<?php

namespace App\Services\Admin\Notice;

use App\Models\GcBoard;
use App\Repositories\Admin\Notice\AdminNoticeRepository;
use Illuminate\Http\UploadedFile;
use Illuminate\Support\Facades\Storage;

final class AdminNoticeService
{
    private const GUBUN = 'notice';
    private const DISK  = 'public';
    private const DIR   = 'bbs';

    public function __construct(
        private readonly AdminNoticeRepository $repo,
    ) {}

    public function paginate(array $filters, int $perPage = 15)
    {
        // paginator 링크 쿼리스트링 유지
        return $this->repo->paginate($filters, $perPage)->withQueryString();
    }

    public function get(int $id): GcBoard
    {
        return $this->repo->findOrFailForEdit($id);
    }

    public function create(array $data, ?UploadedFile $file1, ?UploadedFile $file2, int $adminId): int
    {
        // 파일은 먼저 저장(성공 시 DB 반영), 예외 시 롤백+파일 삭제
        $new1 = $file1 ? $this->storeFile($file1) : null;
        $new2 = $file2 ? $this->storeFile($file2) : null;

        try {
            return $this->repo->transaction(function () use ($data, $adminId, $new1, $new2) {

                $wantPinned = !empty($data['first_sign']);
                $firstSign  = 0;

                if ($wantPinned) {
                    $max = $this->repo->maxFirstSignForUpdate(); // lock 포함
                    $firstSign = $max + 1; // ✅ 상단공지 순번(큰 값이 먼저)
                }

                $payload = [
                    'gubun'      => self::GUBUN,
                    'subject'    => (string)($data['subject'] ?? ''),
                    'content'    => (string)($data['content'] ?? ''),
                    'admin_num'  => $adminId,
                    'regdate'    => now()->format('Y-m-d H:i:s'),
                    'hiding'     => 'N', // 기본 노출
                    'first_sign' => $firstSign,
                    'link_01'    => $this->nullIfBlank($data['link_01'] ?? null),
                    'link_02'    => $this->nullIfBlank($data['link_02'] ?? null),
                    'hit'        => 0,
                ];

                if ($new1) $payload['file_01'] = $new1;
                if ($new2) $payload['file_02'] = $new2;

                $row = $this->repo->create($payload);
                return (int) $row->getKey();
            });
        } catch (\Throwable $e) {
            // DB 실패 시 새로 저장한 파일 제거
            $this->deletePhysicalFiles([$new1, $new2]);
            throw $e;
        }
    }

    public function update(int $id, array $data, ?UploadedFile $file1, ?UploadedFile $file2): void
    {
        // 새 파일 먼저 저장
        $new1 = $file1 ? $this->storeFile($file1) : null;
        $new2 = $file2 ? $this->storeFile($file2) : null;

        $oldToDelete = [];

        try {
            $oldToDelete = (array) $this->repo->transaction(function () use ($id, $data, $new1, $new2) {

                $row = $this->repo->lockForUpdate($id);

                $hiding = !empty($data['hiding']) ? 'Y' : 'N';

                // ✅ first_sign(상단공지) 정리된 로직
                // - 체크 해제: 0
                // - 체크 + 기존이 0: max+1 부여
                // - 체크 + 기존이 >0: 기존 값 유지
                $wantPinned = !empty($data['first_sign']);
                $firstSign  = (int)($row->first_sign ?? 0);

                if ($wantPinned) {
                    if ($firstSign <= 0) {
                        $firstSign = $this->repo->maxFirstSignForUpdate() + 1;
                    }
                } else {
                    $firstSign = 0;
                }

                $payload = [
                    'subject'    => (string)($data['subject'] ?? ''),
                    'content'    => (string)($data['content'] ?? ''),
                    'link_01'    => $this->nullIfBlank($data['link_01'] ?? null),
                    'link_02'    => $this->nullIfBlank($data['link_02'] ?? null),
                    'hiding'     => $hiding,
                    'first_sign' => $firstSign,
                ];

                $oldFiles = [];

                if ($new1) {
                    $oldFiles[] = (string)($row->file_01 ?? '');
                    $payload['file_01'] = $new1;
                }

                if ($new2) {
                    $oldFiles[] = (string)($row->file_02 ?? '');
                    $payload['file_02'] = $new2;
                }

                $this->repo->update($row, $payload);

                // 트랜잭션 밖에서 삭제할 이전 파일명 반환
                return $oldFiles;
            });
        } catch (\Throwable $e) {
            // DB 실패 시 새로 저장한 파일 제거
            $this->deletePhysicalFiles([$new1, $new2]);
            throw $e;
        }

        // ✅ 커밋 이후에만 기존 파일 삭제
        $this->deletePhysicalFiles($oldToDelete);
    }

    public function delete(int $id): void
    {
        $files = (array) $this->repo->transaction(function () use ($id) {
            $row = $this->repo->lockForUpdate($id);

            $files = [
                (string)($row->file_01 ?? ''),
                (string)($row->file_02 ?? ''),
            ];

            $this->repo->delete($row);
            return $files;
        });

        $this->deletePhysicalFiles($files);
    }

    public function download(int $id, int $slot): array
    {
        $row = $this->repo->findOrFailForEdit($id);

        $file = $slot === 1
            ? (string)($row->file_01 ?? '')
            : (string)($row->file_02 ?? '');

        $file = trim($file);
        if ($file === '') return ['ok' => false, 'path' => '', 'name' => ''];

        $path = self::DIR.'/'.basename($file);
        if (!Storage::disk(self::DISK)->exists($path)) {
            return ['ok' => false, 'path' => '', 'name' => ''];
        }

        return ['ok' => true, 'path' => $path, 'name' => $file];
    }

    private function storeFile(UploadedFile $file): string
    {
        $orig = $file->getClientOriginalName();
        $safe = $this->safeFilename($orig);

        $base = pathinfo($safe, PATHINFO_FILENAME);
        $ext  = pathinfo($safe, PATHINFO_EXTENSION);
        $name = $safe;

        // 충돌 방지
        $i = 0;
        while (Storage::disk(self::DISK)->exists(self::DIR.'/'.$name)) {
            $i++;
            $suffix = date('YmdHis').'_'.mt_rand(1000, 9999).'_'.$i;
            $name = $base.'_'.$suffix.($ext ? '.'.$ext : '');
        }

        Storage::disk(self::DISK)->putFileAs(self::DIR, $file, $name);
        return $name;
    }

    private function deletePhysicalFiles(array $files): void
    {
        foreach ($files as $f) {
            $f = trim((string)$f);
            if ($f === '') continue;

            $path = self::DIR.'/'.$f;
            if (Storage::disk(self::DISK)->exists($path)) {
                Storage::disk(self::DISK)->delete($path);
            }
        }
    }

    private function safeFilename(string $name): string
    {
        $name = trim($name);
        $name = preg_replace('/[^\pL\pN\.\-\_\s]/u', '', $name) ?: 'file';
        $name = preg_replace('/\s+/', '_', $name);
        $name = preg_replace('/_+/', '_', $name);
        return mb_substr($name, 0, 180);
    }

    private function nullIfBlank($v): ?string
    {
        $v = trim((string)($v ?? ''));
        return $v === '' ? null : $v;
    }
}