<?php

namespace App\Services\Import;

use App\Enums\Portal;
use App\Enums\PressReleaseStatus;
use App\Models\LegacyImportMap;
use App\Models\PressRelease;
use App\Models\PressReleaseImage;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;

class PressReleaseImporter
{
    private const CHUNK_SIZE = 200;

    /** Legacy-Status → neuer Status */
    private const STATUS_MAP = [
        'new' => PressReleaseStatus::Draft,
        'edited' => PressReleaseStatus::Draft,
        'prepublished' => PressReleaseStatus::Review,
        'published' => PressReleaseStatus::Published,
        'rejected' => PressReleaseStatus::Rejected,
    ];

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

        // Bilder und Kontakt-Pivots vorladen
        $images = DB::connection($conn)
            ->table('press_release_image')
            ->get()
            ->groupBy('press_release_id');

        $prContacts = DB::connection($conn)
            ->table('press_release_contact')
            ->get()
            ->groupBy('press_release_id');

        DB::connection($conn)
            ->table('press_release')
            ->orderBy('id')
            ->chunk(self::CHUNK_SIZE, function ($rows) use ($ctx, $result, $legacyPortal, $portal, $images, $prContacts): void {
                foreach ($rows as $row) {
                    try {
                        $this->importRow($row, $ctx, $result, $legacyPortal, $portal, $images, $prContacts);
                    } catch (\Throwable $e) {
                        $result->addError("PR legacy_id={$row->id}: {$e->getMessage()}");
                    }
                }
            });

        return $result;
    }

    private function importRow(
        object $row,
        ImportContext $ctx,
        ImportResult $result,
        string $legacyPortal,
        Portal $portal,
        Collection $images,
        Collection $prContacts,
    ): void {
        $alreadyImported = LegacyImportMap::query()
            ->where('legacy_portal', $legacyPortal)
            ->where('legacy_table', 'press_release')
            ->where('legacy_id', $row->id)
            ->exists();

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

            return;
        }

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

            return;
        }

        // User aus Import-Map
        $userId = null;
        if ($row->user_id) {
            $userMap = LegacyImportMap::query()
                ->where('legacy_portal', $legacyPortal)
                ->where('legacy_table', 'sf_guard_user')
                ->where('legacy_id', $row->user_id)
                ->first();
            $userId = $userMap?->target_id;
        }

        if (! $userId) {
            $result->incrementSkipped();

            return;
        }

        // Company aus Import-Map
        $companyId = null;
        if ($row->company_id) {
            $companyMap = LegacyImportMap::query()
                ->where('legacy_portal', $legacyPortal)
                ->where('legacy_table', 'company')
                ->where('legacy_id', $row->company_id)
                ->first();
            $companyId = $companyMap?->target_id;
        }

        // Kategorie aus Import-Map
        $categoryId = null;
        if ($row->category_id) {
            $catMap = LegacyImportMap::query()
                ->where('legacy_table', 'category')
                ->where('legacy_id', $row->category_id)
                ->first();
            $categoryId = $catMap?->target_id;
        }

        // Fallback-Kategorie (erste verfügbare)
        if (! $categoryId) {
            $categoryId = LegacyImportMap::query()
                ->where('legacy_table', 'category')
                ->value('target_id');
        }

        if (! $categoryId) {
            $result->incrementSkipped();

            return;
        }

        $status = self::STATUS_MAP[$row->status] ?? PressReleaseStatus::Draft;
        $language = in_array($row->language, ['de', 'en']) ? $row->language : 'de';

        // Beim Update (--force): bestehenden Slug behalten, um Kollisionen zu vermeiden.
        $existingPr = $alreadyImported
            ? PressRelease::withoutGlobalScopes()
                ->where('legacy_portal', $legacyPortal)
                ->where('legacy_id', $row->id)
                ->first(['id', 'slug'])
            : null;

        $slug = $existingPr?->slug ?? $this->uniqueSlug(
            $row->slug ?: Str::slug($row->title) ?: 'pressemitteilung',
            $portal->value,
            $language,
            $existingPr?->id,
        );

        $publishedAt = ($status === PressReleaseStatus::Published)
            ? ($row->updated_at ?? $row->created_at)
            : null;

        $pr = PressRelease::withoutTimestamps(function () use (
            $legacyPortal, $row, $portal, $userId, $companyId, $categoryId,
            $language, $slug, $status, $publishedAt,
        ): PressRelease {
            return PressRelease::withoutGlobalScopes()->updateOrCreate(
                ['legacy_portal' => $legacyPortal, 'legacy_id' => $row->id],
                [
                    'uuid' => (string) Str::uuid(),
                    'portal' => $portal->value,
                    'user_id' => $userId,
                    'company_id' => $companyId,
                    'category_id' => $categoryId,
                    'language' => $language,
                    'title' => $row->title ?: 'Ohne Titel',
                    'slug' => $slug,
                    'text' => $row->text ?: '',
                    'backlink_url' => $row->backlink_url ?: null,
                    'keywords' => $row->keywords ?: null,
                    'status' => $status->value,
                    'hits' => max(0, (int) $row->hits),
                    'teaser_begin' => max(0, (int) ($row->teaser_begin ?? 0)),
                    'teaser_end' => max(0, (int) ($row->teaser_end ?? 0)),
                    'no_export' => (bool) ($row->no_export ?? false),
                    'published_at' => $publishedAt,
                    'created_at' => $row->created_at ?? now(),
                    'updated_at' => $row->updated_at ?? $row->created_at ?? now(),
                ]
            );
        });

        foreach ($images->get($row->id, []) as $img) {
            PressReleaseImage::withoutGlobalScopes()->updateOrCreate(
                ['legacy_portal' => $legacyPortal, 'legacy_id' => $img->id],
                [
                    'press_release_id' => $pr->id,
                    'path' => $img->image,
                    'title' => $img->title ?: null,
                    'description' => $img->description ?: null,
                    'copyright' => $img->copyright ?: null,
                    'is_preview' => (bool) $img->is_preview_image,
                    'sort_order' => 0,
                ]
            );
        }

        // Kontakt-Pivot importieren
        $contactIds = [];
        foreach ($prContacts->get($row->id, []) as $pivot) {
            $contactMap = LegacyImportMap::query()
                ->where('legacy_portal', $legacyPortal)
                ->where('legacy_table', 'contact')
                ->where('legacy_id', $pivot->contact_id)
                ->first();

            if ($contactMap) {
                $contactIds[] = $contactMap->target_id;
            }
        }

        if ($contactIds !== []) {
            $pr->contacts()->syncWithoutDetaching($contactIds);
        }

        LegacyImportMap::query()->updateOrCreate(
            [
                'legacy_portal' => $legacyPortal,
                'legacy_table' => 'press_release',
                'legacy_id' => $row->id,
            ],
            [
                'target_table' => 'press_releases',
                'target_id' => $pr->id,
                'imported_at' => now(),
            ]
        );

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

    private function uniqueSlug(string $base, string $portal, string $language, ?int $excludeId = null): string
    {
        $slug = $base;
        $i = 2;

        while (PressRelease::withoutGlobalScopes()
            ->where('portal', $portal)
            ->where('language', $language)
            ->where('slug', $slug)
            ->when($excludeId, fn ($q) => $q->where('id', '!=', $excludeId))
            ->exists()
        ) {
            $slug = $base.'-'.$i++;
        }

        return $slug;
    }
}