<?php namespace App\Messages\Helpers;

use DateTimeZone;
use Carbon\Carbon;

class Scheduler
{
    private $sendAt;
    private $sendAtNoDelay;
    private $countryCode;
    private $defaultTimezone;
    private $acceptedFrom;
    private $acceptedTo;
    private $timezone;

    public function __construct(Carbon $sendAtNoDelay, $countryCode, $defaultTimezone, $silentFrom, $silentTo)
    {

        $this->sendAtNoDelay = $sendAtNoDelay;
        $this->countryCode = $countryCode;
        $this->defaultTimezone = $defaultTimezone;

        if ($silentFrom > $silentTo) {
            $this->acceptedFrom = $silentTo;
            $this->acceptedTo = $silentFrom;
        } else {
            $this->acceptedFrom = $silentFrom;
            $this->acceptedTo = $silentTo;
        }

        $this->timezone = $this->getTimezone($this->countryCode, $this->defaultTimezone);
        $this->sendAt = $this->sendAtNoDelay->setTimezone($this->timezone);
    }

    public function addDelay($delay = null, $delayType = null, $test = false)
    {
        if ($test) {
            if ($delayType === 'minute') $this->sendAt = $this->sendAt->addMinutes(2);
            if ($delayType === 'hour') $this->sendAt = $this->sendAt->addMinutes(5);
            if ($delayType === 'day') $this->sendAt = $this->sendAt->addMinutes(10);
        } else {
            if ($delayType === 'minute') $this->sendAt->addMinutes($delay);
            if ($delayType === 'hour') $this->sendAt = $this->sendAt->addHours($delay);
            if ($delayType === 'day') $this->sendAt = $this->sendAt->addDays($delay);
        }

        return $this;
    }

    public function getSendAt(): Carbon
    {
        list($acceptedFrom, $acceptedTo) = $this->getAcceptedFromAndTo();

        if (!$this->inValidTimes($this->sendAt, $acceptedFrom, $acceptedTo)) {
            $this->sendAt = $acceptedFrom > $this->sendAt ?
                $acceptedFrom->copy()->timezone('UTC') : $acceptedFrom->copy()->addDay()->timezone('UTC');
        }

        return $this->applyRestrictions($this->sendAt);
    }

    private function inValidTimes(Carbon $sendAt, Carbon $acceptedFrom, Carbon $acceptedTo): bool
    {
        return $sendAt->toDateTimeString() >= $acceptedFrom->copy()->toDateTimeString() &&
            $sendAt->toDateTimeString() <= $acceptedTo->copy()->toDateTimeString();
    }

    private function getAcceptedFromAndTo(): array
    {
        list($hour, $minute) = explode(':', $this->acceptedFrom);
        $acceptedFrom = $this->sendAt->copy()->setTime($hour, $minute);

        list($hour, $minute) = explode(':', $this->acceptedTo);
        $acceptedTo = $this->sendAt->copy()->setTime($hour, $minute);

        return [$acceptedFrom, $acceptedTo];
    }

    private function getTimezone($countryCode, $defaultTimezone)
    {
        if (strlen($countryCode) != 2) return $defaultTimezone;

        $timezones = (DateTimeZone::listIdentifiers(DateTimeZone::PER_COUNTRY, $countryCode));

        return count($timezones) > 0 ? $timezones[0] : $defaultTimezone;
    }

    private function applyRestrictions(Carbon $sendAt)
    {
        $countryCode = mb_strtoupper($this->countryCode);

        switch ($countryCode) {
            case 'FR':
                $acceptedFromFR = $sendAt->copy()->setTime(8, 0);
                $acceptedToFr = $sendAt->copy()->setTime(19, 55);

                if ($acceptedToFr < $sendAt) {
                    if ($this->acceptedFrom >= '08:00') {
                        list($hour, $minute) = explode(':', $this->acceptedFrom);
                        $sendAt = $acceptedFromFR->setTime($hour, $minute)->addDay(1)->copy();
                    } else $sendAt = $acceptedFromFR->copy()->addDay(1);
                }

                if ($sendAt->isSunday()) {
                    list($hour, $minute) = explode(':', $this->acceptedFrom);

                    $sendAt = $sendAt->addDay()->setTime($hour, $minute);
                }

                return $sendAt->setTimezone('UTC');
                break;
            case 'ID':
                $acceptedFromFR = $sendAt->copy()->setTime(9, 0);
                $acceptedToFr = $sendAt->copy()->setTime(20, 55);

                if ($acceptedToFr < $sendAt) {
                    if ($this->acceptedFrom >= '09:00') {
                        list($hour, $minute) = explode(':', $this->acceptedFrom);
                        $sendAt = $acceptedFromFR->setTime($hour, $minute)->addDay(1)->copy();
                    } else $sendAt = $acceptedFromFR->copy()->addDay(1);
                }

                return $sendAt->setTimezone('UTC');
                break;
            default:
                return $sendAt->setTimezone('UTC');
        }
    }
}