<?php
// $Id: calendar_block.module,v 1.4.2.1 2009/01/20 08:46:24 skilip Exp $

/**
 * @file
 * This module provides a fully customizale calendar block.
 *
 * You can set the actions for the dates by using hook_calendar_block(&$day, $op).
 */

/**
 * Implements hook_menu().
 */
function calendar_block_menu() {
  $items['calendar_block_ajax'] = array(
    'page callback' => 'calendar_block_ajax',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Implements hook_block_info().
 */
function calendar_block_block_info() {
  $blocks['calendar'] = array(
    'info' => t('Calendar'),
  );
  return $blocks;
}

/**
 * Implements hook_block_configure().
 */
function calendar_block_block_configure($delta = '') {
  // Decide whether to show the days of the week or not
  $form = array();
  if ($delta == 'calendar') {
    $form['show_weekdays'] = array(
      '#type' => 'checkbox', 
      '#title' => t('Display the days of the week'), 
      '#default_value' => variable_get('calendar_block_show_weekdays', FALSE),
      '#weight' => 5,
    );
  }
  return $form;
}

function calendar_block_block_save($delta = '', $edit = array()) {
  if ($delta == 'calendar') {
    variable_set('calendar_block_show_weekdays', $edit['show_weekdays']);
  }
}
/**
 * Implements hook_block_view().
 */
function calendar_block_block_view($delta) {
  $path = drupal_get_path('module', 'calendar_block');
  $year = isset($_GET['calendar_block_year']) ? $_GET['calendar_block_year'] : NULL;
  $month = isset($_GET['calendar_block_month']) ? $_GET['calendar_block_month'] : NULL;

  return array(
    'subject' => t('Calendar'),
    'content' => array(
      '#markup' => theme('calendar_block', array('calendar' => calendar_block_load($year, $month))),
      '#attached' => array(
        'css' => array($path . '/calendar_block.css' => array()),
      ),
    ),
  );
}

/**
 * Implements hook_theme().
 */
function calendar_block_theme() {
  return array(
    'calendar_block' => array(
      'render element' => 'elements',
      'template' => 'calendar_block',
    ),
  );
}

/**
 *
 */
function calendar_block_load($year = NULL, $month = NULL) {
  $first_day = variable_get('date_first_day', 0);
  $weekdays = array('su', 'mo', 'tu', 'we', 'th', 'fr', 'sa');
  $weekdays = array_merge(array_slice($weekdays, $first_day), array_slice($weekdays, 0, $first_day));
  $weekdays = array_combine($weekdays, $weekdays);

  $calendar = (object) array(
    'year' => $year ? (int) $year : date('Y'),
    'month' => $month ? (int) $month : date('m'),
    'weekdays' => $weekdays,
  );
  $calendar->show_weekdays = variable_get('calendar_block_show_weekdays', TRUE);

  $date = (object) array();
  // Give other modules the opportunity set the date for the calendar
  drupal_alter('calendar_block_date', $calendar, $date);

  $calendar->timestamp = ($calendar->year && $calendar->month) ? mktime(1, 1, 1, $calendar->month, 1, $calendar->year) : REQUEST_TIME;

  $weekdays = array_keys($calendar->weekdays);

  $calendar->month = date('m', $calendar->timestamp); // The numeric current month (09)
  $calendar->year = date('Y', $calendar->timestamp); // The numeric current year (2008)

  // If the month is equal to the current month, get the current day
  if (date('Y-m', $calendar->timestamp) == date('Y-m')) {
    $calendar->day = date('d', REQUEST_TIME); // The numeric current day (20)
  }

  $calendar->month_str = date('F', $calendar->timestamp); // The current month (September)
  $calendar->days_in_month = cal_days_in_month(0, $calendar->month, $calendar->year); // The number of days in this month (31)
  $calendar->first_day_of_month = drupal_substr(drupal_strtolower(date('D', mktime(0, 0, 0, $calendar->month, 1, $calendar->year))), 0, 2); // The first week day of this month (mo, tu, we ....)

  // If the first day of the month is not the same as the first day in the weekdays, set in the configuration settings,
  // we need to set the last days of the previous month first
  if ($calendar->show_weekdays) {
    if ($calendar->first_day_of_month !== $weekdays[0]) {
      $prev_month = ($calendar->month > 1) ? $calendar->month -1 : 12;
      $prev_year = ($calendar->month > 1) ? $calendar->year : $calendar->year - 1;
  
