<?php

/**
 * @file
 * Functions for calculating leaders and helpers for discussion groups
 */


/**
 * Function for calculating and assigning leaders and helpers to active study group sessions
 */
function booking_studygroups_leaders_calculate() {
	global $event;
	
	$calculation_messages = array();
	
	//get a randomly ordered list of people to work with
	$people = _booking_shuffle_assoc(_booking_studygroups_retrieve_eligible_people());
	
	//get details of the study groups
	$groups = _booking_studygroups_retrieve_groups();
	
	//loop through the list of people
	foreach ($people as $person)
	{
		$age = _booking_get_age_years($person->booking_dob);	
		$calculation_messages[] = t('Processing eligible Leader/helper with id !id and age !age', 
			array('!id' => $person->nid, '!age' => $age)
		);
		
		foreach ($groups as $studygroup)
		{
			//watchdog('booking_debug', "<pre>Study Group Element\n@info</pre>", array('@info' => print_r( $studygroup, true)));
			if ($age >= 22 && $studygroup->leader_nid == 0)
			{
				$studygroup->leader_nid = $person->nid;
				$calculation_messages[] = t("Study Group Assignment as leader for nid !nid to group !descrip at session id !sid", 
					array('!nid' => $person->nid, '!descrip' => $studygroup->booking_studygroup_descrip, '!sid' => $studygroup->session_id, '@info' => print_r( $studygroup, true)));			
				break;
			}
			elseif ($age < 22 && $studygroup->helper_nid == 0)
			{
				$studygroup->helper_nid = $person->nid;
				$calculation_messages[] = t("Study Group Assignment as helper for nid !nid to group !descrip at session id !sid", 
					array('!nid' => $person->nid, '!descrip' => $studygroup->booking_studygroup_descrip, '!sid' => $studygroup->session_id, '@info' => print_r( $studygroup, true)));			
				break;
			}
		}		

		//if someone is 22 or over, they're a leader
			//$next_group_index = $groups[_booking_get_next_studygroup('leader_nid', $groups)];
			
			//$groups[$next_group_index]->leader_nid = $person->nid;
		//if someone is under 22, they're a helper

		//left over people become a reserve leader
	}
	
	watchdog('booking', "<pre>Study Group Leader/Helper calculation\n" . implode("\n", $calculation_messages) . "</pre>");	
	
	//input the data to the database
}

function _booking_get_next_studygroup($type, $studygroups) {
	
	$count = count($studygroups) - 1;
	
	for ($i = 0; $i < $count; $i++) 
	{
		$group = $studygroups[$i];
		$leader = $group->leader_nid;
		//watchdog('booking_debug', "<pre>Study Group Element at index $i:\n@info</pre>", array('@info' => print_r( $group, true)));		
		//watchdog('booking_debug', "<pre>Study Group Leader NID at index $i:\n@info</pre>", array('@info' => var_dump($group)));	
		
		if ($leader == 0)
		{
			return $i;
		}
		
	}
	
}

/**
 * Function for 
 */
function _booking_studygroups_retrieve_eligible_people() {
	global $event;
	
	$attendees = array();
	
	//select males that are booked in
	$query = db_select('booking_person', 'p');
	$db_and = db_and();
	$db_and->condition('p.booking_eventid', $event->eid, '=');
	$db_and->condition('p.booking_gender', 'M', '=');
	$db_and->condition('p.booking_status', 1, '=');
	$query->condition($db_and);
	$query->fields('p');
	$bookedin_result = $query->execute();					
	
	//iterate over the attendee associative array and add some fields	
	foreach ($bookedin_result as $person)
	{
		
		$person->processed = 0;
		$person->leading = array();
		$person->helping = array();
		$person->reserve_leading = array();
		$attendees[] = $person;
	}	
	
	//select males that are on the waiting list up to position number 100
	$result2 = db_query('SELECT DISTINCT nid, booking_firstname, booking_lastname, booking_state, booking_readinggroup, booking_country, booking_status, booking_dob, booking_gender
	                    FROM (
	                      SELECT p.nid, p.booking_firstname, p.booking_lastname, p.booking_state, p.booking_country, p.booking_readinggroup, pay.booking_payment_date, p.booking_status, p.booking_gender, p.booking_dob
	                      FROM {booking_person} p, {booking_payment} pay
					      				WHERE booking_eventid = :eid and p.nid = pay.booking_person_nid and ( booking_status = 2 or booking_status = 4)
												LIMIT 100
	                    ) AS booking
								WHERE booking_gender = \'M\'
	              ORDER BY booking_status, booking_payment_date',
						array(':eid' => $event->eid));			
	
