<?php

declare(strict_types=1);

namespace App\Ingest;

use App\Index\IndexMetaManager;
use App\Knowledge\ChunkManager;
use App\Vector\VectorIndexBuilder;

final readonly class VectorRebuildService
{
    public function __construct(
        private VectorIndexBuilder $vectorBuilder,
        private IndexMetaManager   $metaManager,
        private ChunkManager       $chunkManager,
    ) {}

    /**
     * Führt einen vollständigen, deterministischen FAISS-Rebuild aus.
     *
     * Ablauf:
     * 1. Rebuild des Vector Index aus index.ndjson
     * 2. Chunk-Zählung via ChunkManager
     * 3. Runtime-Stats atomar aktualisieren
     */
    public function rebuild(?string $logPath = null): void
    {
        // ✅ Stelle sicher, dass index_meta.json existiert
        $this->metaManager->ensureExists();

        // 1️⃣ Vector Index neu bauen
        $this->vectorBuilder->rebuildFromNdjson($logPath);

        // 2️⃣ Chunk Count streaming-safe zählen
        $chunkCount = $this->chunkManager->countAllChunks();

        // 3️⃣ Runtime-Stats aktualisieren (atomar)
        $this->metaManager->updateRuntimeStats($chunkCount);
    }
}