allocated_seating module

<?php
// $Id$
/*
 * @file allocated_seating.module
 * Provides form elements to enable other modules to define allocated seating
 * and collect user input
 * @copyright Copyright(c) 2010 Lee Rowlands
 * @license GPL v2 http://www.fsf.org/licensing/licenses/gpl.html
 * @author Lee Rowlands leerowlands at rowlands-bcs dot com
 *
 */

/**
 * Implementation of hook_menu().
 */
function allocated_seating_menu() {
  //generic Call handler, append args to return specific form elements

  $items['allocated_seating/ajax'] = array(
    'title'            => 'Generic Call handler',
    'delivery callback' => 'drupal_json_output',
    'page callback'    => 'allocated_seating_ajax',
    'access arguments' =>  array('create seating plans'),
    'type'             => MENU_CALLBACK
  );
  return $items;
}


/**
 * Implements hook_permission
*/

function  allocated_seating_permission() {
  return array(
    'create seating plans' => array(
      'title' => t('Create seating plans'),
    )
  );
}

/**
 * Implementation of hook_elements_info().
 */
function allocated_seating_element_info() {
  $type['allocated_seating_seat_design'] = array(
    '#input' => TRUE,
    '#tree' => TRUE,
    '#default_value' => array(
      'seats' => 40,
      'row_count' => 2,
      'floor_count' => 1,
      'floors' => array(),
    ),
    '#process' => array('allocated_seating_seat_design_process'),
    '#theme' => array('allocated_seating_seat_design'),
  );

  $type['allocated_seating_seat_select'] = array(
    '#input' => TRUE,
    '#tree' => TRUE,
    '#process' => array('allocated_seating_seat_select_process'),
    '#element_validate' => array('allocated_seating_seat_select_validate'),
    '#required_seats' => NULL,
  );
  return $type;
}


/**
 * Implementation of hook_theme().
 */
function allocated_seating_theme($existing, $type, $theme, $path) {
  return array(
    'allocated_seating_seat_design' => array(
      'arguments' => array('element' => NULL),
    ),
    'allocated_seating_seat_select' => array(
      'arguments' => array('element' => NULL),
    ),
    'allocated_seating_seat_available' => array(
      'arguments' => array('plan' => array(),
                           'not_available' => array()
                          ),
    ),
  );
}

/**
 * Provides processing to expand the form element
*/
function allocated_seating_seat_select_process($element, $form_state, $complete_form) {
  if (empty($element['#plan'])) {
    //no floor plan!
    return;
  }
  $plan = $element['#plan'];
  if (!$element['#not_available']) {
    $element['#not_available'] = array();
  }
  $blank = 1;
  $parents = $element['#parents'];
  $element['floors'] = array(
    '#tree' => FALSE, //we structure the data in a nest for theming but only want seat# => 1/0
    '#parents' => array_merge($parents, array('floors'))
  );
  foreach ($plan['floors'] as $f => $floor) {
    $element['floors'][$f] = array(
      '#tree' => FALSE,
      '#col_count' => $floor['col_count'],
      'title' => array(
        '#value' => $floor['title']
      ),
      'rows' => array(
        '#tree' => FALSE,
      )
    );
    foreach ($floor['rows'] as $r => $row) {
      $element['floors'][$f]['rows'][$r] = array(
        '#tree' => FALSE,
        'columns' => array(
          '#tree' => FALSE,
          '#parents' => array_merge($parents, array('floors', $f, 'rows', $r, 'columns')),
        )
      );
      foreach ($row['columns'] as $c => $column) {
        if ($column['seat'] &&
            is_numeric($column['seat']) &&
            !in_array($column['seat'], $element['#not_available'])) {
          //add the seat checkbox
          $element['floors'][$f]['rows'][$r]['columns'][$column['seat']] = array(
            '#attributes' => array('class' => 'allocated-seating-seat'),
            '#type' => 'checkbox',
            '#parents' => array('seats', $column['seat']),
            '#title' => $column['seat']
          );
        }
        else {
          //add the blank
          $element['floors'][$f]['rows'][$r]['columns']['b_'. $blank] = array(
            '#value' => '&nbsp;'
          );
          $blank++;
        }
      }
    }
  }
  return $element;
}

