<?php

namespace App\Console\Commands;

use App\Models\QrCode;
use App\Models\QrEventRegistration;
use App\Models\QrScanEvent;
use App\Models\QrTransaction;
use App\Models\QrWallet;
use App\Models\User;
use Illuminate\Console\Command;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Storage;

class ImportEventsCommand extends Command
{
    protected $signature = 'events:import
        {file : Path to events-export.json from the platform}
        {--commit : Actually write changes}
        {--storage-source= : Platform qr disk root (storage/app/private/qr) to copy event images}';

    protected $description = 'Import Events codes and registrations from the platform export';

    /** @var array<int,int> platform qr_code id → local id */
    private array $codeMap = [];

    public function handle(): int
    {
        $commit = (bool) $this->option('commit');

        if (! $commit) {
            $this->warn('DRY RUN — no changes will be written. Re-run with --commit to apply.');
        }

        $path = $this->argument('file');
        if (! is_file($path)) {
            $this->error("File not found: {$path}");

            return self::FAILURE;
        }

        $payload = json_decode((string) file_get_contents($path), true);
        if (! is_array($payload)) {
            $this->error('Invalid JSON export file.');

            return self::FAILURE;
        }

        $apply = function (callable $callback) use ($commit): void {
            if ($commit) {
                DB::transaction($callback);
            } else {
                $callback();
            }
        };

        $apply(function () use ($payload, $commit): void {
            foreach ($payload['qr_wallets'] ?? [] as $row) {
                $this->importWallet($row, $commit);
            }
            foreach ($payload['qr_codes'] ?? [] as $row) {
                $this->importCode($row, $commit);
            }
            if ($commit) {
                $this->remapAllProgrammeLinks();
            }
            foreach ($payload['qr_event_registrations'] ?? [] as $row) {
                $this->importRegistration($row, $commit);
            }
            foreach ($payload['qr_scan_events'] ?? [] as $row) {
                $this->importScanEvent($row, $commit);
            }
            foreach ($payload['qr_transactions'] ?? [] as $row) {
                $this->importTransaction($row, $commit);
            }
        });

        if (! $this->option('storage-source')) {
            $this->warn('Pass --storage-source=/path/to/platform/storage/app/private/qr to copy event cover/logo files.');
        }

        $this->info(($commit ? 'Imported' : 'Would import').' '.count($this->codeMap).' event code(s).');

        return self::SUCCESS;
    }

    private function resolveUser(array $row): ?User
    {
        $publicId = $row['owner_public_id'] ?? null;
        if (! $publicId) {
            return null;
        }

        return User::firstOrCreate(
            ['public_id' => $publicId],
            ['email' => $row['owner_email'] ?? $publicId.'@users.ladill.com', 'name' => 'Imported user'],
        );
    }

    /** @param array<string,mixed> $row */
    private function importWallet(array $row, bool $commit): void
    {
        $user = $this->resolveUser($row);
        if (! $user) {
            return;
        }

        $attrs = collect($row)->except(['platform_id', 'owner_public_id', 'owner_email', 'id', 'user_id'])->all();

        if ($commit) {
            QrWallet::updateOrCreate(['user_id' => $user->id], $attrs);
        }
    }

    /** @param array<string,mixed> $row */
    private function importCode(array $row, bool $commit): void
    {
        $user = $this->resolveUser($row);
        if (! $user) {
            return;
        }

        $platformId = (int) ($row['platform_id'] ?? 0);
        $shortCode = (string) ($row['short_code'] ?? '');
        $attrs = collect($row)->except([
            'platform_id',
            'owner_public_id',
            'owner_email',
            'id',
            'user_id',
        ])->all();
        $attrs['user_id'] = $user->id;
        $attrs = $this->normalizeJsonAttributes($attrs, ['payload']);

        if ($commit) {
            $code = QrCode::updateOrCreate(['short_code' => $shortCode], $attrs);
            $this->codeMap[$platformId] = $code->id;
            $this->copyCodeAssets($code);
        } else {
            $this->codeMap[$platformId] = $platformId;
        }
    }

    private function remapAllProgrammeLinks(): void
    {
        QrCode::query()
            ->where('type', QrCode::TYPE_EVENT)
            ->each(fn (QrCode $code) => $this->remapProgrammeLinks($code));
    }

    private function remapProgrammeLinks(QrCode $code): void
    {
        if ($code->type !== QrCode::TYPE_EVENT) {
            return;
        }

        $content = $code->content();
        $programmeId = (int) ($content['programme_qr_id'] ?? 0);
        if ($programmeId <= 0 || ! isset($this->codeMap[$programmeId])) {
            return;
        }

