<?php
// $Id: calendar.module,v 1.20.2.75 2007-07-04 16:43:46 karens Exp $

/**
 * @file
 * Adds calendar display themes to views.
 */

/**
 * Implementation of hook_init().
 */
function calendar_init() {
  // ensure we are not serving a cached page
  if (function_exists('drupal_set_content')) {
    // TODO this can be removed later. Added to ease transition to new schema that requires Date API.
    // Needed because non-existant functions will cause fatal error that prevents ability to get back
    // to module installation page.
    if (!module_exists('date_api')) {
      module_disable(array('calendar'));
      module_disable(array('calendar_ical'));
      drupal_set_message(t('Date API module is not installed. Calendar module was disabled.'));
    }
  }
}

/**
 * Implementation of hook_help().
 */
function calendar_help($section) {
  switch ($section) {
    case 'admin/help#calendar':
      return t("<p>View complete documentation at !link.</p>", array('!link' => 'http://drupal.org/node/120710'));
  }
}

/**
 *  Implementation of hook_menu().
 */
function calendar_menu($may_cache) {

  include_once(drupal_get_path('module', 'calendar') .'/calendar.theme');
  drupal_add_css(drupal_get_path('module', 'calendar') .'/calendar.css');
  define('CALENDAR_EMPTY_ARG', variable_get('calendar_empty_arg', 'all'));

  $items = array();
  if (!$may_cache) {
    foreach (calendar_views('page') as $view_name) {
      $items[] = array(
        'path'     => $view_name['url'] .'/setup',
        'title'    => t('Setup'),
        'description' => t('Calendar setup.'),
        'access'   => user_access('administer views'),
        'callback' => 'drupal_get_form',
        'callback arguments' => array('calendar_setup_form', $view_name['name']),
        'type' => MENU_LOCAL_TASK,
        'weight' => 5,
      );
    }
  }
  return $items;
}

/**
 * Implementation of hook_views_tabs().
 */
function calendar_views_tabs($op) {
  switch ($op) {
    case 'names':
      return array('setup');
  }
}

/**
 * Helper function for loading date_api.
 */
function calendar_load_date_api() {
  include_once(drupal_get_path('module', 'date_api') .'/date.inc');
}

/**
 * Helper function for loading calendar_api.
 */
function calendar_load_calendar_api() {
	include_once(drupal_get_path('module', 'calendar') .'/calendar_api.inc');
}

/**
 *  Implementation of hook_views_style_plugins()
 */
function calendar_views_style_plugins() {
  $plugins = array();
  $types = array('calendar' => t('Calendar'));
  foreach ($types as $name => $type) {
    $plugins[$name] = array(
      'name' => $type,
      'theme' => 'calendar_display',
      'summary_theme' => 'calendar_display',
      'validate' => 'calendar_views_validate',
      'needs_fields' => TRUE,
      'needs_table_header' => FALSE,
      );
  }
  return $plugins;
}

/**
 * Validate a view.
 */
function calendar_views_validate($type, $view, $form) {
  // list (and table) modes require there to be at least 1 field active.
  if (is_array($view['field'])) {
    $fields = array_filter(array_keys($view['field']), 'is_numeric');
  }
  if (!$fields) {
    form_error($form["$type-info"][$type . '_type'], t('The Calendar View requires at least one field.'));
  }

  if (isset($view['field']['count'])) {
    $defaultsort = false;
    for ($i = 0; $i < $view['field']['count']; $i++) {
      if ($view['field'][$i]['defaultsort']) {
        if ($defaultsort) {
          form_error($form['field'][$i]['defaultsort'], t('You can only set on Default Sort on one field.'));
          break;
        }
        $defaultsort = true;
      }
    }
  }
  // Make sure all arguments are set to 'Display all values'.
  $arg_types = array();
  $cal_args = array('calendar_year', 'calendar_month', 'calendar_day', 'calendar_week');
  foreach ($view['argument'] as $delta => $argument) {
    if (in_array($argument['type'], $cal_args)) {
      $view['argument'][$delta]['argdefault'] = 2;
      if ($argument['argdefault'] != 2) {
        form_error($form['argument'][$delta]['argdefault'], t('Calendar arguments must be set to \'Display All Values\'.'));
      }
      $arg_types[] = $argument['type'];
    }
  }
  // Must have Year, Month, and Day or Year and Week calendar arguments.
  if (!in_array('calendar_year', $arg_types) && ((!in_array('calendar_month', $arg_types) && !in_array('calendar_day', $arg_types) || !in_array('calendar_week', $arg_types)))) {
    form_error($form['argument'], t('The Calendar requres as arguments Calendar: Year, Calendar: Month, and Calendar: Day, or Calendar: Year and Calendar: Week'));
  }
  // CCK date fields cannot use grouped handler.
  $calendar_fields = array_keys(calendar_fields());
  foreach ($view['field'] as $delta => $field) {
    if (in_array($field['field'], $calendar_fields) && $field['handler'] == 'content_views_field_handler_group') {
      form_error($form['field'][$delta]['handler'], t('Calendar CCK Date fields must be set to \'Do not group multiple values\'.'));
    }
  }
}

/**
 *  Function to return all possible calendar views page display types.
 *  Implements hook_calendar_add_types($view) for other modules to add calendar types.
 */
function calendar_view_types($reset = FALSE) {
  static $types;
  if ($reset || !isset($types)) {
  	$types = array('calendar' => t('Calendar'));
    foreach (module_implements('calendar_add_items') as $module) {
      $function = $module .'_calendar_add_types';
      $types += $function($view);
    }
  }
  return $types;
}

/**
 * Function to return all views that are of the type 'calendar'.
 */
function calendar_views($build_type = 'page', $reset = FALSE) {
  static $calendar_views;
  views_load_cache();
  if (empty($calendar_views)) {
  	$calendar_views = array($build_type => '');
  }
  if ($reset || empty($calendar_views[$build_type])) {
    $calendar_views = array();
    $result = db_query("SELECT vid, name, url FROM {view_view} ORDER BY name");
    while ($view = db_fetch_object($result)) {
      $view->build_type = $build_type;
      if (calendar_is_calendar($view)) {
        $calendar_views[$build_type][] = array('name' => $view->name, 'url' => $view->url);
      }
    }
    $check = $build_type .'_type';
    foreach (_views_get_default_views() as $view) {
      if ($view->$check == 'calendar' && empty($view->disabled)) {
        $calendar_views[$build_type][] = array('name' => $view->name, 'url' => $view->url);
      }
    }
  }
  if (empty($calendar_views) || !array_key_exists($build_type, $calendar_views)) {
    $calendar_views = array($build_type => array());
  }
  return $calendar_views[$build_type];
}

/**
 *  Function to test whether this is a view that uses the calendar plugin theme.
 */
function calendar_is_calendar($view, $reset = FALSE) {
  static $is_calendar;
  if (empty($is_calendar)) {
  	$is_calendar = array($view->name => array($view->build_type => FALSE));
  }
  if ($reset || empty($is_calendar[$view->name][$view->build_type])) {
  	$is_calendar = FALSE;
    if ($view->build_type == 'page' && !array_key_exists($view->page_type, calendar_view_types())) {
    	$is_calendar[$view->name][$view->build_type] = FALSE;
    }
    elseif ($view->build_type == 'page' && calendar_has_calendar_args($view)) {
    	$is_calendar[$view->name][$view->build_type] = TRUE;
    }
    if ($view->build_type == 'block' && !array_key_exists($view->block_type, calendar_view_types())) {
    	$is_calendar[$view->name][$view->build_type] = FALSE;
    }
    elseif ($view->build_type == 'block' && calendar_has_calendar_args($view)) {
    	$is_calendar[$view->name][$view->build_type] = TRUE;
    }
  }
  return $is_calendar[$view->name][$view->build_type];
}

/**
 * Function to test whether any calendar args are used in this view.
 */
function calendar_has_calendar_args($view, $reset = FALSE) {
	static $has_args;
	if (empty($has_args)) {
		$has_args = array($view->name => FALSE);
	}
	if ($reset || empty($has_args[$view->name])) {
		foreach ($view->argument as $delta => $argument) {
      if (in_array($argument['type'], array('calendar_year', 'calendar_month', 'calendar_day', 'calendar_week'))) {
        $has_args[$view->name] = TRUE;
      }
    }
  }
  return $has_args[$view->name];
}