/**
 * Provides processing to expand the form element
*/
function allocated_seating_seat_design_process($element, $form_state, $complete_form) {
  static $plan,$post_static;
  // Cache the submitted $_POST data.
  if (!empty($element['#post']) || $post_static === NULL) {
    if (count($element['#array_parents']) == 1) {
      $post = &$element['#post'][$element['#array_parents'][0]];
      $post_static = $element['#post'][$element['#array_parents'][0]];
    }
    elseif (count($element['#array_parents']) == 2) {
      $post = &$element['#post'][$element['#array_parents'][0]][$element['#array_parents'][1]];
      $post_static = $element['#post'][$element['#array_parents'][0]][$element['#array_parents'][1]];
    }
    elseif (count($element['#array_parents']) == 3) {
      $post = &$element['#post'][$element['#array_parents'][0]][$element['#array_parents'][1]][$element['#array_parents'][2]];
      $post_static = $element['#post'][$element['#array_parents'][0]][$element['#array_parents'][1]][$element['#array_parents'][2]];
    }
    else {
      $post = array();
      $post_static = array();
    }
  }
  $all_defaults = array();
  $all_defaults['allocated_seating_seat_design'] = element_info('allocated_seating_seat_design');
  $defaults = $all_defaults['allocated_seating_seat_design']['#default_value'];
  // Ensure there are correct defaults.
  foreach ($all_defaults['allocated_seating_seat_design']['#default_value'] as $var => $default) {
    if (empty($element['#value'][$var])) {
      $element['#value'][$var] = $default;
    }
  }
  if (empty($element['#seats'])) {
    //must know the # of seats!
    return array(
      '#value' => t('Did not receive number of seats for the design, cannot proceed. Please set the #seats element attribute.')
    );
  }
 if (empty($plan)) {
    if (empty($element['#value']['floors'])) {
    $default = array(
      'floors' => array(
        array(
          'title' => t('Floor 1'),
          'rows' => array()
        )
      )
    );//the default
    $cols = ceil($element['#seats'] / 4); //default 4 rows
    $row = 0;
    $s = 1;
    while ($row < 4) {
      $col = 0;
      $default['floors'][0]['rows'][$row] = array('columns' => array()); //add the rows
      while ($col < $cols) {
        if ($s <= $element['#seats']) {
          $seat = $s;
          $s++;
        }
        else {
          $seat = FALSE;
        }
        $default['floors'][0]['rows'][$row]['columns'][] = array('seat' => $seat); //add the seat
        $col++;
      }
      $row++;
    }
    $element['#value'] = $default;
  }
  else {
      // Check if a new floor needs to be added.
      if (!empty($form_state['post']['_triggering_element_name']) && $form_state['post']['_triggering_element_value'] == t('Add floor')) {
        $element['#value'] =  $_POST['ticket_plan'];
        allocated_seating_plan_add_floor($element, $post);
      }
    //make sure our seats matches the number in the plan
    $real_seats = allocated_seating_real_seats($element['#value']);
    $needed_seats = $element['#seats'];
    //do we have enough?
    $total_seats = allocated_seating_plan_seats($element['#value']);
    while ($total_seats < $needed_seats) {
      allocated_seating_plan_floor_add_row($element['#value'], 0);
      $total_seats = allocated_seating_plan_seats($element['#value']);
    }
    if ($needed_seats != $real_seats) {
      //we have an issue here
      $seat_map = allocated_seating_get_map($element['#value']);
      $blanks = $seat_map['blanks'];
      if ($needed_seats < $real_seats) {
        //we need to remove some seats
        while ($needed_seats < $real_seats) {
          $remove = $seat_map['seats'][$real_seats];
          if ($remove) {
            $element['#value']['floors'][$remove['floor']]['rows'][$remove['row']]['columns'][$remove['column']]['seat'] = FALSE;
          }
          $real_seats--;
        }
      }

      else {
        //we need to add some
        while ($needed_seats > $real_seats) {
          $real_seats++;
          $blank = array_shift($blanks);
          $element['#value']['floors'][$blank['floor']]['rows'][$blank['row']]['columns'][$blank['column']]['seat'] = $real_seats;
        }
      }
    }
  }

  $plan = $element['#value'];
}
  $parents = $element['#parents'];
  $element['floors'] = array(
    '#prefix' => '<div id="as-wrap-'. $element['#id'] .'">',
    '#suffix' => '</div>'
  );
  if ($form_state['storage']['type']) {
    $total_seats = allocated_seating_total_seats($plan);
    if ($total_seats < $element['#seats']) {
      form_set_error(implode('][', $element['#parents']), t('The entered row and column combination is not sufficient to meet the required number of seats, please try again'));
    }
    switch ($form_state['storage']['type']) {
      case 'row':
        $floor = $form_state['storage']['floor'];
        $current_rows = $original_rows = count($plan['floors'][$floor]['rows']);
        $row_count = $plan['floors'][$floor]['row_count'];
        while ($current_rows < $row_count) {
          allocated_seating_plan_floor_add_row($plan, $floor);
          $current_rows++;
        }
        while ($current_rows > $row_count) {
          allocated_seating_plan_remove_row($plan, $floor);
          $current_rows--;
        }
        break;

