<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;

class InvalidatePreviousSessions
{
    /**
     * Session key marking a Softphone integration session.
     */
    const INTEGRATION_SESSION_KEY = 'softphone_integration';

    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure(\Illuminate\Http\Request): (\Illuminate\Http\Response|\Illuminate\Http\RedirectResponse)  $next
     * @return \Illuminate\Http\Response|\Illuminate\Http\RedirectResponse
     */
    public function handle($request, Closure $next)
    {
        if (Auth::check()) {
            // Keep integration sessions alive so the iframe is not logged out.
            if (session()->get(self::INTEGRATION_SESSION_KEY)) {
                return $next($request);
            }

            $currentSessionId = session()->getId();
            $userId = Auth::user()->id;

            // Invalidate all other sessions, keeping integration sessions.
            $otherSessions = DB::table('sessions')
                ->select('id', 'payload')
                ->where('user_id', $userId)
                ->where('id', '!=', $currentSessionId)
                ->get();

            foreach ($otherSessions as $otherSession) {
                if ($this->isIntegrationSession($otherSession->payload)) {
                    continue;
                }

                DB::table('sessions')->where('id', $otherSession->id)->delete();
            }
        }

        return $next($request);
    }

    /**
     * Checks the stored payload for the integration marker.
     */
    protected function isIntegrationSession(?string $payload): bool
    {
        if (empty($payload)) {
            return false;
        }

        $decoded = @unserialize(@base64_decode($payload, true), ['allowed_classes' => false]);

        if (!is_array($decoded)) {
            $json = json_decode((string) $payload, true);
            $decoded = is_array($json) ? $json : null;
        }

        return is_array($decoded) && !empty($decoded[self::INTEGRATION_SESSION_KEY]);
    }
}