<?php

namespace humhub\modules\animal_management\services;

use humhub\modules\animal_management\models\Animal;
use humhub\modules\animal_management\models\AnimalGalleryItem;
use humhub\modules\animal_management\models\AnimalGalleryLink;
use humhub\modules\gallery\models\CustomGallery;
use humhub\modules\space\models\Space;
use Yii;

class GalleryIntegrationService
{
    public static function canSyncForSpace(Space $space): bool
    {
        if (!$space->moduleManager->isEnabled('animal_management')) {
            return false;
        }

        if (!$space->moduleManager->isEnabled('gallery')) {
            return false;
        }

        return self::hasRequiredTables();
    }

    public static function syncSpaceAnimalGalleries(Space $space): void
    {
        if (!self::canSyncForSpace($space)) {
            return;
        }

        $animals = Animal::find()->where(['contentcontainer_id' => (int)$space->contentcontainer_id])->all();
        $synced = 0;
        foreach ($animals as $animal) {
            if ($animal instanceof Animal) {
                if (self::ensureAnimalGallery($animal, $space) instanceof CustomGallery) {
                    $synced++;
                }
            }
        }

        Yii::warning([
            'space_id' => (int)$space->id,
            'contentcontainer_id' => (int)$space->contentcontainer_id,
            'animal_count' => count($animals),
            'synced_count' => $synced,
            'has_link_table' => self::hasLinkTable(),
        ], 'animal_management.gallery_integration.sync');
    }

    public static function ensureAnimalGallery(Animal $animal, ?Space $space = null): ?CustomGallery
    {
        if (!self::hasRequiredTables()) {
            return null;
        }

        $space = $space ?: Space::findOne(['contentcontainer_id' => (int)$animal->contentcontainer_id]);
        if (!$space instanceof Space || !self::canSyncForSpace($space)) {
            return null;
        }

        $link = self::hasLinkTable() ? AnimalGalleryLink::findOne(['animal_id' => (int)$animal->id]) : null;
        $gallery = null;

        if ($link instanceof AnimalGalleryLink) {
            $gallery = CustomGallery::find()
                ->contentContainer($space)
                ->where(['gallery_gallery.id' => (int)$link->gallery_id])
                ->one();
        }

        if (!$gallery instanceof CustomGallery) {
            $gallery = CustomGallery::find()
                ->contentContainer($space)
                ->where(['like', 'description', self::buildMarker((int)$animal->id)])
                ->one();

            if (!$gallery instanceof CustomGallery) {
                $gallery = CustomGallery::find()
                    ->contentContainer($space)
                    ->where(['title' => self::buildTitle($animal)])
                    ->one();
            }
        }

        if (!$gallery instanceof CustomGallery) {
            $gallery = new CustomGallery();
            $gallery->content->container = $space;
            $gallery->content->visibility = (int)$space->getDefaultContentVisibility();
            $gallery->title = self::buildTitle($animal);
            $gallery->description = self::buildDescription($animal);

            try {
                if (!$gallery->save()) {
                    Yii::warning($gallery->getErrors(), 'animal_management.gallery_integration.gallery_create_failed');
                    return null;
                }
            } catch (\Throwable $e) {
                Yii::warning($e->getMessage(), 'animal_management.gallery_integration.gallery_create_failed');
                return null;
            }
        } else {
            $newTitle = self::buildTitle($animal);
            $newDescription = self::buildDescription($animal);
            $dirty = false;

            if ((string)$gallery->title !== $newTitle) {
                $gallery->title = $newTitle;
                $dirty = true;
            }

            if ((string)$gallery->description !== $newDescription) {
                $gallery->description = $newDescription;
                $dirty = true;
            }

            if ($dirty) {
                try {
                    $gallery->save();
                } catch (\Throwable $e) {
                    Yii::warning($e->getMessage(), 'animal_management.gallery_integration.gallery_update_failed');
                }
            }
        }

        if (self::hasLinkTable()) {
            if (!$link instanceof AnimalGalleryLink) {
                $link = new AnimalGalleryLink();
                $link->animal_id = (int)$animal->id;
            }

            $link->gallery_id = (int)$gallery->id;
            $link->contentcontainer_id = (int)$space->contentcontainer_id;
            try {
                if (!$link->save()) {
                    Yii::warning($link->getErrors(), 'animal_management.gallery_integration.link_save_failed');
                }
            } catch (\Throwable $e) {
                Yii::warning($e->getMessage(), 'animal_management.gallery_integration.link_save_failed');
            }
        }

        self::refreshGalleryThumb($animal, $gallery);
        return $gallery;
    }

    public static function isAnimalBackedGallery(CustomGallery $gallery): bool
    {
        return self::getAnimalByGalleryId((int)$gallery->id) instanceof Animal;
    }

    public static function getAnimalByGalleryId(int $galleryId): ?Animal
    {
        if (!self::hasRequiredTables()) {
            return null;
        }

        if (self::hasLinkTable()) {
            $link = AnimalGalleryLink::findOne(['gallery_id' => $galleryId]);
            if ($link instanceof AnimalGalleryLink) {
                return Animal::findOne(['id' => (int)$link->animal_id]);
            }
        }

        $gallery = CustomGallery::findOne(['id' => $galleryId]);
        if (!$gallery instanceof CustomGallery) {
            return null;
        }

