calss-wc-memberships-member-discounts.php

<?php
/**
 * WooCommerce Memberships
 *
 * This source file is subject to the GNU General Public License v3.0
 * that is bundled with this package in the file license.txt.
 * It is also available through the world-wide-web at this URL:
 * http://www.gnu.org/licenses/gpl-3.0.html
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@skyverge.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade WooCommerce Memberships to newer
 * versions in the future. If you wish to customize WooCommerce Memberships for your
 * needs please refer to http://docs.woothemes.com/document/woocommerce-memberships/ for more information.
 *
 * @package   WC-Memberships/Classes
 * @author    SkyVerge
 * @copyright Copyright (c) 2014-2016, SkyVerge, Inc.
 * @license   http://www.gnu.org/licenses/gpl-3.0.html GNU General Public License v3.0
 */

defined( 'ABSPATH' ) or exit;

/**
 * Member Discounts class
 *
 * This class handles all purchasing discounts for members
 *
 * @since 1.3.0
 */
class WC_Memberships_Member_Discounts {


    /** @var array Lazy loading for member product discount information */
    private $member_has_product_discount = array();

    /** @var array Memoization for product discounts */
    private $product_discount = array();

    /** @var array Memoization for variation product discounts */
    private $product_discount_variation = array();

    /** @var array Memoization for product discounts exclusion */
    private $product_excluded_from_discounts = array();

    /** @var bool Whether products on sale are excluded from discounts */
    private $exclude_on_sale_products = false;

    /** @var array Memoization for product on sale before discount */
    private $product_is_on_sale_before_discount = array();

    /** @var bool Whether the current user, maybe member, is logged in */
    private $member_is_logged_in = false;

    /** @var bool Whether discounts calculations are running for products  */
    private $applying_discounts = false;


    /**
     * Set up member discounts: Welcome to the jungle.
     *
     * @since 1.3.0
     */
    public function __construct() {

        // init discounts so we don't hook to early
        add_action( 'init', array( $this, 'init' ) );
    }


    /**
     * Init member discounts
     *
     * We follow here a pattern common in many price-affecting extensions,
     * due to the need to produce a "price before/after discount" type of HTML output,
     * so shop customers can easily understand the deal they're being offered.
     *
     * To do so we need to juggle WooCommerce prices, we start off by instantiating
     * this class with our discounts active, so we can be sure to always pass those
     * to other extensions if a member is logged in. Then, when we want to show prices
     * in front end we need to deactivate price modifications, compare the original
     * price with the price resulting from discount calculations and if a discount is
     * found (price difference) we strikethrough the original price to show what it was
     * like before discount, so we reactivate price modifiers, and finally show prices
     * after modifications.
     *
     * Extensions and third party code that need to know if Memberships price modifiers
     * are being applied or not in these two phases, can use doing_action and hook into
     * 'wc_memberships_discounts_enable_price_adjustments' and
     * 'wc_memberships_discounts_disable_price_adjustments' (and their html counterparts)
     * or call directly the callbacks found in this class, which we use to add and remove
     * price modifier filters. Or, if there's need to deactivate or activate Memberships
     * price modifiers directly, the public callback methods that these actions use could
     * also be invoked for this purpose.
     *
     * @see \WC_Memberships_Member_Discounts::enable_price_adjustments()
     * @see \WC_Memberships_Member_Discounts::disable_price_adjustments()
     *
     * @internal
     *
     * @since 1.7.1
     */
    public function init() {

        $this->member_is_logged_in      = wc_memberships_is_user_member( get_current_user_id() );
        $this->exclude_on_sale_products = 'yes' === get_option( 'wc_memberships_exclude_on_sale_products_from_member_discounts', 'no' );

        // refreshes the mini cart upon member login
        add_action( 'wp_login', array( $this, 'refresh_cart_upon_member_login' ), 10, 2 );

        // member discount class methods are available on both frontend and backend
        // but the hooks below should run in frontend only for logged in members
        if ( ! ( is_admin() && ! is_ajax() ) ) {

            if ( $this->member_is_logged_in ) {

                $this->applying_discounts = true;

                // initialize discount actions that will be called in this class methods
                add_action( 'wc_memberships_discounts_enable_price_adjustments',       array( $this, 'enable_price_adjustments' ) );
                add_action( 'wc_memberships_discounts_enable_price_html_adjustments',  array( $this, 'enable_price_html_adjustments' ) );
                add_action( 'wc_memberships_discounts_disable_price_adjustments',      array( $this, 'disable_price_adjustments' ) );
                add_action( 'wc_memberships_discounts_disable_price_html_adjustments', array( $this, 'disable_price_html_adjustments' ) );

