<?php

/**
 * @file
 * GCal Events Module
 * Show upcoming events from a google calendar XML feed in blocks
 *
 * @author Jeff Simpson
 *
 * Adapted from: http://james.cridland.net/code/google-calendar.html
 *
 * TODO: Customizable number of days ahead to look
 */

/*
 * PHP Version Compatibility Check. Timezone support requires PHP 5.1 or higher.
 */
if (version_compare(PHP_VERSION, "5.1", ">=")) {
  define('USE_TIMEZONES', 1);
}
else {
  define('USE_TIMEZONES', 0);
}

/*
 * Configuration Defaults
 */
define('GCAL_EVENTS_DEFAULT_TEMPLATE_EVENT', '<P>#TITLE##LOC##DATE##TIME#');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_TITLE', '<b>#TITLE#</b><br />');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_DATE', '#DATE#<br />');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_TIME', '#TIME#<br />');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_ENDTIME', '#ENDTIME#');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_DESC', '#DESC#<br />');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_LOC', '#LOC#');
define('GCAL_EVENTS_DEFAULT_TEMPLATE_URL', '#URL#');
define('GCAL_EVENTS_DEFAULT_TIME_FORMAT', 'g:ia');
define('GCAL_EVENTS_DEFAULT_DATE_FORMAT', 'j F, Y');
define('GCAL_EVENTS_DEFAULT_NUM_BLOCKS', 1);
define('GCAL_EVENTS_DEFAULT_ITEM_LIST', TRUE);
define('GCAL_EVENTS_DEFAULT_NUM_EVENTS', 5);
define('GCAL_EVENTS_DEFAULT_CACHE', file_directory_path() ."/gcal_events/cache");
define('GCAL_EVENTS_DEFAULT_CACHE_DURATION', 3600);
define('GCAL_EVENTS_DEFAULT_FOOTER', '');
define('GCAL_EVENTS_DEFAULT_INPUT_FORMAT', '1');
define('GCAL_EVENTS_DEFAULT_TODAY_ONLY', '0');

define('GCAL_EVENTS_DEFAULT_HEADING_TODAY', '<b>Today</b><hr />');
define('GCAL_EVENTS_DEFAULT_HEADING_TOMORROW', '<b>Tomorrow</b><hr />');
define('GCAL_EVENTS_DEFAULT_HEADING_THISWEEK', '<b>This Week</b><hr />');
define('GCAL_EVENTS_DEFAULT_HEADING_THISMONTH', '<b>This Month</b><hr />');
define('GCAL_EVENTS_DEFAULT_HEADING_OTHER', '<b>Other</b><hr />');

if (USE_TIMEZONES) {
  define('GCAL_EVENTS_DEFAULT_TIMEZONE', date_default_timezone_get());
}

/*
 * administration settings panel
 */
function gcal_events_admin() {
  // Only Admin Allowed
  if (!user_access("access administration pages")) {
    drupal_set_message('You do not have sufficient permissions to access this page', 'error');
    return;
  }

// Set the number of blocks available for use
  $form['gcal_events_num_blocks'] = array(
    '#type' => 'textfield',
    '#title' => 'Number of blocks',
    '#size' => 5,
    '#default_value' => variable_get('gcal_events_num_blocks', GCAL_EVENTS_DEFAULT_NUM_BLOCKS),
    '#description' => 'The number of event blocks to enable',
    '#required' => TRUE
    );

  $form['cache'] = array(
    '#type' => 'fieldset',
    '#title' => t('Caching'),
    '#collapsible' => TRUE
  );

  // Set the cache directory
  $form['cache']['gcal_events_cache'] = array(
    '#type' => 'textfield',
    '#title' => t('Cache Directory'),
    '#default_value' => variable_get('gcal_events_cache', GCAL_EVENTS_DEFAULT_CACHE),
    '#description' => t('Cache directory for xml files. Must be writeable by webserver. Leave blank for no caching (not recommended!)')
  );

  $form['cache']['gcal_events_cache_duration'] = array(
    '#type' => 'textfield',
    '#title' => t('Cache Duration'),
    '#size' => 5,
    '#default_value' => variable_get('gcal_events_cache_duration', GCAL_EVENTS_DEFAULT_CACHE_DURATION),
    '#description' => t('Cache duration in seconds. Set to zero to disable caching (not recommended!)')
  );

  $form['datetime'] = array(
    '#type' => 'fieldset',
    '#title' => 'Date/Time',
    '#collapsible' => TRUE,
    '#description' => t('The format to display the time/date on the event blocks. The default date format is j F Y, which corresponds to 10 March, 2008. The default time format is g:ia, which corresponds to 12:15am. See the <a href="http://www.php.net/date">PHP Date Reference</A> for details')
    );

  // Set the date format to be used for display
  $form['datetime']['gcal_events_dateformat'] = array(
    '#type' => 'textfield',
    '#title' => 'Date Format',
    '#size' => 10,
    '#default_value' => variable_get('gcal_events_dateformat', GCAL_EVENTS_DEFAULT_DATE_FORMAT),
    '#required' => TRUE
    );

