
  if (tgl_get_peer_type (P->id) != TGL_PEER_ENCR_CHAT) { return; }
  if (P->state != sc_ok) { return; }
  int *a = extra;
  int fd = a[0];
  a[1] ++;

  int id = tgl_get_peer_id (P->id);
  assert (write (fd, &id, 4) == 4);
  //assert (write (fd, &P->flags, 4) == 4);
  int l = strlen (P->print_name);
  assert (write (fd, &l, 4) == 4);
  assert (write (fd, P->print_name, l) == l);
  assert (write (fd, &P->user_id, 4) == 4);
  assert (write (fd, &P->admin_id, 4) == 4);
  assert (write (fd, &P->date, 4) == 4);
  assert (write (fd, &P->ttl, 4) == 4);
  assert (write (fd, &P->layer, 4) == 4);
  assert (write (fd, &P->access_hash, 8) == 8);
  assert (write (fd, &P->state, 4) == 4);
  assert (write (fd, &P->key_fingerprint, 8) == 8);
  assert (write (fd, &P->key, 256) == 256);
}

void write_secret_chat_file (void) {
  if (binlog_enabled) { return; }
  int secret_chat_fd = open (get_secret_chat_filename (), O_CREAT | O_RDWR, 0600);
  assert (secret_chat_fd >= 0);
  int x = SECRET_CHAT_FILE_MAGIC;
  assert (write (secret_chat_fd, &x, 4) == 4);
  x = 0; 
  assert (write (secret_chat_fd, &x, 4) == 4); // version
  assert (write (secret_chat_fd, &x, 4) == 4); // num

  int y[2];
  y[0] = secret_chat_fd;
  y[1] = 0;

  tgl_peer_iterator_ex (write_secret_chat, y);

  lseek (secret_chat_fd, 8, SEEK_SET);
  assert (write (secret_chat_fd, &y[1], 4) == 4);
  close (secret_chat_fd);
}

void read_dc (int auth_file_fd, int id, unsigned ver) {
  int port = 0;
  assert (read (auth_file_fd, &port, 4) == 4);
  int l = 0;
  assert (read (auth_file_fd, &l, 4) == 4);
  assert (l >= 0 && l < 100);
  char ip[100];
  assert (read (auth_file_fd, ip, l) == l);
  ip[l] = 0;

  long long auth_key_id;
  static unsigned char auth_key[256];
  assert (read (auth_file_fd, &auth_key_id, 8) == 8);
  assert (read (auth_file_fd, auth_key, 256) == 256);

  //bl_do_add_dc (id, ip, l, port, auth_key_id, auth_key);
  bl_do_dc_option (id, 2, "DC", l, ip, port);
  bl_do_set_auth_key_id (id, auth_key);
  bl_do_dc_signed (id);
}

void empty_auth_file (void) {
  char *ip = tgl_state.test_mode ? TG_SERVER_TEST : TG_SERVER;
  bl_do_dc_option (1, 3, "DC1", strlen (ip), ip, 443);
  bl_do_set_working_dc (1);
}

int need_dc_list_update;
void read_auth_file (void) {
  if (binlog_enabled) { return; }
  int auth_file_fd = open (get_auth_key_filename (), O_CREAT | O_RDWR, 0600);
  if (auth_file_fd < 0) {
    empty_auth_file ();
    return;
  }
  assert (auth_file_fd >= 0);
  unsigned x;
  unsigned m;
  if (read (auth_file_fd, &m, 4) < 4 || (m != DC_SERIALIZED_MAGIC)) {
    close (auth_file_fd);
    empty_auth_file ();
    return;
  }
  assert (read (auth_file_fd, &x, 4) == 4);
  assert (x > 0);
  int dc_working_num;
  assert (read (auth_file_fd, &dc_working_num, 4) == 4);
  
