<?php
/**
 * Where the value of one marketplace attribute comes from.
 *
 * @package Tidelist
 */

namespace Tidelist\Mapping;

/**
 * Attribute mapping rule (value object).
 */
final class AttributeRule {

	const WC_ATTRIBUTE = 'wc_attribute'; // A WooCommerce product attribute (global pa_* or custom).
	const FIELD        = 'field';        // A product field: brand, sku, weight, title.
	const FIXED        = 'fixed';        // The same value for every product.
	const ASK          = 'ask';          // Chosen per product.
	const SKIP         = 'skip';         // Never send this attribute.

	/**
	 * Product fields a rule can read.
	 */
	const FIELDS = array( 'brand', 'sku', 'weight', 'length', 'width', 'height', 'title' );

	/**
	 * Source type.
	 *
	 * @var string
	 */
	public $type = self::SKIP;

	/**
	 * WooCommerce attribute name (e.g. pa_color) or field name.
	 *
	 * @var string
	 */
	public $key = '';

	/**
	 * Fixed value (for FIXED).
	 *
	 * @var string
	 */
	public $fixed = '';

	/**
	 * Explicit value mapping: normalised shop value => marketplace value code. Wins over suggestions.
	 *
	 * @var array<string, string>
	 */
	public $values = array();

	/**
	 * Constructor.
	 *
	 * @param array $data Rule data (type, key, fixed, values).
	 */
	public function __construct( array $data = array() ) {
		$type = (string) ( $data['type'] ?? self::SKIP );
		if ( in_array( $type, array( self::WC_ATTRIBUTE, self::FIELD, self::FIXED, self::ASK, self::SKIP ), true ) ) {
			$this->type = $type;
		}
		$this->key   = (string) ( $data['key'] ?? '' );
		$this->fixed = (string) ( $data['fixed'] ?? '' );
		foreach ( (array) ( $data['values'] ?? array() ) as $shop => $remote ) {
			$shop = Normalizer::key( (string) $shop );
			if ( '' !== $shop && '' !== (string) $remote ) {
				$this->values[ $shop ] = (string) $remote;
			}
		}
	}

	/**
	 * Rule data for storing.
	 */
	public function to_array(): array {
		return array(
			'type'   => $this->type,
			'key'    => $this->key,
			'fixed'  => $this->fixed,
			'values' => $this->values,
		);
	}

	/**
	 * Shortcut: a fixed value.
	 *
	 * @param string $value Value.
	 */
	public static function fixed( string $value ): self {
		return new self(
			array(
				'type'  => self::FIXED,
				'fixed' => $value,
			)
		);
	}

	/**
	 * Shortcut: a WooCommerce attribute.
	 *
	 * @param string $name Attribute name (pa_color…).
	 */
	public static function attribute( string $name ): self {
		return new self(
			array(
				'type' => self::WC_ATTRIBUTE,
				'key'  => $name,
			)
		);
	}

	/**
	 * Shortcut: a product field.
	 *
	 * @param string $field Field name.
	 */
	public static function field( string $field ): self {
		return new self(
			array(
				'type' => self::FIELD,
				'key'  => $field,
			)
		);
	}
}