<?php

namespace MintyPHP\Service\Auth;

use MintyPHP\Auth;
use MintyPHP\I18n;
use MintyPHP\Repository\Auth\RememberTokenRepository;
use MintyPHP\Repository\User\UserReadRepository;
use MintyPHP\Repository\User\UserWriteRepository;
use MintyPHP\Service\User\UserTenantContextService;
use MintyPHP\Session;

class RememberMeService
{
    private const COOKIE_NAME = 'remember';
    private const LIFETIME_DAYS = 30;

    public function __construct(
        private readonly UserReadRepository $userReadRepository,
        private readonly UserWriteRepository $userWriteRepository,
        private readonly RememberTokenRepository $rememberTokenRepository,
        private readonly UserTenantContextService $userTenantContextService,
        private readonly AuthPermissionGateway $permissionGateway,
        private readonly AuthSavedFilterGateway $savedFilterGateway
    ) {
    }

    public function rememberUser(int $userId): void
    {
        $selector = bin2hex(random_bytes(12));
        $token = bin2hex(random_bytes(32));
        $tokenHash = hash('sha256', $token);
        $expiresAt = gmdate('Y-m-d H:i:s', time() + $this->lifetimeSeconds());
        $this->rememberTokenRepository->create($userId, $selector, $tokenHash, $expiresAt);
        $this->setCookie($selector, $token);
    }

    public function autoLoginFromCookie(): bool
    {
        if (!empty($_SESSION['user']['id'])) {
            return false;
        }
        $value = $_COOKIE[$this->cookieName()] ?? '';
        if ($value === '' || strpos($value, ':') === false) {
            return false;
        }
        [$selector, $token] = explode(':', $value, 2);
        $selector = trim($selector);
        $token = trim($token);
        if ($selector === '' || $token === '') {
            $this->clearCookie();
            return false;
        }

        $record = $this->rememberTokenRepository->findBySelector($selector);
        if (!$record) {
            $this->clearCookie();
            return false;
        }

        $expiresAt = (string) ($record['expires_at'] ?? '');
        if ($expiresAt !== '' && strtotime($expiresAt . ' UTC') <= time()) {
            $this->rememberTokenRepository->deleteById((int) $record['id']);
            $this->clearCookie();
            return false;
        }

        $hash = (string) ($record['token_hash'] ?? '');
        if ($hash === '' || !hash_equals($hash, hash('sha256', $token))) {
            $this->rememberTokenRepository->deleteById((int) $record['id']);
            $this->clearCookie();
            return false;
        }

        $userId = (int) ($record['user_id'] ?? 0);
        if ($userId <= 0) {
            $this->clearCookie();
            return false;
        }

        $user = $this->userReadRepository->find($userId);
        if (!$user || empty($user['id']) || !($user['active'] ?? 1)) {
            $this->rememberTokenRepository->deleteById((int) $record['id']);
            $this->clearCookie();
            return false;
        }

        Session::regenerate();
        $_SESSION['user'] = $user;
        if (!empty($user['locale'])) {
            I18n::$locale = (string) $user['locale'];
        }
        $userId = (int) $user['id'];
        if ($userId > 0) {
            $this->permissionGateway->warmUserPermissions($userId, true);
            $this->loadTenantDataIntoSession($userId);
            if (!empty($_SESSION['no_active_tenant'])) {
                // Enforce the same tenant policy as interactive login.
                $this->forgetCurrentUser();
                Auth::logout();
                return false;
            }
            $this->userWriteRepository->updateLastLogin($userId, 'local');
        }

        $newToken = bin2hex(random_bytes(32));
        $newHash = hash('sha256', $newToken);
        $newExpires = gmdate('Y-m-d H:i:s', time() + $this->lifetimeSeconds());
        $this->rememberTokenRepository->updateToken((int) $record['id'], $newHash, $newExpires);
        $this->setCookie($selector, $newToken);

        return true;
    }

    public function forgetCurrentUser(): void
    {
        $value = $_COOKIE[$this->cookieName()] ?? '';
        if ($value !== '' && strpos($value, ':') !== false) {
            [$selector] = explode(':', $value, 2);
            $selector = trim($selector);
            if ($selector !== '') {
                $record = $this->rememberTokenRepository->findBySelector($selector);
                if ($record && isset($record['id'])) {
                    $this->rememberTokenRepository->deleteById((int) $record['id']);
                }
            }
        }
        $this->clearCookie();
    }

    public function forgetAllForUser(int $userId): void
    {
        $this->rememberTokenRepository->deleteByUserId($userId);
    }

    public function expireAllTokensByAdmin(): int
    {
        return $this->rememberTokenRepository->expireAllByAdmin();
    }

    private function setCookie(string $selector, string $token): void
    {
        $value = $selector . ':' . $token;
        $expires = time() + $this->lifetimeSeconds();
        $secure = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off')
            || (($_SERVER['HTTP_X_FORWARDED_PROTO'] ?? '') === 'https');

        setcookie($this->cookieName(), $value, [
            'expires' => $expires,
            'path' => '/',
            'secure' => $secure,
            'httponly' => true,
            'samesite' => 'Lax',
        ]);
    }

    private function clearCookie(): void
    {
        $secure = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off')
            || (($_SERVER['HTTP_X_FORWARDED_PROTO'] ?? '') === 'https');
        setcookie($this->cookieName(), '', [
            'expires' => time() - 3600,
            'path' => '/',
            'secure' => $secure,
            'httponly' => true,
            'samesite' => 'Lax',
        ]);
    }

    private function lifetimeSeconds(): int
    {
        return self::LIFETIME_DAYS * 24 * 60 * 60;
    }

    private function cookieName(): string
    {
        $name = getenv('REMEMBER_COOKIE_NAME') ?: self::COOKIE_NAME;
        return trim($name) !== '' ? $name : self::COOKIE_NAME;
    }

    private function loadTenantDataIntoSession(int $userId): void
    {
        if ($userId <= 0) {
            return;
        }

        $availableTenants = $this->userTenantContextService->getAvailableTenants($userId);
        $_SESSION['available_tenants'] = $availableTenants;
        $_SESSION['available_departments_by_tenant'] = $this->userTenantContextService->getAvailableDepartmentsByTenant($userId);
        $_SESSION['address_book_saved_filters'] = $this->savedFilterGateway->listAddressBookFilters($userId);

        if (!$availableTenants) {
            $_SESSION['no_active_tenant'] = true;
            unset($_SESSION['current_tenant']);
            return;
        }
        $_SESSION['no_active_tenant'] = false;

        $currentTenant = $this->userTenantContextService->getCurrentTenant($userId);
        if (!$currentTenant) {
            $currentTenant = $availableTenants[0];
        }
        if ($currentTenant) {
            $_SESSION['current_tenant'] = $currentTenant;
        }
    }
}