      case 'column':
        $floor = $form_state['storage']['floor'];
        $current_cols = $original_cols = count($plan['floors'][$floor]['rows'][0]['columns']);
        $col_count = $plan['floors'][$floor]['col_count'];
        if ($col_count > 23) {
          form_set_error('', t('The seating designer does not support more than 23 columns.'));
          $col_count = 23;
        }
        while ($current_cols < $col_count) {
          allocated_seating_plan_floor_add_column($plan, $floor);
          $current_cols++;
        }
        while ($current_cols > $col_count) {
          allocated_seating_plan_remove_column($plan, $floor);
          $current_cols--;
        }
        break;
    }
    unset($form_state['storage']['type'], $form_state['storage']['floor']);
  }
  foreach ($plan['floors'] as $f => $floor) {
    $element['floors'][$f] = array(
      '#tree' => TRUE,
      '#parents' => array_merge($parents, array('floors', $f)),
      'title' => array(
        '#type'          => 'textfield',
        '#title'         => t('Floor title'),
        '#parents' => array_merge($parents, array('floors', $f, 'title')),
        '#default_value' => t('Floor !floor', array('!floor' => $f + 1)),
        '#size'          => 10,
        '#maxlength'     => 50,
        '#required'      => TRUE,
      ),
      'row_count' => array(
        '#type'          => 'textfield',
        '#title'         => t('Rows'),
        '#parents' => array_merge($parents, array('floors', $f, 'row_count')),
        '#default_value' => count($floor['rows']),
        '#size'          => 10,
        '#maxlength'     => 10,
        '#required'      => TRUE,
        '#ajax' => array(
          'path' => 'allocated_seating/ajax/row/'. $f + 1 .'/'. $element['#ajax_extra'] . implode('/', $parents),
          'wrapper' => 'as-wrap-'. $element['#id'],
          'event' => 'change',
          'method' => 'replace',
          'effect' => 'fade',
        ),
      ),
      'col_count' => array(
        '#type'          => 'textfield',
        '#title'         => t('Columns'),
        '#parents'       => array_merge($parents, array('floors', $f, 'col_count')),
        '#default_value' => count($floor['rows'][0]['columns']),
        '#size'          => 10,
        '#maxlength'     => 10,
        '#required'      => TRUE,
        '#ajax' => array(
          'event' => 'change',
          'path' => 'allocated_seating/ajax/column/'. $f + 1 .'/'. $element['#ajax_extra'] . implode('/', $parents),
          'wrapper' => 'as-wrap-'. $element['#id'],
          'method' => 'replace',
          'effect' => 'fade',
        ),
      ),
      'remove_floor' => array(
        '#type' => 'submit',
        '#value' => t('Remove floor '). ($f + 1),
        '#submit' => array('allocated_seating_design_remove_floor'),
        '#ajax' => array(
          'path' => 'allocated_seating/ajax/floor/'. $element['#ajax_extra'] . implode('/', $parents),
          'wrapper' => 'as-wrap-'. $element['#id'],
          'method' => 'replace',
          'effect' => 'fade',
        )
      ),
      'rows' => array(
        '#tree' => TRUE,
        '#parents' => array_merge($parents, array('floors', $f, 'rows')),
      )
    );
    foreach ($floor['rows'] as $r => $row) {
      $element['floors'][$f]['rows'][$r] = array(
        '#tree' => TRUE,
        '#parents' => array_merge($parents, array('floors', $f, 'rows', $r)),
        'columns' => array(
          '#tree' => TRUE,
          '#parents' => array_merge($parents, array('floors', $f, 'rows', $r, 'columns')),
        )
      );
      foreach ($row['columns'] as $c => $column) {
        //add the seat string and value
        $element['floors'][$f]['rows'][$r]['columns'][$c]['drag'] = array(
          '#parents' => array_merge($parents, array('floors', $f, 'rows', $r, 'columns', $c, 'drag')),
          '#attributes' => array('class' => 'allocated-seating-seat'),
          '#type' => '#markup',
          '#value' => $column['seat'] ? $column['seat'] : '&nbsp;'
        );
        $element['floors'][$f]['rows'][$r]['columns'][$c]['seat'] = array(
          '#parents' => array_merge($parents, array('floors', $f, 'rows', $r, 'columns', $c, 'seat')),
          '#type' => 'hidden',
          '#value' => $column['seat']
        );
      }
    }
  }

  $element['add_floor_row_count'] = array(
    '#type'          => 'textfield',
    '#title'         => t('Rows'),
    '#default_value' => isset($form_state['post']['add_floor_row_count']) ? $form_state['post']['add_floor_row_count'] : 4,
    '#size'          => 10,
    '#maxlength'     => 10
  );

