<?php

declare(strict_types=1);

namespace MeshVault\Repository;

use DomainException;
use InvalidArgumentException;
use PDO;

final class PdoCatalogRepository extends PdoRepository implements CatalogRepositoryInterface
{
    public function ensureModel(string $folderPath, string $modelName): int
    {
        if ($modelName === '') {
            throw new InvalidArgumentException('Model name must not be empty.');
        }
        return $this->transaction(function () use ($folderPath, $modelName): int {
            $folder = $this->ensureFolder($folderPath);
            $this->execute(
                'INSERT INTO models (folder_id, name) VALUES (?, ?) ON CONFLICT (folder_id, name) DO NOTHING',
                [$folder, $modelName]
            );
            return (int) $this->row(
                'SELECT id FROM models WHERE folder_id = ? AND name = ?',
                [$folder, $modelName]
            )['id'];
        });
    }

    public function recordFile(
        int $modelId,
        string $managedPath,
        string $hash,
        int $size,
        ?string $mime = null,
        string $status = 'Present'
    ): int {
        $this->validateStatus($status);
        if ($managedPath === '' || $hash === '' || $size < 0) {
            throw new InvalidArgumentException('A file requires a path, hash and non-negative size.');
        }
        return $this->transaction(function () use ($modelId, $managedPath, $hash, $size, $mime, $status): int {
            // Serialize catalog writers on the root row, including paths assigned to different models.
            $this->ensureFolder('/');
            $this->execute("UPDATE folders SET name = name WHERE path = '/'");
            $existing = $this->row('SELECT * FROM files WHERE managed_path = ?', [$managedPath]);
            if ($existing !== null) {
                if (
                    (int) $existing['model_id'] !== $modelId || $existing['hash'] !== $hash
                    || (int) $existing['size'] !== $size
                ) {
                    throw new DomainException('Managed path already records a different file.');
                }
                return (int) $existing['id'];
            }
            $folder = $this->ensureFolder(dirname(str_replace('\\', '/', $managedPath)));
            $file = $this->row(
                'INSERT INTO files (model_id, folder_id, name, managed_path, hash, size, mime_type, status)'
                . ' VALUES (?, ?, ?, ?, ?, ?, ?, ?) RETURNING id',
                [$modelId, $folder, basename($managedPath), $managedPath, $hash, $size, $mime, $status]
            );
            return (int) $file['id'];
        });
    }

    public function aggregate(int $modelId): ?array
    {
        return $this->transaction(function () use ($modelId): ?array {
            $model = $this->row('SELECT * FROM models WHERE id = ?', [$modelId]);
            if ($model === null) {
                return null;
            }
            return [
                'model' => $model,
                'folder' => $this->row('SELECT * FROM folders WHERE id = ?', [$model['folder_id']]),
                'files' => $this->execute('SELECT * FROM files WHERE model_id = ? ORDER BY id', [$modelId])
                    ->fetchAll(PDO::FETCH_ASSOC),
            ];
        });
    }

    public function setFileStatus(int $fileId, string $status): void
    {
        $this->validateStatus($status);
        if (
            $this->execute(
                'UPDATE files SET status = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?',
                [$status, $fileId]
            )->rowCount() === 0
        ) {
            throw new DomainException('Unknown file.');
        }
    }

    private function validateStatus(string $status): void
    {
        if (!in_array($status, ['Present', 'Missing', 'Updated', 'Duplicate'], true)) {
            throw new InvalidArgumentException('Invalid file status.');
        }
    }

    private function ensureFolder(string $path): int
    {
        $segments = array_values(array_filter(explode('/', str_replace('\\', '/', $path)), 'strlen'));
        $segments = array_values(array_filter($segments, static fn (string $part): bool => $part !== '.'));
        if (in_array('..', $segments, true)) {
            throw new InvalidArgumentException('Folder traversal is not allowed.');
        }
        $parent = null;
        $current = '';
        foreach (array_merge([''], $segments) as $segment) {
            $current = $segment === '' ? '/' : rtrim($current, '/') . '/' . $segment;
            $this->execute(
                'INSERT INTO folders (parent_id, name, path) VALUES (?, ?, ?) ON CONFLICT (path) DO NOTHING',
                [$parent, $segment === '' ? '/' : $segment, $current]
            );
            $parent = (int) $this->row('SELECT id FROM folders WHERE path = ?', [$current])['id'];
        }
        return $parent;
    }
}