<?php

namespace App\Console\Commands;

use App\Enums\Portal;
use App\Models\Company;
use App\Models\PressRelease;
use App\Models\PressReleaseImage;
use App\Services\Image\ImageService;
use Illuminate\Console\Command;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\File;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Str;

class MigrateLegacyMedia extends Command
{
    protected $signature = 'legacy:migrate-media
                            {--portal=all : Portal (presseecho|businessportal24|all)}
                            {--type=all : Medientyp (company-logos|press-release-images|all)}
                            {--base-path=dev/migration : Lokaler Ordner mit den Legacy-Dateien}
                            {--dry-run : Nur prüfen, nichts kopieren oder aktualisieren}
                            {--force : Bereits migrierte Dateien erneut überschreiben}
                            {--limit=0 : Maximal N Legacy-Datensätze pro Typ und Portal verarbeiten (0 = alle)}';

    protected $description = 'Migriert Legacy-Firmenlogos und Pressemitteilungsbilder anhand der Legacy-DB in den finalen Storage.';

    private const PORTAL_CONNECTIONS = [
        'presseecho' => 'mysql_presseecho',
        'businessportal24' => 'mysql_businessportal',
    ];

    /**
     * @var array<string, list<string>>
     */
    private const SOURCE_DIRECTORIES = [
        'company-logos' => [
            'uploads/company',
            'thumbnails/company',
        ],
        'press-release-images' => [
            'uploads/pressreleaseimage',
            'uploads/pressreleaseimage_',
            'uploads/_pressreleaseimage',
            'thumbnails/pressreleaseimage',
        ],
    ];

    public function __construct(private readonly ImageService $imageService)
    {
        parent::__construct();
    }

    public function handle(): int
    {
        $portals = $this->selectedPortals();
        $types = $this->selectedTypes();

        if ($portals === []) {
            $this->error('Ungültiges Portal. Erlaubt: presseecho, businessportal24, all.');

            return self::FAILURE;
        }

        if ($types === []) {
            $this->error('Ungültiger Medientyp. Erlaubt: company-logos, press-release-images, all.');

            return self::FAILURE;
        }

        $configuredBasePath = (string) $this->option('base-path');
        $basePath = Str::startsWith($configuredBasePath, '/')
            ? rtrim($configuredBasePath, '/')
            : base_path(trim($configuredBasePath, '/'));
        $dryRun = (bool) $this->option('dry-run');
        $force = (bool) $this->option('force');
        $limit = max(0, (int) $this->option('limit'));
        $totals = $this->emptyStats();

        foreach ($portals as $portal) {
            foreach ($types as $type) {
                $stats = match ($type) {
                    'company-logos' => $this->migrateCompanyLogos($portal, $basePath, $dryRun, $force, $limit),
                    'press-release-images' => $this->migratePressReleaseImages($portal, $basePath, $dryRun, $force, $limit),
                };

                foreach ($totals as $key => $value) {
                    $totals[$key] = $value + $stats[$key];
                }

                $this->line(sprintf(
                    '%s/%s: Legacy %d, migriert %d, Thumbnail-Fallback %d, DB-Updates %d, bereits synchron %d, Ziel fehlt %d, Datei fehlt %d',
                    $portal,
                    $type,
                    $stats['legacy_rows'],
                    $stats['migrated'],
                    $stats['thumbnail_fallback'],
                    $stats['updated'],
                    $stats['already_synced'],
                    $stats['missing_target'],
                    $stats['missing_file'],
                ));
            }
        }

        $this->newLine();
        $this->info(sprintf(
            'Gesamt: Legacy %d, migriert %d, Thumbnail-Fallback %d, DB-Updates %d, bereits synchron %d, Ziel fehlt %d, Datei fehlt %d%s',
            $totals['legacy_rows'],
            $totals['migrated'],
            $totals['thumbnail_fallback'],
            $totals['updated'],
            $totals['already_synced'],
            $totals['missing_target'],
            $totals['missing_file'],
            $dryRun ? ' (Dry-Run)' : '',
        ));

        return ($totals['missing_target'] + $totals['missing_file']) > 0
            ? self::FAILURE
            : self::SUCCESS;
    }

    /**
     * @return array{legacy_rows:int,migrated:int,thumbnail_fallback:int,updated:int,already_synced:int,missing_target:int,missing_file:int}
     */
    private function migrateCompanyLogos(string $portal, string $basePath, bool $dryRun, bool $force, int $limit): array
    {
        $stats = $this->emptyStats();
        $sourceIndex = $this->sourceIndex($basePath, $portal, 'company-logos');
        $processed = 0;

        DB::connection(self::PORTAL_CONNECTIONS[$portal])
            ->table('company')
            ->whereNotNull('logo')
            ->where('logo', '!=', '')
            ->orderBy('id')
            ->chunk(500, function ($rows) use ($portal, $sourceIndex, $dryRun, $force, $limit, &$processed, &$stats): bool {
                foreach ($rows as $row) {
                    if ($limit > 0 && $processed >= $limit) {
                        return false;
                    }

                    $processed++;
                    $stats['legacy_rows']++;

