<?php
defined( 'ABSPATH' ) || exit;

/**
 * Maps WooCommerce orders and refunds to the PeppolKit order format (the
 * Shopify REST order shape the PeppolKit API accepts). WooCommerce stores
 * line totals excluding tax, so orders are sent with taxes_included = false.
 */
class PeppolKit_Mapper {
	const VAT_META = '_billing_vat_number';

	private static function money( $amount ) {
		return number_format( (float) $amount, 2, '.', '' );
	}

	/** Tax lines of an order item: one per tax rate, rate as a fraction. */
	private static function tax_lines( $item ) {
		$out   = array();
		$taxes = $item->get_taxes();
		foreach ( (array) ( $taxes['total'] ?? array() ) as $rate_id => $amount ) {
			if ( '' === $amount || null === $amount ) {
				continue;
			}
			$out[] = array(
				'title' => WC_Tax::get_rate_label( $rate_id ),
				'rate'  => round( (float) WC_Tax::get_rate_percent_value( $rate_id ) / 100, 4 ),
				'price' => self::money( $amount ),
			);
		}
		return $out;
	}

	private static function address( $order, $type ) {
		$get = function ( $field ) use ( $order, $type ) {
			$fn = "get_{$type}_{$field}";
			return method_exists( $order, $fn ) ? (string) $order->$fn() : '';
		};
		$country = strtoupper( $get( 'country' ) );
		if ( '' === $country ) {
			return null;
		}
		return array(
			'name'         => trim( $get( 'first_name' ) . ' ' . $get( 'last_name' ) ),
			'company'      => $get( 'company' ),
			'address1'     => $get( 'address_1' ),
			'address2'     => $get( 'address_2' ),
			'city'         => $get( 'city' ),
			'zip'          => $get( 'postcode' ),
			'country_code' => $country,
		);
	}

	/** @param WC_Order $order */
	public static function order( $order ) {
		$lines = array();
		foreach ( $order->get_items( array( 'line_item', 'fee' ) ) as $item_id => $item ) {
			$is_fee = $item->is_type( 'fee' );
			$qty    = $is_fee ? 1 : max( 1, (int) $item->get_quantity() );
			$total  = (float) $item->get_total();
			// Unit price before discounts (excl. tax); the discount makes the line add up to the exact total.
			$before = $is_fee ? $total : (float) $item->get_subtotal();
			$unit   = round( $before / $qty, 2 );
			$disc   = round( $unit * $qty - $total, 2 );
			$product = $is_fee ? null : $item->get_product();
			$lines[] = array(
				'id'                   => (int) $item_id,
				'title'                => $item->get_name(),
				'sku'                  => $product ? $product->get_sku() : null,
				'quantity'             => $qty,
				'price'                => self::money( $unit ),
				'requires_shipping'    => $product ? $product->needs_shipping() : false,
				'taxable'              => 'none' !== ( $is_fee ? $item->get_tax_status() : ( $product ? $product->get_tax_status() : 'taxable' ) ),
				'tax_lines'            => self::tax_lines( $item ),
				'discount_allocations' => abs( $disc ) >= 0.01 ? array( array( 'amount' => self::money( $disc ) ) ) : array(),
			);
		}

		$shipping = array();
		foreach ( $order->get_items( 'shipping' ) as $item ) {
			$shipping[] = array(
				'title'     => $item->get_name(),
				'price'     => self::money( $item->get_total() ),
				'tax_lines' => self::tax_lines( $item ),
			);
		}

		$vat     = (string) $order->get_meta( self::VAT_META );
		$created = $order->get_date_created();
		$paid    = $order->get_date_paid();

		return array(
			'id'               => (int) $order->get_id(),
			'name'             => '#' . $order->get_order_number(),
			'currency'         => $order->get_currency(),
			'taxes_included'   => false,
			'created_at'       => $created ? $created->format( DATE_ATOM ) : gmdate( DATE_ATOM ),
			'processed_at'     => $paid ? $paid->format( DATE_ATOM ) : null,
			'email'            => $order->get_billing_email(),
			'financial_status' => 'paid',
			'billing_address'  => self::address( $order, 'billing' ),
			'shipping_address' => self::address( $order, 'shipping' ),
			'line_items'       => $lines,
			'shipping_lines'   => $shipping,
			'note_attributes'  => '' !== $vat ? array( array( 'name' => 'VAT number', 'value' => $vat ) ) : array(),
			'total_price'      => self::money( $order->get_total() ),
			'total_tax'        => self::money( $order->get_total_tax() ),
		);
	}

	/** @param WC_Order_Refund $refund */
	public static function refund( $refund ) {
		$items = array();
		foreach ( $refund->get_items() as $item ) {
			$original = (int) $item->get_meta( '_refunded_item_id' );
			$qty      = abs( (int) $item->get_quantity() );
			if ( $original && $qty > 0 ) {
				$items[] = array( 'line_item_id' => $original, 'quantity' => $qty );
			}
		}
		$created = $refund->get_date_created();
		return array(
			'id'                => (int) $refund->get_id(),
			'order_id'          => (int) $refund->get_parent_id(),
			'created_at'        => $created ? $created->format( DATE_ATOM ) : gmdate( DATE_ATOM ),
			'refund_line_items' => $items,
			'transactions'      => array(
				array(
					'kind'   => 'refund',
					'status' => 'success',
					'amount' => self::money( abs( (float) $refund->get_amount() ) ),
				),
			),
		);
	}
}