  // Set the time format to be used for display  
  $form['datetime']['gcal_events_timeformat'] = array(
    '#type' => 'textfield',
    '#title' => 'Time Format',
    '#size' => 10,
    '#default_value' => variable_get('gcal_events_timeformat', GCAL_EVENTS_DEFAULT_TIME_FORMAT),
    '#required' => TRUE
    );

  // Timezone selection.
  if (USE_TIMEZONES) {
    $form['datetime']['gcal_events_timezone'] = array(
      '#type' => 'textfield',
      '#title' => 'Timezone',
      '#size' => 30,
      '#default_value' => variable_get('gcal_events_timezone', GCAL_EVENTS_DEFAULT_TIMEZONE),
      '#description' => 'The Timezone to use. See the <a href="http://us.php.net/manual/en/timezones.php">List of Supported Timezones</A>.',
      '#required' => TRUE
      );
  }

  $form['day_grouping'] = array(
    '#type' => 'fieldset',
    '#title' => 'Day Grouping',
    '#collapsible' => TRUE,
    '#description' => t('This section deals with grouping events by days "Today", "Tomorrow", "This Week", "This Month" and "Other", by default.')
    );

  // Enable day grouping
  $form['day_grouping']['gcal_events_day_grouping'] = array(
    '#type' => 'checkbox',
    '#title' => 'Enable Day Grouping',
    '#default_value' => variable_get('gcal_events_day_grouping', FALSE),
    '#description' => t('Enable grouping events by day ("Today", "Tomorrow", "This Week", "This Month" and "Other"')
    );
  $form['day_grouping']['gcal_events_heading_today'] = array(
    '#type' => 'textfield',
    '#title' => t('Heading for Todays Events'),
    '#default_value' => variable_get('gcal_events_heading_today', GCAL_EVENTS_DEFAULT_HEADING_TODAY),
    '#description' => t('The heading to display before a day grouping for todays events.')
    );
  $form['day_grouping']['gcal_events_heading_tomorrow'] = array(
    '#type' => 'textfield',
    '#title' => t('Heading for Tomorrows Events'),
    '#default_value' => variable_get('gcal_events_heading_tomorrow', GCAL_EVENTS_DEFAULT_HEADING_TOMORROW),
    '#description' => t('The heading to display before a day grouping for tomorrows events.')
    );
  $form['day_grouping']['gcal_events_heading_thisweek'] = array(
    '#type' => 'textfield',
    '#title' => t('Heading for This Weeks Events'),
    '#default_value' => variable_get('gcal_events_heading_thisweek', GCAL_EVENTS_DEFAULT_HEADING_THISWEEK),
    '#description' => t('The heading to display before a day grouping for this weeks events.')
    );
  $form['day_grouping']['gcal_events_heading_thismonth'] = array(
    '#type' => 'textfield',
    '#title' => t('Heading for This Months Events'),
    '#default_value' => variable_get('gcal_events_heading_thismonth', GCAL_EVENTS_DEFAULT_HEADING_THISMONTH),
    '#description' => t('The heading to display before a day grouping for this months events.')
    );
  $form['day_grouping']['gcal_events_heading_other'] = array(
    '#type' => 'textfield',
    '#title' => t('Heading for other Events'),
    '#default_value' => variable_get('gcal_events_heading_other', GCAL_EVENTS_DEFAULT_HEADING_OTHER),
    '#description' => t('The heading to display before a day grouping for events that are not this month.')
    );

  // Get input formats and reorder into a useful manner
  $input_formats = filter_formats();
  foreach ($input_formats as $key=>$value) {    
    $input_formats[$key] = $value->name;
  }

  // Input format to use
  $form['gcal_events_input_format'] = array(
    '#type' => 'select',
    '#title' => t('Input Format'),
    '#options' => $input_formats,
    '#default_value' => variable_get('gcal_events_input_format', GCAL_EVENTS_DEFAULT_INPUT_FORMAT)
    );

 // Turn on debugging mode
  $form['gcal_events_debug'] = array(
    '#type' => 'select',
    '#title' => t('Debug Level'),
    '#options' => array(0=>"0 - none",1=>"1 - low",2,3,4,5=>"5 - high"),
    '#default_value' => variable_get('gcal_events_debug', 0),
    '#description' => 'Enable debugging mode level. Select 0 for no debugging.'
    );

