<?php

declare(strict_types=1);

namespace Modules\Helpdesk\Console;

use Illuminate\Console\Command;
use Illuminate\Database\ConnectionInterface;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;
use Modules\Helpdesk\Models\LegacyCategory;
use Modules\Helpdesk\Models\LegacyComment;
use Modules\Helpdesk\Models\LegacyTicket;
use Throwable;

final class ImportLegacyHelpdeskCommand extends Command
{
    protected $signature = 'helpdesk:import-legacy {--connection= : Laravel database connection containing the old tickets tables} {--fresh : Clear previously imported legacy records first}';
    protected $description = 'Import the old Helpdesk tickets and categories into the read-only Legacy System';

    public function handle(): int
    {
        $connectionName = (string) ($this->option('connection') ?: config('helpdesk.legacy_connection', config('database.default')));
        $source = DB::connection($connectionName);
        $schema = Schema::connection($connectionName);

        foreach (['tickets', 'tickets_categories'] as $table) {
            if (! $schema->hasTable($table)) {
                $this->error("Source table {$table} was not found on connection [{$connectionName}].");
                return self::FAILURE;
            }
        }

        if ($this->option('fresh')) {
            LegacyComment::query()->delete();
            LegacyTicket::query()->delete();
            LegacyCategory::query()->delete();
        }

        $this->importCategories($source);
        $this->importTickets($source, $schema);
        $this->importComments($source, $schema);
        $this->refreshCategoryCounts();

        $this->info(sprintf('Legacy import complete: %d tickets, %d categories, %d comments.', LegacyTicket::count(), LegacyCategory::count(), LegacyComment::count()));
        return self::SUCCESS;
    }

    private function importCategories(ConnectionInterface $source): void
    {
        $source->table('tickets_categories')->orderBy('id')->chunk(500, function ($rows): void {
            foreach ($rows as $row) {
                LegacyCategory::updateOrCreate(['legacy_id' => $row->id], ['name' => (string) $row->name, 'color' => $row->color ?? null]);
            }
        });
    }

    private function importTickets(ConnectionInterface $source, $schema): void
    {
        $columns = collect($schema->getColumnListing('tickets'));
        $lookups = [
            'category' => $this->lookup($source, $schema, 'tickets_categories'),
            'status' => $this->lookup($source, $schema, 'tickets_statuses'),
            'priority' => $this->lookup($source, $schema, 'tickets_priorities'),
            'project' => $this->lookup($source, $schema, 'projects'),
            'user' => $this->lookup($source, $schema, 'users'),
        ];

        $source->table('tickets')->orderBy('id')->chunk(250, function ($rows) use ($columns, $lookups): void {
            foreach ($rows as $row) {
                $data = (array) $row;
                LegacyTicket::updateOrCreate(['legacy_id' => $row->id], [
                    'reference' => $data['reference'] ?? null,
                    'subject' => (string) ($data['subject'] ?? 'Legacy ticket #'.$row->id),
                    'content' => $data['content'] ?? null,
                    'html_content' => $data['htmlcontent'] ?? null,
                    'legacy_category_id' => $data['category_id'] ?? null,
                    'category_name' => $lookups['category'][$data['category_id'] ?? 0] ?? null,
                    'status_name' => $lookups['status'][$data['status_id'] ?? 0] ?? null,
                    'priority_name' => $lookups['priority'][$data['priority_id'] ?? 0] ?? null,
                    'requester_name' => $lookups['user'][$data['user_id'] ?? 0] ?? null,
                    'agent_name' => $lookups['user'][$data['agent_id'] ?? 0] ?? null,
                    'project_name' => $lookups['project'][$data['project_id'] ?? 0] ?? null,
                    'legacy_created_at' => $data['created_at'] ?? null,
                    'legacy_updated_at' => $data['updated_at'] ?? null,
                    'completed_at' => $data['completed_at'] ?? null,
                    'archived_at' => $data['archived_at'] ?? null,
                    'legacy_data' => $data,
                ]);
            }
        });
    }

    private function importComments(ConnectionInterface $source, $schema): void
    {
        if (! $schema->hasTable('tickets_comments')) return;
        $users = $this->lookup($source, $schema, 'users');
        $source->table('tickets_comments')->orderBy('id')->chunk(500, function ($rows) use ($users): void {
            foreach ($rows as $row) {
                $data = (array) $row;
                LegacyComment::updateOrCreate(['legacy_id' => $row->id], [
                    'legacy_ticket_id' => $data['ticket_id'],
                    'author_name' => $users[$data['user_id'] ?? 0] ?? null,
                    'content' => $data['content'] ?? null,
                    'html_content' => $data['htmlcontent'] ?? null,
                    'legacy_created_at' => $data['created_at'] ?? null,
                    'legacy_updated_at' => $data['updated_at'] ?? null,
                ]);
            }
        });
    }

    private function lookup(ConnectionInterface $source, $schema, string $table): array
    {
        if (! $schema->hasTable($table)) return [];
        $columns = $schema->getColumnListing($table);
        $nameColumn = in_array('name', $columns, true) ? 'name' : (in_array('username', $columns, true) ? 'username' : null);
        if ($nameColumn === null) return [];
        try { return $source->table($table)->pluck($nameColumn, 'id')->map(fn ($v) => (string) $v)->all(); } catch (Throwable) { return []; }
    }

    private function refreshCategoryCounts(): void
    {
        LegacyCategory::query()->each(function (LegacyCategory $category): void {
            $category->update(['ticket_count' => LegacyTicket::query()->where('legacy_category_id', $category->legacy_id)->count()]);
        });
    }
}