<?php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Stock extends Model
{
    protected $table = 'stocks';

    protected $fillable = [
        'sku_code',
        'sku_name',
        'warehouse_id',
        'quantity',
        'locked_quantity',
        'defective_quantity',
        'warning_threshold',
    ];

    protected $casts = [
        'quantity' => 'integer',
        'locked_quantity' => 'integer',
        'defective_quantity' => 'integer',
        'warning_threshold' => 'integer',
    ];

    /**
     * 可用库存（总库存 - 占用库存）
     */
    public function getAvailableQuantityAttribute()
    {
        return $this->quantity - $this->locked_quantity;
    }

    /**
     * 关联仓库
     */
    public function warehouse()
    {
        return $this->belongsTo(Warehouse::class);
    }

    /**
     * 关联ERP商品
     */
    public function sku()
    {
        return $this->belongsTo(ErpSku::class, 'sku_code', 'sku_code');
    }

    /**
     * 获取该SKU在该仓库的库存流水
     */
    public function logs()
    {
        return $this->hasMany(StockLog::class, 'sku_code', 'sku_code')
                    ->where('warehouse_id', $this->warehouse_id);
    }
}