Inventory Management

class Producto extends ModelClass
{
    use TaxRelationTrait;
    
    public $idproducto;        // Primary key
    public $referencia;        // Product reference/SKU
    public $descripcion;       // Description
    public $precio;            // Base price (without tax)
    public $stockfis;          // Total physical stock
    public $codfamilia;        // Product family code
    public $codfabricante;     // Manufacturer code
    
    // Stock control flags
    public $nostock;           // Don't control stock
    public $ventasinstock;     // Allow sales without stock
    public $secompra;          // Can be purchased
    public $sevende;           // Can be sold
    
    // Status
    public $bloqueado;         // Blocked/obsolete
    public $publico;           // Public (sync to online store)
    
    // Accounting
    public $codsubcuentacom;   // Purchase account
    public $codsubcuentaven;   // Sales account
    public $codsubcuentairpfcom; // IRPF purchase account
    
    // Dates
    public $fechaalta;         // Creation date
    public $actualizado;       // Last update
    
    // Tax
    public $codimpuesto;       // Tax code
    public $excepcioniva;      // VAT exception
}

public function getVariants(): array
{
    // Returns all variants for this product
    // Each variant has its own:
    // - Reference (SKU)
    // - Price
    // - Stock level
    // - Attributes
}

public function getImages(bool $imgVariant = true): array
{
    // Returns product images
    // Can filter to exclude variant-specific images
}

public function priceWithTax(): float
{
    return $this->precio * (100 + $this->getTax()->iva) / 100;
}

public function setPriceWithTax(float $price): bool
{
    // Sets base price from tax-inclusive price
}

public $nostock = true;

public $ventasinstock = true;

if ($this->bloqueado) {
    $this->publico = false;
    $this->sevende = false;
    $this->secompra = false;
}

class Almacen extends ModelClass
{
    use CompanyRelationTrait;
    
    public $codalmacen;        // Warehouse code (1-4 chars)
    public $nombre;            // Name
    public $idempresa;         // Company ID
    
    // Address
    public $direccion;         // Address
    public $ciudad;            // City
    public $provincia;         // Province/state
    public $codpostal;         // Postal code
    public $apartado;          // P.O. Box
    public $codpais;           // Country code
    
    // Contact
    public $telefono;          // Phone
    
    // Status
    public $activo;            // Active/inactive
}

public function isDefault(): bool
{
    return $this->codalmacen === Tools::settings('default', 'codalmacen');
}

class Stock extends ModelClass
{
    use ProductRelationTrait;
    
    public $idstock;           // Primary key
    public $idproducto;        // Product ID
    public $referencia;        // Product reference
    public $codalmacen;        // Warehouse code
    
    // Quantities
    public $cantidad;          // Physical quantity
    public $reservada;         // Reserved quantity
    public $disponible;        // Available (cantidad - reservada)
    public $pterecibir;        // Pending receipt from suppliers
    
    // Stock levels
    public $stockmin;          // Minimum stock level
    public $stockmax;          // Maximum stock level
    
    // Location
    public $ubicacion;         // Bin/location code
}

public function test(): bool
{
    // Automatically calculates available stock
    $this->disponible = max([0, $this->cantidad - $this->reservada]);
}

public function transferTo(string $toWarehouse, float $qty): bool
{
    // Transfers stock between warehouses
    // Updates both source and destination
    $destination = new Stock();
    if ($destination->loadWhere(['codalmacen' => $toWarehouse, 
                                  'referencia' => $this->referencia])) {
        $destination->cantidad += $qty;
    } else {
        // Create new stock record in destination
    }
    
    $this->cantidad -= $qty;
    return $destination->save() && $this->save();
}

public function totalFromProduct(int $idproducto, string $referencia = ''): float
{
    // Sums stock across all warehouses for a product
    // Optional: Filter by specific reference (variant)
}

protected function updateProductStock(): bool
{
    // Updates producto.stockfis with total from all warehouses
    // Updates variante.stockfis for specific reference
}

// In document lines (e.g., LineaAlbaranCliente)
$newLine->actualizastock = $this->getStatus()->actualizastock;

public $ubicacion;  // Bin/location within warehouse

public $codfamilia;  // Product family code

public function getFamilia(): ?Familia
{
    return $this->belongsTo(Familia::class, 'codfamilia');
}

public $codfabricante;  // Manufacturer code

public function getFabricante(): ?Fabricante
{
    return $this->belongsTo(Fabricante::class, 'codfabricante');
}

public function test(): bool
{
    // Reference validation (max 30 chars)
    // Description cannot be null
    // Stock cleared if nostock enabled
    // Blocked products cannot be public/sold/purchased
    // Tax validation with exceptions
    
    if ($this->nostock && $this->stockfis != 0) {
        // Clear all stock records
        DELETE FROM stocks WHERE idproducto = ...
    }
}

public function delete(): bool
{
    // Check if variants used in documents
    foreach ($this->getVariants() as $variant) {
        if ($variant->isInDocuments()) {
            Tools::log()->warning('cant-delete-variant-with-documents');
            return false;
        }
    }
    
    // Delete images first
    // Then delete product
}

protected function saveInsert(): bool
{
    // Check for duplicate reference
    $where = [new DataBaseWhere('referencia', $this->referencia)];
    if ($this->count($where) > 0) {
        Tools::log()->warning('duplicated-reference');
        return false;
    }
}

if (empty($this->referencia)) {
    // Auto-generate from Variante model
    $variant = new Variante();
    $this->referencia = (string)$variant->newCode('referencia');
}

public function test(): bool
{
    $this->actualizado = Tools::dateTime();
    // ...
}

public function updateInfo(): void
{
    // Updates product price and reference from variants
    // Uses main variant or first variant
}