	//iterate over the attendee associative array and add some fields	
	foreach ($result2 as $person)
	{
		
		$person->processed = 0;
		$person->leading = array();
		$person->helping = array();
		$person->reserve_leading = array();
		$attendees[] = $person;
	}		
	
	//watchdog('booking', "<pre>Eligible Leaders/Helpers List:\n@info</pre>", array('@info' => print_r( $attendees, true)));
	
	return $attendees;
	
}

/**
 * Function for 
 */
function _booking_studygroups_retrieve_groups() {
	global $event;
	
	$groups = array();
		
	//select all the study groups for this event id
	$studygroup = db_query("SELECT * FROM {booking_studygroup_list} WHERE booking_eventid = :eid", array(':eid' => $event->eid));
	$group_mapping = $studygroup->fetchAllAssoc('sid');		
	
	//select the number of study group sessions
	//assume they all have the same number of sessions
	//$num_sessions = $studygroup->booking_num_group_sessions;
	
	foreach ($group_mapping as $group)
	{
		//watchdog('booking_debug', "<pre>Study Group Element:\n@info</pre>", array('@info' => print_r( $group, true)));		
		for ($i = 1; $i <= 16; $i++)
		{
			$new_group = clone $group;
			
			$new_group->session_id = $i;
			$new_group->leader_nid = 0;
			$new_group->helper_nid = 0;
			$new_group->reserve_nid = 0;
			$new_group->processed = 0;
			
			$groups[] = $new_group;
		}
	}
	
	//watchdog('booking', "<pre>Study Group Sessions:\n@info</pre>", array('@info' => print_r( $groups, true)));
	return $groups;
	
}

/**
 * autocomplete helper to look up names for room allocations
 * based on https://www.drupal.org/node/854216
 * $string = string for search 
 */
function _booking_studygroups_name_autocomplete($string) {
	global $event;
	$matches = array();

	$query = db_select('booking_person', 'p')
					->fields('p', array('nid', 'booking_firstname', 'booking_lastname'));
	$db_or = db_or()->condition('p.booking_lastname', '%' . db_like($string) . '%', 'LIKE')->condition('p.booking_firstname', '%' . db_like($string) . '%', 'LIKE');
	$db_and = db_and()->condition($db_or)->condition('p.booking_eventid', $event->eid, '=');
	$result = $query->condition($db_and)						
					->execute();
	
	// save the query to matches
	foreach ($result as $row) {
		$name = $row->booking_lastname . ', ' . $row->booking_firstname . ' [' . $row->nid . ']';
		$matches[$name] = $name;
	}
	
	// Return the result to the form in json
	drupal_json_output($matches);
}

/**
 * Function to allow admin to edit leaders and helpers for a study group
 */
function booking_studygroup_leadhelp_edit_form($node, &$form_state, $group_id) {
	global $event;

	//verify that $group_id is a number
	if (! preg_match('/^[0-9]+$/', $group_id)) {
		drupal_set_message("Error: Invalid study group ID '" . $group_id . "' supplied. Unable to edit group leaders and helpers.", 'error', FALSE);
		drupal_goto('admin/booking/studygroups');
		return "";
	}	
	
	//try to select the study group for this $group_id
	$studygroup = db_query("SELECT * FROM {booking_studygroup_list} WHERE sid = :sid", array(':sid' => $group_id))
		->fetchObject();
	
	if (! $studygroup) {
		drupal_set_message("Error: Could not find matching study group ID. Unable to edit leaders/helpers.", 'error', FALSE);
		drupal_goto('admin/booking/studygroups');
		return "";			
	}

	$prefix = t("<h2>Study Group &dash; !descrip</h2><p>Edit leaders and helpers for this group.</p>", 
		array('!descrip' => $studygroup->booking_studygroup_descrip));

