<?php

namespace App\Services;

use App\Models\Group;
use Illuminate\Database\Eloquent\Collection;

class GroupService
{
    public function getAll(): Collection
    {
        return Group::with('units')
            ->orderBy('name')
            ->get();
    }

    public function findById(int $id): ?Group
    {
        return Group::with('units')->find($id);
    }

    public function create(array $data): Group
    {
        $group = Group::create([
            'name'   => $data['name'],
            'status' => $data['status'] ?? 'ACTIVE',
        ]);

        if (!empty($data['unit_ids'])) {
            $group->units()->sync($data['unit_ids']);
        }

        return $group->load('units');
    }

    public function update(int $id, array $data): ?Group
    {
        $group = $this->findById($id);

        if (!$group) {
            return null;
        }

        $group->update(array_filter([
            'name'   => $data['name'] ?? null,
            'status' => $data['status'] ?? null,
        ], fn($v) => $v !== null));

        if (array_key_exists('unit_ids', $data)) {
            $group->units()->sync($data['unit_ids'] ?? []);
        }

        return $group->fresh('units');
    }

    public function delete(int $id): bool
    {
        $group = $this->findById($id);

        if (!$group) {
            return false;
        }

        $group->units()->detach();
        return $group->delete();
    }
}