<?php

namespace BookStack\References;

use BookStack\Entities\Models\Entity;

use BookStack\Entities\Tools\MixedEntityListLoader;

use BookStack\Permissions\PermissionApplicator;

use Illuminate\Database\Eloquent\Builder;

use Illuminate\Database\Eloquent\Collection;

class ReferenceFetcher

{

public function __construct(

protected PermissionApplicator $permissions,

protected MixedEntityListLoader $mixedEntityListLoader,

) {

}

/**

* Query and return the references pointing to the given entity.

* Loads the commonly required relations while taking permissions into account.

*/

public function getReferencesToEntity(Entity $entity, bool $withContents = false): Collection

{

/** @var Collection<int, Reference> $references */

$references = $this->queryReferencesToEntity($entity)->get();

$this->mixedEntityListLoader->loadIntoRelations($references->all(), 'from', false, $withContents);

return $references;

}

/**

* Returns the count of references pointing to the given entity.

* Takes permissions into account.

*/

public function getReferenceCountToEntity(Entity $entity): int

{

return $this->queryReferencesToEntity($entity)->count();

}

/**

* @return Builder<Reference>

*/

protected function queryReferencesToEntity(Entity $entity): Builder

{

$baseQuery = Reference::query()

->where('to_type', '=', $entity->getMorphClass())

->where('to_id', '=', $entity->id)

->whereHas('from');

return $this->permissions->restrictEntityRelationQuery(

$baseQuery,

'references',

'from_id',

'from_type'

);

}

}