<?php

namespace Lean\Api\Form;

use CSLSJ\Lean\Form\Session\EmailContext;
use Picea\Ui\Method\{ FormContextInterface, };

use Lean\Api\Attribute\ContextField;
use Lean\Api\Exception\MandatoryFieldException;
use Notes\Common\ReflectedProperty;
use Notes\ObjectReflection;
use Ulmus\Attribute\Property\Field;
use Lean\Api\Attribute\EntityField;

use Ulmus\Entity\EntityInterface;
use Ulmus\Entity\Field\Datetime;

abstract class Save extends Form implements \Picea\Ui\Method\FormInterface {

    protected array $reflectedProperties;

    protected string $contextClass;

    public function initialize(FormContextInterface $context) : void
    {
        if ( ! $this->getEntity()->isLoaded() || $context->formSent() ) {
            if (method_exists($context, 'initializeEntity')) {
                $context->initializeEntity($this->getEntity());
            }
            else {
                $this->assignContextToEntity($context);
            }
        }

        parent::initialize($context);
    }

    public function validate(FormContextInterface $context) : bool
    {
        # Context validates ContextField attributes containing properties on empty entity
        $this->validateContextFields($context);

        return $context->valid($this->getEntity()->isLoaded() ? $this->getEntity() : null);
    }

    public function execute(FormContextInterface $context) : mixed
    {
        $entity = $this->getEntity();

        if  ($entity->isLoaded()) {
            if (property_exists($entity, 'updatedAt') && $entity->repository()->generateDatasetDiff($entity) ) {
                $entity->updatedAt = new Datetime();
            }
        }
        else {
            if (property_exists($entity, 'createdAt') && empty($entity->createdAt)) {
                $entity->createdAt = new Datetime();
            }
        }

        try {
            $this->assignContextToEntity($context);

            if ( $saved = $entity::repository()->save($entity) ) {
                $context->pushMessage($this->message::generateSuccess(
                    $this->lang('lean.api.form.save.success.save')
                ));
            }
            else {
                $context->pushMessage($this->message::generateWarning(
                    $this->lang('lean.api.form.save.warning.entity', [ 'entity' => substr($this->entity::class, strrpos($this->entity::class, '\\') + 1) ])
                ));
            }
        }
        catch(\PDOException $ex) {
            throw new \PDOException($this->lang('lean.api.form.save.error.pdo', [ 'error' => $ex->getMessage() ]));
        }
        catch(\Throwable $ex) {
            throw $ex;
        }

        return $saved;
    }

    protected function validateContextFields(FormContextInterface $context) : void
    {
        foreach ($this->reflectedProperties($context) as $name => $property) {
            $attribute = $property->getAttribute(ContextField::class);

            if ($attribute) {
                try {
                    $attribute->object->assertValueSpecs($context->$name ?? null, $this->getEntity()->isLoaded());
                } catch (MandatoryFieldException $e) {
                    throw new MandatoryFieldException("An error occured with field '$name': " . $e->getMessage());
                }
            }
        }
    }

    protected function assignContextToEntity(FormContextInterface $context) : void
    {
        $entity = $this->getEntity();

        foreach($entity::resolveEntity()->fieldList() as $key => $property) {
            $field = $property->getAttribute(Field::class)->object;

            if (! $field->readonly || ! $entity->isLoaded()) {

                $apiField = $property->getAttribute(EntityField::class)->object ?? null;

                if ($apiField) {
                    $var = $apiField->field ?: $key;

                    if ( property_exists($context, $var) && ( new \ReflectionProperty($context, $var) )->isInitialized($context) ) {
                        if ($apiField->setterMethod) {
                            # Use a setter method
                            call_user_func([ $entity, $apiField->setterMethod ], $context->{$var});
                        }
                        else {
                            # Direct property set
                            $entity->$key = $context->{$var};
                        }
                    }
                    elseif (! $entity->isLoaded()) {
                        # Applies 'default' value assigned to ContextField property
                        $attr = $this->reflectedProperties($context)[$var] ?? null;

                        if ($attr) {
                            $contextField = $attr->getAttribute(ContextField::class);

                            if ($contextField) {
                                if (isset($contextField->object->default)) {
                                    $entity->$key = $contextField->object->default;
                                }
                            }
                        }
                    }
                }
            }
        }
    }

    private function reflectedProperties(FormContextInterface $context) : array
    {
        $this->reflectedProperties ??= ObjectReflection::fromClass($context::class)->reflectProperties(\ReflectionProperty::IS_PUBLIC);

        return $this->reflectedProperties;
    }
}