<?php
// $Id$

/**
 * Implementation of hook_help().
 */
function scheduler_help($section) {
	if ($section == 'admin/modules#description') {
		return t('A module to schedule when nodes are (un)published.');
	}
}


/**
 * Implementation of hook_perm().
 */
function scheduler_perm() {
	return array('schedule (un)publishing of nodes');
}

/**
 * Implementation of hook_menu().
 */
function scheduler_menu($may_cache) {
	$items = array();
	if ($may_cache) {
		$items[] = array(
			'path' => 'scheduler/cron',
			'type' => MENU_CALLBACK,
			'callback' => '_scheduler_run_cron',
			'access' => TRUE,
		);
		$items[] = array(
			'path' => 'scheduler/timecheck',
			'type' => MENU_CALLBACK,
			'callback' => '_scheduler_timecheck',
			'access' => user_access('schedule (un)publishing of nodes'),
		);
	}
	return $items;
}

/**
 * Implementation of hook_form_alter().
 */
function scheduler_form_alter($form_id, &$form) {
	//allow scheduling on a per-node-type basis

	if ('node_type_form' == $form_id) {
		$form['workflow']['scheduler'] = array(
			'#type' => 'checkbox', 
			'#title' => t('Enable scheduled (un)publishing'), 
			'#default_value' => variable_get('scheduler_'. $form['#node_type']->type, 0),
			'#description' => t('Check this box to enable scheduled (un)publishing for this node type.')
		);
	}
	// is this a node form?
	else if (isset($form['type']['#value']) && $form['type']['#value'] .'_node_form' == $form_id) {
		if (user_access('schedule (un)publishing of nodes')) {
			// if scheduling has been enabled for this node type
			if (variable_get('scheduler_'. $form['type']['#value'], 0) == 1) {
				//use JScalendar picker for dates if the module exists and is enabled
				$jscalendar = FALSE;
				if (module_exists('jscalendar')) {
					$jscalendar = TRUE;
					// Show 24-hour clock for JScalendar
					//$form['#jscalendar_timeFormat'] = '24';
					// Use only year, month, and day in textfield.
					$form['#jscalendar_ifFormat'] = '%Y-%m-%d';
					// Don't show time.
					$form['#jscalendar_showsTime'] = 'false';
				}
				
				$node = $form['#node'];
				
				//only load the values if we are viewing an existing node
				if ($node->nid > 0) {
					$defaults = db_fetch_object(db_query('SELECT publish_on, unpublish_on, timezone FROM {scheduler} WHERE nid = %d', $node->nid));
				}
				else {
					// init standard values
					$defaults = new StdClass;
					$defaults->publish_on = $defaults->unpublish_on = NULL;
				}

				// We add the additional validation function this way to preserve any existing validation function
				$form['#validate']['_scheduler_form_validate' ] = array();

				//note don't use format_date() because drupal automatically formats the date to the user's timezone
				//this will show the wrong time because scheduler can set nodes to be published in different timezones
				$form['scheduler_settings'] = array(
					'#type' => 'fieldset',
					'#title' => t('Scheduling options'),
					'#collapsible' => TRUE,
					'#collapsed' => ($defaults->publish_on != 0 || $defaults->unpublish_on != 0) ? FALSE: FALSE,
					'#weight' => 35
				);
				
				$form['scheduler_settings']['publish_on'] = array(
					'#type' => 'textfield', 
					'#title' => t('Publish on'), 
					'#maxlength' => 25,
					//we subtract the time zone to show the user the correct time they entered
					//and below that we show the timezone to adjust this time by
					//we store the adjusted timezone value in the database for cron
					'#default_value' => $defaults->publish_on ? date('d.m.Y', $defaults->publish_on - $defaults->timezone) : date('d.m.Y'),
					'#description' => t('Format: %time. Default is set to publish now.', array('%time' => date('d.m.Y'))),
					'#attributes' => $jscalendar ? array('class' => 'jscalendar') : array(),
					// Use only year, month, and day in textfield.
//					'#jscalendar_ifFormat' => $jscalendar ? '%Y-%m-%d' : array(),
					'#jscalendar_ifFormat' => $jscalendar ? '%d.%m.%Y' : array(),
					// Don't show time.
					'#jscalendar_showsTime' => $jscalendar ? 'false'	: array(),
					// Show 24-hour clock.
					'#jscalendar_timeFormat' => $jscalendar ? '24'	: '',
				);


				$form['scheduler_settings']['unpublish_on'] = array(
					'#type' => 'textfield', 
					'#title' => t('Unpublish on'), 
					'#maxlength' => 25, 
					//we subtract the time zone to show the user the correct time they entered
					//and below that we show the timezone to adjust this time by
					//we store the adjusted timezone value in the database for cron
					
