<?
require('phplib/phplib.php');
require('common.php');

check_admin();

/*
$toetsen = get_toetsen_from_csv(
	'export1415-1.csv',
	array('5H.schk/TP1', '6V.wisD/TP1'),
	array(
		'6V.wisAC/TP1' => array('6V.wisA/TP1', '6V.wisC/TP1'),
		'5H.kualg/TP1' => array('5H.kumu/TP1', '5H.kubv/TP1'))
);
	//array('5H.schk/TP1', '6V.wisD/TP1'),
 */

$db = mdb2_open($dsn);

$buiten_beschouwing = array(
//	'5H.netl/TP2 ST lit',
//	'6V.netl/TP2 ST literatuur',
);
$samenvoegen = array(
//	'5V.wisAC/TP2 ST1' => array('5V.wisA/TP2 ST1', '5V.wisC/TP2 ST1'),
//	'6V.wisAC/TP2 ST3' => array('6V.wisA/TP2 ST3', '6V.wisC/TP2 ST3'),
);

$herinfo = get_better_herinfo($db, $_GET);
$period_id = $herinfo['period_id'];

$buiten_beschouwing = get_buiten_beschouwing($db, $period_id);

$samenvoegen = get_samenvoegen($db, $period_id);

$toetsen = get_toetsen_from_db($db, $period_id, $buiten_beschouwing, $samenvoegen);

$moments = mdb2_all_assoc_rekey($db, <<<EOQ
SELECT * FROM moments WHERE period_id = %i
EOQ
, $period_id);

$colors = array("#fbb4ae", "#b3cde3", "#ccebc5", "#decbe4", "#fed9a6", "#ffffcc", "#e5d8bd", "#fddaec", "#f2f2f2");

$moment_color_index = 0;
if (count($moments) > count($colors)) error_system('te weinig kleuren');

$moment_to_color = array();
$color_to_moment = array();
foreach ($moments as $id => $moment) {
	$moment_to_color[$id] = count($color_to_moment);
	$color_to_moment[] = $id;
}

$max_colors = count($color_to_moment);

$toetstranslate = get_toetsnames_index($db, $period_id);

foreach ($toetsen as $toets => $info) {
	$pta_id = mdb2_single_val($db, <<<EOQ
SELECT pta_id FROM ptas
JOIN rex USING (pta_id, subj_id)
JOIN $kldv.subj USING (subj_id)
WHERE period_id = %i AND CONCAT(CASE WHEN pta_period <= 3 THEN '4'
		                WHEN pta_period <= 6 THEN '5'
				                ELSE '6' END, pta_target, '.', subj_abbrev, '/TP',
						                (pta_period-1)%%3 + 1, ' ', stvt, IFNULL(shortdesc, '')) = '%q'
EOQ
	, $period_id, $toets);
	if (!$pta_id) {
		 $pta_ids = mdb2_single_val($db, <<<EOQ
SELECT GROUP_CONCAT(pta_id ORDER BY pta_id SEPARATOR '_') FROM group_ids
	JOIN groepeer USING (group_id)
	JOIN ptas USING (pta_id)
	WHERE group_name = '%q' AND year_id = {$herinfo['year_id']}
EOQ
		, $toets);
	        if (!$pta_ids) error_system('toets '.$toets.' niet gevonden');
		$toetsen[$toets]['pta_id'] = $pta_ids;
	} else $toetsen[$toets]['pta_id'] = $pta_id;
	assert($toetsen[$toets]['pta_id'] == $toetstranslate[$toets]);
}
	
//$rooster = mdb2_all_assoc_rekey($db, "SELECT pta_id, moment_id FROM rooster WHERE period_id = %i", $period_id);
/* the GROUP BY IFNULL( trick is to not group the NULL values in group_id */
$rooster = mdb2_all_assoc_rekey($db, <<<EOQ
SELECT GROUP_CONCAT(pta_id ORDER BY pta_id SEPARATOR '_'), moment_id
FROM rooster
LEFT JOIN groepeer USING (pta_id, period_id)
WHERE period_id = %i
GROUP BY IFNULL(group_id, CONCAT('_', rooster_id)), moment_id
EOQ
, $period_id);

function set_graph_id(&$toets, $id) {
	global $toetsen, $collections;
	assert(!$toets['graph']);
	$toets['graph'] = $id;
	foreach ($toets['neighbors'] as $naam => $aantal) {
		if ($toetsen[$naam]['graph'] === NULL) { 
			$collections[$id]['list'][] = $naam;
			set_graph_id($toetsen[$naam], $id);
		}
	}
}
$graph_id = 0;
$collections = array();

foreach ($toetsen as $naam => &$value) {
	if ($value['graph'] !== NULL) continue;
	$collections[$graph_id] = array('list' => array($naam));
	set_graph_id($value, $graph_id++);
}
unset($value);