/**
 * Identify the final calendar argument in this view.
 *   Needed because we can't construct a query until we know all the calendar elements.
 *   Used to tell when to add the filter to the query object.
 *
 * @param object $view
 * @return string $argtype
 */
function calendar_last_argtype($view, $reset = FALSE) {
	static $argtype;
	if (empty($argtype)) {
		$argtype = array($view->name => '');
	}
	if ($reset || empty($argtype[$view->name])) {
		$calendar_args[] = array();
		foreach ($view->argument as $argument) {
      if (in_array($argument['id'], array('calendar_year', 'calendar_month', 'calendar_week', 'calendar_day'))) {
        $calendar_args[] = $argument['id'];
      }
    }
    $argtype[$view->name] = array_pop($calendar_args);
  }
  return $argtype[$view->name];
}

/**
 *  Identify all potential date/timestamp fields
 *  @return an array with fieldname, type, and table
 *  TODO add caching
 */
function calendar_fields($reset = FALSE) {
	static $fields;
	if ($reset || empty($fields)) {
    // iterate through all the views fields
    $delta = 0;
    foreach (_views_get_fields() as $name => $val) {
      $timestamp_fromto = array();
      $string_fromto = array();
      $type = '';
      // for cck fields, get the date type
      if ($val['content_field']['type'] == 'date' || $val['content_field']['type'] == 'datestamp') {
        $type = $val['content_field']['type'] == 'date' ? 'cck_string' : 'cck_timestamp';
      }
      // all other fields that use the views date handler are timestamps
      elseif ($val['handler'] == views_handler_field_dates()) {
        $type = 'timestamp';
      }
      // don't do anything if this is not a date field
      if ($type) {
        // dates with from and to dates need to handle both fields as one
        // add the from and to dates to the first one found and ignore the second
        // Handling for event fromto dates
        if (module_exists('event') && !$event_field_processed && ($name == 'event.event_start' || $name == 'event.event_end')) {
          $timestamp_fromto = array('event.event_start', 'event.event_end');
          $offset_field = 'event.timezone';
          $tz_handling = variable_get('event_timezone_display', 'site');
          $event_field_processed = TRUE;
        }
        elseif ($val['content_field']['tz_handling']) {
          $tz_handling = $val['content_field']['tz_handling'];
          if ($tz_handling == 'date') $offset_field = $val['table'] .'.'. $val['content_db_info']['columns']['offset']['column'];
        }
        else {
          $tz_handling = 'site';
        }
        // Handling for cck fromto dates
        if (!$event_field_processed && $val['content_field']['todate']) {
          switch ($val['content_field']['type']) {
          case 'datestamp':
            $timestamp_fromto = array($val['table'] .'.'. $val['content_field']['field_name'] .'_value', $val['table'] .'.'. $val['content_field']['field_name'] .'_value2');
            break;
          case 'date':
            $string_fromto = array($val['table'] .'.'. $val['content_field']['field_name'] .'_value', $val['table'] .'.'. $val['content_field']['field_name'] .'_value2');
            break;
          }
          $event_field_processed == TRUE;
        }
        // skip this step on second occurance of fromto date fields, if more than one exists in view
        if (!$event_field_processed || $timestamp_fromto || $string_fromto) {
          // cck fields append a column name to the field, others do not
          // need a real field_name with no column name appended for cck date formatters
          $tmp = explode('.', $name);
          $field_name = $val['content_field']['field_name'] ? $val['content_field']['field_name'] : $tmp[1];
          $fields[$tmp[1]] = array(
            'type' => $type,
            'delta' => $delta,
            'label' => $val['name'],
            'granularity' => is_array($val['content_field']['granularity']) ? (array) array_keys($val['content_field']['granularity']) : array('Y', 'M', 'D', 'H', 'N'),
            'fullname' => $name,
            'table' => $tmp[0],
            'field' => $tmp[1],
            'field_name' => $field_name,
            'query_name' => str_replace('.', '_', $name),
            'timestamp_fromto' => $timestamp_fromto,
            'string_fromto' => $string_fromto,
            'tz_handling' => $tz_handling,
            'offset_field' => $offset_field,
          );
        }
      }
    }
  }

  return $fields;
}

/**
 *  Calendar Views plugin theme, overrides default views theme
 */
function theme_calendar_display(&$view, &$items, $type) {

  if ($type == 'block') {
    $view->calendar_type = 'month';
  }
  $mini = $view->calendar_type == 'year' || $view->build_type == 'block' ? TRUE : FALSE;
  $links = $view->build_type == 'block' ? FALSE : TRUE;

  // Bail out here to display regular views views instead of calendar.
  // Check first for 'view' in url, then for 'calendar_display_format' variable, default to normal calendar display.
  if ($_GET['view'] && $view->build_type == 'page') {
  	$display = check_plain($_GET['view']);
  }
  else {
  	$display_formats = variable_get('calendar_display_format_'. $view->name, array('year' => 'calendar', 'month' => 'calendar', 'week' => 'calendar', 'day' => 'calendar', 'block' => 'calendar'));
  	$display = $view->build_type == 'block' ? $display_formats['block'] : $display_formats[$view->calendar_type];
  }
  switch($display) {
    case ('table') :
      $view->table_header = _views_construct_header($view, _views_get_fields());
      return theme('calendar_show_nav', $view, $mini, $links) . theme('calendar_view_table', $view, $items, $type);
    case ('teasers') :
      return theme('calendar_show_nav', $view, $mini, $links) . theme('calendar_view_teasers', $view, $items, $type);
    case ('nodes') :
      return theme('calendar_show_nav', $view, $mini, $links) . theme('calendar_view_nodes', $view, $items, $type);
    case ('list') :
      return theme('calendar_show_nav', $view, $mini, $links) . theme('calendar_view_list', $view, $items, $type);
  }
  $results = calendar_get_nodes($view, $items, $type);
  $nodes = (array) $results['nodes'];
  $params = (array) $results['params'];
  // Weeks still aren't working right in all situations, turning them off for now.
  $params[with_weekno] = FALSE;
  $nodes += calendar_add_items($view, 'calendar');
  return theme('calendar_show_nav', $view, $mini, $links) . calendar_get_calendar($view->calendar_type, $nodes, 'calendar', '', $params);
}

/**
 * Display the nodes of a view as a list.
 */
function theme_calendar_view_list($view, $nodes, $type) {
  $fields = _views_get_fields();
  $items = array();
  foreach ($nodes as $node) {
    $item = '';
    foreach ($view->field as $field) {
      if ($fields[$field['id']]['visible'] !== FALSE) {
        if ($field['label']) {
          $item .= "<div class='view-label ". views_css_safe('view-label-'. $field['queryname']) ."'>" . $field['label'] . "</div>";
        }
        $item .= "<div class='view-field ". views_css_safe('view-data-'. $field['queryname']) ."'>" . views_theme_field('views_handle_field', $field['queryname'], $fields, $field, $node, $view) . "</div>";
      }
    }
    $items[] = "<div class='view-item ". views_css_safe('view-item-'. $view->name) ."'>$item</div>\n"; // l($node->title, "node/$node->nid");
  }
  $items += calendar_add_items($view, 'list');
  if ($items) {
   	return theme('item_list', $items);
  }
}

/**
 * Display the nodes of a view as a table.
 */
function theme_calendar_view_table($view, $nodes, $type) {
  $fields = _views_get_fields();
  $rows = array();
  foreach ($nodes as $node) {
    $row = array();
    foreach ($view->field as $field) {
      if ($fields[$field['id']]['visible'] !== FALSE) {
        $cell['data'] = views_theme_field('views_handle_field', $field['queryname'], $fields, $field, $node, $view);
        $cell['class'] = "view-field ". views_css_safe('view-field-'. $field['queryname']);
        $row[] = $cell;
      }
    }
    $rows[] = $row;
  }
  $rows += calendar_add_items($view, 'table');
  return theme('table', $view->table_header, $rows);
}

/**
 * Display the nodes of a view as teasers.
 */
function theme_calendar_view_teasers($view, $nodes, $type) {
  return views_theme('calendar_view_nodes', $view, $nodes, 'teasers');
}

/**
 * Display the nodes of a view as plain nodes.
 */
function theme_calendar_view_nodes($view, $nodes, $type, $teasers = false, $links = true) {
	$output = array();
  foreach ($nodes as $n) {
    $node = node_load($n->nid);
    $output[] = node_view($node, $teasers, false, $links);
  }
  $output += calendar_add_items($view, $teasers ? 'teasers' : 'nodes');
  return implode($output);
}

