Model.php

<?php

namespace ipl\Orm;

use ipl\Orm\Common\PropertiesWithDefaults;
use ipl\Sql\Connection;
use ipl\Sql\ExpressionInterface;

/**
 * Models represent single database tables or parts of it.
 * They are also used to interact with the tables, i.e. in order to query for data.
 */
abstract class Model implements \ArrayAccess, \IteratorAggregate
{
    use PropertiesWithDefaults;

    private $relation;

    public function setRelation(Relation $relation)
    {
        $this->relation = $relation;
    }

    private $nullableProperties;

    final public function __construct(array $properties = null)
    {
        if ($this->hasProperties()) {
            $this->setProperties($properties);
        }

        $this->init();
    }

    /**
     * Get the related database table's name
     *
     * @return string
     */
    abstract public function getTableName();

    /**
     * Get the column name(s) of the primary key
     *
     * @return string|array<string> Array if the primary key is compound, string otherwise
     */
    abstract public function getKeyName();

    /**
     * Get the model's queryable columns
     *
     * @return array<int|string, string|ExpressionInterface>
     */
    abstract public function getColumns();

    /**
     * Get the configured table alias. (Default {@see static::getTableName()})
     *
     * @return string
     */
    public function getTableAlias(): string
    {
        return $this->getTableName();
    }

    /**
     * Get the model's column definitions
     *
     * The array is indexed by column names, values are either strings (labels) or arrays of this format:
     *
     * [
     *  'label' => 'A Column',
     *  'type'  => 'enum(y,n)'
     * ]
     *
     * @return array
     */
    public function getColumnDefinitions()
    {
        return [];
    }

    /**
     * Get a query which is tied to this model and the given database connection
     *
     * @param Connection $db
     *
     * @return Query
     */
    public static function on(Connection $db)
    {
        return (new Query())
            ->setDb($db)
            ->setModel(new static());
    }

    /**
     * Get the model's default sort
     *
     * @return array|string
     */
    public function getDefaultSort()
    {
        return [];
    }

    /**
     * Get the model's search columns
     *
     * @return array
     */
    public function getSearchColumns()
    {
        return [];
    }

    /**
     * Create the model's behaviors
     *
     * @param Behaviors $behaviors
     */
    public function createBehaviors(Behaviors $behaviors)
    {
    }

    /**
     * Create the model's defaults
     *
     * @param Defaults $defaults
     */
    public function createDefaults(Defaults $defaults)
    {
    }

    /**
     * Create the model's relations
     *
     * If your model should be associated to other models, override this method and create the model's relations.
     */
    public function createRelations(Relations $relations)
    {
    }

    /**
     * Initialize the model
     *
     * If you want to adjust the model after construction, override this method.
     */
    protected function init()
    {
    }

    private function nullableColumns()
    {
        if ($this->nullableProperties !== null) {
            return $this->nullableProperties;
        }

        if ($this->relation === null) {
            $this->nullableProperties = (function (): array {
                $ref = new \ReflectionClass($this);
                $doc = $ref->getDocComment();
                preg_match_all('/@property\s+([^\s]+)\s+\$([^\s]+)/', $doc, $matches);
                $cols = [];
                foreach ($matches[1] as $i => $type) {
                    if (strpos($type, '?') === 0 || preg_match('~\|?null\|?~', $type)) {
                        $cols[] = $matches[2][$i];
                    }
                }

                return $cols;
            })();
        } elseif ($this->relation->getJoinType() === 'LEFT') {
            $this->nullableProperties = array_merge($this->getColumns(), (array) $this->getKeyName());
        } else {
            $this->nullableProperties = [];
        }

        return $this->nullableProperties;
    }

    public function __get($key)
    {
        if (in_array($key, $this->nullableColumns(), true)) {
            return null;
        }

        return $this->getProperty($key);
    }

    public function __isset($key)
    {
        if (in_array($key, $this->nullableColumns(), true)) {
            return false;
        }

        return $this->hasProperty($key);
    }
}