  $element['add_floor_col_count'] = array(
    '#type'          => 'textfield',
    '#title'         => t('Cols'),
    '#default_value' => isset($form_state['post']['add_floor_col_count']) ? $form_state['post']['add_floor_col_count'] : 10,
    '#size'          => 10,
    '#maxlength'     => 10
  );

  $element['add_floor_ticket_count'] = array(
    '#type'          => 'textfield',
    '#title'         => t('Tickets'),
    '#default_value' => 0,
    '#size'          => 10,
    '#maxlength'     => 10,
    '#description'   => t('Start with this many tickets on the floor')
  );

  $element['add_floor'] = array(
    '#type' => 'submit',
    '#value' => t('Add floor'),
    '#submit' => array('allocated_seating_design_add_floor'),
    '#executes_submit_callback' => true,
    '#ajax' => array(
      'path' => 'allocated_seating/ajax/floor/'. $element['#ajax_extra'] . implode('/', $parents),
      'callback' => 'allocated_seating_design_add_floor',
      'wrapper' => 'as-wrap-'. $element['#id'],
      'method' => 'replace',
      'effect' => 'fade',
    )
  );
  return $element;
}

/**
 * Removes a floor from the design
*/
function allocated_seating_design_remove_floor($form, &$form_state) {
  $button = $form_state['clicked_button'];
  $field_parents = $button['#parents'];
  $floor = $field_parents[count($field_parents) - 2];
  $depth = count($field_parents) - 4;
  $field_name = $field_parents[$depth];
  if ($depth > 0) {
    //we have a tree arrangement here
    switch ($depth) {
      case 1:
        allocated_seating_plan_remove_floor($form_state['values'][$field_parents[0]][$field_name], $floor);
        break;
      case 2:
        allocated_seating_plan_remove_floor($form_state['values'][$field_parents[0]][$field_parents[1]][$field_name], $floor);
        break;
      case 3:
        allocated_seating_plan_remove_floor($form_state['values'][$field_parents[0]][$field_parents[1]][$field_parents[2]][$field_name], $floor);
        break;
      //that ought to be enough
    }
  }
  else {
    allocated_seating_plan_remove_floor($form_state['values'][$field_name], $floor);
  }
  unset($form_state['submit_handlers']);
  form_execute_handlers('submit', $form, $form_state);
  $form_state['rebuild'] = TRUE;
}

/**
 * Adds a floor to a design
*/
function allocated_seating_design_add_floor($form, &$form_state) {

  $button = $form_state['clicked_button'];
  $parents = $button['#array_parents'];
  $button_name = array_pop($parents);
  $field_name = array_pop($parents);
  $field_parents = $button['#parents'];
  $new_rows = $form_state['values']['add_floor_row_count'];
  $new_cols = $form_state['values']['add_floor_col_count'];
  $new_tickets = $form_state['values']['add_floor_ticket_count'];

  if (count($field_parents) > 1) {
    //we have a tree arrangement here
    switch (count($field_parents)) {
      case 2:
        //allocated_seating_plan_add_floor($form_state['values'][$field_parents[0]][$field_name], $new_rows, $new_cols, $new_tickets);
        break;
      case 3:
       // allocated_seating_plan_add_floor($form_state['values'][$field_parents[0]][$field_parents[1]][$field_name], $new_rows, $new_cols, $new_tickets);
        break;
      case 4:
       // allocated_seating_plan_add_floor($form_state['values'][$field_parents[0]][$field_parents[1]][$field_parents[2]][$field_name], $new_rows, $new_cols, $new_tickets);
        break;
      //that ought to be enough
    }
  }
  else {
    //allocated_seating_plan_add_floor($form_state['values'][$field_name], $new_rows, $new_cols, $new_tickets);
  }
  unset($form_state['submit_handlers']);
  form_execute_handlers('submit', $form, $form_state);
  $form_state['rebuild'] = TRUE;
}

