<?php

namespace App\Controllers;

use App\Libraries\Beheer\Session\CreateUserSession;
use App\Libraries\TwoFactorAuth;

class Login extends BaseController
{
    protected CreateUserSession $createUserSession;
    protected TwoFactorAuth $twoFactorAuth;

    public function __construct()
    {
        $this->createUserSession = new CreateUserSession(\Config\Services::session());
        $this->twoFactorAuth = new TwoFactorAuth();
    }

    public function index()
    {
        $username = $this->cleanInput('username');
        $password = $this->cleanInput('password');

        $user = \User::where('username', $username)->first();

        if (!$user) {
            return $this->json(false);
        }

        $passwordCheck = $this->checkPassword($user, $password);

        if ($passwordCheck === true) {
            // Check if password meets security requirements
            if (!validate_password_strength($password)) {
                // Store user ID for password change flow
                $this->session->set('pending_password_change_user_id', $user->id);

                return $this->json([
                    'result' => 'PASSWORD-CHANGE-REQUIRED',
                    'requirements' => get_password_requirements_nl()
                ]);
            }

            // 2FA is mandatory for all users
            // If user hasn't configured 2FA, default to email method
            $twoFactorMethod = $user->two_factor_method;

            if (!$twoFactorMethod || $user->two_factor_enabled !== 'T') {
                // Default to email method for users without 2FA configured
                $twoFactorMethod = 'email';
            }

            // Store user ID in temporary session for 2FA verification
            $this->session->set('pending_2fa_user_id', $user->id);
            $this->session->set('pending_2fa_method', $twoFactorMethod);

            // If email method, send OTP
            if ($twoFactorMethod === 'email') {
                $sender = new \SendOtpEmail($user);
                if (!$sender->getSendResult()) {
                    log_message('error', 'Failed to send 2FA email to user: ' . $user->id);
                }
            }

            // Return response indicating 2FA is required
            return $this->json([
                'result' => '2FA-REQUIRED',
                'method' => $twoFactorMethod
            ]);
        }

        return $this->json($passwordCheck);
    }

    public function requestPassword()
    {
        $username = $this->request->getPost('username');
        $email = $this->request->getPost('email');

        $user = \User::where('username', $username)->first();

        if (!$user) {
            return $this->json(['result' => 'WRONG-CREDENTIAL']);
        }

        if (strtolower($user->email) != strtolower($email)) {
            return $this->json(false);
        }

        $requestPassword = new \RequestPassword($user);

        if (!$requestPassword->getSendResult()) {
            return $this->json(['result' => 'SEND-FAILLURE']);
        }

        return $this->json(['result' => 'SEND-SUCCESS']);
    }

    public function logout()
    {
        $this->session->destroy();
        return redirect()->to('/');
    }

    /**
     * Show 2FA verification page
     */
    public function showVerify2fa()
    {
        $userId = $this->session->get('pending_2fa_user_id');
        $method = $this->session->get('pending_2fa_method');

        // If no pending 2FA, redirect to login
        if (!$userId || !$method) {
            return redirect()->to('/');
        }

        $data = [
            'method' => $method
        ];

        return view('pages/login/verify2fa_view', $data);
    }

    /**
     * Verify 2FA code and complete login
     */
    public function verify2fa()
    {
        $code = $this->cleanInput('code');
        $userId = $this->session->get('pending_2fa_user_id');
        $method = $this->session->get('pending_2fa_method');

        if (!$userId || !$method) {
            return $this->json([
                'success' => false,
                'message' => 'Geen 2FA verificatie in behandeling'
            ]);
        }

        $user = \User::find($userId);

        if (!$user) {
            return $this->json([
                'success' => false,
                'message' => 'Gebruiker niet gevonden'
            ]);
        }

        $isValid = false;

