<?php

namespace Chill\MainBundle\CRUD\Controller;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Annotation\Route;
use Symfony\Component\Serializer\SerializerInterface;
use Chill\MainBundle\Serializer\Model\Collection;
use Chill\MainBundle\Pagination\PaginatorInterface;

class ApiController extends AbstractCRUDController
{
    /**
     * The view action.
     * 
     * Some steps may be overriden during this process of rendering:
     * 
     * This method:
     * 
     * 1.  fetch the entity, using `getEntity`
     * 2.  launch `onPostFetchEntity`. If postfetch is an instance of Response,
     *     this response is returned.
     * 2.  throw an HttpNotFoundException if entity is null
     * 3.  check ACL using `checkACL` ;
     * 4.  launch `onPostCheckACL`. If the result is an instance of Response, 
     *     this response is returned ;
     * 5.  Serialize the entity and return the result. The serialization context is given by `getSerializationContext`
     * 
     */
    protected function entityGet(string $action, Request $request, $id, $_format = 'html'): Response
    {
        $entity = $this->getEntity($action, $id, $request, $_format);
        
        $postFetch = $this->onPostFetchEntity($action, $request, $entity, $_format);
        
        if ($postFetch instanceof Response) {
            return $postFetch;
        }
        
        if (NULL === $entity) {
            throw $this->createNotFoundException(sprintf("The %s with id %s "
                . "is not found", $this->getCrudName(), $id));
        }
        
        $response = $this->checkACL($action, $request, $_format, $entity);
        if ($response instanceof Response) {
            return $response;
        }
        
        $response = $this->onPostCheckACL($action, $request, $_format, $entity);
        if ($response instanceof Response) {
            return $response;
        }

        $response = $this->onBeforeSerialize($action, $request, $_format, $entity);
        if ($response instanceof Response) {
            return $response;
        }

        if ($_format === 'json') {
            $context = $this->getContextForSerialization($action, $request, $_format, $entity);

            return $this->json($entity, Response::HTTP_OK, [], $context);
        } else {
            throw new \Symfony\Component\HttpFoundation\Exception\BadRequestException("This format is not implemented");
        }
    }

    public function onBeforeSerialize(string $action, Request $request, $_format, $entity): ?Response
    {
        return null;
    }

    /**
     * Base method for handling api action
     *
     * @return void
     */
    public function entityApi(Request $request, $id, $_format): Response
    {
        switch ($request->getMethod()) {
            case Request::METHOD_GET:
            case REQUEST::METHOD_HEAD:
                return $this->entityGet('_entity', $request, $id, $_format);
            default:
                throw new \Symfony\Component\HttpFoundation\Exception\BadRequestException("This method is not implemented");
        }
    }

    /**
     * Base action for indexing entities
     */
    public function indexApi(Request $request, string $_format)
    {
        switch ($request->getMethod()) {
            case Request::METHOD_GET:
            case REQUEST::METHOD_HEAD:
                return $this->indexApiAction('_index', $request, $_format);
            default:
                throw $this->createNotFoundException("This method is not supported");
        }
    }

    /**
     * Build an index page.
     * 
     * Some steps may be overriden during this process of rendering.
     * 
     * This method:
     * 
     * 1.  Launch `onPreIndex`
     * x.  check acl. If it does return a response instance, return it
     * x.  launch `onPostCheckACL`. If it does return a response instance, return it
     * 1.  count the items, using `countEntities`
     * 2.  build a paginator element from the the number of entities ;
     * 3.  Launch `onPreIndexQuery`. If it does return a response instance, return it
     * 3.  build a query, using `queryEntities`
     * x.  fetch the results, using `getQueryResult`
     * x.  Launch `onPostIndexFetchQuery`. If it does return a response instance, return it
     * 4.  Serialize the entities in a Collection, using `SerializeCollection`
     * 
     * @param string $action
     * @param Request $request
     * @return type
     */
    protected function indexApiAction($action, Request $request, $_format)
    {
        $this->onPreIndex($action, $request, $_format);
        
        $response = $this->checkACL($action, $request, $_format);
        if ($response instanceof Response) {
            return $response;
        }
        
        if (!isset($entity)) {
            $entity = '';
        }
        
        $response = $this->onPostCheckACL($action, $request, $_format, $entity);
        if ($response instanceof Response) {
            return $response;
        }
        
        $totalItems = $this->countEntities($action, $request, $_format);
        $paginator = $this->getPaginatorFactory()->create($totalItems);
        
        $response = $this->onPreIndexBuildQuery($action, $request, $_format, $totalItems, 
            $paginator);
        
        if ($response instanceof Response) {
            return $response;
        }
        
        $query = $this->queryEntities($action, $request, $_format, $paginator);
        
        $response = $this->onPostIndexBuildQuery($action, $request, $_format, $totalItems, 
            $paginator, $query);
        
        if ($response instanceof Response) {
            return $response;
        }
        
        $entities = $this->getQueryResult($action, $request, $_format, $totalItems, $paginator, $query);
        
        $response = $this->onPostIndexFetchQuery($action, $request, $_format, $totalItems, 
            $paginator, $entities);
        
        if ($response instanceof Response) {
            return $response;
        }
        
        return $this->serializeCollection($action, $request, $_format, $paginator, $entities);    
    }
    
    /**
     * Serialize collections
     *
     */
    protected function serializeCollection(string $action, Request $request, string $_format, PaginatorInterface $paginator, $entities): Response
    {
        $model = new Collection($entities, $paginator);

        $context = $this->getContextForSerialization($action, $request, $_format, $entities);

        return $this->json($model, Response::HTTP_OK, [], $context);
    }
    

    protected function getContextForSerialization(string $action, Request $request, string $_format, $entity): array
    {
        return [];
    }

    /**
     * get the role given from the config.
     */
    protected function getRoleFor(string $action, Request $request, $entity, $_format): string
    {
        $actionConfig = $this->getActionConfig($action);

        if (NULL !== $actionConfig['roles'][$request->getMethod()]) {
            return $actionConfig['roles'][$request->getMethod()];
        }

        if ($this->crudConfig['base_role']) {
            return $this->crudConfig['base_role'];
        }

        throw new \RuntimeException(sprintf("the config does not have any role for the ".
            "method %s nor a global role for the whole action. Add those to your ".
            "configuration or override the required method", $request->getMethod()));
        
    }

    protected function getSerializer(): SerializerInterface
    {
        return $this->get('serializer');
    }
}