<?php
// This file is part of Moodle - http://moodle.org/

/**
 * HTTP client for MeetLet registration API.
 *
 * @package    mod_meetletacbfree
 * @copyright  2026 MeetLet
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

namespace mod_meetletacbfree\registration;

defined('MOODLE_INTERNAL') || die();

/**
 * Talks to MeetLet /api/v1 licensing endpoints (free-tier registration).
 */
class api_client {
    /** @var string */
    protected $baseurl;

    public function __construct(?string $baseurl = null) {
        $url = $baseurl ?? manager::api_base_url();
        $this->baseurl = rtrim(trim($url), '/');
    }

    public function activate(array $body): array {
        return $this->request('/api/v1/activations', $body);
    }

    public function validate(array $body): array {
        return $this->request('/api/v1/validations', $body);
    }

    public function refresh(array $body): array {
        return $this->request('/api/v1/authorizations/refresh', $body);
    }

    public function deactivate(string $installationid, array $body): array {
        $path = '/api/v1/activations/' . rawurlencode($installationid) . '/deactivate';
        return $this->request($path, $body);
    }

    /**
     * @return array data from API envelope
     */
    protected function request(string $path, array $body): array {
        global $CFG;
        require_once($CFG->libdir . '/filelib.php');

        $url = $this->baseurl . $path;
        $json = json_encode($body, JSON_UNESCAPED_SLASHES);
        if ($json === false) {
            throw new registration_exception(error_mapper::LOCAL_NETWORK_ERROR, 'Could not encode request JSON');
        }

        $curl = new \curl(['ignoresecurity' => true]);
        $raw = $curl->post($url, $json, [
            'CURLOPT_HTTPHEADER' => [
                'Content-Type: application/json',
                'Accept: application/json',
            ],
            'CURLOPT_TIMEOUT' => 30,
        ]);

        $info = $curl->get_info();
        $httpcode = (int)($info['http_code'] ?? 0);

        if ($curl->get_errno()) {
            throw new registration_exception(
                error_mapper::LOCAL_NETWORK_ERROR,
                $curl->error . ' (url=' . $url . ')'
            );
        }

        $raw = is_string($raw) ? trim($raw) : '';
        if ($raw === '') {
            throw new registration_exception(
                error_mapper::LOCAL_NETWORK_ERROR,
                'Empty response HTTP ' . $httpcode . ' from ' . $url
            );
        }

        $decoded = json_decode($raw, true);
        if (!is_array($decoded)) {
            $snippet = \core_text::substr(preg_replace('/\s+/', ' ', $raw), 0, 180);
            throw new registration_exception(
                error_mapper::LOCAL_NETWORK_ERROR,
                'Invalid JSON (HTTP ' . $httpcode . '): ' . $snippet
            );
        }

        $requestid = isset($decoded['request_id']) ? (string)$decoded['request_id'] : null;

        if (empty($decoded['success'])) {
            $err = is_array($decoded['error'] ?? null) ? $decoded['error'] : [];
            $code = (string)($err['code'] ?? 'UNKNOWN');
            $message = (string)($err['message'] ?? 'Registration request failed');
            $details = isset($err['details']) && is_array($err['details']) ? $err['details'] : null;
            throw new registration_exception($code, $message, $details, $requestid);
        }

        $data = $decoded['data'] ?? [];
        if (!is_array($data)) {
            $data = [];
        }
        if ($requestid !== null && $requestid !== '') {
            $data['_request_id'] = $requestid;
        }
        return $data;
    }
}