<?php

class Scheduler
{

	public static function updateSchedule($locationid, $options, $openingTimes) {
		if ($openingTimes == '') {
			self::deleteSchedule($locationid);
			return false;
		}
		$nextexec = self::calculateNext($options, $openingTimes);
		$json_options = json_encode($options);
		if ($nextexec !== false) self::upsert($locationid, $nextexec['action'], $nextexec['time'], $json_options);
		else {
			// All times are getting ignored because they are within 5 minutes of each other, delete possible db entries.
			self::deleteSchedule($locationid);
		}
		return true;
	}

	public static function deleteSchedule($locationid) {
		Database::exec("DELETE FROM `reboot_scheduler` 
			WHERE locationid = :lid", array('lid' => $locationid));
	}

	private static function calculateNext($options, $openingTimes) {
		$openingTimes = json_decode($openingTimes, true);
		$now = time();
		$openTimes = [];
		$closeTimes = [];
		foreach ($openingTimes as $row) {
			if (!$options['wol'] && !$options['sd']) continue;
			if ($options['wol']) {
				$open = explode(':', $row['openingtime']);
				$openTime = $open[0] * 60 + $open[1] - $options['wol-offset'];
			}
			if ($options['sd']) {
				$close = explode(':', $row['closingtime']);
				$closeTime = $close[0] * 60 + $close[1] + $options['sd-offset'];
			}
			foreach ($row['days'] as $day) {
				if ($options['wol']) {
					$nextOpen = strtotime(date('Y-m-d H:i', strtotime($day . ' ' . $openTime . ' minutes')));
					if ($nextOpen < $now) $openTimes[] = strtotime(date('Y-m-d H:i', strtotime('next '.$day . ' ' . $openTime . ' minutes')));
					else $openTimes[] = $nextOpen;
				}
				if ($options['sd']) {
					$nextClose = strtotime(date('Y-m-d H:i', strtotime($day . ' ' . $closeTime . ' minutes')));
					if ($nextClose < $now) $closeTimes[] = strtotime(date('Y-m-d H:i', strtotime('next '.$day . ' ' . $closeTime . ' minutes')));
					else $closeTimes[] = $nextClose;
				}
			}
		}

		sort($openTimes);
		sort($closeTimes);
		$res = array();

		if ($options['wol'] && !$options['sd']) {
			$res['action'] = 'wol';
			$res['time'] = $openTimes[0];
			return $res;
		} else if ($options['sd'] && !$options['wol']) {
			$res['action'] = 'sd';
			$res['time'] = $closeTimes[0];
			return $res;
		}

		for ($i = 0; $i <= sizeof($openTimes); $i++) {
			if (abs($openTimes[$i] - $closeTimes[$i]) < 300) {
				// If difference is < 5 min, ignore both events.
				continue;
			} else if (abs($openTimes[$i] - $closeTimes[$i]) < 900)  {
				// If difference is < 15 min, reboot at the earlier time.
				$res['action'] = 'rb';
				$res['time'] = $openTimes[$i] < $closeTimes[$i] ? $openTimes[$i] : $closeTimes[$i];
			} else {
				// Use first event.
				if ($openTimes[$i] < $closeTimes[$i]) {
					$res['action'] = 'wol';
					$res['time'] = $openTimes[$i];
				} else {
					$res['action'] = 'sd';
					$res['time'] =$closeTimes[$i];
				}
			}
			return $res;
		}
		return false;
	}

	private static function upsert($locationid, $action, $nextexec, $options) {
		$schedule = Database::queryFirst("SELECT locationid 
			FROM `reboot_scheduler`
			WHERE locationid = :lid", array(
				'lid' => $locationid
		));
		if ($schedule === false) {
			Database::exec("INSERT INTO `reboot_scheduler` (locationid, action, nextexecution, options) 
				VALUES (:lid, :act, :next, :opt)", array(
					'lid' => $locationid,
					'act' => $action,
					'next' => $nextexec,
					'opt' => $options
			));
		} else {
			Database::exec("UPDATE `reboot_scheduler` 
				SET action = :act, nextexecution = :next, options = :opt
				WHERE locationid = :lid", array(
					'act' => $action,
					'next' => $nextexec,
					'opt' => $options,
					'lid' => $locationid
			));
		}
		return true;
	}

}