/**
 * Call hooks in other modules to add other items to a calendar view.
 *
 * @param object $view
 * @param string $type - display type, 'table', 'teasers', 'nodes', 'list', 'calendar'
 * @return array of additional items to add.
 */
function calendar_add_items($view, $type) {
	$new_items = array();
  foreach (module_implements('calendar_add_items') as $module) {
    $function = $module .'_calendar_add_items';
    if (function_exists($function)) {
      $feeds = $function($view);
      // Calendar items are just added as objects, themeing will be done by the calendar api.
      // For other types, theme the items and add them.
      foreach ($feeds as $feed) {
    	  if ($type == 'calendar') {
    		  $new_items[] = $feed;
    	  }
    	  else {
    		  switch ($type) {
    			 case 'table':
    			    $output = array('data' => array(theme('calendar_node_month', $feed)));
    				  break;
    			  case 'nodes':
    			  case 'teasers':
    			  case 'list':
    				  $output = theme('calendar_node_day', $feed);
    				  break;
    		  }
    	    if (!empty($output)) $new_items[] = $output;
    	  }
      }
    }
  }
  return $new_items;
}

/**
 * The workhorse function that takes the beginning array of items and alters it
 *   to an array of calendar nodes that the theme can handle.
 */
function calendar_get_nodes(&$view, &$items, $type) {
  calendar_load_calendar_api();
  calendar_load_date_api();

  $view->nodes_per_page = 0;
  $type_names = node_get_types('names');

  unset($params['limit']);

  if ($type == 'block' || $view->calendar_type == 'year') $params['mini'] = TRUE;

  $fields = calendar_fields();
  $calendar_fields = (array) array_keys($fields);
  $nodes = array();
  $i = 0;
  $items_in = $items;

  // explode out field and format info from the view
  foreach ($view->field as $delta => $data) {
    if (in_array($data['field'], $calendar_fields)) {
      $option           = $fields[$data['field']];
      $field_type       = strstr($option['type'], 'string') ? 'string' : 'timestamp';
      $field_function   = strstr($option['type'], 'cck') ? 'content_format' : $data['handler'];
      $field_formatter  = $data['options'];
      $field_field      = $option['query_name'];
      $field_end        = $field_field .'2';
      $field_field_name = $option['field_name'];
      $timestamp_fromto = $option['timestamp_fromto'];
      $string_fromto    = $option['string_fromto'];
      $field_id         = $delta;
      $tz_handling      = $option['tz_handling'];
      $offset_field     = $option['offset_field'];
      $label            = $data['label'];
      $granularity      = $option['granularity'];
      $view_fields      = _views_get_fields();

      // iterate through the $items array returned by the query and create date or pseudo date nodes
      foreach ($items as $delta => $item) {
        // we have to serialize and unserialize to force a completely new copy of $item when duplicate fields use the same node
        // without doing this, values added to the item in later iterations get applied to earlier ones
        $node = unserialize(serialize($item));

        $node->title = $node->node_title;
        $node->label = $label;
        foreach ($view->field as $field) {
          if (!in_array($field['field'], $calendar_fields) && $field['field'] != 'title') {
            if ($view_fields[$field['id']]['visible'] !== FALSE) {
              $node->fields[$field['queryname']] = views_theme_field('views_handle_field', $field['queryname'], $view_fields, $field, $node, $view);
            }
          }
        }
        // If we're dealing with an event node, join the start and to dates together in one node and get rid of the other
        if (module_exists('event') && ($field_field == 'event_event_start' || $field_field == 'event_event_end') && !$event_field_processed[$item->nid]) {
          if ($node->event_event_start > 0) {
            $node->calendar_start = $node->event_event_start;
            $node->calendar_end   = $node->event_event_end;
            $event_field_processed[$item->nid] = TRUE;
          }
        }
        elseif (module_exists('event') && ($field_field == 'event_event_start' || $field_field == 'event_event_end') && $event_field_processed[$item->nid]) {
          // if more than one event field was added to the view (like start and end dates)
          // don't process it more than once
          unset($node);
        }
        if (isset($node) && !isset($node->calendar_start) && !isset($item->$field_field)) {
          // if no date for the node and no date in the item
          // there is no way to display it on the calendar
          unset($node);
        }
        if (isset($node) && !$node->calendar_start && $item->$field_field) {
          // if calendar_start field holds a numeric value, treat it as a unix timestamp
          // if string, convert to timestamp
          if ($field_type == 'timestamp') {
            $node->calendar_start = $item->$field_field;
            $node->calendar_end = $item->$field_end ? $item->$field_end : $item->$field_field;
          } else {
            // get the timestamp value for this date, use UTC to make sure no timezone conversion gets done on it
            $node->calendar_start = date_iso2unix($item->$field_field);
            $node->calendar_end = $item->$field_end ? date_iso2unix($item->$field_end) : date_iso2unix($item->$field_field);
          }
        }
        if (isset($node)) {
          // get appropriate timezone offset
          switch ($tz_handling) {
          case 'user' :
            global $user;
            $node->start_offset = $node->end_offset = $user->timezone;
            break;
          case 'none':
          case 'GMT' :
            $node->start_offset = $node->end_offset = 0;
            break;
          case 'date' :
            $node->start_offset = $node->end_offset = $offset_field;
            break;
          case 'event' :
            include_once(DATE_TIMEZONES);
            $node->start_offset = event_get_offset($node->event_timezone, $node->event_event_start);
            $node->end_offset   = event_get_offset($node->event_timezone, $node->event_event_end);
            break;
          default :
            $node->start_offset = $node->end_offset = variable_get('date_default_timezone', 0);
            break;
          }
        }
        if (isset($node) && function_exists($field_function) && $node->calendar_start && $item->$field_field) {
          if ($field_function == 'content_format') {
            // force the original value for this field into the array that content_format expects
            $node->start_format = content_format($field_field_name, array('value' => $item->$field_field, 'value2' => $item->$field_field), $field_formatter);
            if ($node->calendar_end) $node->end_format = content_format($field_field_name, array('value' => $item->$field_end, 'value2' => $item->$field_end), $field_formatter);
          }
          else {
            // or call date format function
            if (!$node->start_format) {
              $node->start_format = $field_function(NULL, NULL, $item->$field_field, NULL);
              if ($node->calendar_end && !$node->end_format) $node->end_format = $field_function(NULL, NULL, $node->calendar_end, NULL);
            }
          }

          // format a time-only display for the month calendar for dates that have time elements
          if (array_intersect($granularity, array('H', 'N', 'S'))) {
            $node->start_time_format = date_format_date(variable_get('calendar_time_format_'. $view->name, 'H:i'), intval($node->calendar_start + $node->start_offset));
            if ($node->calendar_end) $node->end_time_format   = date_format_date(variable_get('calendar_time_format_'. $view->name, 'H:i'), intval($node->calendar_end + $node->end_offset));
          }
          else {
            $node->start_time_format = $node->start_format;
            $node->end_time_format = $node->end_format;
          }
          if ($node) {
            // we can have multiple representations with the same nid, like multi-day values
            // or different fields that refer to the same node
            // create a unique id so it gets displayed in the calendar
            // Add delta to key to make multiple value CCK fields display as separate items.
            if (strstr($option['type'], 'cck')) {
              $id = $item->nid .':'. $delta .':'. $field_field;
            }
            else {
              $id = $item->nid .':0:'. $field_field;
            }
            $node->nid = $id;

            if ($view->build_type == 'page' && $view->calendar_type != 'year') {
              $node->stripe = calendar_node_stripe($view, $node, $option['query_name'], $field_field);
            }
            $nodes[$id] = $node;
            unset($node);
          }
        }
      }
    }
  }
  // make sure there is at least one item in $nodes to force the calendar to display
  // set the hour to 12 to minimize timezone adjustments that might push it to previous or next day

  if ($view->calendar_type == 'year') {
    // for the year view to work, must have at least one node in each month
    for ($i=1; $i<13; $i++) {
      $nodes[] = _calendar_make_node(NULL, NULL, _views_get_timezone(), $view->year, $i, 1, 12, 0);
    }
  }
  elseif ($view->calendar_type == 'week') {
    // make sure at least one node is created for the current week
    // add both start and end of week in case week crosses from one month to next
    $week_range = calendar_week_range($view->year, $view->week);
    $nodes[]    = _calendar_make_node(NULL, NULL, _views_get_timezone(), date_format_date('Y', $week_range[0]), date_format_date('m', $week_range[0]), date_format_date('j', $week_range[0]), 12, 0);
    $nodes[]    = _calendar_make_node(NULL, NULL, _views_get_timezone(), date_format_date('Y', $week_range[1]), date_format_date('m', $week_range[1]), date_format_date('j', $week_range[1]), 12, 0);
  }
  elseif (sizeof($nodes) == 0) {
    // otherwise add a blank node for the current day
    $nodes = array(_calendar_make_node(NULL, NULL, _views_get_timezone(), $view->year, $view->month, $view->day, 12, 0));
  }

  if (_calendar_is_valid($view->year, 'year')) {

    // valid year is a test that indicates if arguments were available to establish a date for the calendar
    // a full view with an argument date will display a single month, day or week calendar page
    // with navigation that mimics regular calendar