                // start off by activating discounts for logged in members
                do_action( 'wc_memberships_discounts_enable_price_adjustments' );
                do_action( 'wc_memberships_discounts_enable_price_html_adjustments' );

                // force calculations in cart
                add_filter( 'woocommerce_update_cart_action_cart_updated', '__return_true' );
                // adjust cart items prices
                add_filter( 'woocommerce_cart_item_price', array( $this, 'on_cart_item_price' ), 999, 2 );

                // member discount badges
                add_action( 'woocommerce_before_shop_loop_item_title',   'wc_memberships_show_product_loop_member_discount_badge' );
                add_action( 'woocommerce_before_single_product_summary', 'wc_memberships_show_product_member_discount_badge' );
                add_filter( 'wc_memberships_member_discount_badge',      array( $this, 'disable_discount_badge_for_excluded_products' ), 10, 3 );

                // make sure that the display of the "On Sale" badge is honoured
                add_filter( 'woocommerce_product_is_on_sale', array( $this, 'product_is_on_sale' ), 999, 2 );

                // if a product is on sale and has a member discount, optionally show the sale badge
                add_action( 'woocommerce_single_product_summary', array( $this, 'display_sale_badge_for_discounted_products' ), 1 );
                add_action( 'woocommerce_shop_loop_item_title',   array( $this, 'display_sale_badge_for_discounted_products' ), 1 );

            } else {

                $this->applying_discounts = false;

                // ensures 'wc_memberships_get_price_html' filter hook is fired nonetheless
                add_filter( 'woocommerce_get_price_html', array( $this, 'on_price_html' ), 999, 2 );
            }
        }
    }


    /*
     * Check if the logged in member has membership discounts for a product
     *
     * @since 1.6.4
     * @param int|\WC_Product|\WC_Product_Variable|null $the_product Optional, a product id or object to check if it has member discounts
     *                                                               (if not set, looks for a current product)
     * @param int|\WP_User|null $the_user Optional, the user to check if has discounts for the product
     *                                    (defaults to current user)
     * @return bool
     */
    public function user_has_member_discount( $the_product = null, $the_user = null ) {

        $has_discount = false;

        // get the product
        if ( is_numeric( $the_product ) ) {
            $the_product = wc_get_product( $the_product );
        } elseif ( null === $the_product ) {
            global $product;

            if ( $product instanceof WC_Product ) {
                $the_product = $product;
            }
        }

        // bail out if no product
        if ( ! $the_product instanceof WC_Product ) {
            return $has_discount;
        }

        // get the user id
        if ( null === $the_user ) {
            $member_id = get_current_user_id();
        } elseif ( is_numeric( $the_user ) ) {
            $member_id = (int) $the_user;
        } elseif ( isset( $the_user->ID ) ) {
            $member_id = (int) $the_user->ID;
        } else {
            return $has_discount;
        }

        // bail out if user is not logged in
        if ( 0 === $member_id ) {
            return $has_discount;
        }

        $product_id = SV_WC_Plugin_Compatibility::product_get_id( $the_product );

        // use memoized entry if found, or store a new one
        if ( isset( $this->member_has_product_discount[ $member_id ][ $product_id ] ) ) {

            $has_discount = $this->member_has_product_discount[ $member_id ][ $product_id ];

        } else {

            $has_discount = wc_memberships()->get_rules_instance()->user_has_product_member_discount( $member_id, $product_id );

            // if a variable product, before return false check for its variations
            if ( ! $has_discount && $the_product->has_child() ) {

                foreach ( $the_product->get_children() as $product_child_id ) {

                    $has_discount = wc_memberships()->get_rules_instance()->user_has_product_member_discount( $member_id, $product_child_id );

                    $this->member_has_product_discount[ $member_id ][ $product_child_id ] = $has_discount;

                    // if one of the child variations has a discount, it's legit
                    // to say that the parent variable product has member discounts
                    if ( $has_discount ) {
                        $this->member_has_product_discount[ $member_id ][ $product_id ] = $has_discount;
                        break;
                    // unlikely occurrence but if so we can break the loop earlier
                    } elseif ( $product_id === $product_child_id ) {
                        break;
                    }
                }