      $tmp_array = $weekdays;
      $tmp_array = array_flip($tmp_array);
      $calendar->previous_days_offset = $tmp_array[$calendar->first_day_of_month];
      $calendar->days_in_previous_month = cal_days_in_month(0, $prev_month, $prev_year);
  
      for ($i = $calendar->previous_days_offset - 1; $i > -1; $i--) {
        $calendar->dates[] = (object) array(
          'year' => $prev_year,
          'month' => intval($prev_month),
          'day' => $calendar->days_in_previous_month - $i,
        );
      }
    }
  }
  // Here we'll set the days for the month we're viewing
  for ($i = $calendar->days_in_month - 1; $i > -1; $i--) {
    $calendar->dates[] = (object) array(
      'year' => $calendar->year,
      'month' => intval($calendar->month),
      'day' => $calendar->days_in_month - $i,
    );
  }

  if ($calendar->show_weekdays) {
    // If the number of added dates is not dividable by 7, we need to add some more dates for the next month
    while ((count($calendar->dates)) / 7 < ceil(count($calendar->dates) / 7)) {
      $counter = isset($counter) ? $counter + 1 : 1;
      if (!isset($next_month)) {
        $next_month = ($calendar->month < 12) ? $calendar->month + 1 : 1;
      }
      $calendar->dates[] = (object) array(
        'year' => ($calendar->month < 12 ? $calendar->year : $calendar->year + 1),
        'month' => intval($next_month),
        'day' => $counter,
      );
    }
  }

  foreach ($calendar->dates as $i => $date) {
    $calendar->dates[$i]->timestamp = mktime(1, 1, 1, $date->month, $date->day, $date->year);
  }
  return $calendar;
}

/**
 * Theme the calendar.
 */
function calendar_block_preprocess_calendar_block(&$variables) {
  $calendar = $variables['calendar'];

  $weekdays = array_values($calendar->weekdays);

  $variables['header'] = format_date($calendar->timestamp, 'custom', 'F Y');
  $variables['prev_class'] = ($calendar->month > 1 ? ($calendar->month - 1) . '-' . $calendar->year : '12-' . ($calendar->year - 1));
  $variables['next_class'] = ($calendar->month < 12 ? ($calendar->month + 1) . '-' . $calendar->year : '01-' . ($calendar->year + 1));
  
  $next_month = ($calendar->month < 12 ? ($calendar->month + 1) : 1);
  $prev_month = ($calendar->month > 1 ? ($calendar->month - 1) : 12);
  $year_next = ($next_month == 1 ? ($calendar->year + 1) : $calendar->year);
  $year_prev = ($prev_month == 12 ? ($calendar->year - 1) : $calendar->year);

  $variables['previous_link'] = l('<', $_GET['q'], array('query' => array(
    'calendar_block_month' => $prev_month,
    'calendar_block_year' => $year_prev,
  )));
  $variables['next_link'] = l('>', $_GET['q'], array('query' => array(
    'calendar_block_month' => $next_month,
    'calendar_block_year' => $year_next,
  )));

  if ($calendar->show_weekdays) {
    // Create the weekdays row
    foreach (array_values($calendar->weekdays) as $i => $day) {
      $variables['rows_weekdays'][$i] = array(
        'data' => t($day),
        'attributes' => array('class' => array('hok', 'top', (($i == 0) ? 'first' : (($i == 6) ? 'last' : '')))),
      );
    }
  }

  $variables['rows_dates'] = array();

  foreach ($calendar->dates as $i => $date) {
    $key_row = floor(($i) / 7);
    $element = array(
      '#date' => $date,
      '#markup' => '<span>' . $date->day . '</span>',
      '#suffix' => '<div class="border_bottom"></div>',
      '#attributes' => array('class' => array('hok', format_date($date->timestamp, 'custom', 'm-j-Y'))),
    );

    if (!isset($variables['rows_dates'][$key_row])) {
      $key_column = 0;
      $variables['rows_dates'][$key_row] = array(
        'attributes' => array(
          'class' => array('week'),
          'id' => 'calendar_row' . ($key_row + 1),
        ),
      );

      if ($key_row == 0) {
        $variables['rows_dates'][$key_row]['attributes']['class'][] = 'first';
      }
      if ($key_row == (ceil(count($calendar->dates) / 7) - 1)) {
        $variables['rows_dates'][$key_row]['attributes']['class'][] = 'last';
      }
    }

    if ($key_column == 0) {
      $element['#attributes']['class'][] = 'first';
    }

    if ($key_column == 6) {
      $element['#attributes']['class'][] = 'last';
    }
    else {
      $element['#suffix'] .= '';
    }

    if ($date->month !== intval($calendar->month)) {
      $element['#attributes']['class'][] = 'disabled';
    }

    if ((isset($calendar->day) && $date->day == $calendar->day) && ($date->month == $calendar->month) && ($date->year == $calendar->year)) {
      $element['#attributes']['class'][] = 'today';
    }

    // Give other modules the opportunity to change the content for each date
    drupal_alter('calendar_block_element', $element);

    $variables['rows_dates'][$key_row]['data'][$key_column] = $element;

    $key_column++;
  }
}

/**
 * Calendar days in month
 *
 * Some PHP versions don't have cal_days_in_month(), this accounts for that.
 */
if (!function_exists('cal_days_in_month')) {
  function cal_days_in_month($calendar, $month, $year) {
    // $calendar just gets ignored, assume gregorian
    // calculate number of days in a month
    return $month == 2 ? ($year % 4 ? 28 : ($year % 100 ? 29 : ($year % 400 ? 28 : 29))) : (($month - 1) % 7 % 2 ? 30 : 31);
  }
}