<?php

namespace App\Services\Import;

use App\Enums\Portal;
use App\Enums\RegistrationType;
use App\Models\LegacyImportMap;
use App\Models\Profile;
use App\Models\User;
use App\Services\Auth\UserRolePermissionSyncService;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

class UserImporter
{
    /** Legacy-Gruppen → Spatie-Rollen */
    private const GROUP_ROLE_MAP = [
        1 => 'admin',
        2 => 'editor',
        3 => 'api-only',
        4 => 'customer',
    ];

    private const DEFAULT_ROLE = 'customer';

    private const CHUNK_SIZE = 500;

    /** Registration-Type-Mapping aus Legacy-Wert */
    private const REG_TYPE_MAP = [
        'agency' => RegistrationType::Agency,
        'company' => RegistrationType::Company,
        'apiuser' => RegistrationType::ApiUser,
    ];

    public function __construct(
        private readonly UserRolePermissionSyncService $roleSync,
    ) {}

    public function run(ImportContext $ctx): ImportResult
    {
        $result = new ImportResult;
        $conn = $ctx->connection;
        $portal = $ctx->portalEnum;
        $legacyPortal = $ctx->legacyPortalValue();

        // Lade alle Gruppen-Zuordnungen in Memory (klein genug)
        $userGroups = DB::connection($conn)
            ->table('sf_guard_user_group')
            ->get()
            ->groupBy('user_id')
            ->map(fn ($rows) => $rows->pluck('group_id')->first());

        DB::connection($conn)
            ->table('sf_guard_user')
            ->join('sf_guard_user_profile', 'sf_guard_user.id', '=', 'sf_guard_user_profile.user_id')
            ->select([
                'sf_guard_user.id as legacy_id',
                'sf_guard_user.username',
                'sf_guard_user.is_active',
                'sf_guard_user.is_super_admin',
                'sf_guard_user.last_login',
                'sf_guard_user.ip_address',
                'sf_guard_user.created_at',
                'sf_guard_user.updated_at',
                'sf_guard_user_profile.email',
                'sf_guard_user_profile.salutation_id',
                'sf_guard_user_profile.title',
                'sf_guard_user_profile.first_name',
                'sf_guard_user_profile.last_name',
                'sf_guard_user_profile.address',
                'sf_guard_user_profile.country_id',
                'sf_guard_user_profile.phone',
                'sf_guard_user_profile.birthdate',
                'sf_guard_user_profile.language',
                'sf_guard_user_profile.backlink_url',
                'sf_guard_user_profile.show_stats',
                'sf_guard_user_profile.validation_date',
                'sf_guard_user_profile.contract_date',
                'sf_guard_user_profile.registration_type',
                'sf_guard_user_profile.validate',
                'sf_guard_user_profile.tax_id_number',
                'sf_guard_user_profile.tax_exempt',
                'sf_guard_user_profile.tax_exempt_reason',
                'sf_guard_user_profile.disable_footer_code',
            ])
            ->orderBy('sf_guard_user.id')
            ->chunk(self::CHUNK_SIZE, function ($rows) use ($ctx, $result, $portal, $legacyPortal, $userGroups): void {
                foreach ($rows as $row) {
                    try {
                        $this->importRow($row, $ctx, $result, $portal, $legacyPortal, $userGroups);
                    } catch (\Throwable $e) {
                        $result->addError("User legacy_id={$row->legacy_id}: {$e->getMessage()}");
                    }
                }
            });

        return $result;
    }

    private function importRow(
        object $row,
        ImportContext $ctx,
        ImportResult $result,
        Portal $portal,
        string $legacyPortal,
        Collection $userGroups,
    ): void {
        // E-Mail-Adresse ist Pflicht
        $email = trim((string) $row->email);
        if (blank($email) || ! filter_var($email, FILTER_VALIDATE_EMAIL)) {
            $result->incrementSkipped();

            return;
        }

        // Idempotenz-Check via legacy_import_map
        $alreadyImported = LegacyImportMap::query()
            ->where('legacy_portal', $legacyPortal)
            ->where('legacy_table', 'sf_guard_user')
            ->where('legacy_id', $row->legacy_id)
            ->exists();

        if ($alreadyImported && ! $ctx->force) {
            $result->incrementSkipped();

            return;
        }

        if ($ctx->dryRun) {
            $result->incrementImported();

            return;
        }

        $name = trim(($row->first_name ?? '').' '.($row->last_name ?? ''));
        if (blank($name)) {
            $name = $row->username;
        }

