<?php
declare(strict_types=1);

final class DirectAdminSyncRepository
{
    public function __construct(private string $baseDir = Settings::DATA_DIR)
    {
    }

    /** @param array<int,array<string,mixed>> $entries */
    public function replaceRuleEntries(string $username, string $ruleId, array $entries): void
    {
        $data = $this->read($username);
        $data['rules'][$ruleId] = array_values($entries);
        $this->write($username, $data);
    }

    /** @return array<int,array<string,mixed>> */
    public function entriesForRule(string $username, string $ruleId): array
    {
        $data = $this->read($username);
        return array_values($data['rules'][$ruleId] ?? []);
    }

    /** @return array<string,array<int,array<string,mixed>>> */
    public function allRuleEntries(string $username): array
    {
        return $this->read($username)['rules'];
    }

    /** @return array<int,array<string,mixed>> */
    public function deleteRuleEntries(string $username, string $ruleId): array
    {
        $data = $this->read($username);
        $entries = array_values($data['rules'][$ruleId] ?? []);
        unset($data['rules'][$ruleId]);
        $this->write($username, $data);
        return $entries;
    }

    /** @return array{rules:array<string,array<int,array<string,mixed>>>} */
    private function read(string $username): array
    {
        $path = $this->path($username);
        if (!is_file($path)) {
            return ['rules' => []];
        }
        $data = json_decode((string)file_get_contents($path), true);
        return is_array($data) && isset($data['rules']) && is_array($data['rules']) ? $data : ['rules' => []];
    }

    /** @param array{rules:array<string,array<int,array<string,mixed>>>} $data */
    private function write(string $username, array $data): void
    {
        $path = $this->path($username);
        $dir = dirname($path);
        if (!is_dir($dir)) {
            mkdir($dir, 0700, true);
        }
        $tmp = $path . '.tmp.' . getmypid();
        file_put_contents($tmp, json_encode($data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES), LOCK_EX);
        @chmod($tmp, 0600);
        rename($tmp, $path);
    }

    private function path(string $username): string
    {
        if (!preg_match('/^[A-Za-z0-9._-]+$/', $username)) {
            throw new InvalidArgumentException('Invalid username');
        }
        return rtrim($this->baseDir, '/') . '/users/' . $username . '/da-sync.json';
    }
}