<?php

namespace App\Http\Controllers\Transfer;

use App\Http\Controllers\Controller;
use App\Models\Transfer;
use App\Models\TransferFile;
use App\Models\User;
use App\Services\Transfer\FileStorageService;
use App\Services\Transfer\TransferRecipientMailService;
use App\Services\Transfer\TransferService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Storage;
use Illuminate\View\View;
use RuntimeException;
use Symfony\Component\HttpFoundation\StreamedResponse;
use ZipArchive;

class FilesController extends Controller
{
    public function __construct(
        private TransferService $transfers,
        private FileStorageService $storage,
    ) {}

    public function index(Request $request): View
    {
        $account = ladill_account();
        $search = trim((string) $request->query('q', ''));
        $folderId = $request->integer('folder') ?: null;
        $sort = (string) $request->query('sort', 'newest');
        $viewMode = (string) $request->query('view', $folderId ? 'files' : 'all');

        $folderTransfer = null;
        if ($folderId) {
            $folderTransfer = Transfer::query()
                ->where('user_id', $account->id)
                ->where('is_folder', true)
                ->where('status', '!=', Transfer::STATUS_DELETED)
                ->findOrFail($folderId);
        }

        $filesQuery = TransferFile::query()
            ->whereHas('transfer', fn ($q) => $q
                ->where('user_id', $account->id)
                ->where('status', '!=', Transfer::STATUS_DELETED)
                ->when($folderTransfer, fn ($inner) => $inner->whereKey($folderTransfer->id),
                    fn ($inner) => $inner->where('is_folder', false)))
            ->when($search !== '', fn ($q) => $q->where('original_name', 'like', '%'.$search.'%'))
            ->with(['transfer.qrCode'])
            ->when($sort === 'oldest', fn ($q) => $q->oldest())
            ->when($sort === 'name', fn ($q) => $q->orderBy('original_name'))
            ->when($sort === 'size', fn ($q) => $q->orderByDesc('size_bytes'))
            ->when($sort === 'downloads', fn ($q) => $q->orderByDesc('downloads_total'))
            ->when($sort === 'newest', fn ($q) => $q->latest());

        $files = $filesQuery->paginate(30)->withQueryString();

        $folders = Transfer::query()
            ->where('user_id', $account->id)
            ->where('is_folder', true)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->withCount('files')
            ->when($search !== '', fn ($q) => $q->where('title', 'like', '%'.$search.'%'))
            ->orderBy('title')
            ->get();

        $moveTargets = Transfer::query()
            ->where('user_id', $account->id)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->where(function ($query) {
                $query->where('is_folder', true)->orWhere('is_root_storage', true);
            })
            ->orderBy('title')
            ->get(['id', 'title', 'is_root_storage']);

        $storageBytes = Transfer::query()
            ->where('user_id', $account->id)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->sum('storage_bytes');

        return view('transfer.files.index', [
            'files' => $files,
            'folders' => $folders,
            'folderTransfer' => $folderTransfer,
            'moveTargets' => $moveTargets,
            'search' => $search,
            'sort' => $sort,
            'viewMode' => $viewMode,
            'storageBytes' => (int) $storageBytes,
            'storageGb' => round($storageBytes / (1024 * 1024 * 1024), 2),
            'pricePerGb' => (float) config('transfer.price_per_gb_month', 0.30),
        ]);
    }

    public function download(TransferFile $file): StreamedResponse
    {
        $this->authorizeFile($file);
        abort_unless($file->existsOnDisk(), 404);

        return Storage::disk($file->disk)->response(
            $file->path,
            $file->original_name,
            ['Content-Type' => $file->mime_type],
        );
    }

    public function bulkDownload(Request $request): StreamedResponse|RedirectResponse
    {
        $files = $this->authorizedFiles($request->input('files', []));

        if ($files->isEmpty()) {
            return back()->with('error', 'Select at least one file to download.');
        }

        if ($files->count() === 1) {
            $file = $files->first();
            abort_unless($file->existsOnDisk(), 404);

            return Storage::disk($file->disk)->response(
                $file->path,
                $file->original_name,
                ['Content-Type' => $file->mime_type],
            );
        }