            } else {

                $this->member_has_product_discount[ $member_id ][ $product_id ] = $has_discount;
            }
        }

        return $has_discount;
    }


    /**
     * Check whether products on sale should be excluded from discount rules
     *
     * @since 1.7.0
     * @return bool
     */
    public function excluding_on_sale_products_from_member_discounts() {
        return $this->exclude_on_sale_products;
    }


    /**
     * Check if a product is to be excluded from discount rules
     *
     * Note: even if not excluded, discount rules may or may not still apply
     *
     * @since 1.7.0
     * @param int|\WC_Product $product Product object or id
     * @return bool
     */
    public function is_product_excluded_from_member_discounts( $product ) {

        if ( is_numeric( $product ) ) {
            $product = wc_get_product( $product );
        } elseif ( $product instanceof WP_Post ) {
            $product = wc_get_product( $product );
        } elseif ( ! $product instanceof WC_Product ) {
            return false;
        }

        $product_id = SV_WC_Plugin_Compatibility::product_get_id( $product );

        // use memoization to speed up checks
        if ( isset( $this->product_excluded_from_discounts[ $product_id ] ) ) {

            $exclude = $this->product_excluded_from_discounts[ $product_id ];

        } else {

            // exclude if product-level setting is enabled to exclude this product
            $exclude_product = 'yes' === get_post_meta( $product_id, '_wc_memberships_exclude_discounts', true );
            // exclude if on sale and global-level setting is enabled to exclude all products on sale
            $exclude_on_sale = $this->excluding_on_sale_products_from_member_discounts() && $this->product_is_on_sale_before_discount( $product );

            /**
             * Filter product from having discount rules applied
             *
             * @since 1.7.0
             * @param bool $exclude Whether the product is excluded from discount rules
             * @param \WC_Product $product The product object
             */
            $exclude = (bool) apply_filters( 'wc_memberships_exclude_product_from_member_discounts', $exclude_product || $exclude_on_sale, $product );

            $this->product_excluded_from_discounts[ $product_id ] = $exclude;
        }

        return $exclude;
    }


    /**
     * Handle sale status of products
     *
     * @since 1.6.2
     * @param bool $on_sale Whether the product is on sale
     * @param \WC_Product|\WC_Product_Variable $product The product object
     * @return bool
     */
    public function product_is_on_sale( $on_sale, $product ) {

        // bail out if any of the following:
        // - user is not logged in
        // - product is being excluded from member discounts
        // - global Memberships setting is excluding on sale products from discounts
        // - current user does not have a discount for the product that may be on sale
        if (    ! $this->member_is_logged_in
             ||   $this->is_product_excluded_from_member_discounts( $product )
             ||   ( $on_sale && $this->excluding_on_sale_products_from_member_discounts() )
             ||   ( ! is_admin() && ( ! $product instanceof WC_Product || ( $this->member_is_logged_in && ! $this->user_has_member_discount( SV_WC_Plugin_Compatibility::product_get_id( $product ) ) ) ) ) ) {

            return $on_sale;
        }

        return $this->product_is_on_sale_before_discount( $product );
    }


    /**
     * Determine if a product is on sale before membership price adjustments
     *
     * This method contains code from
     * @see WC_Product::is_on_sale()
     * and
     * @see WC_Product_Variable::is_on_sale()
     * It was introduced mainly to avoid infinite loops between
     * @see \WC_Memberships_Member_Discounts::product_is_on_sale()
     * and
     * @see \WC_Memberships_Member_Discounts::is_product_excluded_from_member_discounts()
     * so it runs very late from
     * @see \WC_Memberships_Member_Discounts::product_is_on_sale()
     * and does not include itself the product on sale filter that would cause
     * the infinite loop, and also will remove all other filters on
     * 'woocommerce_product_is_on_sale' if our own filter is running
     *
     * @since 1.7.0
     * @param int|\WC_Product|\WC_Product_Variable $product Product object or id
     * @return bool
     */
    public function product_is_on_sale_before_discount( $product ) {

        if ( is_numeric( $product ) ) {
            $product = wc_get_product( $product );
        }

        $on_sale = false;

        // sanity checks
        if ( ! $product instanceof WC_Product ) {
            return $on_sale;
        } elseif ( ! $this->member_is_logged_in ) {
            return $product->is_on_sale();
        }

