<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Relations\BelongsTo;

class PurchaseOrderItem extends BaseModel
{
    protected $table = 'purchase_order_items';

    protected $fillable = ['purchase_order_id', 'supply_id', 'description', 'quantity', 'received_qty', 'unit_cost'];

    public $timestamps = true;

    protected $casts = [
        'purchase_order_id' => 'integer',
        'supply_id' => 'integer',
        'quantity' => 'integer',
        'received_qty' => 'integer',
        'unit_cost' => 'decimal:2',   // adjust scale to match DB (e.g., decimal:4)
        'created_at' => 'datetime',
        'updated_at' => 'datetime',
    ];

    public function getFillable(): array
    {
        return $this->fillable;
    }

    /* ============================================================
     * Relationships (optional but recommended)
     * ============================================================
     */

    public function purchaseOrder(): BelongsTo
    {
        return $this->belongsTo(PurchaseOrder::class, 'purchase_order_id');
    }

    public function supply(): BelongsTo
    {
        return $this->belongsTo(Supply::class, 'supply_id');
    }

    /* ============================================================
     * Accessors (handy for totals / UI)
     * ============================================================
     */

    // total ordered cost
    public function getLineTotalAttribute(): float
    {
        $qty = (int) ($this->quantity ?? 0);
        $cost = (float) ($this->unit_cost ?? 0);

        return $qty * $cost;
    }

    // total received cost
    public function getReceivedLineTotalAttribute(): float
    {
        $qty = (int) ($this->received_qty ?? 0);
        $cost = (float) ($this->unit_cost ?? 0);

        return $qty * $cost;
    }

    /* ============================================================
     * Validation rules (use in FormRequest or controller)
     * ============================================================
     */

    public static function rules(bool $updating = false): array
    {
        // if updating, you might allow partial updates (sometimes)
        // keep strict by default to match legacy behavior
        return [
            'purchase_order_id' => [$updating ? 'sometimes' : 'required', 'integer', 'min:1', 'exists:purchase_orders,id'],
            'supply_id' => [$updating ? 'sometimes' : 'required', 'integer', 'min:1', 'exists:supplies,id'],
            'description' => ['nullable', 'string', 'max:1000'],
            'quantity' => [$updating ? 'sometimes' : 'required', 'integer', 'min:1'],
            'received_qty' => ['nullable', 'integer', 'min:0', 'lte:quantity'],
            'unit_cost' => [$updating ? 'sometimes' : 'required', 'numeric', 'min:0'],
        ];
    }
}