<?php

declare(strict_types=1);

namespace Infrastructure\Persistence;

// @responsibility: CRUD-Operationen für Dokumente im Semantic Explorer

use Domain\Repository\DocumentRepositoryInterface;
use PDO;

final class DocumentRepository implements DocumentRepositoryInterface
{
    private PDO $db;

    public function __construct()
    {
        $this->db = DatabaseFactory::content();
    }

    /**
     * {@inheritDoc}
     */
    public function getStats(): array
    {
        $result = $this->db->query(
            'SELECT
                COUNT(*) as total,
                SUM(CASE WHEN status = "done" THEN 1 ELSE 0 END) as processed,
                SUM(CASE WHEN status = "error" THEN 1 ELSE 0 END) as errors
             FROM documents'
        )->fetch();

        return $result !== false ? $result : ['total' => 0, 'processed' => 0, 'errors' => 0];
    }

    /**
     * {@inheritDoc}
     */
    public function findAll(): array
    {
        return $this->db->query(
            'SELECT d.id, d.filename, d.folder_path, d.mime_type, d.file_size,
                    d.status, d.imported_at, d.processed_at,
                    (SELECT COUNT(*) FROM chunks WHERE document_id = d.id) as chunk_count
             FROM documents d
             ORDER BY d.imported_at DESC'
        )->fetchAll();
    }

    /**
     * {@inheritDoc}
     */
    public function findFiltered(string $status = '', string $search = ''): array
    {
        $sql = 'SELECT d.id, d.filename, d.folder_path, d.source_path, d.mime_type,
                       d.file_size, d.status, d.imported_at, d.processed_at, d.error_message,
                       (SELECT COUNT(*) FROM chunks WHERE document_id = d.id) as chunk_count,
                       (SELECT COALESCE(SUM(token_count), 0) FROM chunks WHERE document_id = d.id) as token_count
                FROM documents d WHERE 1=1';

        $params = [];

        if ($status !== '') {
            $sql .= ' AND d.status = :status';
            $params['status'] = $status;
        }

        if ($search !== '') {
            $sql .= ' AND (d.filename LIKE :search OR d.source_path LIKE :search2)';
            $params['search'] = '%' . $search . '%';
            $params['search2'] = '%' . $search . '%';
        }

        $sql .= ' ORDER BY d.imported_at DESC';

        $stmt = $this->db->prepare($sql);
        $stmt->execute($params);

        return $stmt->fetchAll();
    }

    /**
     * {@inheritDoc}
     */
    public function find(int $id): ?array
    {
        $stmt = $this->db->prepare('SELECT * FROM documents WHERE id = :id');
        $stmt->execute(['id' => $id]);
        $result = $stmt->fetch();

        return $result === false ? null : $result;
    }
}