<?php

namespace App\Http\Controllers\Pos;

use App\Http\Controllers\Controller;
use App\Http\Controllers\Pos\Concerns\ScopesToAccount;
use App\Models\PosSaleLine;
use App\Services\Pos\KitchenBoardService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\View\View;
use Symfony\Component\HttpFoundation\StreamedResponse;

class KitchenController extends Controller
{
    use ScopesToAccount;

    public function __construct(private KitchenBoardService $board) {}

    public function index(Request $request): View
    {
        return view('pos.kitchen.index', [
            'stations' => $this->board->stations($this->ownerRef($request)),
        ]);
    }

    /**
     * Active kitchen tickets — open sales with fired-but-not-served lines.
     * Used for the initial load and as a fallback when SSE is unavailable.
     */
    public function feed(Request $request): JsonResponse
    {
        return response()->json($this->board->payload($this->ownerRef($request)));
    }

    /**
     * Realtime feed over Server-Sent Events. Pushes the board whenever it
     * changes (~1s tick), with a heartbeat. Bounded lifetime so PHP-FPM workers
     * recycle — the browser's EventSource reconnects automatically.
     */
    public function stream(Request $request): StreamedResponse
    {
        $owner = $this->ownerRef($request);
        // Release the session lock early (DB driver doesn't lock, but be safe).
        $request->session()->save();

        $response = new StreamedResponse(function () use ($owner) {
            while (ob_get_level() > 0) {
                @ob_end_flush();
            }
            @set_time_limit(0);

            $start = time();
            $lastHash = null;

            while (true) {
                $payload = $this->board->payload($owner);
                $json = json_encode($payload);
                $hash = md5((string) $json);

                if ($hash !== $lastHash) {
                    echo 'data: '.$json."\n\n";
                    $lastHash = $hash;
                } else {
                    echo ": ping\n\n"; // heartbeat
                }
                @ob_flush();
                @flush();

                if (connection_aborted() || (time() - $start) >= 25) {
                    break;
                }
                sleep(1);
            }
        });

        $response->headers->set('Content-Type', 'text/event-stream');
        $response->headers->set('Cache-Control', 'no-cache');
        $response->headers->set('Connection', 'keep-alive');
        $response->headers->set('X-Accel-Buffering', 'no'); // disable nginx buffering

        return $response;
    }

    /**
     * Advance one line to the next kitchen state (queued → preparing → ready → served).
     */
    public function bump(Request $request, PosSaleLine $line): JsonResponse
    {
        return response()->json($this->board->bumpLine($line, $this->ownerRef($request)));
    }
}