/**
 * Default implementation of theme_allocated_seating_seat_select
*/
function theme_allocated_seating_seat_select($element) {
  jquery_ui_add(array('ui.sortable', 'ui.droppable', 'ui.tabs'));
  drupal_add_js(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.js');
  drupal_add_css(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.css');
  drupal_add_css(drupal_get_path('module', 'jquery_ui') . '/jquery.ui/themes/default/ui.all.css');
  $output = '<div id="allocated-seating-tabs" class="allocated-seating-seat-select"><ul>';
  $tabs = '';
  foreach (element_children($element['floors']) as $key) {
    $title = $element['floors'][$key]['title']['#value'];
    $output .= '<li><a href="#allocated-seating-tabs-'. $key .'">'. check_plain($title) .'</a></li>';
    $tabs .= '<div id="allocated-seating-tabs-'. $key .'">'.
      $element['floors'][$key]['title']['#value']
      . '<div class="floor-front cols-'. $element['floors'][$key]['#col_count'] .'">'. t('Front') .'</div>'
      .'<ul class="allocated-seating-seats no-drag cols-'. $element['floors'][$key]['#col_count'] .'">';
    foreach (element_children($element['floors'][$key]['rows']) as $row) {
      foreach (element_children($element['floors'][$key]['rows'][$row]['columns']) as $column) {
        $tabs .= '<li class="ui-state-highlight';
        if ($element['floors'][$key]['rows'][$row]['columns'][$column]['#type'] == 'checkbox') {
          $tabs .= '">'. theme('checkbox', $element['floors'][$key]['rows'][$row]['columns'][$column]);
        }
        else {
          $tabs .= ' not-available">&nbsp';
        }
        $tabs .=  '</li>';
      }
    }
    $tabs .= '</ul>'. $values .'<div class="clear"></div></div>';
  }
  $output .= '</ul>';
  $output .= $tabs;
  $output .= '</div>';
  return $output;
}

/**
 * Default implementation of theme_allocated_seating_seat_available
*/
function theme_allocated_seating_seat_available($plan, $not_available) {
  $blank = 1;
  $element['floors'] = array(
    '#tree' => FALSE, //we structure the data in a nest for theming but only want seat# => 1/0
    '#parents' => array('floors')
  );
  foreach ($plan['floors'] as $f => $floor) {
    $element['floors'][$f] = array(
      '#tree' => FALSE,
      '#col_count' => $floor['col_count'],
      'title' => array(
        '#value' => $floor['title']
      ),
      'rows' => array(
        '#tree' => FALSE,
      )
    );
    foreach ($floor['rows'] as $r => $row) {
      $element['floors'][$f]['rows'][$r] = array(
        '#tree' => FALSE,
        'columns' => array(
          '#tree' => FALSE,
          '#parents' => array('floors', $f, 'rows', $r, 'columns'),
        )
      );
      foreach ($row['columns'] as $c => $column) {
        $state = 'available';
        if ($column['seat'] &&
            is_numeric($column['seat']) &&
            in_array($column['seat'], $not_available)) {
          $state = 'unavailable';
        }
        //add the seat field
        $element['floors'][$f]['rows'][$r]['columns'][$column['seat']] = array(
          '#value' => '<div class="allocated-seating-seat '. $state .'">'. $column['seat'] .'</div>',
          '#parents' => array('seats', $column['seat']),
        );
      }
    }
  }
  drupal_add_library('system', 'ui.sortable');
  drupal_add_library('system', 'ui.tabs');
  drupal_add_library('system', 'ui.droppable');
  //jquery_ui_add(array('ui.sortable', 'ui.droppable', 'ui.tabs'));
  drupal_add_js(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.js');
  drupal_add_css(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.css');
  drupal_add_css(drupal_get_path('module', 'jquery_ui') . '/jquery.ui/themes/default/ui.all.css');
  $output = '<div id="allocated-seating-tabs" class="allocated-seating-seat-select"><ul>';
  $tabs = '';
  foreach (element_children($element['floors']) as $key) {
    $title = $element['floors'][$key]['title']['#value'];
    $output .= '<li><a href="#allocated-seating-tabs-'. $key .'">'. check_plain($title) .'</a></li>';
    $tabs .= '<div id="allocated-seating-tabs-'. $key .'">'.
      $element['floors'][$key]['title']['#value']
      . '<div class="floor-front cols-'. $element['floors'][$key]['#col_count'] .'">'. t('Front') .'</div>'
      .'<ul class="allocated-seating-seats no-drag cols-'. $element['floors'][$key]['#col_count'] .'">';
    foreach (element_children($element['floors'][$key]['rows']) as $row) {
      foreach (element_children($element['floors'][$key]['rows'][$row]['columns']) as $column) {
        $tabs .= '<li class="ui-state-highlight">'.
          drupal_render($element['floors'][$key]['rows'][$row]['columns'][$column])
        .'</li>';
      }
    }
    $tabs .= '</ul>'. $values .'<div class="clear"></div></div>';
  }
  $output .= '</ul>';
  $output .= $tabs;
  $output .= '</div>';
  return $output;
}

/**
 * Default implementation of theme_allocated_seating_seat_design
*/
function theme_allocated_seating_seat_design($variable) {
  drupal_add_library('system', 'ui.sortable');
  drupal_add_library('system', 'ui.tabs');
  drupal_add_library('system', 'ui.droppable');
  $element = array_shift($variable);