 // Use templated "Item List"
  $form['gcal_events_item_list'] = array(
    '#type' => 'checkbox',
    '#title' => 'Item List',
    '#default_value' => variable_get('gcal_events_item_list', GCAL_EVENTS_DEFAULT_ITEM_LIST),
    '#description' => 'Use unordered list with class gcal_events for event lists. If unchecked, it will just include the exact text as specified in the templates'
    );

  return system_settings_form($form);
}

/*
 * Validate the admin settings form. Check to make sure number of blocks is positive. Time/Date formats are hard to check....so we just don't.
 */
function gcal_events_admin_validate($form, &$form_state) {
  $cache = $form_state['values']['gcal_events_cache'];

  if (strlen($cache)>0) {
    if (!file_exists($cache)) {
      if (!mkdir($cache)) {
        form_set_error('gcal_events_cache', t('Cache Directory "%path" does not exist. Please create it before saving the settings.', array('%path' => $cache)));
      }
      else {
        drupal_set_message(t("Cache directory created at %path.", array('%path' => $cache)));
      }
    }
    if (!is_dir($cache)) {
      form_set_error('gcal_events_cache', t('Cache directory "%path" is not a directory!', array('%path' => $cache)));
    }
    if (!is_writeable($cache)) {
      form_set_error('gcal_events_cache', t('Cache directory "%path" is not writeable', array('%path' => $cache)));
    }
  }

  if (USE_TIMEZONES) {
    $timezone = $form_state['values']['gcal_events_timezone'];
    if (!date_default_timezone_set($timezone)) {
      form_set_error('gcal_events_timezone', t('Timezone is not valid'));
    }
  }

  // Make sure this is last
  $num_blocks = $form_state['values']['gcal_events_num_blocks'];
  if (!is_numeric($num_blocks)) {
    form_set_error('gcal_events_num_blocks', t('You must select a number for the number of blocks.'));
  }
  else if ($num_blocks <= 0) {
    form_set_error('gcal_events_num_blocks', t('Number of blocks must be positive.'));
  }

  $old_num_blocks = variable_get('gcal_events_num_blocks', GCAL_EVENTS_DEFAULT_NUM_BLOCKS);
  if ($old_num_blocks > $num_blocks)
  {
    for ($a = $num_blocks; $a < $old_num_blocks; $a++) {
      drupal_set_message("Deleting block ". ($a+1) ." [". variable_get('gcal_events_admin_name_'. $a, 'not named') ."]");
      gcal_events_delete_block($a);
    }
  }
  return TRUE;
}

/*
 * Add the gcal events admin settings panel to the admin panel
 */
function gcal_events_menu() {
  $items = array();

  $items['admin/settings/gcal_events'] = array(
    'title' => 'GCal Events module settings',
    'description' => 'Configure settings for google calendar upcoming event blocks, including the cache directory, number of blocks, and date/time formats',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('gcal_events_admin'),
    'access arguments' => array('access administration pages'),
    'type' => MENU_NORMAL_ITEM,
   );

  return $items;
}

function gcal_events_admin_name_validate($element) {

  form_set_error('gcal_events_admin_name', 'Admin name not funny enough');
}


/** Implementation of hook_theme()
 * New registration function introduced in Drupal 6
 *
 * @return array
 */
function gcal_events_theme() {
  return array(
    'gcal_events_contents' => array(
      'arguments' => array('gcal_events' => NULL)
    )
  );
}

/**
 * Implementation of hook_block().
 *
 * This hook both declares to Drupal what blocks are provided by the module, and
 * generates the contents of the blocks themselves.
 */
function gcal_events_block($op = 'list', $delta = 0, $edit = array()) {
  // The $op parameter determines what piece of information is being requested.

  switch ($op) {
    case 'list':
      $blocks = array();

      // If $op is "list", we just need to return a list of block descriptions.
      // This is used to provide a list of possible blocks to the administrator,
      // end users will not see these descriptions.

      for ($index=0; $index<variable_get('gcal_events_num_blocks', GCAL_EVENTS_DEFAULT_NUM_BLOCKS); $index++) {
        $blocks[$index]['info'] = t('GCal Events ['. variable_get('gcal_events_admin_name_'. $index, 'Block '. ($index+1)) .']');
      }
      return $blocks;

    case 'configure':
      // If $op is "configure", we need to provide the administrator with a
      // configuration form. The $delta parameter tells us which block is being
      // configured. In this example, we'll allow the administrator to customize
      // the text of the first block.
      $form = array();

      $form['gcal_events_block'] = array(
        '#type' => 'hidden',
        '#default_value' => $delta
      );

      $form['gcal_events_admin_name'] = array(
        '#type' => 'textfield',
        '#title' => t('Admin Name'),
        '#size' => 40,
        '#description' => t('An optional short name for this block. This will only be seen in the admin panel to differentiate between calendars when sorting blocks.'),
        '#default_value' => variable_get('gcal_events_admin_name_'. $delta, 'Block '. ($delta+1)),
      );
   
      $form['calendar'] = array(
        '#type' => 'fieldset',
        '#title' => t('Calendar Settings'),
        '#collapsible' => TRUE
      );
      
      $form['calendar']['gcal_events_developer_id'] = array(
        '#type' => 'textfield',
        '#title' => t('Developer ID'),
        '#size' => 60,
        '#maxlength' => 300,
        '#description' => t('The Developer ID to use when obtaining events for this calendar. See the <a href="@google_calendar">Google Calendar API</a> for more information.', array('@google_calendar' => 'https://developers.google.com/google-apps/calendar/')),
        '#default_value' => variable_get('gcal_events_developer_id_' . $delta,  ''),
        '#required' => TRUE,
      );

