<?php

namespace App\Actions\Document;

use App\Jobs\ProcessUploadedDocumentJob;
use App\Models\Document;
use App\Models\DocumentVersion;
use App\Services\KnowledgeBase\AuditService;
use Illuminate\Http\UploadedFile;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Str;
use RuntimeException;

/**
 * UploadNewVersionAction
 *
 * Upload versi baru untuk dokumen yang sedia ada.
 * Versi lama TIDAK dipadam — kekal dalam storage dan MySQL.
 * Chunk versi lama akan di-deactivate (bukan delete) semasa ingestion.
 */
class UploadNewVersionAction
{
    public function __construct(
        private readonly AuditService $auditService
    ) {}

    public function execute(Document $document, UploadedFile $file, array $data): DocumentVersion
    {
        $fileHash = hash_file('sha256', $file->getRealPath());

        // Semak sama ada hash sama dengan versi semasa
        $currentVersion = $document->currentVersion;
        if ($currentVersion && $currentVersion->file_hash === $fileHash) {
            throw new RuntimeException(
                'Fail ini sama dengan versi semasa. Tiada perubahan.'
            );
        }

        return DB::transaction(function () use ($document, $file, $fileHash, $data) {
            $newVersionNumber = $document->getLatestVersionNumber() + 1;

            // ── Simpan fail baru ──────────────────────────────────────────
            $disk     = config('knowledgebase.upload.storage_disk', 'local');
            $folder   = "documents/{$document->id}/v{$newVersionNumber}";
            $filename = Str::uuid() . '.pdf';
            $path     = $file->storeAs($folder, $filename, $disk);

            if (!$path) {
                throw new RuntimeException('Gagal simpan fail PDF ke storage.');
            }

            // ── Buat rekod versi baru ─────────────────────────────────────
            $version = DocumentVersion::create([
                'document_id'       => $document->id,
                'version_number'    => $newVersionNumber,
                'original_filename' => $file->getClientOriginalName(),
                'stored_path'       => $path,
                'mime_type'         => $file->getMimeType(),
                'file_size'         => $file->getSize(),
                'file_hash'         => $fileHash,
                'processing_status' => DocumentVersion::STATUS_PENDING,
                'is_current'        => false, // akan di-set current semasa ingestion
                'change_notes'      => $data['change_notes'] ?? null,
                'uploaded_by'       => auth()->id(),
            ]);

            // Kemaskini status dokumen ke processing
            $document->update([
                'status'     => Document::STATUS_PROCESSING,
                'updated_by' => auth()->id(),
            ]);

            // ── Audit log ─────────────────────────────────────────────────
            $this->auditService->documentUploaded($document, $version);

            // ── Dispatch job ──────────────────────────────────────────────
            ProcessUploadedDocumentJob::dispatch($version->id);

            return $version;
        });
    }
}