<?php
/**
 * Rate resolution cascade and purchase sequence rules.
 *
 * @package PPL_AFW
 */

namespace PPL_AFW\Commissions;

use PPL_AFW\Core\Settings;

defined( 'ABSPATH' ) || exit;

// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- This plugin stores affiliate data in its own custom tables, which the WordPress data APIs cannot read or write, so direct queries are required. Every query is assembled from string literals and executed through $wpdb->prepare(), with %i for table names and %s/%d/%f for values, so nothing is ever interpolated into SQL.

/**
 * Resolves the commission rate for an order.
 *
 * A per affiliate override wins, otherwise the store wide default applies.
 * The ppl_afw_resolved_rate filter can insert more specific rates.
 */
class Rate_Resolver {

	/**
	 * Settings.
	 *
	 * @var Settings
	 */
	private $settings;

	/**
	 * Constructor.
	 *
	 * @param Settings $settings Settings service.
	 */
	public function __construct( Settings $settings ) {
		$this->settings = $settings;
	}

	/**
	 * Resolves the rate for an affiliate, product, and purchase number.
	 *
	 * @since 1.0.0
	 * @param object                      $affiliate       Affiliate row.
	 * @param int                         $product_id      Product id, 0 for an order level rate (shipping).
	 * @param int                         $purchase_number 1-based number of this customer's paid purchases, this one included.
	 * @param \WC_Order_Item_Product|null $item            The line item the rate is for, when there is one.
	 * @return array{type: string, value: float, source: string}
	 */
	public function resolve( $affiliate, $product_id, $purchase_number = 1, $item = null ) {
		$rate = null;

		// A per affiliate rate override beats the store wide default.
		if ( '' !== $affiliate->rate_type && $affiliate->rate_value > 0 ) {
			$rate = array(
				'type'   => $affiliate->rate_type,
				'value'  => (float) $affiliate->rate_value,
				'source' => 'affiliate',
			);
		}

		if ( ! $rate ) {
			$rate = array(
				'type'   => (string) $this->settings->get( 'rate_type' ),
				'value'  => (float) $this->settings->get( 'rate_value' ),
				'source' => 'global',
			);
		}

		/**
		 * Filters the resolved commission rate.
		 *
		 * Runs once per line item, and once with product id 0 for shipping.
		 *
		 * @since 1.0.0
		 * @since 1.3.0 The line item is passed.
		 * @param array                       $rate            type, value, source.
		 * @param object                      $affiliate       Affiliate row.
		 * @param int                         $product_id      Product id.
		 * @param int                         $purchase_number Customer purchase number.
		 * @param \WC_Order_Item_Product|null $item            Line item, or null.
		 */
		return apply_filters( 'ppl_afw_resolved_rate', $rate, $affiliate, $product_id, $purchase_number, $item );
	}

	/**
	 * Computes the commission amount from a base and a rate.
	 *
	 * @since 1.0.0
	 * @param float $base Base amount.
	 * @param array $rate type, value.
	 * @return float
	 */
	public function calculate( $base, array $rate ) {
		if ( 'flat' === $rate['type'] ) {
			return round( (float) $rate['value'], 4 );
		}
		return round( $base * (float) $rate['value'] / 100, 4 );
	}

}