<?php

namespace App\Http\Controllers\Transfer;

use App\Http\Controllers\Controller;
use App\Models\Transfer;
use App\Services\Qr\QrImageGeneratorService;
use App\Services\Qr\QrPdfExporter;
use App\Services\Transfer\TransferRecipientMailService;
use App\Services\Transfer\TransferService;
use App\Services\Upload\ChunkedUploadService;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Str;
use Illuminate\View\View;
use RuntimeException;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\StreamedResponse;

class TransferController extends Controller
{
    public function __construct(
        private TransferService $transfers,
        private ChunkedUploadService $chunkedUploads,
        private QrImageGeneratorService $imageGenerator,
        private QrPdfExporter $pdfExporter,
    ) {}

    public function index(Request $request): View
    {
        $account = ladill_account();

        $transfers = Transfer::query()
            ->where('user_id', $account->id)
            ->accessible()
            ->with(['qrCode', 'files'])
            ->latest()
            ->paginate(20);

        return view('transfer.transfers.index', compact('transfers'));
    }

    public function create(): View
    {
        $mailService = app(TransferRecipientMailService::class);

        return view('transfer.transfers.create', [
            'maxFiles' => (int) config('transfer.max_files_per_transfer', 20),
            'pricePerGb' => (float) config('transfer.price_per_gb_month', 0.30),
            'gracePeriodDays' => (int) config('transfer.grace_period_days', 15),
            'emailMilestones' => $mailService->milestoneOptions(),
            'defaultEmailMilestones' => (array) config('transfer.default_recipient_email_milestones', ['created']),
        ]);
    }

    public function store(Request $request): RedirectResponse
    {
        $account = ladill_account();

        $maxBytes = (int) config('transfer.max_file_bytes', 0);
        $fileRules = ['nullable', 'file'];
        if ($maxBytes > 0) {
            $fileRules[] = 'max:'.(int) ceil($maxBytes / 1024);
        }

        $allowedMilestones = implode(',', app(TransferRecipientMailService::class)->allowedMilestones());

        $data = $request->validate([
            'title' => 'required|string|max:120',
            'message' => 'nullable|string|max:2000',
            'recipient_email' => 'nullable|email|max:255|required_with:email_milestones',
            'email_milestones' => 'nullable|array',
            'email_milestones.*' => 'in:'.$allowedMilestones,
            'password' => 'nullable|string|min:4|max:64',
            'files' => 'nullable|array',
            'files.*' => $fileRules,
            'upload_ids' => 'nullable|array',
            'upload_ids.*' => 'required|string|uuid',
        ]);

        $ownerKey = 'user:'.$account->id;
        $files = array_values($request->file('files', []) ?? []);
        $uploadIds = array_values($data['upload_ids'] ?? []);

        if ($files === [] && $uploadIds === []) {
            return back()->withInput()->with('error', 'Add at least one file to share.');
        }

        foreach ($uploadIds as $uploadId) {
            try {
                $files[] = $this->chunkedUploads->toUploadedFile($uploadId, $ownerKey);
            } catch (RuntimeException $e) {
                return back()->withInput()->with('error', $e->getMessage());
            }
        }

        try {
            $transfer = $this->transfers->create($account, $data, $files);
        } catch (RuntimeException $e) {
            return back()->withInput()->with('error', $e->getMessage());
        } finally {
            foreach ($uploadIds as $uploadId) {
                $this->chunkedUploads->cleanup($uploadId);
            }
        }

        $success = 'Transfer created. Share the link or QR code with recipients.';
        if ($transfer->recipient_email && $transfer->wantsRecipientMilestone('created') && $transfer->recipientMilestoneSent('created')) {
            $success .= ' A download link was emailed to '.$transfer->recipient_email.'.';
        }

        return redirect()
            ->route('transfer.transfers.show', $transfer)
            ->with('success', $success);
    }

    public function show(Transfer $transfer): View
    {
        $this->authorizeTransfer($transfer);

        $transfer->load(['files', 'qrCode']);
        $previewDataUri = $transfer->qrCode
            ? $this->imageGenerator->previewDataUri($transfer->qrCode)
            : null;

        return view('transfer.transfers.show', [
            'transfer' => $transfer,
            'previewDataUri' => $previewDataUri,
        ]);
    }

    public function destroy(Transfer $transfer): RedirectResponse
    {
        $this->authorizeTransfer($transfer);

        $this->transfers->delete($transfer);

        return redirect()
            ->route('transfer.transfers.index')
            ->with('success', 'Transfer deleted.');
    }

    public function preview(Transfer $transfer): Response
    {
        $this->authorizeTransfer($transfer);
        $qrCode = $transfer->qrCode;
        abort_unless($qrCode, 404);

        $qrCode = $this->imageGenerator->ensureValidImages($qrCode);
        $bytes = $this->imageGenerator->normalizeStoredPng($qrCode->png_path);

        if ($bytes === null) {
            $bytes = $this->imageGenerator->renderPng($qrCode->encodedPayload(), $qrCode->style());
            $this->imageGenerator->generateAndStore($qrCode);
        }

        return response($bytes, 200, [
            'Content-Type' => 'image/png',
            'Cache-Control' => 'private, max-age=3600',
        ]);
    }

    public function download(Transfer $transfer, string $format): StreamedResponse
    {
        $this->authorizeTransfer($transfer);
        $qrCode = $transfer->qrCode;
        abort_unless($qrCode, 404);

        $qrCode = $this->imageGenerator->ensureValidImages($qrCode);
        $filename = Str::slug($qrCode->label).'-qr.'.($format === 'svg' ? 'svg' : 'png');

        if ($format === 'png') {
            $bytes = $this->imageGenerator->normalizeStoredPng($qrCode->png_path);
            if ($bytes === null) {
                $bytes = $this->imageGenerator->renderPng($qrCode->encodedPayload(), $qrCode->style());
                $this->imageGenerator->generateAndStore($qrCode);
            }

            return response()->streamDownload(fn () => print($bytes), $filename, [
                'Content-Type' => 'image/png',
            ]);
        }

        if ($format === 'svg') {
            abort_unless($qrCode->svg_path, 404);

            return response()->streamDownload(
                fn () => print(file_get_contents(storage_path('app/private/qr/'.$qrCode->svg_path))),
                $filename,
                ['Content-Type' => 'image/svg+xml'],
            );
        }

        return $this->pdfExporter->download($qrCode);
    }

    private function authorizeTransfer(Transfer $transfer): void
    {
        abort_unless($transfer->user_id === ladill_account()->id, 403);
    }
}