<?php

function json_success(mixed $data, int $status = 200): never {
    http_response_code($status);
    header('Content-Type: application/json; charset=UTF-8');
    echo json_encode(["ok" => true, "data" => $data]);
    exit;
}

function json_error(string $code, string $message, int $status = 400): never {
    http_response_code($status);
    header('Content-Type: application/json; charset=UTF-8');
    echo json_encode(["ok" => false, "error" => ["code" => $code, "message" => $message]]);
    exit;
}

function read_json_body(): array {
    $raw = file_get_contents('php://input');
    $data = json_decode($raw, true);
    if (!is_array($data)) {
        json_error('INVALID_BODY', 'Request body must be valid JSON', 400);
    }
    return $data;
}