					// If no value is found in the database, we set the default unpublish date to be in one week. (604800 sec)
					'#default_value' => $defaults->unpublish_on ? date('d.m.Y', $defaults->unpublish_on - $defaults->timezone) : date('d.m.Y', time()+604800),
					'#description' => t('Format: %time.', array('%time' => date('d.m.Y'))),
					'#required' => TRUE,
					'#attributes' => $jscalendar ? array('class' => 'jscalendar') : array(),
					// Use only year, month, and day in textfield.
//					'#jscalendar_ifFormat' => $jscalendar ? '%Y-%m-%d' : array(),
					'#jscalendar_ifFormat' => $jscalendar ? '%d.%m.%Y' : array(),
					// Don't show time.
					'#jscalendar_showsTime' => $jscalendar ? 'false'	: array(),
					// Show 24-hour clock.
					'#jscalendar_timeFormat' => $jscalendar ? '24'	: '',
				);
				
				//default to user timezone, if not specified, default to system wide timezone
				global $user;
				$zones = _system_zonelist();
				$form['scheduler_settings']['timezone'] = array(
					// Changed from 'select' to 'hidden' because we don't want this field to be shown to the user
					'#type' => 'hidden', 
					'#title' => t('Time zone'), 
					'#default_value' => $defaults->timezone ? $defaults->timezone : (strlen($user->timezone) ? $user->timezone : variable_get('date_default_timezone', 0)),
					'#options' => $zones, 
					'#description' => t('Select the time zone to (un)publish in.')
				);
			}		 
		} 
	}
}


/**
 * Implementation of hook_nodeapi().
 */
function scheduler_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
	if (user_access('schedule (un)publishing of nodes')) {
		switch ($op) {
			case 'load':
				if ($node->nid) {
					$result = db_query('SELECT * FROM {scheduler} WHERE nid = %d', $node->nid);
					if ($result && db_num_rows($result) > 0) {
						$row = db_fetch_array($result);
						$row['published'] = $row['publish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['publish_on']) : NULL;
						$row['unpublished'] = $row['unpublish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['unpublish_on']) : NULL;
						$node->scheduler = $row;
					}
				}			
				break;
				
			case 'submit':
				// right before we save the node, we need to check if a "publish on" value has been set
				// if it has been set, we want to make sure the node is unpublished
				// since it will be published at a later date
				if ($node->publish_on != '') {
					$node->status = 0;
				}
			
				//adjust the entered times for timezone consideration
				$node->publish_on = $node->publish_on ? strtotime($node->publish_on) + $node->timezone : NULL;
				$node->unpublish_on = $node->unpublish_on ? strtotime($node->unpublish_on) + $node->timezone : NULL;

				break;
			
			case 'insert':
				//only insert into database if we need to (un)publish this node at some date
				if ($node->publish_on != NULL || $node->unpublish_on != NULL) {
					db_query('INSERT INTO {scheduler} (nid, publish_on, unpublish_on, timezone) VALUES (%d, %d, %d, %d)', $node->nid, $node->publish_on, $node->unpublish_on, $node->timezone);
				}
				break;

			case 'update':
				$exists = db_result(db_query('SELECT nid FROM {scheduler} WHERE nid = %d', $node->nid));
					
				//if this node has already been scheduled, update its record
				if ($exists) {
					//only update database if we need to (un)publish this node at some date
					//otherwise the user probably cleared out the (un)publish dates so we should remove the record
					if ($node->publish_on != NULL || $node->unpublish_on != NULL) {
						db_query('UPDATE {scheduler} SET publish_on = %d, unpublish_on = %d, timezone = %d WHERE nid = %d', $node->publish_on, $node->unpublish_on, $node->timezone, $node->nid);
					}
					else {
						db_query('DELETE FROM {scheduler} WHERE nid = %d', $node->nid);
					}
				}
				//node doesn't exist, create a record only if the (un)publish fields are blank
				else if ($node->publish_on != NULL || $node->unpublish_on != NULL) {
					db_query('INSERT INTO {scheduler} (nid, publish_on, unpublish_on, timezone) VALUES (%d, %d, %d, %d)', $node->nid, $node->publish_on, $node->unpublish_on, $node->timezone);
				}
				break;
	
			case 'delete':
				db_query('DELETE FROM {scheduler} WHERE nid = %d', $node->nid);
				break;
		}
	}
}


/**
 * Implementation of hook_cron().
 */
function scheduler_cron() {
	$clear_cache = FALSE;
	
	//if the time now is greater than the time to publish a node, publish it
	$nodes = db_query('SELECT *, (publish_on - timezone) AS utc_publish_on FROM {scheduler} s LEFT JOIN {node} n ON s.nid = n.nid WHERE n.status = 0 AND s.publish_on > 0 AND s.publish_on < %d + s.timezone', time());
	
	while ($node = db_fetch_object($nodes)) {
		$node = node_load($node->nid);
		$node->changed = $node->utc_publish_on;
		$node->status = 1;
		node_save($node);
		
		//if this node is not to be unpublished, then we can delete the record
		if ($node->unpublish_on == 0) {
			db_query('DELETE FROM {scheduler} WHERE nid = %d', $node->nid);
		}
		//we need to unpublish this node at some time so clear the publish on since it's been published
		else {
			db_query('UPDATE {scheduler} SET publish_on = 0 WHERE nid = %d', $node->nid);
		}
		