  int i;
  for (i = 0; i <= (int)x; i++) {
    int y;
    assert (read (auth_file_fd, &y, 4) == 4);
    if (y) {
      read_dc (auth_file_fd, i, m);
    }
  }
  bl_do_set_working_dc (dc_working_num);
  int our_id;
  int l = read (auth_file_fd, &our_id, 4);
  if (l < 4) {
    assert (!l);
  }
  if (our_id) {
    bl_do_set_our_id (our_id);
  }
  close (auth_file_fd);
}

void read_secret_chat (int fd) {
  int id, l, user_id, admin_id, date, ttl, layer, state;
  long long access_hash, key_fingerprint;
  static char s[1000];
  static unsigned char key[256];
  assert (read (fd, &id, 4) == 4);
  //assert (read (fd, &flags, 4) == 4);
  assert (read (fd, &l, 4) == 4);
  assert (l > 0 && l < 1000);
  assert (read (fd, s, l) == l);
  assert (read (fd, &user_id, 4) == 4);
  assert (read (fd, &admin_id, 4) == 4);
  assert (read (fd, &date, 4) == 4);
  assert (read (fd, &ttl, 4) == 4);
  assert (read (fd, &layer, 4) == 4);
  assert (read (fd, &access_hash, 8) == 8);
  assert (read (fd, &state, 4) == 4);
  assert (read (fd, &key_fingerprint, 8) == 8);
  assert (read (fd, &key, 256) == 256);

  bl_do_encr_chat_create (id, user_id, admin_id, s, l);
  struct tgl_secret_chat  *P = (void *)tgl_peer_get (TGL_MK_ENCR_CHAT (id));
  assert (P && (P->flags & FLAG_CREATED));
  bl_do_encr_chat_set_date (P, date);
  bl_do_encr_chat_set_ttl (P, ttl);
  bl_do_encr_chat_set_layer (P, layer);
  bl_do_encr_chat_set_access_hash (P, access_hash);
  bl_do_encr_chat_set_state (P, state);
  bl_do_encr_chat_set_key (P, key, key_fingerprint);
}

void read_secret_chat_file (void) {
  if (binlog_enabled) { return; }
  int secret_chat_fd = open (get_secret_chat_filename (), O_CREAT | O_RDWR, 0600);
  if (secret_chat_fd < 0) { return; }
  //assert (secret_chat_fd >= 0);
  int x;
  assert (read (secret_chat_fd, &x, 4) == 4);
  assert (x == SECRET_CHAT_FILE_MAGIC);
  assert (read (secret_chat_fd, &x, 4) == 4);
  assert (!x); // version
  assert (read (secret_chat_fd, &x, 4) == 4);
  assert (x >= 0);
  while (x --> 0) {
    read_secret_chat (secret_chat_fd);
  }
  close (secret_chat_fd);
}

void dlist_cb (void *callback_extra, int success, int size, tgl_peer_id_t peers[], int last_msg_id[], int unread_count[])  {
  d_got_ok = 1;
}

int loop (void) {
  //on_start ();
  tgl_set_callback (&upd_cb);
  tgl_init ();
 
  if (binlog_enabled) {
    double t = tglt_get_double_time ();
    if (verbosity >= E_DEBUG) {
      logprintf ("replay log start\n");
    }
    tgl_replay_log ();
    if (verbosity >= E_DEBUG) {
      logprintf ("replay log end in %lf seconds\n", tglt_get_double_time () - t);
    }
    tgl_reopen_binlog_for_writing ();
  } else {
    read_auth_file ();
    read_state_file ();
    read_secret_chat_file ();
  }
  binlog_read = 1;
  #ifdef USE_LUA
    lua_binlog_end ();
  #endif
  update_prompt ();
    
  net_loop (0, all_authorized);

  int i;
  for (i = 0; i <= tgl_state.max_dc_num; i++) if (tgl_state.DC_list[i] && !tgl_authorized_dc (tgl_state.DC_list[i])) {
    assert (0);
  }

  if (!tgl_signed_dc (tgl_state.DC_working)) {
    if (!default_username) {
      size_t size = 0;
      char *user = 0;