        $filename = 'ladill-files-'.now()->format('Y-m-d-His').'.zip';

        return response()->streamDownload(function () use ($files) {
            $zip = new ZipArchive;
            $tmp = tempnam(sys_get_temp_dir(), 'ladill_zip_');
            if ($tmp === false || $zip->open($tmp, ZipArchive::CREATE | ZipArchive::OVERWRITE) !== true) {
                throw new RuntimeException('Could not prepare download archive.');
            }

            $usedNames = [];
            foreach ($files as $file) {
                if (! $file->existsOnDisk()) {
                    continue;
                }

                $name = $file->original_name;
                if (isset($usedNames[$name])) {
                    $usedNames[$name]++;
                    $ext = pathinfo($name, PATHINFO_EXTENSION);
                    $base = pathinfo($name, PATHINFO_FILENAME);
                    $name = $base.' ('.$usedNames[$name].')'.($ext !== '' ? '.'.$ext : '');
                } else {
                    $usedNames[$name] = 0;
                }

                $zip->addFromString($name, Storage::disk($file->disk)->get($file->path));
            }

            $zip->close();
            readfile($tmp);
            @unlink($tmp);
        }, $filename, ['Content-Type' => 'application/zip']);
    }

    public function destroy(TransferFile $file): RedirectResponse
    {
        $this->authorizeFile($file);
        $this->transfers->deleteFile($file);

        return back()->with('success', 'File deleted.');
    }

    public function bulkDestroy(Request $request): RedirectResponse
    {
        $files = $this->authorizedFiles($request->input('files', []));

        if ($files->isEmpty()) {
            return back()->with('error', 'Select at least one file to delete.');
        }

        $this->transfers->deleteFiles($files->all());

        return back()->with('success', $files->count().' file'.($files->count() === 1 ? '' : 's').' deleted.');
    }

    public function move(Request $request): RedirectResponse
    {
        $data = $request->validate([
            'destination' => 'required|integer|exists:transfers,id',
            'files' => 'required|array|min:1',
            'files.*' => 'integer|exists:transfer_files,id',
        ]);

        $destination = Transfer::query()
            ->where('user_id', ladill_account()->id)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->where(function ($query) {
                $query->where('is_folder', true)->orWhere('is_root_storage', true);
            })
            ->findOrFail($data['destination']);

        $files = $this->authorizedFiles($data['files']);
        $this->transfers->moveFiles($destination, $files->all());

        return redirect()
            ->route('transfer.files.index', $destination->is_folder ? ['folder' => $destination->id] : [])
            ->with('success', $files->count().' file'.($files->count() === 1 ? '' : 's').' moved to '.$destination->title.'.');
    }

    public function share(Request $request): JsonResponse
    {
        $files = $this->authorizedFiles($request->input('files', []));

        if ($files->isEmpty()) {
            return response()->json(['message' => 'Select at least one file to share.'], 422);
        }

        $links = $files
            ->map(fn (TransferFile $file) => $file->transfer->qrCode?->publicUrl())
            ->filter()
            ->unique()
            ->values()
            ->all();

        return response()->json([
            'links' => $links,
            'message' => count($links).' share link'.(count($links) === 1 ? '' : 's').' ready to copy.',
        ]);
    }

    public function reshareEmail(Request $request): RedirectResponse
    {
        $data = $request->validate([
            'transfer' => 'required|integer|exists:transfers,id',
            'email' => 'required|email|max:255',
        ]);

        $transfer = Transfer::query()
            ->where('user_id', ladill_account()->id)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->findOrFail($data['transfer']);

        $transfer->forceFill([
            'recipient_email' => $data['email'],
            'recipient_email_milestones' => ['created'],
            'recipient_milestones_sent' => [],
        ])->save();

        app(TransferRecipientMailService::class)->notifyRecipient($transfer->fresh(['files', 'qrCode', 'user']), 'created');

        return back()->with('success', 'Share link emailed to '.$data['email'].'.');
    }

    public function openInEmail(Request $request): RedirectResponse
    {
        $files = $this->authorizedFiles($request->input('files', []));

        if ($files->isEmpty()) {
            return back()->with('error', 'Select at least one file to open in email.');
        }

        $links = $files
            ->map(fn (TransferFile $file) => $file->transfer->qrCode?->publicUrl())
            ->filter()
            ->unique()
            ->values();

