<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Contracts\Foundation\Application;
use Illuminate\Foundation\Http\MaintenanceModeBypassCookie;
use Symfony\Component\HttpKernel\Exception\HttpException;

class PreventRequestsDuringMaintenance
{
    /**
     * The application implementation.
     *
     * @var \Illuminate\Contracts\Foundation\Application
     */
    protected $app;

    /**
     * The URIs that should be accessible while maintenance mode is enabled.
     *
     * @var array
     */
    protected $except = ['banners/data', 'maintenance/bypass'];

    /**
     * Create a new middleware instance.
     *
     * @param  \Illuminate\Contracts\Foundation\Application  $app
     * @return void
     */
    public function __construct(Application $app)
    {
        $this->app = $app;
    }

    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     *
     * @throws \Symfony\Component\HttpKernel\Exception\HttpException
     */
    public function handle($request, Closure $next)
    {
        if ($this->app->isDownForMaintenance()) {
            $data = json_decode(file_get_contents($this->app->storagePath().'/framework/down'), true);
			
            if ($this->hasValidBypassCookie($request, $data) ||
                $this->inExceptArray($request)) {
                return $next($request);
            }
	
            return response('{"errors":[{"code":503,"message":"ServiceUnavailable"}]}', 503)
				->header('Cache-Control', 'private')
				->header('Content-Type', 'application/json; charset=utf-8');
        }

        return $next($request);
    }

    /**
     * Determine if the incoming request has a maintenance mode bypass cookie.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  array  $data
     * @return bool
     */
    protected function hasValidBypassCookie($request, array $data)
    {
        return isset($data['secret']) &&
                $request->cookie('gt_constraint') &&
                MaintenanceModeBypassCookie::isValid(
                    $request->cookie('gt_constraint'),
                    $data['secret']
                );
    }

    /**
     * Determine if the request has a URI that should be accessible in maintenance mode.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return bool
     */
    protected function inExceptArray($request)
    {
        foreach ($this->except as $except) {
            if ($except !== '/') {
                $except = trim($except, '/');
            }

            if ($request->fullUrlIs($except) || $request->is($except)) {
                return true;
            }
        }

        return false;
    }

    /**
     * Redirect the user back to the root of the application with a maintenance mode bypass cookie.
     *
     * @param  string  $secret
     * @return \Illuminate\Http\RedirectResponse
     */
    protected function bypassResponse(string $secret)
    {
        return redirect('/')->withCookie(
            MaintenanceModeBypassCookie::create($secret)
        );
    }

    /**
     * Get the headers that should be sent with the response.
     *
     * @param  array  $data
     * @return array
     */
    protected function getHeaders($data)
    {
        $headers = isset($data['retry']) ? ['Retry-After' => $data['retry']] : [];

        if (isset($data['refresh'])) {
            $headers['Refresh'] = $data['refresh'];
        }

        return $headers;
    }

    /**
     * Get the URIs that should be accessible even when maintenance mode is enabled.
     *
     * @return array
     */
    public function getExcludedPaths()
    {
        return $this->except;
    }
}