      $form['calendar']['gcal_events_calendar_id'] = array(
        '#type' => 'textarea',
        '#title' => t('Calendar ID(s)'),
        '#size' => 60,
        '#maxlength' => 1000,
        '#description' => t('Calendar IDs, as shown on Calendar Settings page in google calendar. Will be in the form something@group.calendar.google.com, 
someting@gmail.com, etc. Multiple Calendar IDs can be separated by space or return.'),
        '#default_value' => variable_get('gcal_events_calendar_id_'. $delta,  '')
      );

      $form['calendar']['gcal_events_private_id'] = array(
        '#type' => 'textfield',
        '#title' => t('Private ID'),
        '#size' => 60,
        '#maxlength' => 300,
        '#description' => t('To use a private calendar, include the Private ID here. The Private ID will be part of the Private XML address that looks like 
private-XXXXXXXXXXXXX/basic. Include only the string after private- but before /basic. Leave this field blank to use the public calendar. Note: You still must include 
Calendar ID, even if you are using a private calendar. You can also put the entire private xml address in here and the private ID will be parsed out. Using multiple 
private calendars will not work.'),
        '#default_value' => variable_get('gcal_events_private_id_'. $delta, '')
      );

      $form['calendar']['gcal_events_num_events'] = array(
        '#type' => 'textfield',
        '#title' => t('Number of Events'),
        '#size' => 5,
        '#description' => t('The number of upcoming events to display in this block'),
        '#default_value' => variable_get('gcal_events_num_events_'. $delta, GCAL_EVENTS_DEFAULT_NUM_EVENTS)
      );

      $form['calendar']['gcal_events_today_only'] = array(
        '#type' => 'checkbox',
        '#title' => t('Show events from today only'),
        '#description' => t('Show only events from this calendar day, (not events in the next 24 hours)'),
        '#default_value' => variable_get('gcal_events_today_only_'. $delta, GCAL_EVENTS_DEFAULT_TODAY_ONLY)
      );

      $form['datetime'] = array(
        '#type' => 'fieldset',
        '#title' => 'Date/Time',
        '#collapsible' => TRUE,
        '#description' => t('The format to display the time/date on the event blocks. Default is j F Y, which corresponds to 10 March, 2008. See the <a href="http://www.php.net/date">PHP Date Reference</A> for details')
      );

      $form['datetime']['gcal_events_dateformat'] = array(
        '#type' => 'textfield',
        '#title' => t('Date Format'),
        '#description' => t('Date format to use for this block. Leave blank for default.'),
        '#default_value' => variable_get('gcal_events_dateformat_'. $delta, "")
      );

      $form['datetime']['gcal_events_timeformat'] = array(
        '#type' => 'textfield',
        '#title' => t('Time Format'),
        '#description' => t('Time format to use for this block. Leave blank for default.'),
        '#default_value' => variable_get('gcal_events_timeformat_'. $delta, "")
      );

      $form['template'] = array(
        '#type' => 'fieldset',
        '#title' => t('Templates'),
        '#collapsible' => TRUE,
        '#description' => t('These are the templates to use. Variables #TITLE#, #DESC#, #DATE#, #TIME#, #ENDTIME#, #LOC#, #URL#, and #LOCURL# are availble for use. It is recommended to only use multiple variables inside the event template.')
      );

      $form['template']['gcal_events_template_event'] = array(
        '#type' => 'textarea',
        '#title' => 'Event Template',
        '#rows' => 5,
        '#cols' => 20,
        '#description' => t('Use the variables #TITLE#, #DESC#, #DATE#, #TIME#, #ENDTIME#, #LOC#, #URL#, to insert values. These values are generated by the templates that follow.'),
        '#default_value' => variable_get('gcal_events_template_event_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_EVENT)
      );
      
      $form['template']['gcal_events_template_title'] = array(
        '#type' => 'textfield',
        '#title' => 'Title Template (#TITLE#)',
        '#description' => t('Use #TITLE# to insert the title.'),
        '#default_value' => variable_get('gcal_events_template_title_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_TITLE)
      );
      
      $form['template']['gcal_events_template_desc'] = array(
        '#type' => 'textfield',
        '#title' => 'Description Template (#DESC#)',
        '#description' => t('Use #DESC# to insert the description.'),
        '#default_value' => variable_get('gcal_events_template_desc_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_DESC)
      );

      $form['template']['gcal_events_template_date'] = array(
        '#type' => 'textfield',
        '#title' => 'Date Template (#DATE#)',
        '#description' => t('Use #DATE# to insert the date.'),
        '#default_value' => variable_get('gcal_events_template_date_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_DATE)
      );
      
      $form['template']['gcal_events_template_time'] = array(
        '#type' => 'textfield',
        '#title' => 'Time Template (#TIME#)',
        '#description' => t('Use #TIME# to insert the time.'),
        '#default_value' => variable_get('gcal_events_template_time_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_TIME)
      );
      