  //jquery_ui_add(array('ui.sortable', 'ui.tabs', 'ui.droppable'));
  drupal_add_js(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.js');
  drupal_add_css(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.css');
  drupal_add_css(drupal_get_path('module', 'jquery_ui') . '/jquery.ui/themes/default/ui.all.css');
  $output = '<div id="as-wrap-'. $element['#id'] .'" class="as-wrap"><div id="allocated-seating-tabs" class="allocated-seating-seat-design"><ul>';
  $tabs = '';
  foreach (element_children($element['floors']) as $key) {
    $inputs = '';
    $title = $element['floors'][$key]['title']['#value'];
    $output .= '<li><a href="#allocated-seating-tabs-'. $key .'">'. check_plain($title) .'</a></li>';
    $tabs .= '<div id="allocated-seating-tabs-'. $key .'" class="floor-details">'.
      '<div class="floor-item">'.
      theme('form_element_label', $element['floors'][$key]['title']).
      theme('textfield', $element['floors'][$key]['title']) .
      '</div><div class="floor-item">'.
      theme('form_element_label', $element['floors'][$key]['row_count']).
      theme('textfield', $element['floors'][$key]['row_count']) .
      '</div><div class="floor-item">'.
      theme('form_element_label', $element['floors'][$key]['col_count']).
      theme('textfield', $element['floors'][$key]['col_count']).
      '</div>'
      . '<div class="floor-front cols-'. $element['floors'][$key]['col_count']['#value'] .'">'. t('Front') .'</div>'
      .'<ul class="allocated-seating-seats connectedSortable ui-helper-reset cols-'. $element['floors'][$key]['col_count']['#value'] .'">';
    foreach (element_children($element['floors'][$key]['rows']) as $row) {
      foreach (element_children($element['floors'][$key]['rows'][$row]['columns']) as $column) {
        $tabs .= '<li class="ui-state-highlight" rel="'. $element['floors'][$key]['rows'][$row]['columns'][$column]['seat']['#value'] .'">'.
                    $element['floors'][$key]['rows'][$row]['columns'][$column]['drag']['#value']
                .'</li>';
        $inputs .= theme('hidden', $element['floors'][$key]['rows'][$row]['columns'][$column]['seat']);
      }
    }
    $tabs .= $inputs .'</ul>'. $values .'<div class="clear"></div>'.
      drupal_render($element['floors'][$key]['remove_floor'])
      .'</div>';
  }
  $output .= '</ul>';
  $output .= $tabs;
  $output .= '</div><div class="allocated-seating-design-add-floor"><fieldset><legend>'. t('Add a floor') .'</legend>'.
            t('Add a new floor with this many rows/columns').
            drupal_render($element['add_floor_row_count']).
            drupal_render($element['add_floor_col_count']).
            drupal_render($element['add_floor_ticket_count']).
            drupal_render($element['add_floor'])
          .'</fieldset></div>';
  if (!empty($element['#description'])) {
    $output .= ' <div class="description as-description">'. $element['#description'] ."</div>\n";
  }
  $output .= '</div><div class="clear"></div>';
  return $output;
}

/**
 * Validation handler for seat selection
*/
function allocated_seating_seat_select_validate($element, &$form_state) {
  $seats = array_sum($form_state['values']['seats']);
  if ($element['#required_seats'] &&
      $element['#required_seats'] != $seats) {
    form_error($element, format_plural($element['#required_seats'],
                                     'Please choose 1 seat',
                                     'Please choose @count seats'));
  }
}

/**
 * Call callback handler.
 *
 */
function allocated_seating_ajax() {
  module_load_include('inc', 'node', 'node.pages');
  //get args

  $elements = func_get_args();
  $type = array_shift($elements);
  if ($type == 'row' || $type == 'column') {
    $floor = array_shift($elements);
  }


  //we set submitted as TRUE so prevent _form_builder_ie_cleanup() from triggering
  //submit on ajax that does not involve a button
  $form_state = array('storage' => NULL, 'submitted' => TRUE);
  $form_build_id = $_POST['form_build_id'];
  $form = form_get_cache($form_build_id, $form_state);
  if (isset($_POST['_triggering_element_name'])) {

    if($_POST['_triggering_element_name'] == 'op' && $_POST['_triggering_element_value'] == 'Add floor') {
        $form_state['submit_handlers'] = array('allocated_seating_design_add_floor');
    }
  }

  unset($form_state['storage']['type']); //don't redo the cached action
  //remove validation (thanks ajax_helper!)
  if (!isset($_POST['op'])) {
    // For the defaults
    $form['#validate'] = NULL;
    $form['#submit'] = NULL;
    // For customly set #validate and #submit handlers.
    $form_state['submit_handlers'] = array();
    $form_state['validate_handlers'] = array();
  }
  $form_id = $form['#form_id'];
  $form['#post'] = $_POST;
  $form['#redirect'] = FALSE;
  $form['#programmed'] = FALSE;
  $form_state['post'] = $_POST;

  drupal_process_form($form_id, $form, $form_state);