                    $company = Company::withoutGlobalScopes()
                        ->where('legacy_portal', $portal)
                        ->where('legacy_id', $row->id)
                        ->first(['id', 'logo_path', 'logo_variants']);

                    if (! $company) {
                        $stats['missing_target']++;
                        $this->warn("Ziel fehlt: {$portal}/company/{$row->id}");

                        continue;
                    }

                    $sourceFilename = $this->legacyFilename((string) $row->logo);
                    $sourcePath = $sourceIndex[$sourceFilename] ?? $sourceIndex[Str::lower($sourceFilename)] ?? null;
                    $destinationPath = "company-logos/{$portal}/{$company->id}/{$sourceFilename}";

                    if ($this->isAlreadySynced($company->logo_path, $destinationPath, $force)) {
                        $stats['already_synced']++;

                        if (! $dryRun && (! is_array($company->logo_variants) || $company->logo_variants === [])) {
                            $variants = $this->imageService->generateMissingCompanyLogoVariants($destinationPath);

                            if ($variants !== []) {
                                $company->forceFill(['logo_variants' => $variants])->save();
                                $stats['updated']++;
                            }
                        }

                        continue;
                    }

                    if (! $sourcePath) {
                        $stats['missing_file']++;
                        $this->warn("Datei fehlt: {$portal}/company/{$sourceFilename} (Company #{$company->id})");

                        continue;
                    }

                    if (! $dryRun) {
                        $this->copyToPublicStorage($sourcePath, $destinationPath, $force);
                        $company->forceFill([
                            'logo_path' => $destinationPath,
                            'logo_variants' => $this->imageService->generateMissingCompanyLogoVariants($destinationPath),
                        ])->save();
                    }

                    $stats['migrated']++;
                    $stats['updated']++;
                }

                return true;
            });

        return $stats;
    }

    /**
     * @return array{legacy_rows:int,migrated:int,thumbnail_fallback:int,updated:int,already_synced:int,missing_target:int,missing_file:int}
     */
    private function migratePressReleaseImages(string $portal, string $basePath, bool $dryRun, bool $force, int $limit): array
    {
        $stats = $this->emptyStats();
        $sourceIndex = $this->sourceIndex($basePath, $portal, 'press-release-images');
        $thumbnailIndex = $this->thumbnailIndex($basePath, $portal);
        $processed = 0;

        DB::connection(self::PORTAL_CONNECTIONS[$portal])
            ->table('press_release_image')
            ->orderBy('id')
            ->chunk(500, function ($rows) use ($portal, $sourceIndex, $thumbnailIndex, $dryRun, $force, $limit, &$processed, &$stats): bool {
                foreach ($rows as $row) {
                    if ($limit > 0 && $processed >= $limit) {
                        return false;
                    }

                    if (blank($row->image)) {
                        continue;
                    }

                    $processed++;
                    $stats['legacy_rows']++;

                    $pressRelease = PressRelease::withoutGlobalScopes()
                        ->where('legacy_portal', $portal)
                        ->where('legacy_id', $row->press_release_id)
                        ->first(['id']);

                    if (! $pressRelease) {
                        $stats['missing_target']++;
                        $this->warn("Ziel fehlt: {$portal}/press_release/{$row->press_release_id}");

                        continue;
                    }

                    $sourceFilename = $this->legacyFilename((string) $row->image);
                    $sourcePath = $sourceIndex[$sourceFilename] ?? $sourceIndex[Str::lower($sourceFilename)] ?? null;
                    $usedThumbnailFallback = false;

                    if (! $sourcePath) {
                        $sourcePath = $thumbnailIndex[(int) $row->id] ?? null;
                        $usedThumbnailFallback = $sourcePath !== null;
                    }

                    $destinationFilename = $usedThumbnailFallback ? basename($sourcePath) : $sourceFilename;
                    $destinationPath = "press-releases/{$pressRelease->id}/images/{$destinationFilename}";
                    $image = PressReleaseImage::withTrashed()
                        ->where('legacy_portal', $portal)
                        ->where('legacy_id', $row->id)
                        ->first();

                    if ($image && $this->isAlreadySynced($image->path, $destinationPath, $force)) {
                        $stats['already_synced']++;

                        if (! $dryRun && (! is_array($image->variants) || $image->variants === [])) {
                            $variants = $this->imageService->generateMissingPressReleaseVariants($destinationPath);

                            if ($variants !== []) {
                                $image->forceFill(['variants' => $variants])->save();
                                $stats['updated']++;
                            }
                        }

                        continue;
                    }

                    if (! $sourcePath) {
                        $stats['missing_file']++;
                        $this->warn("Datei fehlt: {$portal}/press_release_image/{$sourceFilename} (Image #{$row->id})");

                        continue;
                    }

                    if ($usedThumbnailFallback) {
                        $stats['thumbnail_fallback']++;
                    }

                    $variants = [];
                    $size = [null, null];
                    $mime = null;

                    if (! $dryRun) {
                        $this->copyToPublicStorage($sourcePath, $destinationPath, $force);
                        $variants = $this->imageService->generateMissingPressReleaseVariants($destinationPath);
                        $size = @getimagesize(Storage::disk('public')->path($destinationPath)) ?: [null, null];
                        $mime = File::mimeType($sourcePath) ?: null;

