<?php

namespace App\Controllers;

use App\Core\BaseController;
use App\Models\User;
use App\Models\PasswordReset;

class AuthController extends BaseController
{
    public function showLogin(): string
    {
        if ($this->session->isLoggedIn()) {
            return $this->redirect('/dashboard');
        }

        return $this->render('auth/login');
    }

    public function login(): Response
    {
        $email = $this->request->post('email');
        $password = $this->request->post('password');

        // Check if account is locked
        if ($this->session->isLockedOut()) {
            $this->flash('error', 'Account ist gesperrt. Bitte warten Sie 15 Minuten.');
            return $this->redirect('/login');
        }

        // Validate input
        $errors = $this->validate([
            'email' => 'required|email',
            'password' => 'required'
        ]);

        if (!empty($errors)) {
            foreach ($errors as $field => $fieldErrors) {
                foreach ($fieldErrors as $error) {
                    $this->flash('error', $error);
                }
            }
            return $this->redirect('/login');
        }

        // Find user
        $user = (new User($this->database))->findByEmail($email);

        if (!$user || !$user['active']) {
            $this->incrementLoginAttempts();
            $this->flash('error', 'Ungültige Anmeldedaten oder Account inaktiv.');
            return $this->redirect('/login');
        }

        // Verify password
        if (!password_verify($password, $user['passhash'])) {
            $this->incrementLoginAttempts();
            $this->flash('error', 'Ungültige Anmeldedaten.');
            return $this->redirect('/login');
        }

        // Check if password needs rehash
        if (password_needs_rehash($user['passhash'], PASSWORD_ARGON2ID)) {
            $newHash = password_hash($password, PASSWORD_ARGON2ID);
            (new User($this->database))->update($user['id'], ['passhash' => $newHash]);
        }

        // Reset login attempts
        $this->session->setLoginAttempts(0);

        // Set user session
        $this->session->setUser($user);
        $this->session->setLastActivity();

        // Log audit
        $this->logAudit('login', 'users', $user['id']);

        $this->flash('success', 'Erfolgreich angemeldet.');
        return $this->redirect('/dashboard');
    }

    public function logout(): Response
    {
        if ($this->session->isLoggedIn()) {
            $userId = $this->session->getUserId();
            $this->logAudit('logout', 'users', $userId);
        }

        $this->session->logout();
        $this->flash('success', 'Erfolgreich abgemeldet.');
        return $this->redirect('/login');
    }

    public function showForgotPassword(): string
    {
        return $this->render('auth/forgot-password');
    }

    public function forgotPassword(): Response
    {
        $email = $this->request->post('email');

        $errors = $this->validate([
            'email' => 'required|email'
        ]);

        if (!empty($errors)) {
            foreach ($errors as $field => $fieldErrors) {
                foreach ($fieldErrors as $error) {
                    $this->flash('error', $error);
                }
            }
            return $this->redirect('/password/forgot');
        }

        $user = (new User($this->database))->findByEmail($email);

        if ($user && $user['active']) {
            $token = bin2hex(random_bytes(32));
            $expiresAt = date('Y-m-d H:i:s', strtotime('+1 hour'));

            $passwordReset = new PasswordReset($this->database);
            $passwordReset->create([
                'user_id' => $user['id'],
                'token' => $token,
                'expires_at' => $expiresAt
            ]);

            // Send email (in production, implement email service)
            // $this->sendPasswordResetEmail($user['email'], $token);
        }

        // Always show success message for security
        $this->flash('success', 'Falls die E-Mail-Adresse existiert, wurde ein Reset-Link gesendet.');
        return $this->redirect('/login');
    }

    public function showResetPassword(): string
    {
        $token = $this->request->get('token');
        
        if (!$token) {
            $this->flash('error', 'Ungültiger Reset-Link.');
            return $this->redirect('/login');
        }

        $passwordReset = new PasswordReset($this->database);
        $reset = $passwordReset->findByToken($token);

        if (!$reset || strtotime($reset['expires_at']) < time()) {
            $this->flash('error', 'Reset-Link ist ungültig oder abgelaufen.');
            return $this->redirect('/login');
        }

        return $this->render('auth/reset-password', ['token' => $token]);
    }

    public function resetPassword(): Response
    {
        $token = $this->request->post('token');
        $password = $this->request->post('password');
        $passwordConfirm = $this->request->post('password_confirm');

        $errors = $this->validate([
            'password' => 'required|min:8',
            'password_confirm' => 'required'
        ]);

        if ($password !== $passwordConfirm) {
            $this->flash('error', 'Passwörter stimmen nicht überein.');
            return $this->redirect('/password/reset?token=' . $token);
        }

        if (!empty($errors)) {
            foreach ($errors as $field => $fieldErrors) {
                foreach ($fieldErrors as $error) {
                    $this->flash('error', $error);
                }
            }
            return $this->redirect('/password/reset?token=' . $token);
        }

        $passwordReset = new PasswordReset($this->database);
        $reset = $passwordReset->findByToken($token);

        if (!$reset || strtotime($reset['expires_at']) < time()) {
            $this->flash('error', 'Reset-Link ist ungültig oder abgelaufen.');
            return $this->redirect('/login');
        }

        // Update user password
        $userModel = new User($this->database);
        $userModel->update($reset['user_id'], [
            'passhash' => password_hash($password, PASSWORD_ARGON2ID)
        ]);

        // Delete used reset token
        $passwordReset->delete($reset['id']);

        $this->flash('success', 'Passwort erfolgreich geändert. Sie können sich jetzt anmelden.');
        return $this->redirect('/login');
    }

    private function incrementLoginAttempts(): void
    {
        $attempts = $this->session->getLoginAttempts();
        $this->session->setLoginAttempts($attempts + 1);
    }
}