      $form['template']['gcal_events_template_loc'] = array(
        '#type' => 'textfield',
        '#title' => 'Location Template (#LOC#)',
        '#description' => t('Use #LOC# to insert the location.'),
        '#default_value' => variable_get('gcal_events_template_loc_'. $delta, GCAL_EVENTS_DEFAULT_TEMPLATE_LOC)
      );

      $form['text'] = array(
        '#type' => 'fieldset',
        '#title' => 'Custom Text',
        '#collapsible' => TRUE
      );

      $form['text']['gcal_events_empty'] = array(
        '#type' => 'textarea',
        '#title' => t('No Events'),
        '#description' => t('Text to display when there are no events to list. Leaving this blank will result in the block not appearing when there are no events.'),
        '#default_value' => variable_get('gcal_events_empty_'. $delta, 'none')
      );

      $form['text']['gcal_events_header'] = array(
        '#type' => 'textarea',
        '#title' => t('Header'),
        '#description' => t('Text to display at the top of this event list.'),
        '#default_value' => variable_get('gcal_events_header_'. $delta, ''),
      );
      
      $form['text']['gcal_events_footer'] = array(
        '#type' => 'textarea',
        '#title' => t('Footer'),
        '#description' => t('Text to display at the bottom of this event list. Typically contains a link to the source for the calendar.'),
        '#default_value' => variable_get('gcal_events_footer_'. $delta, '')
      );

      $form['gcal_events_reset'] = array(
        '#type' => 'button',
        '#value' => t('Reset to defaults'),
        '#executes_submit_callback' => TRUE,
        '#submit' => array('block_reset_defaults')
      );

      return $form;

    case 'save':
      // If $op is "save", we need to save settings from the configuration form.
      // Since the first block is the only one that allows configuration, we
      // need to check $delta to make sure we only save it.

      // Have Drupal save the string to the database.
      $calendar_id = check_plain($edit['gcal_events_calendar_id']);

      //if (preg_match_all('#feeds/(\S+)/public#', $calendar_id, $temp_calendar_id)) {
      //  $calendar_id = $temp_calendar_id[1][0];
      //}

      variable_set('gcal_events_calendar_id_'. $delta, $calendar_id);
      
      variable_set('gcal_events_developer_id_' . $delta, check_plain($edit['gcal_events_developer_id']));

      $private_id = check_plain($edit['gcal_events_private_id']);
      if (preg_match_all('#private-(\S+)/basic#', $private_id, $temp_private_id)) {
        $private_id = $temp_private_id[1][0];
      }
      variable_set('gcal_events_private_id_'. $delta, $private_id);

      // error check
      if ($edit['gcal_events_num_events'] > 0) {
        variable_set('gcal_events_num_events_'. $delta, check_plain($edit['gcal_events_num_events']));
      }

      variable_set('gcal_events_today_only_'. $delta, $edit['gcal_events_today_only']);
      variable_set('gcal_events_empty_'. $delta, $edit['gcal_events_empty']);
      variable_set('gcal_events_header_'. $delta, $edit['gcal_events_header']);
      variable_set('gcal_events_footer_'. $delta, $edit['gcal_events_footer']);
      variable_set('gcal_events_admin_name_'. $delta, check_plain($edit['gcal_events_admin_name']));
      variable_set('gcal_events_template_event_'. $delta, $edit['gcal_events_template_event'], 'gcal_events' );
      variable_set('gcal_events_template_title_'. $delta, $edit['gcal_events_template_title']);
      variable_set('gcal_events_template_desc_'. $delta, $edit['gcal_events_template_desc']);
      variable_set('gcal_events_template_time_'. $delta, $edit['gcal_events_template_time']);
      variable_set('gcal_events_template_date_'. $delta, $edit['gcal_events_template_date']);
      variable_set('gcal_events_template_loc_'. $delta, $edit['gcal_events_template_loc']);

      variable_set('gcal_events_timeformat_'. $delta, check_plain($edit['gcal_events_timeformat']));
      variable_set('gcal_events_dateformat_'. $delta, check_plain($edit['gcal_events_dateformat']));

      return;
    case 'view': default:
      // If $op is "view", then we need to generate the block for display
      // purposes. The $delta parameter tells us which block is being requested.

      $block['subject'] = t('Calendar '. ($delta+1));
      $block['content'] = gcal_events_contents($delta);

      return $block;
  }
}

function block_reset_defaults($form, &$form_state) {
  // Deletes all the variables for this block, resetting them to their defaults

