<?php
/*
 * codice schifo del GOLEMbot - dal 28 set 2017
 *
 * Opera by giomba, lucam e giuliof released under GPLv3 license
 *
 */

require_once('/data/config.php');
require_once('shared.php');

// === BEGIN ===

DEBUG and botlog('[II] BOT request starting at ' . date('Y-m-d H:i:s'));

$json = file_get_contents('php://input');
$row  = json_decode($json);

DEBUG and botlog("[II] Incoming JSON ".$json."\n");

// Start up Memcached
$mc = new Memcached();
if ($mc == null) error('no memcached object instance');
if (! $mc->addServer(MEMCACHED_HOST, MEMCACHED_PORT)) {
    error("something is wrong connecting to memcached daemon");
}

// Structure of managed telegram messages
/*
 * **Generic message**
 * $row
 * |_ message § Message
 *    |_ message_id § integer
 *    |_ chat § chat
 *       |_ id (chatID) § integer
 *       |_ username (if set - user name for private chat, else channel or group name) § string
 *       |_ ...not relevant things...
 *    |_ from § User
 *       |_ id (userID) § integer
 *       |_ username (if set - user name) § string
 *       |_ ....
 *    |_ forward_from § User
 *    |_ forward_from_chat § Chat
 *    |_ text § string (message_text)
 *    |_ entities: [{"offset":...,"length":...,"type":"italic"}]
 *    |_ photo, location, video
 *
 * **Callback Query**
 * $row
 * |_ callback_query
 *    |_ id § integer
 *    |_ from § User
 *    |_ message § Message
 *    |_ inline_message_id § integer (inlineID)
 *    |_ ...
 */

// HANDLE A CALLBACK
if (isset ($row->callback_query)) {
DEBUG and botlog('handle callback query');
  $chatID = $row->callback_query->message->chat->id;

  // Check if it was thrown by admitted users
  in_array($row->callback_query->message->chat->username, BOT_ALLOWED_USERS) or not_authorized($chatID);
  botlog('Ok authorized user pass!');

  // Answer to the callback query (remove the loading sign)
  info("Callback Query, answering");
  $url = API_URL.API_TOKEN."/answerCallbackQuery?callback_query_id=".$row->callback_query->id;
  file_get_contents($url);

  // Do something - insert here useful variables
  $callback_data = $row->callback_query->data;

  $inlineID = $row->callback_query->message->message_id;
  $inlineID_old = $mc->get($chatID.MC_INLINE_ID);

  // check if request comes from active inline item
  if ($inlineID != $inlineID_old) { // expired session
  // If called callback comes from an old inline item do not answer
    if (DEBUG) warning("That's an old callback!");
    die();
  }

  // Finally, check actual state and do things
  $status = $mc->get($chatID.MC_STATUS);
    if (!$status) {
      $mc->set($chatID.MC_STATUS, STATE_IDLE) or die(); // set status or force it to STATE_IDLE
      $status = STATE_IDLE;
    }
  if (DEBUG) info("Starting from status $status");


  // Callback state machine
  switch ($status) {
   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    *  entering STATE_IDLE - callback                                 *
    *  you can: list and delete messages given by /list               *
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
    case STATE_IDLE:
        switch ($callback_data){
          case MSG_DELETE:

            // remove current message
              $sql = new Sqlite3(DBFILE);
            $IDdelete = $mc->get($chatID.MC_DELETE_SCHEDULED_ID) or error("No ID to delete");
            $sql->query("DELETE FROM telegram_post WHERE ID=$IDdelete")
            or error("Can't make the query, SQL error ".$sql->lastErrorMsg());

            $sql->close();

            $offset = $mc->get($chatID.MC_LIST_NUMBER);

            if ($offset > 0) {
              $offset--;
            }
            break;
          case '>':
            $offset = $mc->get($chatID.MC_LIST_NUMBER);
            $offset++;  // nobody cares if goes over # of programmed messages
            break;
          case '<':
            $offset = $mc->get($chatID.MC_LIST_NUMBER);
            if ($offset > 0)
              $offset--;
            break;
          default:
            if (DEBUG) warning("Callback request is not accepted in status $status");
            die();
          }

          $archivedMsg = navigateMsgArchive($offset, $mc, $chatID);

          $answer = editMessageText($chatID, $inlineID, $archivedMsg['text'],
                    "HTML", false, $archivedMsg['kbd'] );
          $answer = json_decode($answer);