    // trim off date values that are outside the selected range to prevent display of incomplete extra calendars
    $params['limit'] = _calendar_limit_nodes($nodes, $view->calendar_type, $view->year, $view->month, $view->day, $view->week, _views_get_timezone());

    // hide the intermediate header rows created by the event api and
    // push title and navigation into calendar header
    $params['hide_header'] = $view->calendar_type == 'week' ? false : true;
    //$title = theme('calendar_nav_wrapper', calendar_nav($view, $params['mini']), array());

    // standard api displays a whole month instead of a single week
    // adjust here for single week display
    if ($view->calendar_type == 'week' && $view->week) {
      $params['force_week'] = $view->week;
    }
  }
  // use calendar_get_calendar api to draw the calendar
  $params['url'] = calendar_get_url($view, $view->args);
  $params['append'] = calendar_url_append($view);
  $params['stripe'] = 'stripe';
  $params['with_weekno'] = $view->build_type == 'block' || $view->calendar_type == 'year' || $view->year < 1970 ? FALSE : TRUE;

  return array('nodes' => $nodes, 'params' => $params);
}

/**
 *  Function to construct back and next navigation from views arguments
 */
function calendar_nav($view, $mini = FALSE) {
  if (!_calendar_is_valid($view->year, 'year')) {
    return $view->subtitle;
  }
  calendar_load_date_api();

  if ($view->calendar_type == 'week' && _calendar_is_valid($view->week, 'week')) {
    $range = calendar_week_range($view->year, $view->week + 1);
    $cur_stamp = $range[0];
  } else {
    $cur_stamp = date_gmmktime(array('mon' => $view->month ? $view->month : 1, 'mday' => $view->day ? $view->day : 1, 'year' => $view->year ? $view->year : date_format_date("Y", (date_time()))));
  }
  // make the navigation into a header, with prev and next links
  // use the calendar_nav themes to mimic standard calendar navigation
  $paths = calendar_get_paths($cur_stamp, $view);
  $prev_path = implode('/', array_reverse($paths[0]));
  $next_path = implode('/', array_reverse($paths[1]));

  $prev_query = $next_query = array();

  if ($_GET['view']) {
    $prev_query[] = 'view='. $_GET['view'];
    $next_query[] = 'view='. $_GET['view'];
  }
  // for the mini calendar in a block, treat the url as a querystring to avoid actually changing the page
  if ($mini && $view->calendar_type == 'month') {
    $prev_query[] = 'mini='. $prev_path;
    $prev_path = $_GET['q'];
    $next_query[] = 'mini='. $next_path;
    $next_path = $_GET['q'];
  }
  $prev_query[] = calendar_url_append($view);
  $next_query[] = calendar_url_append($view);

  $header = array();
  $header[]  = array('data' => theme('calendar_nav_prev', $prev_path, $mini ? FALSE : TRUE, implode('&', $prev_query)), 'class' => 'prev');
  $header[]  = array('data' => $view->subtitle, 'class' => 'heading', 'colspan' => 5);
  $header[]  = array('data' => theme('calendar_nav_next', $next_path, $mini ? FALSE : TRUE, implode('&', $next_query)), 'class' => 'next');

  return $header;
}

function calendar_get_paths($cur_stamp, $view) {
  calendar_load_date_api();
  $path = array();

  // build an array of the current path and its parts
  $i = 0;
  $path[$i]     = array(
    'path' => $view->real_url,
    'type' => 'url',
      );
  foreach ($view->argument as $delta => $arg) {
    if ($view->args[$delta]) {
      $i++;
      $pathtype = str_replace('calendar_', '', $arg['type']);
      $path[$i] = array(
        'path' => $view->args[$delta] != CALENDAR_EMPTY_ARG ? $view->$pathtype : CALENDAR_EMPTY_ARG,
        'type' => $pathtype,
        );
    }
  }
  // if there are other arguments after the view arguments, add them to the navigation links
  while($i < sizeof($view->args)) {
    $i++;
    $path[$i] = array(
      'path' => $view->args[intval($i - 1)],
      'type' => '',
    );
  }

  // reverse through the path, creating a $nextpath and $prevpath arrays
  for ($x = $i; $x >= 0; $x--) {
    if ($path[$x]['path'] != CALENDAR_EMPTY_ARG) {
      switch ($path[$x]['type']) {
      case ('day'):
      	$day = $path[$x]['path'];
        $next_stamp = $cur_stamp + (86400);
        $prev_stamp = $cur_stamp - (86400);
        $nextpath[$x] = date_format_date('j', $next_stamp);
        $prevpath[$x] = date_format_date('j', $prev_stamp);
        break;
      case ('week'):
        $week = $path[$x]['path'];
        $year = $view->year;
        if (!$next_stamp) {
          $cal_range = calendar_week_range($year, $week);
          $next_stamp = $cal_range[1] + 1;
          $prev_stamp = $cal_range[0] - 1;
        }
        $week_year = calendar_week_year($next_stamp);
        $next_year = $week_year[1];
        $nextpath[$x] = 'W'. sprintf("%02d", $week_year[0]);
        $week_year = calendar_week_year($prev_stamp);
        $prev_year = $week_year[1];
        $prevpath[$x] = 'W'. sprintf("%02d", $week_year[0]);
        break;
      case ('month'):
        $month = $path[$x]['path'];
        $year  = $view->year;
        $next_year = $month < 12 ? $year : $year + 1;
        $prev_year = $month > 1 ? $year : $year - 1;
        if (!$next_stamp) {
          $next_stamp = date_gmmktime(array('mon' => $month < 12 ? $month + 1 : 1, 'mday' => 1, 'year' => $next_year));
          $prev_stamp = date_gmmktime(array('mon' => $month > 1  ? $month - 1 : 12, 'mday' => 1, 'year' => $prev_year));
        }
        $nextpath[$x] = date_format_date('n', $next_stamp);
        $prevpath[$x] = date_format_date('n', $prev_stamp);
        break;
      case ('year'):
        $year = $view->year;
        if (!$next_stamp) {
          $next_stamp = date_gmmktime(array('mon' => 1, 'mday' => 1, 'year' => $next_year ? $next_year : $year + 1));
          $prev_stamp = date_gmmktime(array('mon' => 12, 'mday' => 1, 'year' => $prev_year ? $prev_year : $year - 1));
        }
        $nextpath[$x] = date_format_date('Y', $next_stamp);
        $prevpath[$x] = date_format_date('Y', $prev_stamp);
        break;
      default:
        // all other arguments are just passed through
        if ($path[$x]['path']) {
          $nextpath[$x] = $path[$x]['path'];
          $prevpath[$x] = $path[$x]['path'];
        }
        break;
      }
    }
    else {
       $nextpath[$x] = $path[$x]['path'];
       $prevpath[$x] = $path[$x]['path'];
    }
  }
  return array($prevpath, $nextpath);
}

/**
 *  A function to create a blank date to force a calendar display when there is no data
 */
function _calendar_make_node($node = NULL, $timestamp = NULL, $offset = NULL, $year = NULL, $month = NULL, $day = NULL, $hour = NULL, $minute = NULL) {
  calendar_load_date_api();
  $offset = $offset ? $offset : _views_get_timezone();

  if (!$timestamp) {
    $year   = _calendar_is_valid($year, 'year')     ? $year   : date_format_date('Y', date_time());
    $month  = _calendar_is_valid($month, 'month')   ? $month  : date_format_date('m', date_time());
    $day    = _calendar_is_valid($day, 'day')       ? $day    : date_format_date('j', date_time());
    $hour   = _calendar_is_valid($hour, 'hour')     ? $hour   : date_format_date('H', date_time());
    $minute = _calendar_is_valid($minute, 'minute') ? $minute : date_format_date('i', date_time());
    while (!checkdate($month, $day, $year)) $day--; // Account for days that don't exist
    $timestamp = date_gmmktime(array('hours' => $hour, 'minutes' => $minute, 'mon' => $month, 'mday' => $day, 'year' => $year));
  }

  if (!$node) {
    $node = new stdClass();
    $node->nid = 0;
  }
  $node->calendar_start = $timestamp;
  $node->start_offset   = $offset;
  $node->calendar_end   = $timestamp;
  $node->end_offset     = $offset;

