<?php

/**
 * @link https://www.humhub.org/
 * @copyright Copyright (c) 2017 HumHub GmbH & Co. KG
 * @license https://www.humhub.com/licences
 *
 */

/**
 * Created by PhpStorm.
 * User: buddha
 * Date: 14.09.2017
 * Time: 12:33
 */

namespace humhub\modules\calendar\interfaces;

use DateInterval;
use DateTime;
use humhub\modules\calendar\helpers\CalendarUtils;
use humhub\modules\calendar\interfaces\event\CalendarEntryTypeSetting;
use humhub\modules\calendar\interfaces\event\CalendarEventIF;
use humhub\modules\calendar\interfaces\event\CalendarItemsEvent;
use humhub\modules\calendar\interfaces\event\CalendarItemTypesEvent;
use humhub\modules\calendar\interfaces\event\CalendarTypeArrayWrapper;
use humhub\modules\calendar\interfaces\event\CalendarTypeSetting;
use humhub\modules\calendar\interfaces\event\legacy\CalendarEventIFWrapper;
use humhub\modules\calendar\models\CalendarEntryQuery;
use humhub\modules\calendar\models\CalendarEntryType;
use humhub\modules\content\components\ContentActiveRecord;
use humhub\modules\content\components\ContentContainerActiveRecord;
use humhub\modules\content\models\Content;
use yii\base\Component;
use yii\helpers\ArrayHelper;

/**
 * This service component supports integration functionality and is responsible for retrieving
 * calendar related data from other modules using the calendar interface.
 *
 * You can receive an instance of this component by calling
 *
 * ```php
 * $calendarService = Yii::$app->getModule('calendar')->get(CalendarService::class);
 * ```
 * @package humhub\modules\calendar\interfaces
 */
class CalendarService extends Component
{
    /**
     * Used for assembling all available item types provided by other modules
     */
    public const EVENT_GET_ITEM_TYPES = 'getItemTypes';

    /**
     * Used for assembling all calendar items of other modules
     */
    public const EVENT_FIND_ITEMS = 'findItems';

    /**
     * @var array
     */
    private static $resultCache = [];

    /**
     * Searches for integrated calendars of other modules.
     * Modules can append their event types by calling CalendarItemTypeEvent::addType() and providing
     * a unique key and options as for example:
     *
     * ```php
     * $event->addType('myType', [
     *      'title' => Yii::t('MyModule.base', 'My Type),
     *      'color' => '#2c99d6' // default color for this even type
     * ]);
     * ```
     *
     * The module has to get sure it only returns results either if $contentContainer is not provided or the given
     * module is enabled for the given ContentContainerActiveRecord.
     *
     * @param null ContentContainerActiveRecord $contentContainer
     * @return array|null
     */
    public function getCalendarItemTypes(?ContentContainerActiveRecord $contentContainer = null)
    {
        $containerKey = ($contentContainer) ? $contentContainer->contentcontainer_id : 'global';

        if (isset(static::$resultCache[$containerKey])) {
            return static::$resultCache[$containerKey];
        }

        $event = new CalendarItemTypesEvent(['contentContainer' => $contentContainer]);
        $this->trigger(self::EVENT_GET_ITEM_TYPES, $event);

        $result = [new CalendarEntryTypeSetting(['type' => new CalendarEntryType(), 'contentContainer' => $contentContainer])];
        foreach ($event->getTypes() as $key => $type) {
            $type = is_array($type) ? new CalendarTypeArrayWrapper(['key' => $key, 'options' => $type]) : $type;
            $result[] = new CalendarTypeSetting(['type' => $type, 'contentContainer' => $contentContainer]);
        }

        return static::$resultCache[$containerKey] = $result;
    }

    public static function flushCache()
    {
        static::$resultCache = [];
    }


    /**
     * Merges all CalendarItems for a given ContentContainerActiveRecord filtered by $from, $to and $filters.
     *
     * CalendarItems can either be CalendarEntries or CalendarItems provided
     *
     * @param DateTime $start
     * @param DateTime $end
     * @param array $filters
     * @param ContentContainerActiveRecord $contentContainer
     * @param null $limit
     * @param bool $expand
     * @param array $types
     * @return CalendarEventIF[]
     * @throws \Throwable
     */
    public function getCalendarItems(?DateTime $start = null, ?DateTime $end = null, $filters = [], ?ContentContainerActiveRecord $contentContainer = null, $limit = null, $expand = true, $types = [])
    {
        $result = [];

        $event = new CalendarItemsEvent([
            'contentContainer' => $contentContainer,
            'start' => $start ? clone $start : null,
            'end' => $end ? clone $end : null,
            'filters' => $filters,
            'limit' => $limit,
            'expand' => $expand,
        ]);

        $this->trigger(static::EVENT_FIND_ITEMS, $event);

        foreach ($event->getItems() as $itemTypeKey => $items) {
            $itemType = $this->getItemType($itemTypeKey, $contentContainer);

            if ($itemType && $itemType->isEnabled()) {
                foreach ($items as $item) {
                    if (is_array($item)) {
                        $result[] = new CalendarEventIFWrapper(['itemType' => $itemType, 'options' => $item]);
                    } elseif ($item instanceof CalendarEventIF) {
                        $result[] = $item;
                    }

                }
            }
        }

        $calendarEntries = CalendarEntryQuery::findForFilter($start, $end, $contentContainer, $filters, null, $expand, $types);

        $result = array_merge($calendarEntries, $result);

        ArrayHelper::multisort($result, ['startDateTime', 'endDateTime'], [SORT_ASC, SORT_ASC]);

        return (count($result) > $limit) ? array_slice($result, 0, $limit) : $result;
    }

    public static $containerCache = [];

    public function getEventColor(CalendarEventIF $event)
    {
        if ($event->getColor()) {
            return $event->getColor();
        }

        $type = $event->getEventType();

        if (!$type) {
            return null;
        }

        $typeSettings = null;

        if ($event instanceof ContentActiveRecord) {
            /* @var $content Content */
            $content = $event->content;
            if ($content->contentcontainer_id === null) {
                $typeSettings = $this->getItemType($type->getKey());
            } else {
                $container = static::$containerCache[$content->contentcontainer_id] ?? $content->container;
                $typeSettings = $this->getItemType($type->getKey(), $container);
            }
        }

        return $typeSettings ? $typeSettings->getColor() : $type->getDefaultColor();
    }

    /**
     * @param ContentContainerActiveRecord|null $contentContainer
     * @param int $daysInFuture
     * @param int $limit
     * @param array $filters
     * @param bool $expand
     * @return CalendarEventIF[]
     * @throws \Throwable
     */
    public function getUpcomingEntries(?ContentContainerActiveRecord $contentContainer = null, $daysInFuture = 7, $limit = 5, $filters = [], $expand = true)
    {
        $start = new DateTime('now', CalendarUtils::getUserTimeZone());
        $end = ($daysInFuture > 0) ? (new DateTime('now', CalendarUtils::getUserTimeZone()))
                ->add(new DateInterval('P' . $daysInFuture . 'D')) : null;

        return $this->getCalendarItems($start, $end, $filters, $contentContainer, $limit, $expand);
    }

    /**
     * @param string $key item key
     * @param ContentContainerActiveRecord|null $contentContainer
     * @return CalendarTypeSetting|null
     */
    public function getItemType($key, ?ContentContainerActiveRecord $contentContainer = null)
    {
        $itemTypes = $this->getCalendarItemTypes($contentContainer);
        foreach ($itemTypes as $itemType) {
            if ($itemType->key === $key) {
                return $itemType;
            }
        }

        return null;
    }
}
