<?php

/**
 * WpCafe Discount Base Tool
 *
 * @package Aisentic\Integrations\WpCafe
 */

declare(strict_types=1);

namespace Aisentic\Integrations\WpCafe;

use Aisentic\Integrations\WpCafe\Wpcafe_Base_Tool;

defined( 'ABSPATH' ) || exit;

/**
 * Shared base for all WpCafe discount tools.
 *
 * Centralises the Pro-plugin + module guard, the discount data shaper, the
 * product_rule / date_rule array builders, and the enum validators. Each
 * concrete tool extends this class instead of Wpcafe_Base_Tool directly.
 */
abstract class Wpcafe_Discount_Base_Tool extends Wpcafe_Base_Tool {

	/**
	 * Guard for WpCafe Pro availability and the Discount module being enabled.
	 *
	 * Checks class_exists() first because it is a free in-memory hash lookup,
	 * while wpc_is_module_enable() hits the options table and iterates the
	 * extension registry. When Pro is absent both checks fail; this order
	 * avoids the I/O cost on that common case.
	 *
	 * @return array|null Error array on failure, null on success.
	 */
	protected function guard_discount_pro(): ?array {
		if ( ! class_exists( '\WpCafePro\Models\Discount_Model' ) ) {
			return [ 'error' => 'WpCafe Pro is not installed. Discounts require WpCafe Pro.' ];
		}

		if ( ! wpc_is_module_enable( 'discount' ) ) {
			return [ 'error' => 'The Discount module is not enabled. Go to WpCafe → Extensions to enable it.' ];
		}

		return null;
	}

	/**
	 * Shape a Discount_Model instance into an AI-friendly flat array.
	 *
	 * WordPress unserialises post meta on read, so maybe_unserialize() is a
	 * no-op on arrays but safely handles any edge case where the raw string
	 * is returned (e.g. a meta value stored before the model existed).
	 *
	 * @param \WpCafePro\Models\Discount_Model $discount Model instance.
	 * @return array
	 */
	protected function shape_discount( \WpCafePro\Models\Discount_Model $discount ): array {
		$date_rule    = maybe_unserialize( $discount->date_rule );
		$product_rule = maybe_unserialize( $discount->product_rule );

		return [
			'id'                        => $discount->id,
			'discount_title'            => $discount->discount_title,
			'discount_type'             => $discount->discount_type,
			'discount_amount'           => floatval( $discount->discount_amount ),
			'status'                    => $discount->discount_status,
			'is_active'                 => (bool) $discount->is_active,
			'product_rule'              => is_array( $product_rule ) ? $product_rule : [],
			'date_rule'                 => is_array( $date_rule ) ? $date_rule : [],
			'addon_discount_applicable' => $discount->addon_discount_applicable,
		];
	}

	/**
	 * Build the product_rule array accepted by Discount_Model::create/update.
	 *
	 * @param string|null $rule_type           Product scope type.
	 * @param array|null  $specific_products   WC product IDs to include.
	 * @param array|null  $excluded_products   WC product IDs to exclude.
	 * @param array|null  $specific_categories WC category IDs to include.
	 * @return array
	 */
	protected function build_product_rule(
		?string $rule_type,
		?array $specific_products,
		?array $excluded_products,
		?array $specific_categories
	): array {
		return [
			'type'                => $rule_type ?? 'all_products',
			'specific_products'   => array_map( 'intval', $specific_products ?? [] ),
			'excluded_products'   => array_map( 'intval', $excluded_products ?? [] ),
			'specific_categories' => array_map( 'intval', $specific_categories ?? [] ),
		];
	}

	/**
	 * Build the date_rule array accepted by Discount_Model::create/update.
	 *
	 * Returns an empty array when $rule_type is null (no date rule).
	 *
	 * @param string|null $rule_type   Date rule type.
	 * @param string|null $date        Exact date (Y-m-d) for on_date.
	 * @param string|null $start_date  Start date (Y-m-d) for date_range.
	 * @param string|null $end_date    End date (Y-m-d) for date_range.
	 * @param string|null $start_time  Start time (HH:MM) for time_range.
	 * @param string|null $end_time    End time (HH:MM) for time_range.
	 * @param array|null  $days        Day abbreviations for day_of_week.
	 * @return array
	 */
	protected function build_date_rule(
		?string $rule_type,
		?string $date,
		?string $start_date,
		?string $end_date,
		?string $start_time,
		?string $end_time,
		?array $days
	): array {
		if ( null === $rule_type ) {
			return [];
		}

		return [
			'type'       => sanitize_text_field( $rule_type ),
			'date'       => sanitize_text_field( $date ?? '' ),
			'start_date' => sanitize_text_field( $start_date ?? '' ),
			'end_date'   => sanitize_text_field( $end_date ?? '' ),
			'start_time' => sanitize_text_field( $start_time ?? '' ),
			'end_time'   => sanitize_text_field( $end_time ?? '' ),
			'days'       => array_map( 'sanitize_text_field', $days ?? [] ),
		];
	}

	/**
	 * Validate that a discount_type value is an accepted enum member.
	 *
	 * @param string $type Value to validate.
	 * @return array|null Error array on failure, null on success.
	 */
	protected function validate_discount_type( string $type ): ?array {
		if ( ! in_array( $type, [ 'percentage', 'fixed_amount', 'standard' ], true ) ) {
			return [ 'error' => "Invalid discount_type \"{$type}\". Accepted: percentage, fixed_amount, standard." ];
		}

		return null;
	}

	/**
	 * Validate that a discount_status value is an accepted enum member.
	 *
	 * @param string $status Value to validate.
	 * @return array|null Error array on failure, null on success.
	 */
	protected function validate_discount_status( string $status ): ?array {
		if ( ! in_array( $status, [ 'active', 'inactive' ], true ) ) {
			return [ 'error' => "Invalid discount_status \"{$status}\". Accepted: active, inactive." ];
		}

		return null;
	}

	/**
	 * Validate that an addon_discount_applicable value is an accepted enum member.
	 *
	 * @param string $applicable Value to validate.
	 * @return array|null Error array on failure, null on success.
	 */
	protected function validate_addon_applicable( string $applicable ): ?array {
		if ( ! in_array( $applicable, [ 'total_amount', 'addons_total_amount' ], true ) ) {
			return [ 'error' => "Invalid addon_discount_applicable \"{$applicable}\". Accepted: total_amount, addons_total_amount." ];
		}

		return null;
	}
}