<?php

/**
 * @file
 * User facing page for booking into a variety session
 * NOTE: This feature is not complete
 */


function booking_variety_regn_form($node, &$form_state)
{
  global $event;
  $form = array ();
  $data = $node;

  // Query the variety timeslot table
  $timeslot_query = db_select('booking_variety_timeslots', 'v');	
  $timeslot_query->condition('v.booking_eventid', $event->eid, '=')
    ->fields('v')
    ->orderBy('v.booking_variety_start');
  $result = $timeslot_query->execute();            

  //$form['#prefix'] = '<div id="booking_variety_session_form_wrapper">';
  //$form['#suffix'] = '</div>'; 

  $form['identity'] = array(
    '#type' => 'fieldset',
    '#title' => 'Select Person',
  );

  $form['identity']['booking_nid'] = array(
    '#type' => 'textfield',
    '#title' => t('Booking Number'),
    '#description' => t('Please enter your booking number from your lanyard.'),
    '#size' => 60,	
    '#required' => TRUE,
    '#default_value' => !empty($data->booking_nid) ? $data->booking_nid : '',
    '#ajax' => array(
      'event' => 'change',
      'wrapper' => 'booking_variety_session_fieldset_wrapper',
      'callback' => 'booking_variety_session_form_callback',
    ),	      
  );

  $form['variety-sessions'] = array(
    '#type' => 'fieldset',
    '#title' => 'Select Variety Sessions',
    '#prefix' => '<div id="booking_variety_session_fieldset_wrapper">',
    '#suffix' => '</div>'
  );  

  //for each entry in the variety timeslot table, create a new form select item
  foreach($result as $timeslot) {
    $fieldname = 'select-variety-' . $timeslot->tid;

    // Make sure we get rid of any stale data
    /*
    if (isset($form_state['input']['variety-sessions'][$fieldname])) {
      watchdog('booking_debug', 'Unsetting stale @name data, was: <pre>@info</pre>', 
        array('@name' => $fieldname, '@info' => print_r($form_state['input'], true)));
      unset($form_state['input']['variety-sessions'][$fieldname]);
    }
    */

    //create the form element for this timeslot
    $form['variety-sessions'][$fieldname] = array(
      '#type' => 'select',
      '#title' => t('Variety Session: ' . $timeslot->booking_variety_time_descrip),
      '#required' => TRUE,
      '#default_value' => isset($form_state['values'][$fieldname]) ? $form_state['values'][$fieldname] : 0,
      '#options' => _booking_get_variety_timeslot_options($timeslot->tid),
      '#prefix' => '<div id="booking_variety_session_' . $timeslot->tid . '_wrapper">',
      '#suffix' => '</div>',          
    );
  }	
  
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );	

  return array (
    'form' => $form,
  );
}

/**
 * Function to calculate available variety sessions for ajax enabled form booking_variety_regn_form()
 * @param $timeslot_id - the timeslot ID to query
 * @return array containing the variety sessions for specified timeslot that still have capacity
 */
function _booking_get_variety_timeslot_options($timeslot_id) {
  $session_options = array();
  $session_options[] = "--";
  
  $session_query = db_query("SELECT * FROM {booking_variety_sessions} WHERE booking_variety_timeslot_id = :tid AND booking_variety_status = 1",
    array(':tid' => $timeslot_id));
  
  // Only add sessions that aren't full to the return result
  foreach($session_query as $session) {
    $available_spots = $session->booking_variety_maxsize - $session->booking_variety_regncount;
    if ($available_spots > 0) {
      $session_options[$session->vid] = $session->booking_variety_descrip . " [" . $available_spots . " spots]";
    }
  }	
  //watchdog('booking_debug', "<pre>Variety Session Options:\n@info</pre>", array('@info' => print_r( $session_options, true)));
  
  return $session_options;
}


/**
 * Callback function to rebuild the variety session fieldset
 */
function booking_variety_session_form_callback($form, &$form_state) {
  $form_state['rebuild'] = TRUE;
  return $form['form']['variety-sessions'];
}

/**
 * Validate the submission 
 */
function booking_variety_regn_form_validate($form, &$form_state) {
	global $event;
  $values = $form_state['input'];	
  //watchdog('booking_debug', 'booking_variety_regn_form_validate: <pre>@info</pre>', array('@info' => print_r( $form_state, true)));

