<?php

namespace App\Services;

use App\Models\StoreItem;
use App\Models\StoreItemInterest;
use App\Models\StoreItemVariation;
use Illuminate\Database\Eloquent\Collection;
use Illuminate\Support\Arr;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;

class StoreItemService
{
    public function getAll(): Collection
    {
        return StoreItem::with(['category', 'media', 'variations'])
            ->withCount('interests')
            ->orderBy('name')
            ->get();
    }

    public function findById(int $id): ?StoreItem
    {
        return StoreItem::with(['category', 'media', 'variations'])->find($id);
    }

    public function create(array $data): StoreItem
    {
        return DB::transaction(function () use ($data) {
            $variations = $data['variations'] ?? [];
            $item = StoreItem::create(Arr::except($data, ['variations']));
            foreach ($variations as $variation) {
                $item->variations()->create($variation);
            }
            return $item->load(['category', 'media', 'variations']);
        });
    }

    public function update(int $id, array $data): ?StoreItem
    {
        return DB::transaction(function () use ($id, $data) {
            $model = StoreItem::findOrFail($id);
            $variations = array_key_exists('variations', $data) ? $data['variations'] : null;
            $model->update(Arr::except($data, ['variations']));
            if (!is_null($variations)) {
                $model->variations()->delete();
                foreach ($variations as $variation) {
                    $model->variations()->create($variation);
                }
            }
            return $model->fresh(['category', 'media', 'variations']);
        });
    }

    public function delete(int $id): bool
    {
        $model = StoreItem::find($id);
        if (!$model) return false;
        return $model->delete();
    }

    public function getAllPaginated(array $filters = [], int $perPage = 10): \Illuminate\Contracts\Pagination\LengthAwarePaginator
    {
        $query = StoreItem::with(['category', 'media', 'variations'])
            ->withCount('interests')
            ->orderBy('name');

        if (!empty($filters['search'])) {
            $search = $filters['search'];
            $query->where('name', 'ilike', "%{$search}%");
        }

        if (!empty($filters['status'])) {
            $query->where('status', $filters['status']);
        }

        if (!empty($filters['category_id'])) {
            $query->where('category_id', $filters['category_id']);
        }

        return $query->paginate($perPage);
    }

    public function toggleStatus(int $id): ?StoreItem
    {
        $model = StoreItem::find($id);
        if (!$model) return null;

        $model->status = $model->status->value === 'active'
            ? \App\Enums\StoreItemStatusEnum::INACTIVE
            : \App\Enums\StoreItemStatusEnum::ACTIVE;
        $model->save();

        return $model->fresh(['category', 'media', 'variations']);
    }

    public function getMyInterests(): Collection
    {
        $userId = Auth::id();
        return StoreItem::with(['category', 'media', 'variations'])
            ->withCount('interests')
            ->whereHas('interests', fn($q) => $q->where('user_id', $userId))
            ->orderBy('name')
            ->get();
    }

    public function toggleInterest(int $storeItemId): array
    {
        $userId = Auth::id();
        $existing = StoreItemInterest::where('user_id', $userId)
            ->where('store_item_id', $storeItemId)
            ->first();

        if ($existing) {
            $existing->delete();
            return ['interested' => false];
        }

        StoreItemInterest::create(['user_id' => $userId, 'store_item_id' => $storeItemId]);
        return ['interested' => true];
    }

    public function getInterestsByItem(int $storeItemId): array
    {
        return StoreItemInterest::with('user')
            ->where('store_item_id', $storeItemId)
            ->get()
            ->map(fn($interest) => [
                'id'    => $interest->user?->id,
                'name'  => $interest->user?->name,
                'email' => $interest->user?->email,
            ])
            ->values()
            ->toArray();
    }

    public function addVariation(int $storeItemId, array $data): StoreItemVariation
    {
        $item = StoreItem::findOrFail($storeItemId);
        return $item->variations()->create($data);
    }

    public function updateVariation(int $storeItemId, int $variationId, array $data): StoreItemVariation
    {
        $variation = StoreItemVariation::where('store_item_id', $storeItemId)
            ->findOrFail($variationId);
        $variation->update($data);
        return $variation->fresh();
    }

    public function deleteVariation(int $storeItemId, int $variationId): void
    {
        StoreItemVariation::where('store_item_id', $storeItemId)
            ->findOrFail($variationId)
            ->delete();
    }
}