          $mc->set($chatID.MC_LIST_NUMBER, $offset)
          or $mc->replace($chatID.MC_LIST_NUMBER, $offset);

          die();
      break;
   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * END STATE_IDLE
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * entering STATE_MSG_ANSWER - callback
    * you can: (after you sent a message) choose if forward to
    *   channel or schedule it
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

    case STATE_MSG_ANSWER: // only accessible by callback

    /////// spostare di là
      if (!(isset($callback_data))) {
        //$mc->replace($chatID.MC_STATUS, STATE_IDLE);
        wrong_action($chatID);
        die();
      }

      switch ($callback_data) {
        case MSG_YES:
          // forward previously sent message
          // set status?
          $mc->replace($chatID.MC_STATUS, STATE_IDLE)
            or error("Something is wrong with memcached");
          $msg = $mc->get($chatID.MC_FORWARD_MSG)
            or error("Can't forward message\n");

          forwardMessage(API_CHANNEL_ID, $msg->message->chat->id, $msg->message->message_id, FORWARD_SILENT);

          // Remove kbd
          $text = "Invio effettuato correttamente";
          editMessageText($chatID, $inlineID, $text);
          //~ $url = API_URL.API_TOKEN."/editMessageText?chat_id=".($chatID).
            //~ "&message_id=".$inlineID .
            //~ "&text=".urlencode($text);
            //~ file_get_contents($url);
          break;

        case MSG_NO:
          $status = $mc->replace($chatID.MC_STATUS, STATE_IDLE)
            or error("Something is wrong with memcached");

          // destroy saved message?
          $text = "Invio annullato correttamente";
          editMessageText($chatID, $inlineID, $text);
          break;

        case MSG_SCHEDULE:
            // == from here can be put in a function ==
          info('status MSG_SCHEDULE');
          $status = $mc->replace($chatID.MC_STATUS, STATE_WAIT_DATE) or error(__FILE__ . __LINE__);
          $currentTab = array(
            'month' => date('n'),
            'year' =>  date('Y'),
            'day'  => null
          );

          $reply = getCalendarTab($currentTab['month'], $currentTab['year']);
          info('calendar tab: ' . $reply);

          $mc->set($chatID.MC_DATE_MSG, $currentTab) or $mc->replace($chatID.MC_DATE_MSG, $currentTab)  or  error(__FILE__ . __LINE__);

          $text="Quando vuoi inviare il messaggio?";
          editMessageText($chatID, $inlineID, $text, "HTML", false, $reply);

          $mc->set($chatID.MC_INLINE_ID, $inlineID) or $mc->replace($chatID.MC_INLINE_ID, $inlineID)
            or error("Something is wrong with memcached");
          // == end ==
          break;
      }
    break;
   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * END STATE_MSG_ANSWER
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * entering STATE_WAIT_DATE - callback
    * you can: choose the date of scheduled message(s)
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
    case STATE_WAIT_DATE:
      $currentTab = $mc->get($chatID.MC_DATE_MSG)
        or error("Something is wrong with memcached");

      // two cases: change page or confirm date
      if ($callback_data == '>') {
        // add 1 to month
        if ($currentTab['month'] < 12)
        $currentTab['month'] +=1;
        else {
        $currentTab['month'] = 1;
        $currentTab['year'] +=1;
        }
        $mc->set($chatID.MC_DATE_MSG, $currentTab) or $mc->replace($chatID.MC_DATE_MSG, $currentTab)
         or error("Something is wrong with memcached");

        $text = "Il calendario del ".$currentTab['month']."-".$currentTab['year'];

        // get new inline container
      }
      elseif ($callback_data == '<') {
        if ($currentTab['month'] > 1)
        $currentTab['month'] -=1;
        else {
        $currentTab['month'] = 12;
        $currentTab['year'] -=1;
        }
        $text = "Il calendario del ".$currentTab['month']."-".$currentTab['year'];

        $mc->set($chatID.MC_DATE_MSG, $currentTab) or $mc->replace($chatID.MC_DATE_MSG, $currentTab)
         or error("Something is wrong with memcached");
      }
      elseif ($callback_data == 'null') {
        // not a valid button (like week days buttons)
        die();
      }
      elseif ($callback_data == MSG_ABORT) {
        $text = "Invio annullato correttamente";
        editMessageText($chatID, $inlineID, $text);
        $mc->replace($chatID.MC_STATUS, STATE_IDLE) or die();
        die();
      }
      else {
        // read current day, verify it and then change state
        if (!$callback_data = intval($callback_data))
          error("Not a numerical day, how you did it?!?");
        $currentTab['day'] = $callback_data;
        $mc->set($chatID.MC_DATE_MSG, $currentTab) or $mc->replace($chatID.MC_DATE_MSG, $currentTab)  or  die ("Failed to save data at Memcached server");