  return $node;
}

/**
 *  A function to adjust node values to slice off times before and after the selected view
 *  used for calendars that span days, months, or years since the calendar api
 *  automatically creates additional calendars for calendars that extend into another time period
 *  and the additional calendars will be incomplete (only containing cross-over calendars)
 */
function _calendar_limit_nodes($nodes, $type, $year, $month, $day, $week, $offset) {
  calendar_load_date_api();
  if (!_calendar_is_valid($day, 'day')) $day = 1;
  if (!_calendar_is_valid($month, 'month')) $month = date_format_date('m', date_time());
  if (!_calendar_is_valid($year, 'year')) $year = date_format_date('Y', date_time());

  switch ($type) {
  case ('day'):
    $min_date = date_gmmktime(array('mon' => $month, 'mday' => $day, 'year' => $year));
    $max_date = $min_date + 86400 - 1;
    break;
  case ('week'):
    return calendar_week_range($year, $week);
  case ('month');
    $min_date = date_gmmktime(array('mon' => $month, 'mday' => 1, 'year' => $year));
    // find the first day of the next month and subtract one day
    if (intval($month) < 12) {
      $max_date = date_gmmktime(array('mon' => intval($month + 1), 'day' => 1, 'year' => $year, 'hours' => 23, 'minutes' => 59, 'seconds' => 59));
    } else {
      $max_date = date_gmmktime(array('mon' => 1, 'mday' => 1, 'year' => intval($year + 1), 'hours' => 23, 'minutes' => 59, 'seconds' => 59));
    }
    break;
  case ('year'):
    $min_date = date_gmmktime(array('hours' => 0, 'minutes' => 0, 'seconds' => 0, 'mon' => 1, 'mday' => 1, 'year' => $year));
    $max_date = date_gmmktime(array('hours' => 23, 'minutes' => 59, 'seconds' => 59, 'mon' => 12, 'mday' => 31, 'year' => $year));
  }
  return array($min_date, $max_date);
}

/**
 *  TODO need to identify type of timezone handling needed for each date field
 */
function calendar_offset($field_name) {
  $default_offset = variable_get('date_default_timezone', 0);
  $configurable_zones = variable_get('configurable_timezones', 1);
}

/**
 *  Implementation of hook_views_arguments()
 */
function calendar_views_arguments() {
  $arguments = array(
    'calendar_year' => array(
      'name' => t('Calendar: Year'),
      'handler' => 'calendar_handler_arg_year',
      'help' => t('Filter by the calendar year (YYYY).'),
    ),
    'calendar_month' => array(
      'name' => t('Calendar: Month'),
      'handler' => 'calendar_handler_arg_month',
      'help' => t("Filter by the calendar month (1-12). Place this argument after a 'Year' argument."),
    ),
    'calendar_day' => array(
      'name' => t('Calendar: Day'),
      'handler' => 'calendar_handler_arg_day',
      'help' => t("Filter by the calendar day (1-31). Place this argument after a 'Year' and a 'Month' argument."),
    ),
    'calendar_week' => array(
      'name' => t('Calendar: Week'),
      'handler' => 'calendar_handler_arg_week',
      'help' => t("Filter by the week number (1-52). Place this argument after a 'Year' argument and use a 'W' in front of the week number in the url."),
    ),
  );
  return $arguments;
}

/**
 *  Custom views handler for the year argument.
 */
function calendar_handler_arg_year($op, &$query, $argtype, $arg = '') {
  if ($op == 'filter' && !empty($arg) && $arg != CALENDAR_EMPTY_ARG) {
		calendar_filter_year($query, $arg);
  }
  return calendar_handler_arg_type($op, $query, $argtype, $arg, 'YEAR');
}

/**
 * Callback for year filter.
 *   Build year, month, day, min, and max into query object.
 *
 * @param object $query
 * @param integer $arg
 */
function calendar_filter_year(&$query, $arg) {
	calendar_load_calendar_api();
	$query->calendar_type = 'year';
  $query->year = _calendar_is_valid($arg, 'year') ? $arg : calendar_user_date('year');
  $query->month = CALENDAR_EMPTY_ARG;
  $query->day = CALENDAR_EMPTY_ARG;
  $query->min = $query->year;
  $query->max = $query->year;
}

/**
 *  Custom views handler for the month argument.
 */
function calendar_handler_arg_month($op, &$query, $argtype, $arg = '') {
	if ($op == 'filter' && !empty($arg) && $arg != CALENDAR_EMPTY_ARG) {
		calendar_filter_month($query, $arg);
	}
	return calendar_handler_arg_type($op, $query, $argtype, $arg, 'MONTH');
}

/**
 * Callback for month filter.
 *   Build year, month, day, min, and max into query object.
 *
 * @param object $query
 * @param integer $arg
 */
function calendar_filter_month(&$query, $arg) {
  calendar_load_calendar_api();
  $query->calendar_type = 'month';
  if (!isset($query->year)) {
  	calendar_filter_year($query, calendar_user_date('year'));
  }
  $query->month = _calendar_is_valid($arg, 'month') ? $arg : calendar_user_date('month');
  $query->day = CALENDAR_EMPTY_ARG;
  $query->min .= '-'. sprintf('%02d', $query->month);
  $query->max .= '-'. sprintf('%02d', $query->month);
}

/**
 *  Custom views handler for the day argument.
 */
function calendar_handler_arg_day($op, &$query, $argtype, $arg = '') {
	if ($op == 'filter' && !empty($arg) && $arg != CALENDAR_EMPTY_ARG) {
	  calendar_filter_day($query, $arg);
	}
	return calendar_handler_arg_type($op, $query, $argtype, $arg, 'DAY');
}

/**
 * Callback for day filter.
 *   Build year, month, day, min, and max into query object.
 *
 * @param object $query
 * @param integer $arg
 */
function calendar_filter_day(&$query, $arg) {
  calendar_load_calendar_api();
  if (!isset($query->month)) {
  	calendar_filter_month($query, calendar_user_date('month'));
  }
  $query->calendar_type = 'day';
  $query->day = _calendar_is_valid($arg, 'day') ? $arg : calendar_user_date('day');
  $query->min .= '-'. sprintf('%02d', $query->day);
  $query->max .= '-'. sprintf('%02d', $query->day);
}

/**
 *  Custom views handlers for the week argument.
 */
function calendar_handler_arg_week($op, &$query, $argtype, $arg = '') {
	if ($op == 'filter' && !empty($arg) && $arg != CALENDAR_EMPTY_ARG) {
	  calendar_filter_week($query, $arg);
	}
	return calendar_handler_arg_type($op, $query, $argtype, $arg, 'WEEK');
}

/**
 * Callback for week filter.
 *   Build year, month, day, min, and max into query object.
 *
 * @param object $query
 * @param integer $arg
 */
function calendar_filter_week(&$query, $arg) {
	calendar_load_calendar_api();
	if (!isset($query->year)) {
  	calendar_filter_year($query, calendar_user_date('year'));
  }
  $arg = str_replace('W', '', $arg);
	$query->calendar_type = 'week';
  $query->week = _calendar_is_valid($arg, 'week') ? $arg : calendar_user_date('week');
  $query->month = calendar_week('start_month', $query, $query->week);
  $query->day = calendar_week('start_day', $query, $query->week);
  $query->min = calendar_week('start_year', $query, $query->week) .'-'. sprintf('%02d', calendar_week('start_month', $query, $query->week)) .'-'. calendar_week('start_day', $query, $query->week) .' 00:00:00';
  $query->max = calendar_week('end_year', $query, $query->week) .'-'. sprintf('%02d', calendar_week('end_month', $query, $query->week)) .'-'. calendar_week('end_day', $query, $query->week) .' 23:59:59';
}

/**
 *  Custom views handler for all calendar arguments.
 */
function calendar_handler_arg_type($op, &$query, $argtype, $arg, $field_type) {
	calendar_load_date_api();
  switch ($op) {
  	case 'summary':
  	case 'link':
  		// The query to do summaries when date rangess can include multiple days, months, and years
  		// is extremely complex and has been omitted, so summary views with these arguments just will not work.
  		// TODO add some kind of validation or warning to keep people from trying to use summary views.
  		break;

  	case 'filter':
  		// Figure out which will be the final calendar argument in this view so we know when to insert the query.
      $view = $GLOBALS['current_view'];
      if ($argtype['type'] == calendar_last_argtype($view)) {
  			$query->calendar_finished = TRUE;
      	calendar_build_filter($query, $view);
      }
      break;

    case 'title':
    	// Set titles for each argument.
      $value = intval(str_replace('W', '', $arg ? $arg : $query));
      return theme('calendar_arg_title', $field_type, $value, $query);
  }
  return;
}