  $block_number = check_plain($form_state['values']['gcal_events_block']);
  //print "This is block number [".$block_number."]";
  drupal_set_message('Reset to defaults');

  gcal_events_delete_block($block_number);
}

function gcal_events_delete_block($block_number) {
  variable_del('gcal_events_today_only_'. $block_number);
  variable_del('gcal_events_header_'. $block_number);
  variable_del('gcal_events_footer_'. $block_number);
  variable_del('gcal_events_admin_name_'. $block_number);
  variable_del('gcal_events_developer_id_'. $block_number);
  variable_del('gcal_events_calendar_id_'. $block_number);
  variable_del('gcal_events_private_id_'. $block_number);
  variable_del('gcal_events_num_events_'. $block_number);
  variable_del('gcal_events_dateformat_'. $block_number);
  variable_del('gcal_events_timeformat_'. $block_number);
  variable_del('gcal_events_template_event_'. $block_number);
  variable_del('gcal_events_template_title_'. $block_number);
  variable_del('gcal_events_template_desc_'. $block_number);
  variable_del('gcal_events_template_date_'. $block_number);
  variable_del('gcal_events_template_time_'. $block_number);
  variable_del('gcal_events_template_loc_'. $block_number);
  variable_del('gcal_events_empty_'. $block_number);
  variable_del('gcal_events_header_'. $block_number);
  variable_del('gcal_events_footer_'. $block_number);
}

/**
 * A block content function.
 */
function gcal_events_get_events($which_block) {

  // for timing
  $start_time = microtime(true);

  gcal_events_debug_2("PHP Memory Limit: ". ini_get('memory_limit'));
  gcal_events_debug("PHP Initial Memory Usage: ". round(memory_get_usage(FALSE)/1024/1024, 1 ) ."MB");
  gcal_events_debug("PHP Initial Memory Usage (real): ". round(memory_get_usage(TRUE)/1024/1024, 1 ) ."MB");

  $gcal_events = array();

  $developer_id = variable_get('gcal_events_developer_id_' . $which_block, '');
  $private_id = variable_get('gcal_events_private_id_'. $which_block, '');
  $calendar_id = variable_get('gcal_events_calendar_id_'. $which_block, '');
  $today_only = variable_get('gcal_events_today_only_'. $which_block, '');
  $max_results = variable_get('gcal_events_num_events_' . $which_block, GCAL_EVENTS_DEFAULT_NUM_EVENTS);

  $dateformat = variable_get('gcal_events_dateformat_'. $which_block, "");
  if ($dateformat == "") {
    $dateformat = variable_get('gcal_events_dateformat', GCAL_EVENTS_DEFAULT_DATE_FORMAT);
  }
  
  $timeformat = variable_get('gcal_events_timeformat_' . $which_block, '');
  if ($timeformat == "") {
    $timeformat = variable_get('gcal_events_timeformat', GCAL_EVENTS_DEFAULT_TIME_FORMAT);
  }

  $admin_name = variable_get('gcal_events_admin_name_' . $which_block, 'Block '. ($which_block+1));

  if ($calendar_id == "") {
    drupal_set_message('GCal Events['. $admin_name .'] Calendar ID Not Set!', 'error');
    return;
  }

  if (USE_TIMEZONES) { 
    gcal_events_debug('Timezone: '. date_default_timezone_get());
    $timezone = variable_get('gcal_events_timezone', GCAL_EVENTS_DEFAULT_TIMEZONE);
    if (!date_default_timezone_set($timezone)) {
      drupal_set_message('GCal Events: Timezone $timezone is not valid!');
    }
  }
  else {
    gcal_events_debug('Timezone Support Disabled! PHP Version '. PHP_VERSION .' < 5.1');
  }  

  // Including the google-api-php-client library (required).
  $autoload_path = libraries_get_path('google-api-php-client') . '/autoload.php';
  if (!file_exists($autoload_path)) {
    drupal_set_message('GCal Events: The google-api-php-client library was not found.', 'error');
    return;
  }

  include_once($autoload_path);

  // https://developers.google.com/google-apps/calendar/v3/reference
  $client = new Google_Client();
  $client->setApplicationName('gcal_events_feed');
  $client->setDeveloperKey($developer_id);

  $service = new Google_Service_Calendar($client);
  $optParams = array(
    'orderBy' => 'startTime',
    'singleEvents' => 'true',
    'timeMin' => date('Y-m-d') . 'T00:00:00' . date('P'),
    'timeZone' => $timezone,
  );
  
  if ($today_only) {
    $optParams['timeMax'] = date('Y-m-d') . 'T23:59:00' . date('P');
  }

  $events = array();
  
  try {
    $events = $service->events->listEvents($calendar_id, $optParams);
  }
  catch (Exception $e) {
    drupal_set_message(t('GCal Events: Bad call to list events'), 'error');
    return;
  }

  $count = 0;

  foreach ($events->getItems() as $event) {
    if ($count >= $max_results) {
      break;
    }
    
    $event_id = $event->getId();
    $event = $service->events->get($calendar_id, $event_id);

    $title = trim($event->getSummary());
    $description = $event->getDescription();
    $location = $event->getLocation();
    $status = $event->getStatus();

