<?php

namespace humhub\modules\animal_management\notifications;

use humhub\modules\animal_management\models\AnimalTransfer;
use humhub\modules\space\models\Space;
use humhub\modules\user\models\User;

class TransferNotifier
{
    public static function notifyStatusChange(AnimalTransfer $transfer, string $eventType, ?User $originator = null, string $details = ''): int
    {
        $animal = $transfer->animal;
        if ($animal === null) {
            return 0;
        }

        $fromSpace = $transfer->getFromSpace();
        $toSpace = $transfer->getToSpace();
        if (!$fromSpace instanceof Space || !$toSpace instanceof Space) {
            return 0;
        }

        $targetSpaces = static::targetSpacesForEvent($eventType, $fromSpace, $toSpace);
        $sentCount = 0;
        $seenRecipients = [];

        foreach ($targetSpaces as $space) {
            $recipients = static::privilegedUsersForSpace($space);
            foreach ($recipients as $recipient) {
                $recipientId = (int)$recipient->id;
                if ($originator instanceof User && $recipientId === (int)$originator->id) {
                    continue;
                }

                if (isset($seenRecipients[$recipientId])) {
                    continue;
                }

                $seenRecipients[$recipientId] = true;
                $notification = TransferStatusNotification::instance();
                if ($originator instanceof User) {
                    $notification->from($originator);
                }
                $notification->animalName = $animal->getDisplayName();
                $notification->fromSpaceName = (string)$fromSpace->name;
                $notification->toSpaceName = (string)$toSpace->name;
                $notification->spaceGuid = (string)$space->guid;
                $notification->eventType = $eventType;
                $notification->details = $details;
                $notification->payload([
                    'animalName' => $notification->animalName,
                    'fromSpaceName' => $notification->fromSpaceName,
                    'toSpaceName' => $notification->toSpaceName,
                    'spaceGuid' => $notification->spaceGuid,
                    'eventType' => $notification->eventType,
                    'details' => $notification->details,
                ]);
                $notification->send($recipient);
                $sentCount++;
            }
        }

        return $sentCount;
    }

    public static function privilegedUsersForSpace(Space $space): array
    {
        $recipients = [];

        foreach ($space->getPrivilegedGroupUsers() as $users) {
            foreach ($users as $user) {
                if ($user instanceof User && (int)$user->status === User::STATUS_ENABLED) {
                    $recipients[(int)$user->id] = $user;
                }
            }
        }

        if (empty($recipients)) {
            $owner = $space->getOwnerUser()->one();
            if ($owner instanceof User && (int)$owner->status === User::STATUS_ENABLED) {
                $recipients[(int)$owner->id] = $owner;
            }
        }

        return $recipients;
    }

    private static function targetSpacesForEvent(string $eventType, Space $fromSpace, Space $toSpace): array
    {
        $spaces = [];

        switch ($eventType) {
            case 'accepted':
            case 'declined':
                $spaces[] = $fromSpace;
                break;
            case 'cancelled':
                $spaces[] = $toSpace;
                break;
            case 'completed':
                $spaces[] = $fromSpace;
                break;
            default:
                $spaces[] = $fromSpace;
                $spaces[] = $toSpace;
                break;
        }

        $unique = [];
        foreach ($spaces as $space) {
            $key = (int)$space->contentcontainer_id;
            if (!isset($unique[$key])) {
                $unique[$key] = $space;
            }
        }

        return array_values($unique);
    }
}