  // Don't run validation on ajax callback
  if (isset($form_state['input']['_triggering_element_name'])) {
    //watchdog('booking_debug', 'booking_variety_regn_form_validate: skipping due to ajax callback');
    return;
  }

  //verify that user-entered data is a number
  if (! preg_match('/^[0-9]+$/', $values['booking_nid'])) {
    form_set_error('booking_nid', t('You have entered an invalid booking reference number.'));
  }	    

  // Perform lookup on barcode to make sure it matches someone attending the current event
  $db_and = db_and();
  $db_and->condition('p.booking_eventid', $event->eid, '=');
  $db_and->condition('p.booking_status', 1, '=');
  $db_and->condition('p.nid', $values['booking_nid'], '=');

  $query = db_select('booking_person', 'p');
  $query->condition($db_and)
    ->fields('p');
  $person = $query->execute()
    ->fetchObject();  

  if (! $person) {
    form_set_error('booking_nid', t('You have entered an invalid booking reference number.'));
  }

  // --- Check there is still space available in the selected variety sessions ---

  //get a list of timeslot IDs from matching form values
  $variety_timeslot_ids = preg_filter('/^select-variety-(\d+)/', '$1', array_keys( $values ));

  //query the sessions table
  $sessions_query = db_query("SELECT * FROM {booking_variety_sessions} WHERE booking_eventid = :eid", 
    array(':eid' => $event->eid));
  $sessions = $sessions_query->fetchAllAssoc('vid');

  //watchdog('booking_debug', 'booking_variety_regn_form_validate sessions query: <pre>@info</pre>', array('@info' => print_r( $sessions, true)));

  //check there is still room 
  foreach ($variety_timeslot_ids as $id) {
    $selected_session_id = $values['select-variety-' . $id];

    // Don't try and check availablity for a select element that is still on the default value
    if ($selected_session_id == 0) {
      form_set_error('select-variety-' . $id, t('You have not selected a variety session.'));
      continue;
    }

    $session = $sessions[$selected_session_id];
    if ($session->booking_variety_regncount >= $session->booking_variety_maxsize) {
      //watchdog('booking_debug', 'No room in session @id : @count is less than @size', array(
      //  '@id' => $selected_session_id, '@count' => $session->booking_variety_regncount,
      //  '@size' => $session->booking_variety_maxsize
      //));
      $form_state['rebuild'] = TRUE;
      $form_state['flag'] = 1;      
      drupal_set_message('You have selected a session that is now full. Please try again.', 'error', FALSE);
    }
  }
}

/**
 * Process the submission 
 */
function booking_variety_regn_form_submit($form, &$form_state) {
	global $event;
  $values = $form_state['input'];	
  watchdog('booking_debug', 'booking_variety_regn_form_submit: <pre>@info</pre>', array('@info' => print_r( $form_state, true)));
  $booking_variety_ids = array();


  //get a list of timeslot IDs from matching form values
  $variety_timeslot_ids = preg_filter('/^select-variety-(\d+)/', '$1', array_keys( $values ));

  //query the sessions table
  $sessions_query = db_query("SELECT * FROM {booking_variety_sessions} WHERE booking_eventid = :eid", 
    array(':eid' => $event->eid));
  $sessions = $sessions_query->fetchAllAssoc('vid');

  foreach ($variety_timeslot_ids as $id) {
    $selected_session_id = $values['select-variety-' . $id];

    // Don't try and check availablity for a select element that is still on the default value
    if ($selected_session_id == 0) {
      continue;
    }

    //use an update query for the regncount field
    //idea from https://api.drupal.org/comment/19374#comment-19374
    db_update('booking_variety_sessions')
      ->expression('booking_variety_regncount', 'booking_variety_regncount + :count', array(':count' => 1))
      ->condition('vid', $selected_session_id)
      ->execute();    

    //store the selected variety sessions in an array of IDs
    $booking_variety_ids[] = $selected_session_id;
  }

  //perform the insert to the booking_variety_regn table
  db_insert('booking_variety_regn')
    ->fields(array(		
      'booking_variety_ids' => implode(",", $booking_variety_ids),
      'booking_person_nid' => $values['booking_nid'],
    ))
    ->execute();
}