      if (!user) {
        printf ("Telephone number (with '+' sign): ");         
        if (net_getline (&user, &size) == -1) {
          perror ("getline()");
          exit (EXIT_FAILURE);
        }
        set_default_username (user);
      }
    }
    tgl_do_send_code (default_username, sign_in_callback, 0);
    net_loop (0, sent_code);
   
    if (verbosity >= E_DEBUG) {
      logprintf ("%s\n", should_register ? "phone not registered" : "phone registered");
    }
    if (!should_register) {
      char *code = 0;
      size_t size = 0;
      printf ("Code from sms (if you did not receive an SMS and want to be called, type \"call\"): ");
      while (1) {
        if (net_getline (&code, &size) == -1) {
          perror ("getline()");
          exit (EXIT_FAILURE);
        }
        if (!strcmp (code, "call")) {
          printf ("You typed \"call\", switching to phone system.\n");
          tgl_do_phone_call (default_username, hash, 0, 0);
          printf ("Calling you! Code: ");
          continue;
        }
        if (tgl_do_send_code_result (default_username, hash, code, sign_in_result, 0) >= 0) {
          break;
        }
        printf ("Invalid code. Try again: ");
        free (code);
      }
    } else {
      printf ("User is not registered. Do you want to register? [Y/n] ");
      char *code;
      size_t size;
      if (net_getline (&code, &size) == -1) {
        perror ("getline()");
        exit (EXIT_FAILURE);
      }
      if (!*code || *code == 'y' || *code == 'Y') {
        printf ("Ok, starting registartion.\n");
      } else {
        printf ("Then try again\n");
        exit (EXIT_SUCCESS);
      }
      char *first_name;
      printf ("First name: ");
      if (net_getline (&first_name, &size) == -1) {
        perror ("getline()");
        exit (EXIT_FAILURE);
      }
      char *last_name;
      printf ("Last name: ");
      if (net_getline (&last_name, &size) == -1) {
        perror ("getline()");
        exit (EXIT_FAILURE);
      }
      printf ("Code from sms (if you did not receive an SMS and want to be called, type \"call\"): ");
      while (1) {
        if (net_getline (&code, &size) == -1) {
          perror ("getline()");
          exit (EXIT_FAILURE);
        }
        if (!strcmp (code, "call")) {
          printf ("You typed \"call\", switching to phone system.\n");
          tgl_do_phone_call (default_username, hash, 0, 0);
          printf ("Calling you! Code: ");
          continue;
        }
        if (tgl_do_send_code_result_auth (default_username, hash, code, first_name, last_name, sign_in_result, 0) >= 0) {
          break;
        }
        printf ("Invalid code. Try again: ");
        free (code);
      }
    }

    net_loop (0, signed_in);    
    //bl_do_dc_signed (tgl_state.DC_working);
  }

  for (i = 0; i <= tgl_state.max_dc_num; i++) if (tgl_state.DC_list[i] && !tgl_signed_dc (tgl_state.DC_list[i])) {
    tgl_do_export_auth (i, export_auth_callback, (void*)(long)tgl_state.DC_list[i]);    
    cur_a_dc = tgl_state.DC_list[i];
    net_loop (0, dc_signed_in);
    assert (tgl_signed_dc (tgl_state.DC_list[i]));
  }
  write_auth_file ();
  
  fflush (stdout);
  fflush (stderr);

  //read_state_file ();
  //read_secret_chat_file ();

  set_interface_callbacks ();

  tgl_do_get_difference (sync_from_start, get_difference_callback, 0);
  net_loop (0, dgot);
  assert (!(tgl_state.locks & TGL_LOCK_DIFF));
  if (wait_dialog_list) {
    d_got_ok = 0;
    tgl_do_get_dialog_list (dlist_cb, 0);
    net_loop (0, dgot);
  }
  #ifdef USE_LUA
    lua_diff_end ();
  #endif
  tglm_send_all_unsent ();


  /*tgl_do_get_dialog_list (get_dialogs_callback, 0);
  if (wait_dialog_list) {
    dialog_list_got = 0;
    net_loop (0, dlgot);
  }*/

  return main_loop ();
}