Lines and Taxes

// Simple product with VAT
$invoice->line(
    description: 'Laptop Computer',
    quantity: 2,
    price: 899.99,
    vat: 21
);

// Service with quantity = 1 (default)
$invoice->line(
    description: 'Web Development',
    price: 1500,
    vat: 21
);

public function line(
    string         $description,
    float          $price,
    float          $quantity = 1,
    ?float         $vat = null,
    ?float         $irpf = null,
    ?float         $igic = null,
    ?float         $surcharge = null,
    ?float         $ie = null,
    bool           $ieWithheld = false,
    ?float         $discount = null,
    ?string        $articleCode = null,
    ?string        $detailedDescription = null,
    ?UnitOfMeasure $unit = null,
): self

// Standard rate (21%)
$invoice->line('Software License', price: 100, vat: 21);

// Reduced rate (10%)
$invoice->line('Book', price: 20, vat: 10);

// Super-reduced rate (4%)
$invoice->line('Essential Food', price: 15, vat: 4);

// Consulting with VAT and IRPF
$invoice->line(
    description: 'Legal Consulting',
    price: 2000,
    vat: 21,      // 21% VAT charged
    irpf: 15      // 15% IRPF withheld
);

// Result:
// Base: 2000.00 €
// VAT (21%): +420.00 €
// IRPF (15%): -300.00 €
// Total: 2120.00 €

$invoice->line('Product shipped to Canary Islands', price: 100, igic: 7);

$invoice->line(
    description: 'Retail Product',
    price: 100,
    vat: 21,
    surcharge: 5.2  // 5.2% surcharge for 21% VAT rate
);

// Excise tax charged (default)
$invoice->line('Alcohol', price: 50, vat: 21, ie: 10);

// Excise tax withheld (less common)
$invoice->line('Tobacco', price: 50, vat: 21, ie: 10, ieWithheld: true);

$invoice->line(
    description: 'Product with discount',
    quantity: 10,
    price: 100,
    discount: 20,  // 20% discount
    vat: 21
);

// Calculation:
// Subtotal: 10 × 100 = 1000.00
// Discount: -20% = -200.00
// Base: 800.00
// VAT (21%): +168.00
// Line total: 968.00

$invoice->line(
    description: 'Laptop Model X',
    price: 899,
    articleCode: 'SKU-12345-B',
    vat: 21
);

use PhpFacturae\Enums\UnitOfMeasure;

// Energy billing
$invoice->line(
    description: 'Electricity consumption',
    quantity: 150.5,
    price: 0.15,
    unit: UnitOfMeasure::KWh,
    vat: 21
);

// Other common units
$invoice->line('Fabric', quantity: 50, price: 12, unit: UnitOfMeasure::Meters, vat: 21);
$invoice->line('Flour', quantity: 25, price: 2.5, unit: UnitOfMeasure::Kilograms, vat: 10);
$invoice->line('Consultation Hours', quantity: 8, price: 85, unit: UnitOfMeasure::Hours, vat: 21);

$invoice->line(
    description: 'Custom Software Development',
    price: 5000,
    vat: 21,
    detailedDescription: 'Development of custom CRM module including:\n'
        . '- User management system\n'
        . '- Advanced reporting dashboard\n'
        . '- API integration with external services\n'
        . '- 3 months of support and maintenance'
);

$invoice->exemptLine(
    description: 'Professional training course',
    price: 2000,
    quantity: 1,
    reason: 'Exempt per Article 20 LIVA'
);

use PhpFacturae\Entities\TaxBreakdown;
use PhpFacturae\Enums\Tax;

$invoice->customLine(
    description: 'Complex service',
    price: 1000,
    taxes: [
        new TaxBreakdown(Tax::IVA, rate: 21),
        new TaxBreakdown(Tax::IRPF, rate: 15),
    ]
);

Tax::IVA      // Value Added Tax
Tax::IPSI     // Canary Islands Production Tax
Tax::IGIC     // Canary Islands General Indirect Tax
Tax::IRPF     // Personal Income Tax withholding
Tax::IRNR     // Non-Resident Income Tax
Tax::IE       // Special Tax (Excise)
Tax::RA       // Agricultural equivalence surcharge
Tax::ITPAJD   // Property Transfer Tax
Tax::REIVA    // Equivalence surcharge (VAT)
Tax::REIGIC   // Equivalence surcharge (IGIC)
Tax::REIPSI   // Equivalence surcharge (IPSI)
// ... and 18 more specialized taxes

new TaxBreakdown(
    type: Tax,           // Tax type from enum
    rate: float,         // Percentage rate
    isWithholding: ?bool = null,  // null = use default for tax type
    surchargeRate: ?float = null  // Only for IVA with surcharge
)

use PhpFacturae\Entities\TaxBreakdown;
use PhpFacturae\Enums\Tax;

$invoice->customLine(
    description: 'Professional service with multiple taxes',
    price: 1000,
    taxes: [
        new TaxBreakdown(Tax::IVA, 21),        // +210 charged
        new TaxBreakdown(Tax::IRPF, 15),       // -150 withheld
        new TaxBreakdown(Tax::IE, 5),          // +50 charged
    ]
);

// Calculation:
// Base: 1000.00
// IVA (21%): +210.00
// IRPF (15%): -150.00
// IE (5%): +50.00
// Total: 1110.00

$invoice->line('Standard rate product', price: 100, vat: 21)
        ->line('Reduced rate product', price: 100, vat: 10)
        ->line('Super-reduced product', price: 100, vat: 4)
        ->line('Professional service', price: 500, vat: 21, irpf: 15)
        ->exemptLine('Exempt service', price: 200, reason: 'Article 20 LIVA');

// Invoice will group taxes correctly in the XML output

use PhpFacturae\Enums\SpecialTaxableEvent;

$invoice->customLine(
    description: 'Intra-community supply',
    price: 5000,
    taxes: [],
    specialTaxableEvent: SpecialTaxableEvent::Exempt,
    specialTaxableEventReason: 'Intra-EU supply - Article 25 LIVA'
);

$invoice->line('Software development', price: 3000, vat: 21, irpf: 15)
        ->line('Server hosting (monthly)', price: 150, vat: 21)
        ->line('Domain registration', price: 25, vat: 21);

$invoice->line('Product A', quantity: 5, price: 20, vat: 21, surcharge: 5.2)
        ->line('Product B', quantity: 3, price: 50, vat: 21, surcharge: 5.2)
        ->line('Product C', quantity: 10, price: 8, vat: 10, surcharge: 1.4);

$invoice->line('Consulting services', price: 2000, vat: 21, irpf: 15)
        ->exemptLine('Educational training', price: 1500, 
            reason: 'Exempt per Article 20.1.9 LIVA')
        ->line('Technical materials', quantity: 3, price: 45.50, vat: 21);