<?php
// SPDX-License-Identifier: EUPL-1.2
// Authors: see README.md

use SeaCMS\Api\BadMethodException;
use SeaCMS\Api\JsonResponse;
use SeaCMS\Api\NotFoundRouteException;

/**
 * An api plugin for Pico 3.
 */
class SeacmsApi extends AbstractPicoPlugin
{
    /**
     * Pico API version.
     * @var int
     */
    const API_VERSION = 3;

    /**
     * routes trigerred OnPageRendered
     * @var array
     */
    protected $routesOnPageRendered ;

    /**
     * return api routes
     * @return array
     */
    public function registerOnPageRenderedApiRoutes():array
    {
        return [
            'POST test' => 'api',
            'GET test/(.*)' => 'apiWithText',
        ];
    }

    /**
     * method for api
     * @return JsonResponse
     */
    public function api(): JsonResponse
    {
        return new JsonResponse(200,['test'=>'OK']);
    }

    /**
     * method for api
     * @param string $text
     * @return JsonResponse
     */
    public function apiWithText(string $text): JsonResponse
    {
        return new JsonResponse(200,['text'=>$text]);
    }

    /**
     * Triggered after Pico has loaded all available plugins
     *
     * This event is triggered nevertheless the plugin is enabled or not.
     * It is NOT guaranteed that plugin dependencies are fulfilled!
     *
     *
     * @param object[] $plugins loaded plugin instances
     */
    public function onPluginsLoaded(array $plugins)
    {
        $this->routesOnPageRendered = [];
        foreach($plugins as $plugin){
            if (method_exists($plugin,'registerOnPageRenderedApiRoutes')){
                $routes = $plugin->registerOnPageRenderedApiRoutes();
                if (is_array($routes)){
                    foreach($routes as $route => $methodName){
                        if (is_string($methodName) && method_exists($plugin,$methodName)){
                            $this->routesOnPageRendered[$route] = [$plugin,$methodName];
                        }
                    }
                }
            }
        }
    }

    /**
     * If the call is a save query, save the edited regions and output the JSON response.
     *
     * Triggered after Pico has rendered the page
     *
     * @param  string &$output contents which will be sent to the user
     * @return void
     */
    public function onPageRendered(&$output)
    {
        if (isset($_GET['api'])){
            $route = $this->getPico()->getUrlParameter(
                'api',
                FILTER_UNSAFE_RAW,
                [
                    'default' => ''
                ],
                [
                    FILTER_FLAG_STRIP_LOW,
                    FILTER_FLAG_STRIP_HIGH
                ]
            );
            $route = trim($route);
            if (empty($route)){
                $output = (new JsonResponse(404,['code'=>404,'reason'=>'Empty api route']))->send();
            } elseif (!preg_match('/^[A-Za-z0-9_\-.\/]+$/',$route)) {
                $output = (new JsonResponse(404,['code'=>404,'reason'=>"Route '$route' use forbidden characters !"]))->send();
            } else {
                ob_start();
                $response = null;
                try {
                    $data = $this->searchCorrespondingRoute($route);
                    $response = call_user_func_array([$data['plugin'],$data['methodName']],$data['params']);
                    if (!($response instanceof JsonResponse)){
                        $response = null;
                        throw new Exception("Return of '{$data['methodName']}' should be instanceof of 'JsonResponse'");
                    }
                } catch (BadMethodException $th) {
                    $code = 405;
                    $content = ['reason'=>$th->getMessage()];
                } catch (NotFoundRouteException $th) {
                    $code = 404;
                    $content = ['reason'=>"Route '$route' not found !"];
                } catch (Throwable $th) {
                    $code = 500;
                    $content = ['reason'=>$th->__toString()];
                }
                $rawOutput = ob_get_contents();
                ob_end_clean();
                if (empty($response)){
                    if (!empty($rawOutput)){
                        $content['rawOutput'] = $rawOutput;
                    }
                    $content = array_merge(['code'=>$code],$content);
                    $response = (new JsonResponse($code,$content));
                } elseif (!empty($rawOutput)) {
                    $response->mergeInContent(compact(['rawOutput']));
                }
                $output = $response->send();
            }
        }
    }

    /**
     * search corresponding route 
     * @param string $route
     * @return array ['plugin'=>$plugin,'methodName'=>string,'params'=>array]
     * @throws BadMethodException
     * @throws NotFoundRouteException
     */
    protected function searchCorrespondingRoute(string $route): array
    {
        if (empty($_SERVER['REQUEST_METHOD'])){
            throw new BadMethodException('Method not defined');
        }
        $method = $_SERVER['REQUEST_METHOD'];
        if (!in_array($method,['GET','POST'],true)){
            throw new BadMethodException('Not allowed method');
        }
        $splittedRoute = explode('/',$route);
        
        $nb = count($splittedRoute);
        $badMethod = false;
        for ($i=0; $i < 2**$nb; $i++) {
            $params = [];
            $splittedRouteFiltered = [];
            foreach ($splittedRoute as $idx => $value) {
                $currentPower = $nb - $idx - 1 ;
                if ((2**$currentPower & $i) > 0){
                    $splittedRouteFiltered[] = '(.*)';
                    $params[] = $value;
                } else {
                    $splittedRouteFiltered[] = $value;
                }
            }
            $searchingRoute = implode('/',$splittedRouteFiltered);
            $data = [];
            if (array_key_exists("$method $searchingRoute",$this->routesOnPageRendered)){
                $data = $this->routesOnPageRendered["$method $searchingRoute"];
            } elseif (array_key_exists("$searchingRoute",$this->routesOnPageRendered)){
                $data = $this->routesOnPageRendered["$searchingRoute"];
            }
            if (!empty($data)){
                return [
                    'plugin' => $data[0],
                    'methodName' => $data[1],
                    'params' => $params
                ];
            } elseif (!$badMethod && array_key_exists((($method == 'GET') ? 'POST' : 'GET' )." $searchingRoute",$this->routesOnPageRendered)){
                $badMethod = true;
            }
        }
        if ($badMethod){
            throw new BadMethodException('Not allowed method');
        }
        throw new NotFoundRouteException('');
    }
}