<?php
declare(strict_types=1);

/** Small cURL wrapper with hard timeouts, used by every provider adapter. */
final class Http
{
    /**
     * @param array<string,string> $headers
     * @return array{status:int, body:string, json:mixed, error:?string}
     */
    public static function request(string $method, string $url, ?string $body = null, array $headers = [], int $timeout = 8): array
    {
        $ch = curl_init($url);
        $hdrs = [];
        foreach ($headers as $k => $v) {
            $hdrs[] = "$k: $v";
        }
        curl_setopt_array($ch, [
            CURLOPT_CUSTOMREQUEST => $method,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_FOLLOWLOCATION => false,
            CURLOPT_CONNECTTIMEOUT => min(5, $timeout),
            CURLOPT_TIMEOUT => $timeout,
            CURLOPT_HTTPHEADER => $hdrs,
            CURLOPT_USERAGENT => 'visit.waterschurch.org/1.0 (+https://visit.waterschurch.org)',
            CURLOPT_SSL_VERIFYPEER => true,
            CURLOPT_SSL_VERIFYHOST => 2,
        ]);
        if ($body !== null) {
            curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
        }
        $out = curl_exec($ch);
        $status = (int)curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
        $err = curl_error($ch) ?: null;
        $text = is_string($out) ? $out : '';
        $json = null;
        if ($text !== '') {
            $decoded = json_decode($text, true);
            $json = json_last_error() === JSON_ERROR_NONE ? $decoded : null;
        }
        return ['status' => $status, 'body' => $text, 'json' => $json, 'error' => $err];
    }

    /**
     * @param array<string,mixed> $payload
     * @param array<string,string> $headers
     * @return array{status:int, body:string, json:mixed, error:?string}
     */
    public static function json(string $method, string $url, ?array $payload, array $headers = [], int $timeout = 8): array
    {
        $headers = ['Content-Type' => 'application/json', 'Accept' => 'application/json'] + $headers;
        return self::request($method, $url, $payload === null ? null : json_encode($payload, JSON_UNESCAPED_SLASHES), $headers, $timeout);
    }

    /** True for statuses/transport errors that are worth retrying later. */
    public static function isTransient(int $status, ?string $error): bool
    {
        return $error !== null || $status === 0 || $status === 408 || $status === 429 || $status >= 500;
    }
}