        $content['programme_qr_id'] = $this->codeMap[$programmeId];
        $payload = $code->payload ?? [];
        $payload['content'] = $content;
        $code->update(['payload' => $payload]);
    }

    /**
     * @param  array<string,mixed>  $attrs
     * @param  list<string>  $keys
     * @return array<string,mixed>
     */
    private function normalizeJsonAttributes(array $attrs, array $keys): array
    {
        foreach ($keys as $key) {
            if (! isset($attrs[$key]) || ! is_string($attrs[$key])) {
                continue;
            }

            $decoded = json_decode($attrs[$key], true);
            if (is_array($decoded)) {
                $attrs[$key] = $decoded;
            }
        }

        return $attrs;
    }

    /** @param array<string,mixed> $row */
    private function importRegistration(array $row, bool $commit): void
    {
        $platformCodeId = (int) ($row['platform_qr_code_id'] ?? 0);
        $localCodeId = $this->codeMap[$platformCodeId] ?? null;
        if (! $localCodeId) {
            return;
        }

        $reference = (string) ($row['reference'] ?? '');
        $attrs = collect($row)->except(['platform_id', 'platform_qr_code_id', 'id', 'qr_code_id', 'user_id'])->all();
        $attrs['qr_code_id'] = $localCodeId;
        $attrs['user_id'] = QrCode::find($localCodeId)?->user_id;

        if ($commit && $reference !== '') {
            QrEventRegistration::updateOrCreate(['reference' => $reference], $attrs);
        }
    }

    /** @param array<string,mixed> $row */
    private function importScanEvent(array $row, bool $commit): void
    {
        $platformCodeId = (int) ($row['platform_qr_code_id'] ?? 0);
        $localCodeId = $this->codeMap[$platformCodeId] ?? null;
        if (! $localCodeId) {
            return;
        }

        $attrs = collect($row)->except(['platform_id', 'platform_qr_code_id', 'id', 'qr_code_id'])->all();
        $attrs['qr_code_id'] = $localCodeId;

        if ($commit) {
            QrScanEvent::updateOrCreate(
                ['qr_code_id' => $localCodeId, 'created_at' => $attrs['created_at'] ?? now()],
                $attrs,
            );
        }
    }

    /** @param array<string,mixed> $row */
    private function importTransaction(array $row, bool $commit): void
    {
        $user = $this->resolveUser($row);
        if (! $user) {
            return;
        }

        $wallet = QrWallet::firstOrCreate(['user_id' => $user->id]);
        $reference = (string) ($row['reference'] ?? '');
        $attrs = collect($row)->except(['platform_id', 'owner_public_id', 'platform_qr_code_id', 'id', 'user_id', 'qr_wallet_id', 'qr_code_id'])->all();
        $attrs['user_id'] = $user->id;
        $attrs['qr_wallet_id'] = $wallet->id;

        $platformCodeId = (int) ($row['platform_qr_code_id'] ?? 0);
        if ($platformCodeId && isset($this->codeMap[$platformCodeId])) {
            $attrs['qr_code_id'] = $this->codeMap[$platformCodeId];
        }

        if ($commit && $reference !== '') {
            QrTransaction::updateOrCreate(['reference' => $reference], $attrs);
        }
    }

    private function copyCodeAssets(QrCode $code): void
    {
        $sourceRoot = $this->option('storage-source');
        if (! is_string($sourceRoot) || $sourceRoot === '' || ! is_dir($sourceRoot)) {
            return;
        }

        $paths = array_filter([
            $code->png_path,
            $code->svg_path,
        ]);

        $content = $code->content();
        foreach (['logo_path', 'cover_path'] as $key) {
            if (! empty($content[$key])) {
                $paths[] = $content[$key];
            }
        }

        foreach (array_unique($paths) as $relativePath) {
            $this->copyStorageFile($sourceRoot, (string) $relativePath);
        }
    }

    private function copyStorageFile(string $sourceRoot, string $relativePath): void
    {
        if ($relativePath === '') {
            return;
        }

        $sourceFile = rtrim($sourceRoot, '/').'/'.$relativePath;
        if (! is_file($sourceFile)) {
            $this->warn("Missing file on platform storage: {$sourceFile}");

            return;
        }

        if (Storage::disk('qr')->exists($relativePath)) {
            return;
        }

        $directory = dirname($relativePath);
        if ($directory !== '.' && $directory !== '') {
            Storage::disk('qr')->makeDirectory($directory);
        }

        Storage::disk('qr')->put($relativePath, (string) file_get_contents($sourceFile));
    }
}