        $language = in_array($row->language, ['de', 'en']) ? $row->language : 'de';

        $regType = self::REG_TYPE_MAP[$row->registration_type] ?? RegistrationType::ExistingLegacy;

        $user = User::withoutTimestamps(function () use ($email, $name, $portal, $regType, $language, $row, $legacyPortal): User {
            return User::query()->updateOrCreate(
                ['email' => $email],
                [
                    'name' => $name,
                    'portal' => $portal->value,
                    'registration_type' => $regType->value,
                    'language' => $language,
                    'is_active' => (bool) $row->is_active,
                    'is_super_admin' => (bool) $row->is_super_admin,
                    'last_login_at' => $row->last_login ?: null,
                    'last_login_ip' => $row->ip_address ?: null,
                    'legacy_portal' => $legacyPortal,
                    'legacy_id' => $row->legacy_id,
                    'created_at' => $row->created_at ?? now(),
                    'updated_at' => $row->updated_at ?? $row->created_at ?? now(),
                    // Kein Passwort – User erhält Go-Live-Reset-Mail (D-09)
                ]
            );
        });

        // Rolle zuweisen
        $groupId = $userGroups->get($row->legacy_id);
        $roleName = self::GROUP_ROLE_MAP[$groupId] ?? self::DEFAULT_ROLE;
        $this->roleSync->assignRoleAndSyncPermissions($user, $roleName);

        Profile::query()->updateOrCreate(
            ['user_id' => $user->id],
            [
                'salutation_key' => $this->mapSalutation((int) ($row->salutation_id ?? 0)),
                'title' => $this->cleanText($row->title ?? null, 80),
                'first_name' => $this->cleanText($row->first_name ?? null, 80),
                'last_name' => $this->cleanText($row->last_name ?? null, 80),
                'phone' => $this->cleanText($row->phone ?? null, 40),
                'address' => $this->cleanText($row->address ?? null, 1000),
                'country_code' => $this->mapCountry((int) ($row->country_id ?? 0)),
                'birthdate' => $this->validDateOrNull($row->birthdate ?? null),
                'backlink_url' => $this->cleanText($row->backlink_url ?? null, 255),
                'show_stats' => (bool) ($row->show_stats ?? false),
                'validation_date' => $this->validDateOrNull($row->validation_date ?? null),
                'contract_date' => $this->validDateOrNull($row->contract_date ?? null),
                'validate_token' => $this->cleanText($row->validate ?? null, 64),
                'tax_id_number' => $this->cleanText($row->tax_id_number ?? null, 255),
                'tax_exempt' => (bool) ($row->tax_exempt ?? false),
                'tax_exempt_reason' => $this->cleanText($row->tax_exempt_reason ?? null, 1000),
                'disable_footer_code' => (bool) ($row->disable_footer_code ?? false),
            ]
        );

        // Import-Map eintragen
        LegacyImportMap::query()->updateOrCreate(
            [
                'legacy_portal' => $legacyPortal,
                'legacy_table' => 'sf_guard_user',
                'legacy_id' => $row->legacy_id,
            ],
            [
                'target_table' => 'users',
                'target_id' => $user->id,
                'imported_at' => now(),
            ]
        );

        if ($alreadyImported) {
            $result->incrementUpdated();
        } else {
            $result->incrementImported();
        }
    }

    private function mapSalutation(int $salutationId): ?string
    {
        return match ($salutationId) {
            1 => 'mr',
            2 => 'mrs',
            3 => 'none',
            default => null,
        };
    }

    private function mapCountry(int $countryId): ?string
    {
        return match ($countryId) {
            177 => 'DE',
            80 => 'AT',
            196 => 'CH',
            115 => 'LI',
            117 => 'LU',
            21 => 'BE',
            2 => 'NL',
            165 => 'FR',
            30 => 'GB',
            229 => 'US',
            default => null,
        };
    }

    private function cleanText(?string $value, int $maxLength): ?string
    {
        if (blank($value)) {
            return null;
        }

        $clean = html_entity_decode((string) $value, ENT_QUOTES | ENT_HTML5, 'UTF-8');
        $clean = preg_replace('/[\x00-\x1F\x7F\xC2\xA0]/u', ' ', $clean) ?? $clean;
        $clean = trim((string) $clean);

        return blank($clean) ? null : mb_substr($clean, 0, $maxLength);
    }

    private function validDateOrNull(mixed $value): ?string
    {
        if (blank($value) || str_starts_with((string) $value, '0000-00-00')) {
            return null;
        }

        return (string) $value;
    }
}