        // Display time inline keyboard
        $kbd = new InlineKbd;

        $firstHour = date('Ynj') ==  $currentTab['year'].$currentTab['month'].$currentTab['day']?
        date('G')+1 : 8;

        for ($i = 8; $i <= 21; $i++) {
          if ($i < $firstHour)
            $kbd->insertItem(" ", "null");
          else
            $kbd->insertItem("$i".":00", $i);

          if ($i == 14)
          $kbd->pushLine();
        }
        $kbd->pushLine();

        $kbd->insertItem("$EMOJI_X Annulla", MSG_ABORT);

        $kbd->pushLine();


        $text="A che ora vuoi inviare il messaggio?";

        //~ $url = API_URL.API_TOKEN."/editMessageText?chat_id=".($chatID).
          //~ "&message_id=".$inlineID .
          //~ "&text=".urlencode($text)."&reply_markup=".$reply;
        //~ file_get_contents($url);

        editMessageText($chatID, $inlineID, $text, "HTML",
              false, $kbd->getKeyboard());

        $mc->replace($chatID.MC_STATUS, STATE_WAIT_TIME) or die();
        break;
      }

      // If answer is < or > remain in current state and update calendar
      $reply = getCalendarTab($currentTab['month'], $currentTab['year']);

      //~ $url = API_URL.API_TOKEN."/editMessageText?chat_id=".($chatID).
        //~ "&message_id=".$inlineID .
        //~ "&text=".urlencode($text)."&reply_markup=".$reply;
      //~ file_get_contents($url);
      editMessageText($chatID, $inlineID, $text, "HTML", false, $reply);

      $mc->set($chatID.MC_INLINE_ID, $inlineID) or $mc->replace($chatID.MC_INLINE_ID, $inlineID);

      break;
   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * END STATE_WAIT_DATE
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

   /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * entering STATE_WAIT_TIME - callback
    * you can: choose the time of scheduled message(s)
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
    case STATE_WAIT_TIME:
      $mc->replace($chatID.MC_STATUS, STATE_IDLE);
      if ($callback_data == MSG_ABORT) {
        $text = "Invio annullato correttamente";
        editMessageText($chatID, $inlineID, $text);
        $mc->replace($chatID.MC_STATUS, STATE_IDLE) or die();
        die();
      }
      elseif (!$time = intval($callback_data)) {
          if (DEBUG) botlog("[EE] Not a numeric time\n");
          die();
      }

      $currentTab = $mc->get($chatID.MC_DATE_MSG);
      $msg = $mc->get($chatID.MC_FORWARD_MSG);


      // Message preview in scheduling list is not formatted!
      $text = htmlspecialchars($msg->message->text);


      $dateObj = DateTime::createFromFormat('Y-n-j-G-e', $currentTab['year'] . '-' . $currentTab['month'] . '-' . $currentTab['day'] . '-' . $callback_data . '-Europe/Rome');
      $dateObj->setTimezone(new DateTimeZone('UTC'));
      $formattedDate = $dateObj->format('Y-m-d H:i:s');


      // add to database (mysql)
      $sql = new SQLite3(DBFILE);
      // Build up mysql query
      $value  = "(";
      $value .= $msg->message->message_id;
      $value .= ",";
      $value .= $msg->message->chat->id;
      $value .= ",";
      $value .= "'$formattedDate'";
      $value .= ",";
      if (isset($text))
        $value .= "'".$sql->escapeString($text)."'";
      else
        $value .= "''";
      $value .= ",";
      if (isset($msg->message->forward_from->username))
        $value .= "'".$sql->escapeString($msg->message->forward_from->username)."'";
      elseif (isset($msg->message->from->username))
        $value .= "'".$sql->escapeString($msg->message->from->username)."'";
      else
        $value .= "''";
      $value .= ");";

      $query = "INSERT INTO telegram_post (MessageID,ChatID,DateTime,Text,Author) VALUES ".$value;
      info('saving post in database, query: ' . $query);
      $sql->query($query) or error("Can't make the query, SQL error ".$sql->lastErrorMsg());
      $sql->close();

      $text = "Programmazione avvenuta con successo";

      editMessageText($chatID, $inlineID, $text);

      break;
  }
    /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
    * END STATE_WAIT_TIME
    * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
}