	//define the table header
	$header = array (
		'sid' =>  array('data' => t('Study Group Session ID'), 'field' => 'sid'),
		'booking_assign_leader' =>  array('data' => t('Leader')),		
		'booking_assign_helper' =>  array('data' => t('Helper')),	
		'booking_assign_reserveleader' =>  array('data' => t('Reserve Leader')),		
	);	
	
	//attach the custom css
	$form['#attached']['css'] = array(
	  drupal_get_path('module', 'booking') . '/booking.css',
	);

	//create the container element for the whole table					
	$form['studygroups'] = array(
		'#prefix' => '<div id="studygroups">',
		'#suffix' => '</div>',
		'#tree' => TRUE,
		'#theme' => 'table',
		'#header' => $header,
		'#rows' => array(),
	);
	
	//define the default fields in a table row
	$default_row = array();
	$default_row['sid'] = "";
	$default_row['booking_studygroup_leader'] = "";
	$default_row['booking_studygroup_helper'] = "";
	$default_row['booking_studygroup_reserveleader'] = "";

  //get the list of study group session memberships
	$session_members_query = db_query("SELECT m.*, p.* FROM {booking_studygroup_mapping} m
		inner join {booking_person} p on p.nid = m.booking_node_id
		WHERE m.booking_studygroup_id = :gid AND m.booking_studygroup_role > 0", 
		array(':gid' => $group_id));
  $session_members = $session_members_query->fetchAllAssoc('booking_node_id');	

	//create an array representing the existing leaders/helpers for this group
	$existing_leaders = array();
	foreach ($session_members as $person) {
		$existing_leaders[$person->booking_session_id][$person->booking_studygroup_role] =  $person->booking_lastname 
			. ', ' . $person->booking_firstname . ' [' . $person->booking_nodeid . ']';
	}	

	//create the rows for the individual sessions (instances really) of this study group
	for ($i = 0; $i < $studygroup->booking_num_group_sessions; $i++) {

		$leader = array (
			'#id'   => 'booking-studygroup-leader-' . $i,
			'#type' => 'textfield',
			'#title' => 'Name',
			'#title_display' => 'invisible',
			'#name' => 'booking_studygroup_leader[' . $i . ']',
			'#size' => 100,
			'#autocomplete_path' => 'booking/studygroups/autocomplete',
			'#value' => (!empty($existing_leaders[$i][1])) ? $existing_leaders[$i][1] : '',	
			'#attributes' => array('style' => array('width:200px')),
		);

		$helper = array (
			'#id'   => 'booking-studygroup-helper-' . $i,
			'#type' => 'textfield',
			'#title' => 'Name',
			'#title_display' => 'invisible',
			'#name' => 'booking_studygroup_helper[' . $i . ']',
			'#size' => 100,
			'#autocomplete_path' => 'booking/studygroups/autocomplete',
			'#value' => (!empty($existing_leaders[$i][2])) ? $existing_leaders[$i][2] : '',	
			'#attributes' => array('style' => array('width:200px')),
		);

		$reserveleader = array (
			'#id'   => 'booking-studygroup-reserveleader-' . $i,
			'#type' => 'textfield',
			'#title' => 'Name',
			'#title_display' => 'invisible',
			'#name' => 'booking_studygroup_reserveleader[' . $i . ']',
			'#size' => 100,
			'#autocomplete_path' => 'booking/studygroups/autocomplete',
			'#value' => (!empty($existing_leaders[$i][3])) ? $existing_leaders[$i][3] : '',	
			'#attributes' => array('style' => array('width:200px')),
		);				
		
		$form['studygroups'][$i] = array(
			'booking-studygroup-leader' => &$leader,
			'booking-studygroup-helper' => &$helper,
			'booking-studygroup-reserveleader' => &$reserveleader,
		);

		$new_row = array();
		$new_row['sid'] = $i;
		$new_row['booking_studygroup_leader'] = array('data' => &$leader);
		$new_row['booking_studygroup_helper'] = array('data' => &$helper);
		$new_row['booking_studygroup_reserveleader'] = array('data' => &$reserveleader);
		$form['studygroups']['#rows'][$i] = $new_row;
		
		unset($leader);
		unset($helper);
		unset($reserveleader);
	}

	//close out the form
	$form['submit'] = array (
		'#type' => 'submit',
		'#value' => t('Submit'),
	);	

	return array (
		'form' => $form,		
	);	
}