/**
 * Compile the filter query for this view.
 *
 * @param object $query
 * @param object $view
 */
function calendar_build_filter(&$query, &$view) {
  if (!isset($query->week)) {
  	$query->week  = calendar_week('week', $query);
  }
  if (!$query->min) {
    return;
  }

  // Add elements to the query min and max values to create a complete date value
  // for the minimum and maximum once all the View's args have been used.
  $minmax = array(
    'year' => array('-01-01 00:00:00', "-12-31 23:59:59"),
    'month' => array('-01 00:00:00', '-'. sprintf("%02d", date_last_day_of_month($query->month, $query->year)) .' 23:59:59'),
    'day' => array(' 00:00:00', ' 23:59:59'),
    'hour' => array(':00:00', ':59:59'),
    'minute' => array(':00', ':59'),
  );
  $query->min .= $minmax[$query->calendar_type][0];
  $query->max .= $minmax[$query->calendar_type][1];

  // find all datetime fields in this view and add filters for them to the query
  $queries = array();
  foreach ($view->field as $delta => $field) {
    $query_strings = calendar_build_field_query($query, $field);
    if (!empty($query_strings)) $queries = array_merge($queries, $query_strings);
  }
  // bring the node type into the query so we can use it in the theme
  $query->add_field('type', 'node');
  if ($queries) $query->add_where(implode(" OR ", $queries));
  return;
}

/**
 * Build a filtering query for an individual date field
 *
 * @param object $query - the query object
 * @param array $field - the view field array
 */
function calendar_build_field_query(&$query, $field) {
	$queries = array();
	$fields = calendar_fields();
  $field_name = $field['field'];
  $this_field = $fields[$field_name];
  $view_fields[] = $field_name;

  if (array_key_exists($field_name, $fields)) {
    $query->ensure_table($this_field['table'], $this_field['table']);
    $tz_handling  = $this_field['tz_handling'];
    $offset_field = $this_field['offset_field'];
    $field_type   = strstr($this_field['type'], 'string') ? 'iso' : 'int';

    // get appropriate timezone offset
    switch ($tz_handling) {
      case 'user' :
       global $user;
        $start_offset = $end_offset = $user->timezone;
        break;
      case 'none':
      case 'GMT':
        $start_offset = $end_offset = 0;
        break;
      case 'date' :
        $start_offset = $end_offset = $offset_field;
        break;
      case 'event' :
        // event-specific timezones won't work right here because no offset is stored in the database
        // the best we can do is treat it the same as if it was a site timezone
      default :
        $start_offset = $end_offset = variable_get('date_default_timezone', 0);
        break;
    }

    // handling for from and to date ranges
    if ($this_field['timestamp_fromto']) {
      $queries[] = "(". date_sql('DATE', $this_field['timestamp_fromto'][1], $field_type, $end_offset) ." >='". $query->min ."' AND ". date_sql('DATE', $this_field['timestamp_fromto'][0], $field_type, $start_offset) ." <='". $query->max ."')";
      $event_field_processed = TRUE;
    }
    elseif ($this_field['string_fromto']) {
      $queries[] = "(". date_sql('DATE', $this_field['string_fromto'][1], $field_type, $end_offset) ." >='". $query->min ."' AND ". date_sql('DATE', $this_field['string_fromto'][0], $field_type, $start_offset) ." <='". $query->max ."')";
      $event_field_processed = TRUE;
    }
    // handling for single day dates
    elseif ($this_field['type'] == 'cck_string') {
      $queries[] = "(". date_sql('DATE', $this_field['fullname'], $field_type, $start_offset) .">='". $query->min ."' AND ". date_sql('DATE', $field['fullname'], $field_type, $end_offset) ."<='". $query->max ."')";
    }
    elseif (strstr($this_field['type'], 'timestamp')) {
      $queries[] = "(". date_sql('DATE', $this_field['fullname'], $field_type, $start_offset) .">='". $query->min ."' AND ". date_sql('DATE', $this_field['fullname'], $field_type, $end_offset) ."<='". $query->max ."')";
    }
  }
  return $queries;
}

/**
 *  Implementation of hook_views_query()
 *    Insert filters into the query based on the current calendar view and the selected fields
 *    Used when the actual view arguments don't provide enough info to construct the query.
 *    i.e. on a view with no arguments or one with partial arguments like year or year/month.
 *
 *  @param object $query
 *  @param object $view
 */
function calendar_views_query_alter(&$query, &$view) {
	if (!calendar_has_calendar_args($view)) {
  		return;
  }
  $view->real_url = calendar_get_url($view, $view->args);
  calendar_load_calendar_api();
  calendar_load_date_api();

  // make sure block views default to the current month
  // and make sure day view is not selected

  if ($view->build_type == 'block') {
    $query->calendar_type = 'month';
    $view->args = explode('/', str_replace($view->url .'/', '', $_GET['mini']));
    foreach ($view->argument as $delta => $argument) {
      if ($argument['type'] == 'calendar_year') {
        if (!$view->args[$delta]) $view->args[$delta] = calendar_user_date('year');
        $query->year = $view->args[$delta];
        calendar_filter_year($query, $query->year);
      }
      elseif (($argument['type'] == 'calendar_month' || $argument['type'] == 'calendar_week')) {
        if (!$view->args[$delta]) $view->args[$delta] = calendar_user_date('month');
        $query->month = $view->args[$delta];
        calendar_filter_month($query, $query->month);
      }
      elseif ($argument['type'] == 'calendar_day') {
      	$query->day = CALENDAR_EMPTY_ARG;
        $view->args[$delta] = CALENDAR_EMPTY_ARG;
      }
    }
  }

  // Either a month or a week argument could occupy the second position of the group
  // this is done so that a single view has the capability to switch between all calendar layouts
  // to make this work we must make some adjustments to the view

  if ($view->build_type == 'page') {
    $GLOBALS['calendar_is_calendar'] = TRUE;

    if (empty($view->args)) {

    	// If no arguments are provided, default to current month view.
    	$query->calendar_type = 'month';
      foreach ($view->argument as $delta => $argument) {
        if ($argument['type'] == 'calendar_year' && !$view->args[$delta]) {
          $view->args[$delta] = calendar_user_date('year');
          calendar_filter_year($query, calendar_user_date('year'));
        }
        elseif ($argument['type'] == 'calendar_month' && !$view->args[$delta]) {
          $view->args[$delta] = calendar_user_date('month');
          calendar_filter_month($query, calendar_user_date('month'));
        }
        elseif ($argument['type'] == 'calendar_day' && !$view->args[$delta]) {
          $view->args[$delta] = CALENDAR_EMPTY_ARG;
        }
      }
    }

    foreach ($view->argument as $delta => $argument) {
      if (in_array($argument['type'], array('calendar_year', 'calendar_month', 'calendar_day', 'calendar_week'))) {
        // make sure 'display all values' is selected for the calendar arguments
        // summary views are meaningless and create errors in this context
        $view->argument[$delta]['argdefault'] = 2;

        // Pad any unused values in the view arguments with CALENDAR_EMPTY_ARG to indicate all values.
        if (empty($view->args[$delta])) {
        	$view->args[$delta] = CALENDAR_EMPTY_ARG;
        }
      }

      // Calendar_week and Calendar_month can swap positions as the second arg in the url.
      // Do some work here to make sure we know which is which and swap view data to match it.
      // the difference between a calendar_month arg and a calendar_week arg is the preceeding 'W'
      if ($argument['type'] == 'calendar_week' || $argument['type'] == 'calendar_month') {

        if (strstr($view->args[$delta], 'W')) {
        	calendar_filter_week($query, $view->args[$delta]);
          $view->argument[$delta]['type'] = 'calendar_week';
          $view->argument[$delta]['id'] = 'calendar_week';
          $view->argument[$delta + 1]['type'] = 'calendar_day';
          $view->argument[$delta + 1]['id'] = 'calendar_day';

          // Make sure that there is no day set for the week view.
          $view->args[$delta + 1] = CALENDAR_EMPTY_ARG;
        }
        // if this is not a week argument and view was created with a week argument, change it back
        elseif (!strstr($view->args[$delta], 'W') && $view->build_type == 'page' && $view->argument[$delta]['type'] == 'calendar_week') {
          calendar_filter_month($query, $view->args[$delta]);
          $view->argument[$delta]['type'] = 'calendar_month';
          $view->argument[$delta]['id'] = 'calendar_month';
          $view->argument[$delta + 1]['type'] = 'calendar_day';
          $view->argument[$delta + 1]['id'] = 'calendar_day';
        }
      }
    }
  }

