<?
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'),
);

$herinfo = get_herinfo($db);

if (isset($_GET['period_id'])) $period_id = $_GET['period_id'];
else $period_id = $herinfo['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);

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) error_system('toets '.$toets.' niet gevonden');
	$toetsen[$toets]['pta_id'] = $pta_id;
}
	
$rooster = mdb2_all_assoc_rekey($db, "SELECT pta_id, moment_id FROM rooster WHERE period_id = %i", $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']]];
		} else $toetsen[$id]['color'] = NULL;
	}
}

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

        $toetsen[$toets]['color'] = $color;

        //echo("start: $toets\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']]++;
                }

                $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;
}

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

if (!check_consistent()) {
	echo("{ 'consistent': 'false' }");
	exit;
}

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

if (!$gevonden) {
	echo('{}');
	exit;
}
$result = array('ok' => array(0), 'nak' => array());


for ($i = 0; $i < $max_colors; $i++) {
	$false = 0;
	foreach ($toetsen[$gevonden]['neighbors'] as $neighbor => $tmp) {
		if ($toetsen[$neighbor]['color'] === $i) {
			$false = 1;
			break;
		}
	}
	if (!$false && probeer_kleur($gevonden, $i, $max_colors)) {
		$result['ok'][] = $color_to_moment[$i];
	} else {
		$result['nak'][] = $color_to_moment[$i];
	}
}
echo(json_encode($result));
?>