    $start = $event->getStart();
    $end = $event->getEnd();
    $allday = !empty($start->date);
    $date = !empty($start->date) ? $start->date : $start->dateTime;
    $gcal_time = !empty($start->dateTime) ? format_date($start->dateTime, 'custom', $timeformat) : '';
    $gcal_endtime = !empty($end->dateTime) ? format_date($end->dateTime, 'custom', $timeformat) : '';
    $unixdate = strtotime($date);

    if (strlen($title) > 1 && $status != 'canceled' && strlen($date) > 0) {
      $temp[] = array(
        'title' => $title,
        'description' => $description,
        'allday' => $allday,
        'where' => $location,
        'date' => format_date($unixdate, 'custom', $dateformat),
        'timestamp' => $unixdate,
        'time' => $gcal_time,
        'endtime' => $gcal_endtime,
        'link' => '', // TODO
        'today' => date("Y-m-d") == date("Y-m-d", $unixdate),
        'tomorrow' => (date("Y-m-d",strtotime("+1 day")) == date("Y-m-d", $unixdate)),
        'thisweek' => (date("Y-W") == date("Y-W", $unixdate)),
        'thismonth' => (date("Y-m") == date("Y-m", $unixdate)),
      );
    }
    $count++;
  }

  gcal_events_debug("PHP Memory Usage: ". round(memory_get_usage(FALSE)/1024/1024, 1 ) ."MB");
  gcal_events_debug("PHP Memory Usage (real): ". round(memory_get_usage(TRUE)/1024/1024, 1 ) ."MB");
  gcal_events_debug_block($admin_name, 'Feed processing took ' . round((microtime(true) - $time_feed_process),2) . ' seconds');

  return $temp;
}

function template_events($events, $which_block) {
  foreach ($events as $item) {

    // Now, let's run it through some str_replaces, and store it with the date for easy sorting later
    $temp_event=variable_get('gcal_events_template_event_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_EVENT);

    if ($item['title']) {
      $temp_event=str_replace("#TITLE#", $item['title'], str_replace("#TITLE#", variable_get('gcal_events_template_title_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_TITLE), $temp_event));
    }
    else {
      $temp_event=str_replace("#TITLE#", "", $temp_event);
    }

    if ($item['description']) {
      $temp_event=str_replace("#DESC#", $item['description'], str_replace("#DESC#", variable_get('gcal_events_template_desc_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_DESC), $temp_event));
    }
    else {
      $temp_event=str_replace("#DESC#", "", $temp_event);
    }

    if ($item['date']) {
      $temp_event=str_replace("#DATE#", $item['date'], str_replace("#DATE#", variable_get('gcal_events_template_date_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_DATE), $temp_event));
    }
    else {
      $temp_event=str_replace("#DATE#", "", $temp_event);
    }

    if ($item['time']) {
      $temp_event=str_replace("#TIME#", $item['time'], str_replace("#TIME#", variable_get('gcal_events_template_time_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_TIME), $temp_event));
    }
    else {
      $temp_event=str_replace("#TIME#", "", $temp_event);
    }

    if ($item['endtime']) {
      $temp_event=str_replace("#ENDTIME#", $item['endtime'], str_replace("#ENDTIME#", GCAL_EVENTS_DEFAULT_TEMPLATE_ENDTIME, $temp_event));
    }
    else {
      $temp_event=str_replace("#ENDTIME#", "", $temp_event);
    }

   if ($item['where']) {
      $temp_event=str_replace("#LOC#", $item['where'], str_replace("#LOC#", variable_get('gcal_events_template_loc_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_LOC), $temp_event));
      $temp_event=str_replace("#LOCURL#", urlencode($item['where']), $temp_event);
    }
    else {
      $temp_event=str_replace("#LOC#", "", $temp_event);
    }

    if ($item['link']) {
      $temp_event=str_replace("#URL#", $item['link'], str_replace("#URL#", variable_get('gcal_events_template_url_'. $which_block, GCAL_EVENTS_DEFAULT_TEMPLATE_URL), $temp_event));
    }
    else {
      $temp_event=str_replace("#URL#", "", $temp_event);
    }

    $input_format = variable_get('gcal_events_input_format', GCAL_EVENTS_DEFAULT_INPUT_FORMAT);
    if (!filter_access($input_format)) {
      drupal_set_message('Input Format ' . $input_format . ' is not accessible by the current user');
      return "Error: Input format is not accessible";
    }

    // Check for invalid html
    $temp_event = check_markup($temp_event, $input_format, FALSE);

    $item['event'] = $temp_event;
    $gcal_events[] = $item;
}
  return $gcal_events;
}

function gcal_events_contents($which_block) {

  $events = gcal_events_get_events($which_block);
  $events = template_events($events, $which_block);

  return theme('gcal_events_contents', $events, $which_block);
}

function theme_gcal_events_contents($gcal_events, $which_block) {
  $full_path = drupal_get_path('module', 'gcal_events'). '/gcal_events.css';
  drupal_add_css($full_path);

  $output = "";
  
  $output .= variable_get('gcal_events_header_'. $which_block, '');

  $use_item_list = variable_get('gcal_events_item_list', '1');

