<?php

// SPDX-FileCopyrightText: 2026 Icinga GmbH <https://icinga.com>
// SPDX-License-Identifier: GPL-3.0-or-later

namespace Icinga\Forms\Account;

use Icinga\Application\ClassLoader;
use Icinga\Application\Hook\TwoFactorHook;
use Icinga\Application\Logger;
use Icinga\Authentication\Auth;
use Icinga\Exception\IcingaException;
use Icinga\Web\RememberMe;
use Icinga\Web\Session;
use ipl\Html\Attributes;
use ipl\Html\FormElement\FieldsetElement;
use ipl\Web\Common\CsrfCounterMeasure;
use ipl\Web\Common\FormUid;
use ipl\Web\Compat\CompatForm;
use ipl\Web\Url;
use LogicException;
use Throwable;

/**
 * Form for enrolling in and unenrolling from a two-factor authentication method
 */
class TwoFactorEnrollmentForm extends CompatForm
{
    use CsrfCounterMeasure;
    use FormUid;

    /** @var string Form field name for the selected 2FA method */
    public const METHOD = 'twofactor_method';

    /** @var string The submit button to enroll into a 2FA method */
    protected const SUBMIT_ENROLL = 'submit_twofactor_enroll';

    /** @var string The submit button to unenroll from a 2FA method */
    protected const SUBMIT_UNENROLL = 'submit_twofactor_unenroll';

    /** @var bool Whether the user is already enrolled in a 2FA method */
    protected bool $enrolled = false;

    /**
     * Create a new TwoFactorEnrollmentForm
     */
    public function __construct()
    {
        $this->setAttribute('name', 'form_twofactor_enrollment');
    }

    /**
     * Set whether the user is already enrolled in a 2FA method
     *
     * Must be called before the form is assembled.
     *
     * @param bool $enrolled Whether the user is enrolled
     *
     * @return $this
     *
     * @throws LogicException If called after the form has been assembled
     */
    public function setEnrolled(bool $enrolled): static
    {
        if ($this->hasBeenAssembled) {
            throw new LogicException('setEnrolled() must be called before the form is assembled');
        }

        $this->enrolled = $enrolled;

        return $this;
    }

    protected function assemble(): void
    {
        $this->addCsrfCounterMeasure(Session::getSession()->getId());
        $this->addElement($this->createUidElement());

        $this->addElement('select', static::METHOD, [
            'label'           => $this->translate('2FA Method'),
            'class'           => 'autosubmit',
            'disabled'        => $this->enrolled,
            'disabledOptions' => [''],
            'options'         => array_merge(
                ['' => sprintf(' - %s - ', $this->translate('Please choose'))],
                iterator_to_array(TwoFactorHook::yieldMethods())
            ),
            'required'        => true
        ]);

        if ($this->enrolled) {
            $this->addElement('submit', static::SUBMIT_UNENROLL, [
                'label'               => $this->translate('Unenroll'),
                'data-progress-label' => $this->translate('Unenrolling')
            ]);

            return;
        }

        $method = $this->getPopulatedValue(static::METHOD);

        if ($method === null) {
            return;
        }

        $twoFactor = TwoFactorHook::fromName($method);

        $configFieldset = new FieldsetElement($twoFactor->getName());
        $this->addElement($configFieldset);
        try {
            $twoFactor->assembleEnrollmentFormElements($configFieldset);
        } catch (Throwable $e) {
            Logger::error("%s\n%s", $e->getMessage(), IcingaException::getConfidentialTraceAsString($e));
            $this->addMessage(
                $this->translate('Two-factor method "%s" failed to assemble enrollment form elements: %s'),
                $twoFactor->getName(),
                $e->getMessage()
            );
            $this->onError();

            return;
        }

        if ($configFieldset->getName() !== $twoFactor->getName()) {
            throw new LogicException(sprintf(
                '%s::assembleEnrollmentFormElements() must not rename the fieldset. The name "%s" is used'
                . 'as the element key in onSuccess() to retrieve the fieldset, but it was changed to "%s".',
                get_class($twoFactor),
                $twoFactor->getName(),
                $configFieldset->getName()
            ));
        }
        $configFieldset->addAttributes(Attributes::create([
            'class' => 'icinga-module module-' . ClassLoader::extractModuleName(get_class($twoFactor))
        ]));

        $this->addElement('submit', static::SUBMIT_ENROLL, [
            'label'               => $this->translate('Enroll'),
            'data-progress-label' => $this->translate('Enrolling')
        ]);
    }

    protected function onSuccess(): void
    {
        $twoFactor = TwoFactorHook::fromName($this->getValue(static::METHOD));

        switch ($this->getPressedSubmitElement()?->getName()) {
            case static::SUBMIT_ENROLL:
                /** @var FieldsetElement $configFieldset */
                $configFieldset = $this->getElement($twoFactor->getName());
                try {
                    if (! $twoFactor->enroll($configFieldset)) {
                        $this->onError();

                        // Don't redirect in this case, as the user might want to try again.
                        return;
                    }
                } catch (Throwable $e) {
                    Logger::error("%s\n%s", $e->getMessage(), IcingaException::getConfidentialTraceAsString($e));
                    $this->addMessage(
                        $this->translate('Could not enroll in two-factor method: %s'),
                        $e->getMessage()
                    );
                    $this->onError();

                    return;
                }

                break;
            case static::SUBMIT_UNENROLL:
                try {
                    $twoFactor->unenroll();
                } catch (Throwable $e) {
                    Logger::error("%s\n%s", $e->getMessage(), IcingaException::getConfidentialTraceAsString($e));
                    $this->addMessage(
                        $this->translate('Could not unenroll from two-factor method: %s'),
                        $e->getMessage()
                    );
                    $this->onError();

                    return;
                }

                break;
            default:
                return;
        }

        // Revoke all remember-me cookies for the current user. On enrollment,
        // existing cookies would bypass the new 2FA requirement. On unenrollment,
        // cookies issued during the enrolled period were only granted after a
        // successful 2FA challenge and should not remain valid.
        RememberMe::removeAllByUsername(Auth::getInstance()->getUser()->getUsername());
        $this->setRedirectUrl(Url::fromRequest());
    }
}