<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;

class Inventory extends Model
{
    /** @use HasFactory<\Database\Factories\InventoryFactory> */
    use HasFactory;
    use \Spatie\Activitylog\Traits\LogsActivity;

    protected $fillable = [
        'warehouse_id',
        'product_id',
        'quantity',
        'safety_stock',
        'location',
        // 批號追溯欄位
        'batch_number',
        'box_number',
        'origin_country',
        'arrival_date',
        'expiry_date',
        'source_purchase_order_id',
        'quality_status',
        'quality_remark',
    ];

    protected $casts = [
        'arrival_date' => 'date:Y-m-d',
        'expiry_date' => 'date:Y-m-d',
    ];

    /**
     * Transient property to store the reason for the activity log (e.g., "Replenishment #123").
     * This is not stored in the database column but used for logging context.
     * @var string|null
     */
    public $activityLogReason;

    public function getActivitylogOptions(): \Spatie\Activitylog\LogOptions
    {
        return \Spatie\Activitylog\LogOptions::defaults()
            ->logAll()
            ->logOnlyDirty()
            ->dontSubmitEmptyLogs();
    }

    public function tapActivity(\Spatie\Activitylog\Contracts\Activity $activity, string $eventName)
    {
        $properties = $activity->properties;
        $attributes = $properties['attributes'] ?? [];
        $snapshot = $properties['snapshot'] ?? [];

        // Always snapshot names for context, even if IDs didn't change
        // $this refers to the Inventory model instance
        $snapshot['warehouse_name'] = $this->warehouse ? $this->warehouse->name : ($snapshot['warehouse_name'] ?? null);
        $snapshot['product_name'] = $this->product ? $this->product->name : ($snapshot['product_name'] ?? null);

        // Capture the reason if set
        if ($this->activityLogReason) {
            $attributes['_reason'] = $this->activityLogReason;
        }

        $properties['attributes'] = $attributes;
        $properties['snapshot'] = $snapshot;
        $activity->properties = $properties;
    }

    public function warehouse(): \Illuminate\Database\Eloquent\Relations\BelongsTo
    {
        return $this->belongsTo(Warehouse::class);
    }

    public function product(): \Illuminate\Database\Eloquent\Relations\BelongsTo
    {
        return $this->belongsTo(Product::class);
    }

    public function transactions(): \Illuminate\Database\Eloquent\Relations\HasMany
    {
        return $this->hasMany(InventoryTransaction::class);
    }

    public function lastOutgoingTransaction()
    {
        return $this->hasOne(InventoryTransaction::class)->ofMany([
            'actual_time' => 'max',
            'id' => 'max',
        ], function ($query) {
            $query->where('quantity', '<', 0);
        });
    }

    public function lastIncomingTransaction()
    {
        return $this->hasOne(InventoryTransaction::class)->ofMany([
            'actual_time' => 'max',
            'id' => 'max',
        ], function ($query) {
            $query->where('quantity', '>', 0);
        });
    }

    /**
     * 來源採購單
     */
    public function sourcePurchaseOrder(): \Illuminate\Database\Eloquent\Relations\BelongsTo
    {
        return $this->belongsTo(PurchaseOrder::class, 'source_purchase_order_id');
    }

    /**
     * 產生批號
     * 格式：{商品代號}-{來源國家}-{入庫日期}-{批次流水號}
     */
    public static function generateBatchNumber(string $productCode, string $originCountry, string $arrivalDate): string
    {
        $dateFormatted = date('Ymd', strtotime($arrivalDate));
        $prefix = "{$productCode}-{$originCountry}-{$dateFormatted}-";

        $lastBatch = static::where('batch_number', 'like', "{$prefix}%")
            ->orderByDesc('batch_number')
            ->first();

        if ($lastBatch) {
            $lastNumber = (int) substr($lastBatch->batch_number, -2);
            $nextNumber = str_pad($lastNumber + 1, 2, '0', STR_PAD_LEFT);
        } else {
            $nextNumber = '01';
        }

        return $prefix . $nextNumber;
    }
}