  // Make sure the calendar query gets inserted. May not have finished yet on views like year or year/month.
  if (!$query->calendar_finished) {
  	calendar_build_filter($query, $view);
  }

  $view->calendar_type = $query->calendar_type;
  $view->year = $query->year;
  $view->month = $query->month;
  $view->day = $query->day;
  $view->week = $query->week;

}

/**
 *  Implementation of hook_views_pre_view()
 */
function calendar_views_pre_view(&$view, &$items) {

	// If no part of this view has calendar elements, exit.
	if (!calendar_is_calendar($view) && !calendar_has_calendar_args($view)) {
		return;
	}

	// Construct a formatted title for the view from the last calendar argument encountered.
  switch ($view->calendar_type) {
    case 'year':
      $view->subtitle = theme('calendar_nav_title', 'YEAR', $view);
  		break;
    case 'month':
      $view->subtitle = theme('calendar_nav_title', 'MONTH', $view);
  	 break;
    case 'day':
      $view->subtitle = theme('calendar_nav_title', 'DAY', $view);
      break;
    case 'week':
      $view->subtitle = theme('calendar_nav_title', 'WEEK', $view);
     break;
  }

  // If this is a view with calendar arguments but not a calendar view,
  // add navigation to the top of the view and return.
  if (!calendar_is_calendar($view) && calendar_has_calendar_args($view)) {
    return theme('calendar_show_nav', $view,  $view->build_type == 'block', calendar_is_calendar($view));
  }

  // If this is a calendar plugin theme view, make sure empty results
  // will produce blank calendar page
  if (array_key_exists($view->page_type, calendar_view_types())) {
    if (!$items && $view->build_type == 'page' && $view->year) {
      $view->page_empty = $view->page_header . $view->page_empty . theme('calendar_display', $view, array(), 'page');
      $view->page_empty_format = 3;
    }
  }
  if (array_key_exists($view->block_type, calendar_view_types())) {
    if (!$items && $view->build_type == 'block' && $view->year) {
      $view->block_empty = $view->block_header . $view->block_empty . theme('calendar_display', $view, array(), 'block');
      $view->block_empty_format = 3;
    }
  }
}

/**
 * Get the start and end datestamp for a calendar week.
 */
function calendar_week_range($year, $week) {
	calendar_load_date_api();
  // Get timestamp for January 1 of the requested year.
  $min_date = date_gmmktime(array('mon' => 1, 'mday' => 1, 'year' => $year));
  // Adjust back or forward to the first day of the calendar week for the specified first day of week.
  $dow = date_format_date('w', $min_date);
  $first_day = variable_get('date_first_day', 0);
  $diff = -((7 - $first_day + $dow) % 7);
  $min_date += $diff * 86400;
  // Add the requested number of weeks to that date.
  $min_date += intval(($week - 1) * 604800);
  // Find the end date, which is one week later, less one second.
  $max_date = $min_date + 604800 - 1;
  return array($min_date, $max_date);
}

/**
 * Find the calendar week number and year for a date.
 *
 * This is complicated by the fact that the calendar week does not match the ISO week,
 * since the ISO week starts on Monday for the first week that has 4 or more days in the new year
 * while the calendar week starts on the site's preferred first day of the week regardless
 * of the number of days that are in the first week or the year.
 *
 * @param unknown_type $timestamp
 * @return array of calendar week number and year
 */
function calendar_week_year($timestamp) {
  $first_day = variable_get('date_first_day', 0);
  $iso_week = intval(date_format_date('W', $timestamp));
  $year = date_format_date('Y', $timestamp);
  // Where does this timestamp fall within the range for the iso week number.
  $range = calendar_week_range($year, $iso_week);
  // If the timestamp is in the range, the ISO week number is correct.
  if ($timestamp >= $range[0] && $timestamp <= $range[1]) {
    return array($iso_week, $year);
  }
  // If the timestamp is earlier, the calendar week is earlier than the ISO week.
  elseif ($timestamp < $range[1]) {
  	if ($iso_week >= 2) {
  		return array(intval($iso_week - 1), $year);
  	}
  	else {
  		return array(1, $year);
  	}
  }
  // If the timestamp is later, the calendar week is later than the ISO week.
  elseif ($timestamp > $range[0]) {
    if ($iso_week < 52) {
    	return array(intval($iso_week + 1), $year);
    }
    else {
      return array(1, intval($year + 1));
  	}
  }
}

/**
 *  Handle a lot of messy week calculations all in one place to make maintenance easier
 */
function calendar_week($op, $view, $week = 0) {
  calendar_load_date_api();
	if ($week == 0) {
  	$day = !empty($view->day) && $view->day != CALENDAR_EMPTY_ARG ? $view->day : calendar_user_date('day');
  	$month = !empty($view->month) && $view->month != CALENDAR_EMPTY_ARG ? $view->month : calendar_user_date('month');
		$isodate = $view->year .'-'. sprintf('%02d', $month) .'-'. sprintf('%02d', $day) .'T00:00:00';
  	$week_year = calendar_week_year(date_iso2unix($isodate));
  	if ($op == 'week') return $week_year[0];
  }
  $range = calendar_week_range($view->year, $week);
  $week_start = $range[0];
  $week_end = $range[1];
  switch ($op) {
  case ('start_year'):
    return date_format_date('Y', $week_start);
  case ('end_year'):
    return date_format_date('Y', $week_end);
  case ('start_month'):
    return date_format_date('n', $week_start);
  case ('end_month'):
    return date_format_date('n', $week_end);
  case ('start_day'):
    return date_format_date('d', $week_start);
  case ('end_day'):
    return date_format_date('d', $week_end);
  default:
    return $week_start;
  }
}

/**
 *  A function to test the validity of various date parts
 */
function _calendar_is_valid($value, $type) {
  calendar_load_date_api();
  $value = intval($value);
  if ($value <= 0) return false;
  switch ($type) {
  case ('year'):
    if ($value < DATE_MIN_YEAR) return false;
    break;
  case ('month'):
    if ($value < 0 || $value > 12) return false;
    break;
  case ('day'):
    if ($value < 0 || $value > 31) return false;
    break;
  case ('week'):
    if ($value < 0 || $value > 53) return false;
  }
  return true;
}

function calendar_views_default_views() {
$view = new stdClass();
  $view->name = t('calendar');
  $view->description = t('Calendar view of any date field');
  $view->access = array ();
  $view->view_args_php = '';
  $view->page = TRUE;
  $view->page_title = t('Calendar');
  $view->page_header = "";
  $view->page_header_format = '1';
  $view->page_footer = "";
  $view->page_footer_format = '1';
  $view->page_empty = "";
  $view->page_empty_format = '1';
  $view->page_type = 'calendar';
  $view->url = t('calendar');
  $view->use_pager = FALSE;
  $view->nodes_per_page = '0';
  $view->block = TRUE;
  $view->block_title = t('Calendar');
  $view->block_header = "";
  $view->block_header_format = '1';
  $view->block_footer = "";
  $view->block_footer_format = '1';
  $view->block_empty = "";
  $view->block_empty_format = '1';
  $view->block_type = 'calendar';
  $view->nodes_per_block = '99';
  $view->block_more = '1';
  $view->block_use_page_header = FALSE;
  $view->block_use_page_footer = FALSE;
  $view->block_use_page_empty = FALSE;
  $view->sort = array (
    array (
      'tablename' => 'node',
      'field' => 'changed',
      'sortorder' => 'ASC',
      'options' => '',
    ),
  );
  $view->argument = array (
    array (
      'type' => 'calendar_year',
      'argdefault' => '2',
      'title' => '%1',
      'options' => '',
      'wildcard' => '',
      'wildcard_substitution' => '',
    ),
    array (
      'type' => 'calendar_month',
      'argdefault' => '2',
      'title' => '%2',
      'options' => '',
      'wildcard' => '',
      'wildcard_substitution' => '',
    ),
    array (
      'type' => 'calendar_day',
      'argdefault' => '2',
      'title' => '%3',
      'options' => '',
      'wildcard' => '',
      'wildcard_substitution' => '',
    ),
  );
  $view->field = array (
    array (
      'tablename' => 'node',
      'field' => 'title',
      'label' => 'Title:',
      'handler' => 'views_handler_field_nodelink',
      'options' => 'link',
    ),
    array (
      'tablename' => 'node',
      'field' => 'changed',
      'label' => 'Updated:',
      'handler' => 'views_handler_field_date_small',
    ),
  );
  $view->filter = array (
    array (
      'tablename' => 'node',
      'field' => 'status',
      'operator' => '=',
      'options' => '',
      'value' => '1',
    ),
  );
  $view->exposed_filter = array (
  );
  $view->requires = array(node);
  $views[$view->name] = $view;
  return $views;
}

