<?php

namespace App\Services;

use App\Models\Tenants\Stock;
use Illuminate\Contracts\Pagination\LengthAwarePaginator;

class StockService extends Service
{
    /**
     * 재고 목록 조회
     */
    public function index(array $params): LengthAwarePaginator
    {
        $tenantId = $this->tenantId();

        $query = Stock::query()
            ->where('tenant_id', $tenantId)
            ->with('item');

        // 검색어 필터
        if (! empty($params['search'])) {
            $search = $params['search'];
            $query->where(function ($q) use ($search) {
                $q->where('item_code', 'like', "%{$search}%")
                    ->orWhere('item_name', 'like', "%{$search}%");
            });
        }

        // 품목유형 필터
        if (! empty($params['item_type'])) {
            $query->where('item_type', $params['item_type']);
        }

        // 재고 상태 필터
        if (! empty($params['status'])) {
            $query->where('status', $params['status']);
        }

        // 위치 필터
        if (! empty($params['location'])) {
            $query->where('location', 'like', "%{$params['location']}%");
        }

        // 정렬
        $sortBy = $params['sort_by'] ?? 'item_code';
        $sortDir = $params['sort_dir'] ?? 'asc';
        $query->orderBy($sortBy, $sortDir);

        // 페이지네이션
        $perPage = $params['per_page'] ?? 20;

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

    /**
     * 재고 통계 조회
     */
    public function stats(): array
    {
        $tenantId = $this->tenantId();

        $totalItems = Stock::where('tenant_id', $tenantId)->count();

        $normalCount = Stock::where('tenant_id', $tenantId)
            ->where('status', 'normal')
            ->count();

        $lowCount = Stock::where('tenant_id', $tenantId)
            ->where('status', 'low')
            ->count();

        $outCount = Stock::where('tenant_id', $tenantId)
            ->where('status', 'out')
            ->count();

        return [
            'total_items' => $totalItems,
            'normal_count' => $normalCount,
            'low_count' => $lowCount,
            'out_count' => $outCount,
        ];
    }

    /**
     * 재고 상세 조회 (LOT 포함)
     */
    public function show(int $id): Stock
    {
        $tenantId = $this->tenantId();

        return Stock::query()
            ->where('tenant_id', $tenantId)
            ->with(['item', 'lots' => function ($query) {
                $query->orderBy('fifo_order');
            }])
            ->findOrFail($id);
    }

    /**
     * 품목코드로 재고 조회
     */
    public function findByItemCode(string $itemCode): ?Stock
    {
        $tenantId = $this->tenantId();

        return Stock::query()
            ->where('tenant_id', $tenantId)
            ->where('item_code', $itemCode)
            ->first();
    }

    /**
     * 품목유형별 통계
     */
    public function statsByItemType(): array
    {
        $tenantId = $this->tenantId();

        $stats = Stock::where('tenant_id', $tenantId)
            ->selectRaw('item_type, COUNT(*) as count, SUM(stock_qty) as total_qty')
            ->groupBy('item_type')
            ->get()
            ->keyBy('item_type');

        $result = [];
        foreach (Stock::ITEM_TYPES as $key => $label) {
            $data = $stats->get($key);
            $result[$key] = [
                'label' => $label,
                'count' => $data?->count ?? 0,
                'total_qty' => $data?->total_qty ?? 0,
            ];
        }

        return $result;
    }
}