        $product_id = SV_WC_Plugin_Compatibility::product_get_id( $product );

        if ( isset( $this->product_is_on_sale_before_discount[ $product_id ] ) ) {

            $on_sale = $this->product_is_on_sale_before_discount[ $product_id ];

        } else {

            // disable Memberships member discount adjustments
            do_action( 'wc_memberships_discounts_disable_price_adjustments' );

            /** @see WC_Product_Variable::is_on_sale() */
            if ( $product->is_type( array( 'variable', 'variable-subscription' ) ) ) {

                $prices  = $product->get_variation_prices();

                if ( $prices['regular_price'] !== $prices['sale_price'] && $prices['sale_price'] === $prices['price'] ) {
                    $on_sale = true;
                }

            /** @see WC_Product::is_on_sale() */
            } else {

                $on_sale = $product->get_sale_price() !== $product->get_regular_price() && $product->get_sale_price() === $product->get_price();
            }

            // re-enable Memberships member discount adjustments
            do_action( 'wc_memberships_discounts_enable_price_adjustments' );

            $this->product_is_on_sale_before_discount[ $product_id ] = $on_sale;
        }

        // we need this to avoid conflicts with third party code that runs
        // again 'woocommerce_product_is_on_sale' filter - since Memberships
        // runs its own filter very late (priority 999) it's safe enough
        // to make Memberships' filter final
        if ( 'woocommerce_product_is_on_sale' === current_filter() ) {

            /** @see \WC_Memberships_Member_Discounts::__construct() */
            /** @see \WC_Memberships_Member_Discounts::product_is_on_sale)() */
            remove_all_filters( 'woocommerce_product_is_on_sale' );
        }

        return $on_sale;
    }


    /**
     * Display sale badge for discounted products
     *
     * @since 1.7.0
     */
    public function display_sale_badge_for_discounted_products() {
        global $post;

        $product = wc_get_product( $post );

        // sanity check
        if ( ! $product instanceof WC_Product ) {
            return;
        }

        /**
         * Controls whether or not member prices should display sale prices as well
         *
         * @since 1.3.0
         * @param bool $display_sale_price Defaults to false
         */
        $display_sale_price = (bool) apply_filters( 'wc_memberships_member_prices_display_sale_price', false );

        // determine whether the product is on sale in the first place
        $on_sale_before_discount = $this->product_is_on_sale_before_discount( $product );
        $member_has_discount     = $this->user_has_member_discount( $product );

        // show this badge if:
        // - user has a member discount, product is on sale and we want to display the sale price badge
        // - user does NOT have a member discount, but product is on sale before discount rules (compatibility)
        if (    (   $member_has_discount && $on_sale_before_discount && $display_sale_price )
             || ( ( ! $member_has_discount || $this->is_product_excluded_from_member_discounts( $product ) ) && $on_sale_before_discount ) ) {

            add_filter( 'woocommerce_product_is_on_sale',    array( $this, 'enable_sale_price' ) );

            wc_get_template( 'single-product/sale-flash.php' );

            remove_filter( 'woocommerce_product_is_on_sale', array( $this, 'enable_sale_price' ) );
        }
    }


    /**
     * Enable 'on sale' callback for a product that is on sale before discounts
     *
     * @internal
     *
     * @since 1.7.0
     * @return true
     */
    public function enable_sale_price() {
        return true;
    }


    /**
     * Disable 'on sale' callback for a product that is on sale before discounts
     *
     * @internal
     *
     * @since 1.3.0
     * @return true
     */
    public function disable_sale_price() {
        return false;
    }


    /**
     * Get product price before discount
     *
     * @since 1.7.0
     * @param \WC_Product|\WC_Product_Variation $product Product
     * @return float Price
     */
    private function get_price_before_discount( $product ) {

        // temporarily disable price adjustments
        do_action( 'wc_memberships_discounts_disable_price_adjustments' );

        // get the base price without discounts
        $price = $product->get_display_price();

        // re-enable price adjustments
        do_action( 'wc_memberships_discounts_enable_price_adjustments' );

        return $price;
    }


    /**
     * Apply purchasing discounts to product price
     *
     * @internal
     *
     * @since 1.0.0
     * @param string|int|float $price Price to discount (normally a float, maybe a string number)
     * @param \WC_Product $product The product object
     * @return float Price
     */
    public function on_get_price( $price, $product ) {