// HANDLE A COMMON MESSAGE (text/commands/photos...)
elseif (isset($row->message)) {
    info('handling common message');
  // Load variables
  $chatID = $row->message->chat->id;
  // Check if it was thrown by admitted users
if (in_array($row->message->from->username, BOT_ALLOWED_USERS)) {
    info('authorized user ok');

    // Finally, check actual state and do things
    $status = $mc->get($chatID.MC_STATUS);
    if (!$status) {
      $mc->set($chatID.MC_STATUS, STATE_IDLE) or die(); // set status or force it to STATE_IDLE
      $status = STATE_IDLE;
    }
    info("Starting from status $status");

    // Reset CMD
    if (($command = getCommand($row->message))['command'] == '/reset') {
      warning("Reset command received");
      $all_keys = $mc->getAllKeys();
      foreach ($all_keys as $index => $key) {
        if (strpos($key,$chatID) !== 0) {
          $mc->delete($key);
          info("Deleting $key");
        }
        else {
          unset($all_keys[$index]);
        }
      }
      sendMessage($chatID, "Reset completato");
    }
    else {
      switch($status) {
       /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
        *  entering STATE_IDLE - message                                  *
        *  you can: give a command, send messages to forward              *
        * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
        case STATE_IDLE:
          if (($command = getCommand($row->message)) != null) {
            info("Command received: $command[command] with options $command[options]");

            switch ($command['command']) {
              case '/help':
              case '/start':
                // Send some explainations about this bot
                sendMessage($chatID,$WELCOME_MESSAGE, "HTML");
              break;

              case '/edit':
                // not yet implemented
                sendMessage($chatID, "Bravo! Hai trovato un comando non ancora implementato. Apri il codice su GitHub e lavoraci su");
              break;

              case '/list':

                $archivedMsg = navigateMsgArchive(0, $mc, $chatID);

                $answer = sendMessage($chatID, $archivedMsg['text'], "HTML", false, false, null, $archivedMsg['kbd']);
                $answer = json_decode($answer);
                // Should forward the message if is not pure text
                //forwardMessage($chatID, $row['ChatID'], $row['MessageID']);


                $mc->set($chatID.MC_INLINE_ID, $answer->result->message_id)
                or $mc->replace($chatID.MC_INLINE_ID, $answer->result->message_id);

                $mc->set($chatID.MC_LIST_NUMBER, 0)
                or $mc->replace($chatID.MC_LIST_NUMBER, 0);
              break;

              default:
                sendMessage($chatID,"Non è un comando valido, leggi i comandi digitando /help");
                warning("$command[command] is not a valid command");
            }
          }
          else { // not a command (text?)
            // you probably want to forward a message?

            // Check what kind of message is this
            $kbd = new InlineKbd;
            $kbd->insertItem("SI ".$EMOJI_THUMBSUP,MSG_YES);
            $kbd->insertItem("NO ".$EMOJI_THUMBSDOWN,MSG_NO);
            $kbd->insertItem("Programma ".$EMOJI_CLOCK,MSG_SCHEDULE);
            $kbd->pushLine();

            // This bot accepts only text, images, videos and locations
            if (!(isset($row->message->photo) or isset($row->message->location)
            or isset($row->message->video) or isset($row->message->text) )) {
              sendMessage($chatID, "Questa roba non va bene");
              error("Not supported content");
              // Program stops here
            }

            $mc->set($chatID.MC_FORWARD_MSG, $row)
              or $mc->replace($chatID.MC_FORWARD_MSG, $row)
              or error("Something is wrong with memcached");

            // SetUp inline messages (OK, NO, SCHEDULE)

            $text="Vuoi condividere sul canale?"; // NOME CANALE ".API_CHANNEL_ID."?";

            $query = sendMessage($row->message->chat->id,
                                 $text,
                                 null, false, false, null,
                                 $kbd->getKeyboard());

            //~ $answer = file_get_contents($query);
            $answer = json_decode($query);

            $inlineID = $answer->result->message_id;
            if (DEBUG) info("Callback message id: $inlineID");


            $mc->replace($chatID.MC_STATUS, STATE_MSG_ANSWER);
            $mc->set($chatID.MC_INLINE_ID, $inlineID) or $mc->replace($chatID.MC_INLINE_ID, $inlineID);
          }
          break;
       /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
        * END STATE_IDLE
        * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

        default:
          wrong_action($chatID);
      }
    }
  }
  else
    not_authorized($chatID);
}
// a not supported message (i.e. from a channel)
else {
  error("This is not a supported request. Please check JSON dump");
}
?>