  $form_state['storage']['type'] = $type;
  $form_state['storage']['floor'] = $floor;
  if ($type == 'floor') {
    $form_state['storage']['add_floor_row_count'] = $form_state['values']['add_floor_row_count'];
    $form_state['storage']['add_floor_col_count'] = $form_state['values']['add_floor_col_count'];
  }

  $form = drupal_rebuild_form($form_id, $form_state,  $form );
  foreach ($elements as $element) {
    $form = $form[$element];
  }
  if (!$form) {
    watchdog('allocated seating', 'Call method was called with elements not found in resultant form', array(), WATCHDOG_ERROR);
    $form = array(
      'error' => array(
        '#value' => t('An error occured while processing your request, please try again. If the problem persists, please contact the site administrator')
      )
    );
  }
  unset($form['#prefix'], $form['#suffix']); // Prevent duplicate wrappers.
  $javascript = drupal_add_js(NULL, NULL, 'header');
  // Loop through the JS settings and find the settings needed for our buttons.


  $new_ajax_settings = array();
  if (isset($javascript['settings'])) {
    foreach ($javascript['settings'] as $settings) {
      if (isset($settings['ajax'])) {
        foreach ($settings['ajax'] as $id => $ajax_settings) {
            $new_ajax_settings[$id] = $ajax_settings;
        }
      }
    }
  }

  // Add the Call settings needed for our new elements.
  if (!empty($new_ajax_settings)) {
    $output = '<script type="text/javascript">jQuery.extend(Drupal.settings.Ajax, '. drupal_to_js($new_ajax_settings) .');</script>';
  }

  return array(array(
    'status'   => TRUE,
    'data'     => theme('status_messages') . $output . drupal_render($form),
    'settings' => call_user_func_array('array_merge_recursive', $javascript['setting']),
    'command' => 'syncSeating'
  ));
}

/**
 * Utility to remove a floor from the plan
 * @param $plan array the plan
*/
function allocated_seating_plan_remove_floor(&$plan, $floor) {
  if (!isset($plan['floors'][$floor])) {
    return;
  }
  foreach ($plan['floors'][$floor]['rows'] as $row) {
    foreach ($row['columns'] as $col) {
      if ((int)$col['seat'] > 0) {
        form_set_error('', t('You cannot remove this floor, it still contains seats, please move them to another floor first.'));
        return;
      }
    }
  }
  unset($plan['floors'][$floor]);
}


/**
 * Utility to remove a col from the plan
 * @param $plan array the plan
*/
function allocated_seating_plan_remove_column(&$plan, $floor) {
  if (!isset($plan['floors'][$floor])) {
    return;
  }
  $remove_col = count($plan['floors'][$floor]['rows'][0]['columns']) - 1;
  foreach ($plan['floors'][$floor]['rows'] as $row) {
    $col = $row['columns'][$remove_col];
    if ((int)$col['seat'] > 0) {
      form_set_error('', t('You cannot remove the last column from this floor, it still contains seats, please move them to another floor or column first.'));
      return;
    }
  }
  foreach ($plan['floors'][$floor]['rows'] as $key => $row) {
    unset($plan['floors'][$floor]['rows'][$key]['columns'][$remove_col]);
  }
}

/**
 * Utility to remove a row from the plan
 * @param $plan array the plan
*/
function allocated_seating_plan_remove_row(&$plan, $floor) {
  if (!isset($plan['floors'][$floor])) {
    return;
  }
  $remove_row = count($plan['floors'][$floor]['rows']) - 1;
  foreach ($plan['floors'][$floor]['rows'][$remove_row]['columns'] as $col) {
    if ((int)$col['seat'] > 0) {
      form_set_error('', t('You cannot remove the last row from this floor, it still contains seats, please move them to another floor or row first.'));
      return;
    }
  }
  unset($plan['floors'][$floor]['rows'][$remove_row]);
}

/**
 * Utility to add a floor to a plan
 * @param $plan array the plan
*/
function allocated_seating_plan_add_floor(&$element, &$post) {