        $names = $files->pluck('original_name')->unique()->take(3)->implode(', ');
        if ($files->count() > 3) {
            $names .= ' +'.($files->count() - 3).' more';
        }

        $body = "Hi,\n\nI'm sharing the following files with you via Ladill Transfer:\n\n";
        foreach ($links as $link) {
            $body .= $link."\n";
        }
        $body .= "\nDownload using the link".($links->count() === 1 ? '' : 's')." above.";

        $url = ladill_webmail_url('').'?'.http_build_query([
            'compose' => 1,
            'subject' => 'Shared files: '.$names,
            'body' => $body,
        ]);

        return redirect()->away($url);
    }

    public function storeFolder(Request $request): RedirectResponse
    {
        $data = $request->validate([
            'name' => 'required|string|max:120',
            'folder' => 'nullable|integer|exists:transfers,id',
        ]);

        $account = ladill_account();
        $parent = null;
        if (! empty($data['folder'])) {
            $parent = Transfer::query()
                ->where('user_id', $account->id)
                ->where('is_folder', true)
                ->findOrFail($data['folder']);
        }

        try {
            $folder = $this->storage->createFolder($account, $data['name'], $parent);
        } catch (RuntimeException $e) {
            return back()->with('error', $e->getMessage());
        }

        return redirect()
            ->route('transfer.files.index', ['folder' => $folder->id])
            ->with('success', 'Folder created.');
    }

    public function checkUpload(Request $request): JsonResponse
    {
        $data = $request->validate([
            'filenames' => 'required|array|min:1',
            'filenames.*' => 'required|string|max:255',
            'folder' => 'nullable|integer|exists:transfers,id',
        ]);

        $account = ladill_account();
        $folder = $this->resolveUploadFolder($account, $data['folder'] ?? null);

        $conflicts = $this->storage->findConflicts(
            $account,
            $folder,
            $data['filenames'],
        );

        return response()->json(['conflicts' => $conflicts]);
    }

    public function storeUpload(Request $request): RedirectResponse|JsonResponse
    {
        $data = $request->validate([
            'files' => 'required|array|min:1',
            'files.*' => 'required|file',
            'folder' => 'nullable|integer|exists:transfers,id',
            'resolutions' => 'nullable|array',
            'resolutions.*' => 'in:replace,keep_both',
        ]);

        $account = ladill_account();
        $folder = $this->resolveUploadFolder($account, $data['folder'] ?? null);
        $files = array_values($request->file('files', []) ?? []);

        try {
            $uploaded = $this->storage->uploadFiles(
                $account,
                $folder,
                $files,
                $data['resolutions'] ?? [],
            );
        } catch (RuntimeException $e) {
            if ($request->expectsJson()) {
                return response()->json(['message' => $e->getMessage()], 422);
            }

            return back()->with('error', $e->getMessage());
        }

        $count = count($uploaded);
        $message = $count.' file'.($count === 1 ? '' : 's').' uploaded.';

        if ($request->expectsJson()) {
            return response()->json(['message' => $message, 'count' => $count]);
        }

        return back()->with('success', $message);
    }

    private function resolveUploadFolder(User $user, ?int $folderId): ?Transfer
    {
        if ($folderId === null) {
            return null;
        }

        return Transfer::query()
            ->where('user_id', $user->id)
            ->where('is_folder', true)
            ->where('status', '!=', Transfer::STATUS_DELETED)
            ->findOrFail($folderId);
    }

    /** @param  array<int|string>|null  $ids */
    private function authorizedFiles(?array $ids): Collection
    {
        $ids = collect($ids ?? [])
            ->filter(fn ($id) => is_numeric($id))
            ->map(fn ($id) => (int) $id)
            ->unique()
            ->values()
            ->all();

        if ($ids === []) {
            return collect();
        }

        return TransferFile::query()
            ->whereIn('id', $ids)
            ->whereHas('transfer', fn ($q) => $q
                ->where('user_id', ladill_account()->id)
                ->where('status', '!=', Transfer::STATUS_DELETED))
            ->with(['transfer.qrCode'])
            ->get();
    }

    private function authorizeFile(TransferFile $file): void
    {
        abort_unless(
            $file->transfer()->where('user_id', ladill_account()->id)->exists(),
            403,
        );
    }
}