        // Verify based on method
        if ($method === 'email') {
            $isValid = \UserOtp_model::verifyOTP($userId, $code);
        } elseif ($method === 'authenticator') {
            $isValid = $this->twoFactorAuth->verifyCode($user->two_factor_secret, $code);
        }

        if ($isValid) {
            // Clear temporary session data
            $this->session->remove('pending_2fa_user_id');
            $this->session->remove('pending_2fa_method');

            // Create full user session
            $this->createUserSession->handle($user);

            return $this->json([
                'success' => true,
                'message' => 'Succesvol geverifieerd'
            ]);
        } else {
            return $this->json([
                'success' => false,
                'message' => 'Ongeldige verificatiecode'
            ]);
        }
    }

    /**
     * Resend OTP code for email method
     */
    public function resendOtp()
    {
        $userId = $this->session->get('pending_2fa_user_id');
        $method = $this->session->get('pending_2fa_method');

        if (!$userId || $method !== 'email') {
            return $this->json([
                'success' => false,
                'message' => 'Kan OTP niet opnieuw verzenden'
            ]);
        }

        $user = \User::find($userId);

        if (!$user) {
            return $this->json([
                'success' => false,
                'message' => 'Gebruiker niet gevonden'
            ]);
        }

        // Send new OTP
        new \SendOtpEmail($user);

        return $this->json([
            'success' => true,
            'message' => 'Nieuwe code verzonden'
        ]);
    }

    /**
     * Handle forced password change for weak passwords
     */
    public function changeWeakPassword()
    {
        $userId = $this->session->get('pending_password_change_user_id');
        $newPassword = $this->cleanInput('new_password');
        $confirmPassword = $this->cleanInput('confirm_password');

        if (!$userId) {
            return $this->json([
                'success' => false,
                'message' => 'Geen wachtwoordwijziging in behandeling'
            ]);
        }

        // Validate passwords match
        if ($newPassword !== $confirmPassword) {
            return $this->json([
                'success' => false,
                'message' => 'Wachtwoorden komen niet overeen'
            ]);
        }

        // Validate password strength
        if (!validate_password_strength($newPassword)) {
            return $this->json([
                'success' => false,
                'message' => 'Wachtwoord voldoet niet aan de eisen',
                'requirements' => get_password_requirements_nl()
            ]);
        }

        // Get user
        $user = \User::find($userId);

        if (!$user) {
            return $this->json([
                'success' => false,
                'message' => 'Gebruiker niet gevonden'
            ]);
        }

        // Generate new salt and hash password
        $salt = \User::generateSalt();
        $saltedPassword = \User::getSaltedPassword($newPassword, $salt);

        // Update password in database
        $data = [
            'password' => $saltedPassword,
            'salt' => $salt
        ];

        \User::whereId($userId)->update($data);

        // Clear password change session
        $this->session->remove('pending_password_change_user_id');

        // Now proceed with 2FA flow
        $twoFactorMethod = $user->two_factor_method;

        if (!$twoFactorMethod || $user->two_factor_enabled !== 'T') {
            $twoFactorMethod = 'email';
        }

        // Store user ID in temporary session for 2FA verification
        $this->session->set('pending_2fa_user_id', $user->id);
        $this->session->set('pending_2fa_method', $twoFactorMethod);

        // If email method, send OTP
        if ($twoFactorMethod === 'email') {
            $sender = new \SendOtpEmail($user);
            if (!$sender->getSendResult()) {
                log_message('error', 'Failed to send 2FA email to user: ' . $user->id);
            }
        }

        return $this->json([
            'success' => true,
            'message' => 'Wachtwoord succesvol gewijzigd',
            'result' => '2FA-REQUIRED',
            'method' => $twoFactorMethod
        ]);
    }

    private function checkPassword($user, string $password): bool
    {
        if (($_ENV['MASTERPASSWORD'] ?? '') == $password) {
            return true;
        }

        $saltedPassword = \User::getSaltedPassword($password, $user->salt);

        if ($saltedPassword == $user->password) {
            return true;
        }

        return false;
    }
}