        // bail out if any of the following is true:
        // - member is not logged in
        // - product is excluded from member discounts
        // - user has no member discount over the product
        if (    ! $this->member_is_logged_in
             ||   $this->is_product_excluded_from_member_discounts( $product )
             || ! $this->user_has_member_discount( $product ) ) {

            $price = $this->get_price_before_discount( $product );

        } else {

            // get the discounted price or return the default price if no discounts apply
            $discounted_price = $this->get_discounted_price( $price, $product );

            $price = is_numeric( $discounted_price ) ? $discounted_price : $this->get_price_before_discount( $product );
        }

        return (float) $price;
    }


    /**
     * Get variable product price HTML before membership discounts
     *
     * @see \WC_Product_Variable::get_price_html()
     *
     * @since 1.7.1
     * @param \WC_Product_Variable $product Variable product
     * @param bool $display_sale_price Whether to display sale price
     * @return string HTML
     */
    private function get_variable_product_price_html_before_discount( $product, $display_sale_price ) {

        $prices = $product->get_variation_prices( true );

        if ( empty( $prices['price'] ) || '' === $product->get_price() ) {

            $html_before_discount = apply_filters( 'woocommerce_variable_empty_price_html', '', $product );

        } else {

            $regular_min = $sale_min = $product->get_variation_regular_price( 'min', true );
            $regular_max = $sale_max = $product->get_variation_regular_price( 'max', true );

            $regular_price = $regular_min !== $regular_max ? sprintf( _x( '%1$s&ndash;%2$s', 'Price range: from-to', 'woocommerce-memberships' ), wc_price( $regular_min ), wc_price( $regular_max ) ) : wc_price( $regular_min );

            if ( $on_sale = $this->product_is_on_sale_before_discount( $product ) ) {

                $sale_min = $product->get_variation_sale_price( 'min', true );
                $sale_max = $product->get_variation_sale_price( 'max', true );

                $sale_price = $sale_min !== $sale_max ? sprintf( _x( '%1$s&ndash;%2$s', 'Price range: from-to', 'woocommerce-memberships' ), wc_price( $sale_min ), wc_price( $sale_max ) ) : wc_price( $sale_min );

                if ( $this->user_has_member_discount( $product ) ) {
                    $html_before_discount = $display_sale_price ? apply_filters( 'woocommerce_variable_sale_price_html', $sale_price, $product ) : $regular_price;
                } else {
                    $html_before_discount = $html = '<del>' . $regular_price . '</del> <ins>' . $sale_price . '</ins>';
                    $html_before_discount = apply_filters( 'woocommerce_variable_sale_price_html', $html_before_discount, $product );
                }

            } else {

                $html_before_discount = $regular_price;
            }

            // sanity check for free products:
            // if min and max variations are 0, this product is free
            $min_price = (float) current( $prices['price'] );
            $max_price = (float) end( $prices['price'] );

            if ( empty( $min_price ) && empty( $max_price ) ) {
                $html_before_discount = apply_filters( 'woocommerce_variable_free_price_html', _x( 'Free!', 'Free product', 'woocommerce-memberships' ), $product );
            }
        }

        return $html_before_discount;
    }


    /**
     * Get void product price HTML before membership discounts
     *
     * @see \WC_Product::get_price_html()
     *
     * @since 1.7.1
     * @param \WC_Product $product Product object
     * @return string HTML
     */
    private function get_void_product_price_html_before_discount( $product ) {

        $price = $product->get_price();

        if ( empty( $price ) && '' !== $price ) {

            if ( $this->product_is_on_sale_before_discount( $product ) && $product->get_regular_price() ) {

                $price_label = $product->get_price_html_from_to( $product->get_display_price( $product->get_regular_price() ), _x( 'Free!', 'Free product', 'woocommerce-memberships' ) );

                $html_before_discount = apply_filters( 'woocommerce_free_sale_price_html', $price_label, $this );

            } else {

                $html_before_discount = apply_filters( 'woocommerce_free_price_html', _x( 'Free!', 'Free product', 'woocommerce-memberships' ), $product );
            }

        } else {

            $html_before_discount = apply_filters( 'woocommerce_empty_price_html', '', $product );
        }

        return $html_before_discount;
    }


    /**
     * Get simple or variation product price before membership discounts
     *
     * @see \WC_Product::get_price_html()
     * @see \WC_Product_Variation::get_price_html()
     *
     * @since 1.7.1
     * @param \WC_Product|\WC_Product_Variation $product A simple product or a variation
     * @param bool $display_sale_price Whether to display sale prices
     * @return string HTML
     */
    private function get_product_price_html_before_discount( $product, $display_sale_price ) {