function set_colors_from_rooster() {
	global $toetsen, $moment_to_color, $color_to_moment, $rooster;
	foreach ($toetsen as $id => $info) {
		if (isset($rooster[$info['pta_id']])) {
			$toetsen[$id]['color'] = $moment_to_color[$rooster[$info['pta_id']]];
			$toetsen[$id]['uncolored'] = false;
		} else {
			$toetsen[$id]['color'] = NULL;
			$toetsen[$id]['uncolored'] = true;
		}
	}
}

function check_consistent() {
	global $toetsen, $collections, $max_colors;
	set_colors_from_rooster();
	foreach ($toetsen as $toets) {
		if ($toets['color'] === NULL) continue;
		foreach ($toets['neighbors'] as $neighbor => $tmp) {
			if ($toetsen[$neighbor]['color'] === $toets['color']) return false;
		}
	}
	return true;
}

function uncolor() {
	global $toetsen;
	foreach ($toetsen as $id => $info) {
		if ($info['uncolored'] === true) {
			$toetsen[$id]['color'] = NULL;
		}
	}
}

function probeer_kleur($toets, $color, $max_colors) {
        global $toetsen;

	//if ($toetsen[$toets]['uncolored'] && $toetsen[$toets]['color'] !== NULL) die("impossible");
        $toetsen[$toets]['color'] = $color;

        //echo("start: $toets ($color)\n");

        foreach ($toetsen[$toets]['neighbors'] as $neighbor => $tmp) {
                if ($toetsen[$neighbor]['color'] !== NULL) continue;
                $colors = array();
                //$colorless = array();
                for ($i = 0; $i < $max_colors; $i++) $colors[$i] = 0;
                //echo("buren: $neighbor\n");

                foreach ($toetsen[$neighbor]['neighbors'] as $second_neighbor => $tmp) {
                        if ($toetsen[$second_neighbor]['color'] !== NULL)
                                $colors[$toetsen[$second_neighbor]['color']]++;
                }

		//print_r($colors);
                $possible = 0;

                foreach ($colors as $color => $count) {
                        if ($count > 0) continue;
                        //echo("probeer $neighbor $color\n");
                        if (probeer_kleur($neighbor, $color, $max_colors)) {
                                $possible++;
                                break;
                        }
                }

                if (!$possible) {
                        $toetsen[$toets]['color'] = NULL;
                        return false;
                }

        }

        return true;
}

function probeer_connected($toets, $color, $max_colors) {
	global $toetsen;
	//echo("toets to place $toets with color $color ($max_colors)\n");
	if (!probeer_kleur($toets, $color, $max_colors)) {
		//echo("faal\n");
		return false;
	}

	//check some stuff
	//print_r($toetsen[$toets]);
	$graph_id = $toetsen[$toets]['graph'];
	//echo("graph_id=$graph_id\n");

//	foreach ($toetsen as $name => $info) {
//		if ($info['graph'] != $graph_id) continue;
		//echo($name." ".($info['color'] === NULL?'NULL':$info['color'])." ".(($info['uncolored']?'UNCOLORED':'COLORED'))."\n");
//	}
	uncolor();
	return true;
}

header('Content-type: text/plain; charset=UTF-8');
//header('Content-type: application/json; charset=UTF-8');

//echo("color to moment:\n");
//print_r($color_to_moment);
if (!check_consistent()) {

	$result = array(
		'consistent' => 'false',
		'ok' => array(0),
		'nak' => array()
	);
	for ($i = 0; $i < $max_colors; $i++) {
		$result['nak'][] = $color_to_moment[$i];
	}
	//echo("{ 'consistent': 'false' }");
	echo(json_encode($result));
	exit;

}

$gevonden = NULL;
foreach ($toetsen as $id => $toets) {
	if ($toets['pta_id'] == $_GET['pta_id']) {
		$gevonden =  $id;
		break;
	}
}

// een niet gevonden toets, kan niet gevonden zijn omdat
// er opeens geen inschrijvingen meer zijn, deze toets
// mag teruggeplaatst worden naar het 'te roosteren' vlak
if (!$gevonden) {

	$result = array(
		'ok' => array(0),
		'nak' => array()
	);
	for ($i = 0; $i < $max_colors; $i++) {
		$result['nak'][] = $color_to_moment[$i];
	}
	echo(json_encode($result));
	exit;
}
$result = array('ok' => array(0), 'nak' => array());

	//echo('{}');
//	exit;


$faalkleur = array();
for ($i = 0; $i < $max_colors; $i++) {
	foreach ($toetsen[$gevonden]['neighbors'] as $neighbor => $tmp) {
		if ($toetsen[$neighbor]['color'] === $i) {
			$faalkleur[$i] = true;
			break;
		}
	}
}

for ($i = 0; $i < $max_colors; $i++) {
	if (!isset($faalkleur[$i]) && probeer_connected($gevonden, $i, $max_colors)) {
		$result['ok'][] = $color_to_moment[$i];
	} else {
		$result['nak'][] = $color_to_moment[$i];
	}
}
echo(json_encode($result));
?>