		//invoke scheduler API
		_scheduler_scheduler_api($node, 'publish');
		
		watchdog('content', t('@type: scheduled publishing of %title.', array('@type' => $node->type, '%title' => $node->title)), WATCHDOG_NOTICE, l(t('view'), 'node/'. $node->nid));
		$clear_cache = TRUE;
	}
	
	//if the time is greater than the time to unpublish a node, unpublish it
	$nodes = db_query('SELECT *, (unpublish_on - timezone) AS utc_unpublish_on FROM {scheduler} s LEFT JOIN {node} n ON s.nid = n.nid WHERE n.status = 1 AND s.unpublish_on > 0 AND s.unpublish_on < %d + s.timezone', time());
	
	while ($node = db_fetch_object($nodes)) {
		//if this node is to be unpublished, we can update the node and remove the record since it can't be republished
		$node = node_load($node->nid);
		$node->changed = $node->utc_publish_on;
		$node->status = 0;
		node_save($node);

		db_query('DELETE FROM {scheduler} WHERE nid = %d', $node->nid);
		
		//invoke scheduler API
		_scheduler_scheduler_api($node, 'unpublish');
		
		watchdog('content', t('@type: scheduled unpublishing of %title.', array('@type' => $node->type, '%title' => $node->title)), WATCHDOG_NOTICE, l(t('view'), 'node/'. $node->nid));
		$clear_cache = TRUE;
	}
	
	if ($clear_cache) {
		// clear the cache so an anonymous poster can see the node being published or unpublished
		cache_clear_all();
	}
}

function _scheduler_run_cron() {
	scheduler_cron();
	if (ob_get_level() > 0) {
		ob_clean();
	}
	exit();
}

/**
 * Scheduler API to perform actions when nodes are (un)published
 *
 * @param $node
 *	The node object
 * @param $action
 *	The action being performed, either "publish" or "unpublish"
 */
function _scheduler_scheduler_api($node, $action) {
	foreach (module_implements('scheduler_api') as $module) {
		$function = $module .'_scheduler_api';
		$function($node, $action); 
	}
}

function _scheduler_timecheck() {
	$now = time();
	return theme('scheduler_timecheck', $now);
}

function theme_scheduler_timecheck($now) {

	drupal_set_title(t('Scheduler OS time check'));

	$t = localtime($now, TRUE);

	$lt = ($t['tm_year']+1900) .'-'. ($t['tm_mon']+1) .'-'. $t['tm_mday'] .' '. $t['tm_hour'] .':'. $t['tm_min'] .':'. $t['tm_sec'];

	$t_options = array(
		'%time' => date("Y-m-d H:i:s", $now), 
		'%lt' => $lt,
	);

	return
		t('Your server reports the UTC time as %time and "localtime" as %lt.', $t_options) . 
	 '<p />'.
		t('If all is well with your server\'s time configuration UTC should match <a target="_blank" href="http://wwp.greenwichmeantime.com/">UTC London Time</a> and the localtime should be the time where you are.') .
		'<p />'.
		t('If this is not the case please have your Unix System Administrator fix your servers time/date configuration.');
}


/**
* Implementation of hook_form_validate()
* Validate the input of the publish and unpublish date fields. Uses the helper function 'timediff_date' (or alternatively 'timediff_timestamp') to make sure that the actual or a future date is entered.
*/
function _scheduler_form_validate($form_id, $form_values) {
	$publishtime ='';
	$unpublishtime = '';
	if (is_array($form_values) && isset($form_values['publish_on'])) {
		$publishtime = strtotime($form_values['publish_on']);
		$timediff_pub = timediff_date($form_values['publish_on']);
		if ($publishtime === false) {
			form_set_error('publish_on', t('The entered publication date is invalid.'));
		}
		else if ($timediff_pub < 0) {
			form_set_error('publish_on', t('The entered publication date occurs in the past.'));
		}
	}

	if (is_array($form_values) && isset($form_values['unpublish_on'])) {
		$unpublishtime = strtotime($form_values['unpublish_on']);
		$timediff_unpub = timediff_date($form_values['unpublish_on']);
		if ($unpublishtime === false) {
			form_set_error('unpublish_on', t('The entered expiration date is invalid.'));
		}
		else if ($timediff_unpub < 0) {
			form_set_error('unpublish_on', t('The entered expiration date occurs in the past.'));
		}
		else if (isset($form_values['publish_on']) && $unpublishtime < $publishtime) {
			form_set_error('unpublish_on', t('The expiration date can\'t lie ahead of the publication date.'));
		}
	}
}


/**
* Function checks the time difference between a specified date to now in days. 
* @param $date
* @return Positive value for number of days in the future, negative value for number of days in the past.
* A date in standard english format 'Y-m-d'.
*/
function timediff_date($date){
	 $date_diff = round( (strtotime($date)-strtotime(date('Y-m-d'))) / 86400, 0 );
	return $date_diff;
}

/**
* Function checks the time difference between a specified timestamp to now in days. 
* @param $date
* @return Positive value for number of days in the future, negative value for number of days in the past.
* A timestamp.
*/
function timediff_timestamp($timestamp){
	$date_diff = round( ($timestamp-strtotime(date('Y-m-d'))) / 86400, 0 );
	return $date_diff;
}