  $day_grouping = variable_get('gcal_events_day_grouping', FALSE);

  if (empty($gcal_events)) {
    $output .= variable_get('gcal_events_empty_'. $which_block, 'none');
    return $output;
  }

  if ($day_grouping) {
    $today_events = array_filter($gcal_events, 'is_today');
    $tomorrow_events = array_filter($gcal_events, 'is_tomorrow');
    $thisweek_events = array_filter($gcal_events, 'is_thisweek_exc');
    $thismonth_events = array_filter($gcal_events, 'is_thismonth_exc');
    $other_events = array_filter($gcal_events, 'isnt_thismonth');

    if (count($today_events)>0) {
      $output .= variable_get('gcal_events_heading_today', GCAL_EVENTS_DEFAULT_HEADING_TODAY);
      $output .= gcal_events_display_events($use_item_list, $today_events, 'today');
    }
    if (count($tomorrow_events)>0) {
      $output .= variable_get('gcal_events_heading_tomorrow', GCAL_EVENTS_DEFAULT_HEADING_TOMORROW);
      $output .= gcal_events_display_events($use_item_list, $tomorrow_events, 'tomorrow');
    }
    if (count($thisweek_events)>0) {
      $output .= variable_get('gcal_events_heading_thisweek', GCAL_EVENTS_DEFAULT_HEADING_THISWEEK);
      $output .= gcal_events_display_events($use_item_list, $thisweek_events, 'thisweek');
    }
    if (count($thismonth_events) > 0) {
      $output .= variable_get('gcal_events_heading_thismonth', GCAL_EVENTS_DEFAULT_HEADING_THISMONTH);
      $output .= gcal_events_display_events($use_item_list, $thismonth_events, 'thismonth');
    }
    if (count($other_events)>0) {
      $output .= variable_get('gcal_events_heading_other', GCAL_EVENTS_DEFAULT_HEADING_OTHER);
      $output .= gcal_events_display_events($use_item_list, $other_events, 'other');
    }
 }
  else {
    $output .= gcal_events_display_events($use_item_list, $gcal_events);
  }
  $output .= variable_get('gcal_events_footer_'. $which_block, '');

  return $output;
}

function gcal_events_display_events($use_item_list, $events, $class='gcal_events') {
  if ($class != "gcal_events") {
    $class = "gcal_events_" . $class;
  }
  if ($use_item_list) {
    return theme('item_list', gcal_events_just_entries($events), NULL, 'ul', array('class' => $class));
  }
  else {
    return join("", gcal_events_just_entries($events));
  }
}

function is_today($event) {
  if ($event['today']) return TRUE;
  return FALSE;
}

function is_tomorrow($event) {
  if ($event['tomorrow']) return TRUE;
  return FALSE;
}

function is_thisweek_inc($event) {
  if ($event['thisweek']) return TRUE;
  return FALSE;
}

function is_thisweek_exc($event) {
  if ($event['thisweek'] && !$event['today'] && !$event['tomorrow']) return TRUE;
  return FALSE;
}

function is_thismonth_inc($event) {
  if ($event['thismonth']) return TRUE;
  return FALSE;
}
function isnt_thismonth($event) {
  return !is_thismonth_inc($event);
}

function is_thismonth_exc($event) {
  if ($event['thismonth'] && !$event['thisweek'] && !$event['tomorrow'] && !$event['today']) return TRUE;
  return FALSE;
}

function gcal_events_just_entries($events) {
  foreach ($events as $event) {
    $just_entries[] = $event['event'];
  }
  return $just_entries;
}

function gcal_events_debug($string) {
  gcal_events_debug_master(array(level=>1, msg=>$string));
}

function gcal_events_debug_2($string) {
  gcal_events_debug_master(array(level=>2, msg=>$string));
}

function gcal_events_debug_3($string) {
  gcal_events_debug_master(array(level=>3, msg=>$string));
}

function gcal_events_debug_4($string) {
  gcal_events_debug_master(array(level=>4, msg=>$string));
}

function gcal_events_debug_5($string) {
  gcal_events_debug_master(array(level=>5, msg=>$string));
}

function gcal_events_debug_block($block, $string) {
  gcal_events_debug_master(array(block=>$block, msg=>$string));
}

function gcal_events_debug_block_2($block, $string) {
  gcal_events_debug_master(array(level=>2, block=>$block, msg=>$string));
}

/*
 * Debug Message function master. It's best to call the other wrapper functions instead.
 */
function gcal_events_debug_master($data) {
  // Get the debug variable
  static $debug_mode = -1;
  if ($debug_mode == -1) {
    $debug_mode = variable_get('gcal_events_debug', FALSE);
  }
  if ($debug_mode) {
    if (is_array($data)) {
      if ($data['level'] && $data['level'] > $debug_mode) return;
      $disp_string = '';
      $disp_string .= "GCal Events";
      if ($data['block']) {  
        $disp_string .= "[". $data['block'] ."]: ";
      }
      else {
        $disp_string .= ": ";
      }
      $disp_string .= $data['msg'];
      drupal_set_message($disp_string);
    }
    else {
      drupal_set_message("gcal_events_debug_master called incorrectly!");
    }
  }
}