<?php

namespace App\Config\Validation;

use App\Models\Employee;
use CodeIgniter\HTTP\IncomingRequest;
use Config\OSPOS;
use Config\Services;

/**
 * @property Employee employee
 * @property IncomingRequest request
 */
class OSPOSRules
{
    private IncomingRequest $request;
    private array $config;

    /**
     * Validates the username and password sent to the login view. User is logged in on successful validation.
     *
     * @param string $username Username to check against.
     * @param string $fields Comma separated string of the fields for validation.
     * @param array $data Data sent to the view.
     * @param string|null $error The error sent back to the validation handler on failure.
     * @return bool True if validation passes or false if there are errors.
     * @noinspection PhpUnused
     */
    public function login_check(string $username, string $fields, array $data, ?string &$error = null): bool
    {
        $employee = model(Employee::class);
        $this->request = Services::request();
        $this->config = config(OSPOS::class)->settings;

        // Installation Check
        if (!$this->installation_check()) {
            $error = lang('Login.invalid_installation');

            return false;
        }

        $password = $data['password'];
        if (!$employee->login($username, $password)) {
            $error = lang('Login.invalid_username_and_password');

            return false;
        }

        $gcaptcha_enabled = array_key_exists('gcaptcha_enable', $this->config) && $this->config['gcaptcha_enable'];
        if ($gcaptcha_enabled) {
            $g_recaptcha_response = $this->request->getPost('g-recaptcha-response');

            if (!$this->gcaptcha_check($g_recaptcha_response)) {
                $error = lang('Login.invalid_gcaptcha');

                return false;
            }
        }

        return true;
    }

    /**
     * Checks to see if GCaptcha verification was successful.
     *
     * @param $response
     * @return bool true on successful GCaptcha verification or false if GCaptcha failed.
     */
    private function gcaptcha_check($response): bool
    {
        if (!empty($response)) {
            $check = [
                'secret'   => $this->config['gcaptcha_secret_key'],
                'response' => $response,
                'remoteip' => $this->request->getIPAddress()
            ];

            $ch = curl_init();

            curl_setopt($ch, CURLOPT_URL, "https://www.google.com/recaptcha/api/siteverify");
            curl_setopt($ch, CURLOPT_POST, true);
            curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($check));
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

            $result = curl_exec($ch);

            curl_close($ch);

            $status = json_decode($result, true);

            if (!empty($status['success'])) {
                return true;
            }
        }

        return false;
    }

    /**
     * Checks to make sure dependency PHP extensions are installed
     *
     * @return bool
     */
    private function installation_check(): bool
    {
        $installed_extensions = implode(', ', get_loaded_extensions());
        $required_extensions = ['bcmath', 'intl', 'gd', 'openssl', 'mbstring', 'curl', 'xml', 'json'];
        $pattern = '/';

        foreach ($required_extensions as $extension) {
            $pattern .= '(?=.*\b' . preg_quote($extension, '/') . '\b)';
        }

        $pattern .= '/i';
        $is_installed = preg_match($pattern, $installed_extensions);

        if (!$is_installed) {
            log_message('error', '[ERROR] Check your php.ini.');
            log_message('error', "PHP installed extensions: $installed_extensions");
            log_message('error', 'PHP required extensions: ' . implode(', ', $required_extensions));
        }

        return $is_installed;
    }

    /**
     * Validates the candidate as a decimal number. Takes the locale into account. Used in validation rule calls.
     *
     * @param string $candidate
     * @param string|null $error
     * @return bool
     * @noinspection PhpUnused
     */
    public function decimal_locale(string $candidate, ?string &$error = null): bool
    {
        return parse_decimals($candidate) !== false;
    }
}