        $animalId = self::extractAnimalIdFromDescription((string)$gallery->description);
        if ($animalId === null) {
            $animalId = self::extractAnimalIdFromTitle($gallery);
            if ($animalId === null) {
                return null;
            }
        }

        return Animal::findOne(['id' => $animalId]);
    }

    public static function getAnimalItemsQuery(CustomGallery $gallery)
    {
        $animal = self::getAnimalByGalleryId((int)$gallery->id);
        if (!$animal instanceof Animal) {
            Yii::warning([
                'gallery_id' => (int)$gallery->id,
                'title' => (string)$gallery->title,
                'description' => (string)$gallery->description,
            ], 'animal_management.gallery_integration.gallery_unmapped');
            return null;
        }

        return AnimalGalleryItem::find()
            ->where(['animal_id' => (int)$animal->id])
            ->andWhere([
                'or',
                ['and', ['not', ['file_path' => null]], ['!=', 'file_path', '']],
                ['not', ['file_id' => null]],
            ])
            ->orderBy(['id' => SORT_DESC]);
    }

    public static function getAnimalPreviewUrl(CustomGallery $gallery): ?string
    {
        $animal = self::getAnimalByGalleryId((int)$gallery->id);
        if (!$animal instanceof Animal) {
            return null;
        }

        $item = AnimalGalleryItem::find()
            ->where(['animal_id' => (int)$animal->id])
            ->orderBy(['id' => SORT_DESC])
            ->one();

        if (!$item instanceof AnimalGalleryItem) {
            return null;
        }

        $url = trim((string)$item->getImageUrl());
        return $url !== '' ? $url : null;
    }

    public static function isAnimalGalleryEmpty(CustomGallery $gallery): ?bool
    {
        $animal = self::getAnimalByGalleryId((int)$gallery->id);
        if (!$animal instanceof Animal) {
            return null;
        }

        return !AnimalGalleryItem::find()->where(['animal_id' => (int)$animal->id])->exists();
    }

    private static function refreshGalleryThumb(Animal $animal, CustomGallery $gallery): void
    {
        $thumbFileId = AnimalGalleryItem::find()
            ->where(['animal_id' => (int)$animal->id])
            ->andWhere(['not', ['file_id' => null]])
            ->orderBy(['id' => SORT_DESC])
            ->select('file_id')
            ->scalar();

        $thumbFileId = $thumbFileId === null ? null : (int)$thumbFileId;
        if ((int)($gallery->thumb_file_id ?? 0) === (int)($thumbFileId ?? 0)) {
            return;
        }

        $gallery->thumb_file_id = $thumbFileId;
        $gallery->save(false, ['thumb_file_id']);
    }

    private static function hasRequiredTables(): bool
    {
        $schema = Yii::$app->db->schema;

        return $schema->getTableSchema('rescue_animal', true) !== null
            && $schema->getTableSchema('rescue_animal_gallery_item', true) !== null
            && $schema->getTableSchema('gallery_gallery', true) !== null;
    }

    private static function hasLinkTable(): bool
    {
        return Yii::$app->db->schema->getTableSchema('rescue_animal_gallery_link', true) !== null;
    }

    private static function buildTitle(Animal $animal): string
    {
        return $animal->getDisplayName() . ' Gallery';
    }

    private static function buildDescription(Animal $animal): string
    {
        return self::buildMarker((int)$animal->id);
    }

    private static function buildMarker(int $animalId): string
    {
        return '[animal-gallery:' . $animalId . ']';
    }

    private static function extractAnimalIdFromDescription(string $description): ?int
    {
        if (!preg_match('/\[animal-gallery:(\d+)\]/', $description, $matches)) {
            return null;
        }

        return isset($matches[1]) ? (int)$matches[1] : null;
    }

    private static function extractAnimalIdFromTitle(CustomGallery $gallery): ?int
    {
        $container = $gallery->content->container ?? null;
        if (!$container instanceof Space) {
            return null;
        }

        $title = trim((string)$gallery->title);
        if ($title === '') {
            return null;
        }

        $titleNormalized = self::normalizeTitleToken($title);
        if ($titleNormalized === '') {
            return null;
        }

        $animals = Animal::find()
            ->where(['contentcontainer_id' => (int)$container->contentcontainer_id])
            ->orderBy(['id' => SORT_ASC])
            ->all();

        foreach ($animals as $animal) {
            if (!$animal instanceof Animal) {
                continue;
            }

            $nameNormalized = self::normalizeTitleToken((string)$animal->name);
            if ($nameNormalized !== '' && ($nameNormalized === $titleNormalized || strpos($titleNormalized, $nameNormalized) !== false)) {
                return (int)$animal->id;
            }

            $uidNormalized = self::normalizeTitleToken((string)$animal->animal_uid);
            if ($uidNormalized !== '' && ($uidNormalized === $titleNormalized || strpos($titleNormalized, $uidNormalized) !== false)) {
                return (int)$animal->id;
            }
        }

        return null;
    }

    private static function normalizeTitleToken(string $value): string
    {
        $value = strtolower(trim($value));
        if ($value === '') {
            return '';
        }

        $value = preg_replace('/\bgallery\b/i', ' ', $value);
        $value = preg_replace('/[^a-z0-9]+/i', ' ', (string)$value);
        return trim((string)$value);
    }

}