  $plan = &$element['#value'];
  $rows = $plan['add_floor_row_count'];
  $cols = $plan['add_floor_col_count'];
  $tickets = $plan['add_floor_ticket_count'];
  $available_tickets = array();
  if ($tickets) {
    if ($tickets > ($rows * $cols)) {
      $tickets = $rows * $cols;
      drupal_set_message(t('You cannot move more than !tix seats to the new floor', array('!tix' => ($rows * $cols))));
    }
    $map = allocated_seating_get_map($plan);
    $seat = count($available_tickets);
    $seats = $map['seats'];
    $seat_numbers = array_keys($seats);
    asort($seat_numbers);
    while ($seat < $tickets) {
      $seat++;
      $new_seat = array_pop($seat_numbers);
      $remove = $seats[$new_seat];
      $available_tickets[] = $new_seat;
      $plan['floors'][$remove['floor']]['rows'][$remove['row']]['columns'][$remove['column']]['seat'] = FALSE;
    }
  }
  $floor = array(
    'title' => t('Floor !floor', array('!floor' => count($plan['floors']) + 1)),
    'rows' => array()
  );
  $row = 0;
  $s = 1;
  while ($row < $rows) {
    $col = 0;
    $floor['rows'][$row] = array('columns' => array()); //add the rows
    while ($col < $cols) {
      if (count($available_tickets) > 0) {
        $seat = array_pop($available_tickets);
      }
      else {
        $seat = FALSE;
      }
      $floor['rows'][$row]['columns'][] = array('seat' => $seat); //add the seat as a blank or a number
      $col++;
    }
    $row++;
  }
  $plan['floors'][] = $floor;
}

/**
 * Utility to add row to a floor of a plan
 * @param $plan array the plan
 * @param $floor int the floor delta
*/
function allocated_seating_plan_floor_add_row(&$plan, $floor) {
  $cols = count($plan['floors'][$floor]['rows'][0]['columns']);
  $rows = count($plan['floors'][$floor]['rows']);
  $col = 0;
  $row = array('columns' => array()); //create the row
  while ($col < $cols) {
    $row['columns'][] = array('seat' => FALSE); //add the seat as a blank
    $col++;
  }
  $plan['floors'][$floor]['rows'][] = $row;
}

/**
 * Utility to add column to a floor of a plan
 * @param $plan array the plan
 * @param $floor int the floor delta
*/
function allocated_seating_plan_floor_add_column(&$plan, $floor) {
  $rows = count($plan['floors'][$floor]['rows']);
  $row = 0;
  while ($row < $rows) {
    $plan['floors'][$floor]['rows'][$row]['columns'][] = array('seat' => FALSE);
    $row++;
  }
}

/**
 * Utility to setup required js files etc
*/
function allocated_seating_setup() {
  drupal_add_library('system', 'ui.sortable');
  drupal_add_library('system', 'ui.tabs');
  drupal_add_library('system', 'ui.droppable');
  //jquery_ui_add(array('ui.sortable', 'ui.tabs', 'ui.droppable'));
  drupal_add_js(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.js');
  drupal_add_css(drupal_get_path('module', 'allocated_seating') .'/allocated_seating.css');
}

/**
 * Util to fetch number of rows and columns (seats) submitted in the plan
 * @param $plan array seating plan as submitted in $element['#value']
*/
function allocated_seating_total_seats($plan) {
  $seats = 0;
  foreach ($plan['floors'] as $floor) {
    $rows = $floor['row_count'];
    $cols = $floor['col_count'];
    $seats += ($rows * $cols);
  }
  return $seats;
}

/**
 * Util to fetch number of rows and columns (seats) submitted in the plan
 * @param $plan array seating plan as submitted in $element['#value']
*/
function allocated_seating_plan_seats($plan) {
  $seats = 0;
  foreach ($plan['floors'] as $floor) {
    $rows = count($floor['rows']);
    $cols = count($floor['rows'][0]['columns']);
    $seats += ($rows * $cols);
  }
  return $seats;
}

/**
 * Util to fetch number of real seats (non blank) in the plan
 * @param $plan array seating plan as submitted in $element['#value']
*/
function allocated_seating_real_seats($plan) {
  $seats = 0;
  foreach ($plan['floors'] as $floor) {
    foreach ($floor['rows'] as $row) {
      foreach ($row['columns'] as $column) {
        if ((int)$column['seat'] > 0) {
          $seats++;
        }
      }
    }
  }
  return $seats;
}

/**
 * Util to fetch reveresed map keyed by seat
 * @param $plan array seating plan
 * @return array with two members as follows
 *  seats => array keyed by seat # with array or floor, row and column members
 *  blanks => same but for blanks
*/
function allocated_seating_get_map($plan) {
  $map = $blanks = array();
  foreach ($plan['floors'] as $fid => $floor) {
    foreach ($floor['rows'] as $rid => $row) {
      foreach ($row['columns'] as $cid => $column) {
        if ((int)$column['seat'] > 0) {
          $map[$column['seat']] = array('row' => $rid, 'column' => $cid, 'floor' => $fid);
        }
        else {
          $blanks[] = array('row' => $rid, 'column' => $cid, 'floor' => $fid);
        }
      }
    }
  }
  return array('seats' => $map, 'blanks' => $blanks);
}