/**
 *  implementation of hook_block()
 */
function calendar_block($op = 'list', $delta = 0) {
  switch ($op) {
    case 'list' :
      $blocks[0]['info'] = t('Calendar Legend.');
      $blocks[1]['info'] = t('Switch Calendar.');
      return $blocks;
      break;
    case 'view' :
      switch ($delta) {
      case 0:
        $block['subject'] = t('Calendar Legend');
        $block['content'] = $GLOBALS['calendar_stripe_labels'] ? '<div class="calendar legend">'. theme('calendar_stripe_legend', $GLOBALS['calendar_stripe_labels']) .'</div>' : '';
        return $block;
      case 1:
        $block['subject'] = t('Switch Calendar');
        $block['content'] = $GLOBALS['calendar_is_calendar'] ? drupal_get_form('calendar_switch_view') : '';
        return $block;
      }
  }
}

/**
 *  A block with a drop-down list that allows the user to switch between views of the current period
 */
function calendar_switch_view() {

  $options[''] = t('Calendar');
  $options['list'] = t('List');
  $options['teasers'] = t('Teasers');
  $options['nodes'] = t('Nodes');
  $options['table'] = t('Table');

  $form = array(
    '#method' => 'GET',
    'view' => array(
      '#type' => 'select',
      '#default_value' => $_GET['view'],
      '#options' => $options,
      ),
    'q' => array(
      '#type' => 'hidden',
      '#value' => $_GET['q'],
      ),
    'submit' => array('#type' => 'submit', '#value' => t('Switch')),
    );
  return $form;
}

/**
 *  Implementation of hook_calendar_node() from the calendar_get_calendar() api
 *  calendar api is expecting a function for each calendar type but
 *  all of them need the same processing, so run them through a single function
 *  instead of duplicating the processing for each one
 */
function calendar_calendar_node_month($node) {
  return calendar_calendar_node($node, 'calendar_node_month');
}
function calendar_calendar_node_day($node) {
  return calendar_calendar_node($node, 'calendar_node_day');
}
function calendar_calendar_node_week($node) {
  return calendar_calendar_node($node, 'calendar_node_week');
}
function calendar_calendar_node($node, $type) {
  calendar_load_calendar_api();
  if ($node->nid && $node->nid !== 0 && $node->calendar_start) {
    // this is a real calendar, go ahead and display it
    if (!$node->remote) {
      // switch our psuedo nids back to the right values
      $tmp = explode(':', $node->nid);
      $node->nid = $tmp[0];
    }
    return theme('calendar_calendar_node', $node, $type);

  } else {
    // surpress display of psuedo calendars added to force display of a blank calendar
    // have to return some value for blank day so not overridden by normal calendar node theme
    // a blank space seems to be sufficient to do that
    return ' ';
  }
}

/**
 * Figure out what the URL of the calendar view we're currently looking at is.
 */
function calendar_get_url($view, $args) {
  static $cal_args;
  // Figure out which arguments are calendar arguments.
  if (!is_array($cal_args)) $cal_args = array();
  if (empty($cal_args[$view->name])) {
  	foreach ($view->argument as $delta => $arg) {
      if (in_array($arg['type'], array('calendar_year', 'calendar_week', 'calendar_month', 'calendar_day', 'calendar_ical'))) {
        $cal_args[$view->name][] = $delta;
      }
    }
  }
  // Add non-calendar arguments to the base url.
  $parts = array($view->url);
  foreach ($args as $delta => $arg) {
    if (!in_array($delta, $cal_args[$view->name]) && $arg) {
      array_push($parts, $arg);
    }
  }
  return implode('/', $parts);
}

/**
 * Pick up filter and sort info from url.
 */
function calendar_url_append($view) {
  if ($view->build_type == 'page') {
    foreach ($_GET as $key => $val) {
      if ($key != 'q' && $key != 'view') {
        if (!is_array($val)) {
          $url .= '&'. $key .'='. $val;
        }
        else {
          foreach ($val as $v) {
            $url .= '&'. $key .'[]='. $v;
          }
        }
      }
    }
  }
  return $url;
}

/**
 * Setup Calendar parameters.
 */
function calendar_setup_form($view_name) {
	calendar_load_date_api();
	$view = views_load_view($view_name);
  $form = array();
  $time = mktime(1, 15, 0, 1, 1, date('Y', date_time()));
  $time_options = array(
    'G:i' => date('G:i', $time),
    'g:ia' => date('g:ia', $time),
    'g:iA' => date('g:iA', $time),
    'g:i a' => date('g:i a', $time),
    'g:i A' => date('g:i A', $time),
    'H:i' => date('H:i', $time),
    'h:ia' => date('h:ia', $time),
    'h:iA' => date('h:iA', $time),
    'h:i a' => date('h:i a', $time),
    'h:i A' => date('h:i A', $time),
    );

  $form['calendar_time_format'] = array(
    '#title' => t('Time format'),
    '#default_value' => variable_get('calendar_time_format_'. $view->name, 'H:i'),
    '#type' => 'select',
    '#options' => $time_options,
    '#description' => t('The format to use for the time-only date display.'),
    );
  $display_options = array('calendar' => t('Calendar'), 'table' => t('Table'), 'teasers' => t('Teasers'), 'nodes' => t('Full Nodes'), 'list' => t('List'));
  $display_format = variable_get('calendar_display_format_'. $view->name, array('year' => 'calendar', 'month' => 'calendar', 'week' => 'calendar', 'day' => 'calendar', 'block' => 'calendar'));
  $form['year'] = array(
    '#title' => t('Year display'),
    '#default_value' => $display_format['year'],
    '#type' => 'select',
    '#options' => $display_options,
  );
  $form['month'] = array(
    '#title' => t('Month display'),
    '#default_value' => $display_format['month'],
    '#type' => 'select',
    '#options' => $display_options,
  );
  $form['week'] = array(
    '#title' => t('Week display'),
    '#default_value' => $display_format['week'],
    '#type' => 'select',
    '#options' => $display_options,
  );
  $form['day'] = array(
    '#title' => t('Day display'),
    '#default_value' => $display_format['day'],
    '#type' => 'select',
    '#options' => $display_options,
  );
  $form['block'] = array(
    '#title' => t('Block display'),
    '#default_value' => $display_format['block'],
    '#type' => 'select',
    '#options' => $display_options,
  );
  $form['calendar_empty_arg'] = array(
    '#title' => t('Wildcard argument'),
    '#type' => 'textfield',
    '#default_value' => variable_get('calendar_empty_arg', 'all'),
    '#description' => t('A character or short text string to use for empty calendar arguments. For instance, \'all\' would create the url 2007/12/all to show all days in December of 2007. Note that non-ASCII characters will not display correctly in urls.')
    );
  $form['view_name'] = array(
    '#type' => 'hidden',
    '#value' => $view->name,
    );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
    );
  return $form;
}

/**
 * Save requested values.
 */
function calendar_setup_form_submit($form_id, $form_values) {
  $view_name = $form_values['view_name'];
  $display_format = array();
  variable_set('calendar_empty_arg', check_plain($form_values['calendar_empty_arg']));
  foreach ($form_values as $value_name => $value) {
  	switch ($value_name) {
  		case 'calendar_time_format':
        variable_set('calendar_time_format_'. $view_name,  $value);
        break;
  		case 'year':
  		case 'month':
  		case 'week':
  		case 'day':
  		case 'block':
  			$display_format[$value_name] = $value;
  			break;
    }
  }
  variable_set('calendar_display_format_'. $view_name, $display_format);
}

/**
 * create a stripe id from a combination of the field and content types
 * and store value for legend
 * formula tries to create a unique id for each possible combination
 *
 * @param $node - the node object
 * @param $query_name - the views queryname for this date field
 * @param $delta - the delta for this field, used to distinguish fields that appear more than once in the calendar
 * @param $label - the label to give this stripe.
 */
function calendar_node_stripe($view, $node, $query_name, $delta, $stripe = NULL, $label = '') {
  $type_names = node_get_types('names');
  if (!$label) {
    $label = $view->field[$delta]['label'] .' ('. $type_names[$node->type] .')';
  }
  if (!$stripe) {
    $i = 1;
    foreach ($type_names as $k => $v) {
      if ($k == $node->type) {
        break;
      }
      $i++;
    }
    $stripe = intval((20 * $delta) + $i);
  }
  $GLOBALS['calendar_stripe_labels'][$stripe] = $label;
  return $stripe;
}