Backpack\CRUD\app\Library\CrudPanel\Traits\Relationships

Complexity

Total Complexity

40

Size/Duplication

Total Lines	205
Duplicated Lines	0 %

Importance

Changes	6
Bugs	2	Features	0

10 Methods

Rating	Name	Duplication	Size	Complexity
B	getRelationInstance()	0	30	7
A	inferRelationTypeFromRelationship()	0	5	1
A	parseRelationFieldNamesFromHtml()	0	17	6
A	getFieldsWithRelationType()	0	13	3
A	inferFieldModelFromRelationship()	0	5	1
B	inferFieldTypeFromFieldRelation()	0	12	7
A	guessIfFieldHasPivotFromRelationType()	0	10	3
B	guessIfFieldHasMultipleFromRelationType()	0	13	8
A	isNestedRelation()	0	3	1
A	getOnlyRelationEntity()	0	10	3

<?php

namespace Backpack\CRUD\app\Library\CrudPanel\Traits;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Arr;
use Illuminate\Support\Str;

trait Relationships
{
    /**
     * From the field entity we get the relation instance.
     *
     * @param array $entity
     * @return object
     */
    public function getRelationInstance($field)
    {
        $entity = $this->getOnlyRelationEntity($field);
        $entity_array = explode('.', $entity);
        $relation_model = $this->getRelationModel($entity);

The method getRelationModel() does not exist on Backpack\CRUD\app\Library\CrudPanel\Traits\Relationships. Did you maybe mean getRelationInstance()?

        $related_method = Arr::last($entity_array);
        if (count(explode('.', $entity)) == count(explode('.', $field['entity']))) {
            $relation_model = $this->getRelationModel($entity, -1);
        }
        $relation_model = new $relation_model();

        // if counts are diferent means that last element of entity is the field in relation.
        if (count(explode('.', $entity)) != count(explode('.', $field['entity']))) {
            if (in_array($related_method, $relation_model->getFillable())) {
                if (count($entity_array) > 1) {
                    $related_method = $entity_array[(count($entity_array) - 2)];
                    $relation_model = $this->getRelationModel($entity, -2);
                } else {
                    $relation_model = $this->model;
                }
            }
        }
        if (count($entity_array) == 1) {
            if (method_exists($this->model, $related_method)) {
                return $this->model->{$related_method}();
            }
        }

        return $relation_model->{$related_method}();
    }

    /**
     * Get the fields for relationships, according to the relation type. It looks only for direct
     * relations - it will NOT look through relationships of relationships.
     *
     * @param string|array $relation_types Eloquent relation class or array of Eloquent relation classes. Eg: BelongsTo
     *
     * @return array The fields with corresponding relation types.
     */
    public function getFieldsWithRelationType($relation_types): array
    {
        $relation_types = (array) $relation_types;

        return collect($this->fields())

It seems like fields() must be provided by classes using this trait. How about adding it as abstract method to this trait?

            ->where('model')
            ->whereIn('relation_type', $relation_types)
            ->filter(function ($item) {
                $related_model = get_class($this->model->{Str::before($item['entity'], '.')}()->getRelated());

                return Str::contains($item['entity'], '.') && $item['model'] !== $related_model ? false : true;
            })
            ->toArray();
    }

    /**
     * Grabs an relation instance and returns the class name of the related model.
     *
     * @param array $field
     * @return string
     */
    public function inferFieldModelFromRelationship($field)
    {
        $relation = $this->getRelationInstance($field);

        return get_class($relation->getRelated());
    }

    /**
     * Return the relation type from a given field: BelongsTo, HasOne ... etc.
     *
     * @param array $field
     * @return string
     */
    public function inferRelationTypeFromRelationship($field)
    {
        $relation = $this->getRelationInstance($field);

        return Arr::last(explode('\\', get_class($relation)));
    }

    /**
     * Parse the field name back to the related entity after the form is submited.
     * Its called in getAllFieldNames().
     *
     * @param array $fields
     * @return array
     */
    public function parseRelationFieldNamesFromHtml($fields)
    {
        foreach ($fields as &$field) {
            // we only want to parse fields that has a relation type and their name contains [ ] used in html.
            if (isset($field['relation_type']) && preg_match('/[\[\]]/', $field['name']) !== 0) {
                $chunks = explode('[', $field['name']);

                foreach ($chunks as &$chunk) {
                    if (strpos($chunk, ']')) {
                        $chunk = str_replace(']', '', $chunk);
                    }
                }
                $field['name'] = implode('.', $chunks);
            }
        }

        return $fields;
    }

    /**
     * Based on relation type returns the default field type.
     *
     * @param string $relation_type
     * @return string
     */
    public function inferFieldTypeFromFieldRelation($field)
    {
        switch ($field['relation_type']) {
            case 'BelongsToMany':
            case 'HasMany':
            case 'HasManyThrough':
            case 'MorphMany':
            case 'MorphToMany':
            case 'BelongsTo':
                return 'relationship';
            default:
                return 'text';
        }
    }

    /**
     * Based on relation type returns if relation allows multiple entities.
     *
     * @param string $relation_type
     * @return bool
     */
    public function guessIfFieldHasMultipleFromRelationType($relation_type)
    {
        switch ($relation_type) {
            case 'BelongsToMany':
            case 'HasMany':
            case 'HasManyThrough':
            case 'HasOneOrMany':
            case 'MorphMany':
            case 'MorphOneOrMany':
            case 'MorphToMany':
                return true;
            default:
                return false;
        }
    }

    /**
     * Based on relation type returns if relation has a pivot table.
     *
     * @param string $relation_type
     * @return bool
     */
    public function guessIfFieldHasPivotFromRelationType($relation_type)
    {
        switch ($relation_type) {
            case 'BelongsToMany':
            case 'MorphToMany':
                return true;
                break;

break is not strictly necessary here and could be removed.

            default:
                return false;
                break;
        }
    }

    /**
     * Check if field name contains a dot, if so, meaning it's a nested relation.
     *
     * @param array $field
     * @return bool
     */
    protected function isNestedRelation($field): bool
    {
        return Str::contains($field['entity'], '.');
    }

    /**
     * Return the relation without any model attributes there.
     * Eg. user.entity_id would return user, as entity_id is not a relation in user.
     *
     * @param array $relation_field
     * @return string
     */
    public function getOnlyRelationEntity($relation_field)
    {
        $relation_model = $this->getRelationModel($relation_field['entity'], -1);
        $related_method = Str::afterLast($relation_field['entity'], '.');

        if (! method_exists($relation_model, $related_method) && $this->isNestedRelation($relation_field)) {
            return Str::beforeLast($relation_field['entity'], '.');
        }

        return $relation_field['entity'];
    }
}