                        $image = $image ?: new PressReleaseImage;
                        $image->forceFill([
                            'press_release_id' => $pressRelease->id,
                            'disk' => 'public',
                            'path' => $destinationPath,
                            'variants' => $variants,
                            'title' => $row->title ?: null,
                            'description' => $row->description ?: null,
                            'copyright' => $row->copyright ?: null,
                            'is_preview' => (bool) $row->is_preview_image,
                            'sort_order' => 0,
                            'width' => is_int($size[0] ?? null) ? $size[0] : null,
                            'height' => is_int($size[1] ?? null) ? $size[1] : null,
                            'mime' => $mime,
                            'legacy_portal' => $portal,
                            'legacy_id' => $row->id,
                        ]);

                        if ($image->trashed()) {
                            $image->restore();
                        }

                        $image->save();
                    }

                    $stats['migrated']++;
                    $stats['updated']++;
                }

                return true;
            });

        return $stats;
    }

    /**
     * @return list<string>
     */
    private function selectedPortals(): array
    {
        $portal = (string) $this->option('portal');

        return match ($portal) {
            'all' => [Portal::Presseecho->value, Portal::Businessportal24->value],
            Portal::Presseecho->value, Portal::Businessportal24->value => [$portal],
            default => [],
        };
    }

    /**
     * @return list<string>
     */
    private function selectedTypes(): array
    {
        $type = (string) $this->option('type');

        return match ($type) {
            'all' => ['company-logos', 'press-release-images'],
            'company-logos', 'press-release-images' => [$type],
            default => [],
        };
    }

    /**
     * @return array{legacy_rows:int,migrated:int,thumbnail_fallback:int,updated:int,already_synced:int,missing_target:int,missing_file:int}
     */
    private function emptyStats(): array
    {
        return [
            'legacy_rows' => 0,
            'migrated' => 0,
            'thumbnail_fallback' => 0,
            'updated' => 0,
            'already_synced' => 0,
            'missing_target' => 0,
            'missing_file' => 0,
        ];
    }

    /**
     * @return array<string, string>
     */
    private function sourceIndex(string $basePath, string $portal, string $type): array
    {
        $index = [];

        foreach (self::SOURCE_DIRECTORIES[$type] as $relativeDirectory) {
            $directory = "{$basePath}/{$portal}/{$relativeDirectory}";

            if (! File::isDirectory($directory)) {
                continue;
            }

            foreach (File::allFiles($directory) as $file) {
                $index[$file->getFilename()] ??= $file->getPathname();
                $index[Str::lower($file->getFilename())] ??= $file->getPathname();
            }
        }

        return $index;
    }

    /**
     * @return array<int, string>
     */
    private function thumbnailIndex(string $basePath, string $portal): array
    {
        $directory = "{$basePath}/{$portal}/thumbnails/pressreleaseimage";

        if (! File::isDirectory($directory)) {
            return [];
        }

        $index = [];
        $priorities = [
            'press_image_preview' => 50,
            'pressrelease_form' => 40,
            'backend_list' => 30,
            'press_image_list' => 20,
            'press_list_image' => 10,
        ];

        foreach (File::allFiles($directory) as $file) {
            if (! preg_match('/-(\d+)\.[^.]+$/', $file->getFilename(), $matches)) {
                continue;
            }

            $legacyImageId = (int) $matches[1];
            $thumbnailType = Str::after($file->getPathname(), "{$directory}/");
            $thumbnailType = Str::before($thumbnailType, DIRECTORY_SEPARATOR);
            $priority = $priorities[$thumbnailType] ?? 0;
            $current = $index[$legacyImageId] ?? null;

            if (! $current || $priority > ($current['priority'] ?? 0)) {
                $index[$legacyImageId] = [
                    'path' => $file->getPathname(),
                    'priority' => $priority,
                ];
            }
        }

        return collect($index)
            ->map(fn (array $entry): string => $entry['path'])
            ->all();
    }

    private function legacyFilename(string $path): string
    {
        $urlPath = parse_url($path, PHP_URL_PATH);
        $filename = basename(rawurldecode((string) ($urlPath ?: $path)));

        return Str::of($filename)->trim()->toString();
    }

    private function isAlreadySynced(?string $currentPath, string $destinationPath, bool $force): bool
    {
        return ! $force
            && $currentPath === $destinationPath
            && Storage::disk('public')->exists($destinationPath);
    }

    private function copyToPublicStorage(string $sourcePath, string $destinationPath, bool $force): void
    {
        if (! $force && Storage::disk('public')->exists($destinationPath)) {
            return;
        }

        $stream = fopen($sourcePath, 'rb');

        if ($stream === false) {
            throw new \RuntimeException("Quelldatei kann nicht gelesen werden: {$sourcePath}");
        }

        try {
            Storage::disk('public')->put($destinationPath, $stream, 'public');
        } finally {
            fclose($stream);
        }
    }
}