        $on_sale      = $this->product_is_on_sale_before_discount( $product );
        $is_variation = $product->is_type( 'variation' );

        if ( $is_variation && '' === $product->get_price() ) {

            $html_before_discount = apply_filters( 'woocommerce_variation_empty_price_html', '', $product );

        } else {

            if ( $this->user_has_member_discount( $product ) && ! $this->is_product_excluded_from_member_discounts( $product ) )  {

                if ( $on_sale ) {
                    $price_before_discount = $display_sale_price ? $product->get_display_price( $product->get_sale_price() ) : $product->get_display_price( $product->get_regular_price() );
                    $html_before_discount  = wc_price( $price_before_discount );
                } else {
                    $price_before_discount = $product->get_display_price( $product->get_regular_price() );
                    $html_before_discount  = wc_price( $price_before_discount );
                }

            } else {

                if ( $on_sale ) {
                    $html_before_discount  = $product->get_price_html_from_to( $product->get_display_price( $product->get_regular_price() ), $product->get_display_price( $product->get_sale_price() ) );
                } else {
                    $price_before_discount = $product->get_display_price( $product->get_regular_price() );
                    $html_before_discount  = wc_price( $price_before_discount );
                }
            }

            // maybe apply wc filters before returning
            if ( $on_sale ) {
                $sale_price_html_filter = $is_variation ? 'woocommerce_variation_sale_price_html' : 'woocommerce_sale_price_html';
                $html_before_discount   = apply_filters( $sale_price_html_filter, $html_before_discount, $product );
            } elseif ( $is_variation && ! $product->get_price() > 0 ) {
                $html_before_discount = apply_filters( 'woocommerce_variation_free_price_html', _x( 'Free!', 'Free product', 'woocommerce-memberships' ), $product );
            }
        }

        return $html_before_discount;
    }


    /**
     * Get product HTML price before discount
     *
     * @since 1.7.0
     * @param \WC_Product|\WC_Product_Variable|\WC_Product_Variation $product Product
     * @return string HTML
     */
    private function get_price_html_before_discount( $product ) {

        /**
         * Controls whether or not member prices should display sale prices as well
         *
         * @since 1.3.0
         * @param bool $display_sale_price Defaults to false
         */
        $display_sale_price = (bool) apply_filters( 'wc_memberships_member_prices_display_sale_price', false );

        // temporarily disable membership price adjustments
        do_action( 'wc_memberships_discounts_disable_price_adjustments' );
        do_action( 'wc_memberships_discounts_disable_price_html_adjustments' );

        if ( ! $product->get_price() && ! $product->is_type( array( 'variable', 'variation' ) ) ) {
            // simple products with 0 or empty price
            $html_before_discount = $this->get_void_product_price_html_before_discount( $product );
        } elseif ( $product->is_type( 'variable' ) ) {
            // variable products
            $html_before_discount = $this->get_variable_product_price_html_before_discount( $product, $display_sale_price );
        } else {
            // simple products with non-void prices, product variations
            $html_before_discount = $this->get_product_price_html_before_discount( $product, $display_sale_price );
        }

        // re-enable membership price adjustments
        do_action( 'wc_memberships_discounts_enable_price_adjustments' );
        do_action( 'wc_memberships_discounts_enable_price_html_adjustments' );

        return $html_before_discount . $product->get_price_suffix( $this->get_price_before_discount( $product ) );
    }


    /**
     * Adjust discounted product price HTML
     *
     * @internal
     *
     * @since 1.3.0
     * @param string $html The price HTML maybe after discount
     * @param \WC_Product|\WC_Product_Variable|\WC_Product_Variation $product The product object for which we may have discounts
     * @return string The original price HTML if no discount or a new formatted string showing before/after discount
     */
    public function on_price_html( $html, $product ) {

        /**
         * Controls whether or not member prices should use discount format when displayed
         *
         * @since 1.3.0
         * @param bool $use_discount_format Defaults to true
         */
        $use_discount_format = (bool) apply_filters( 'wc_memberships_member_prices_use_discount_format', true );

        // bail out if any of the following conditions applies:
        // - custom code set to not to use discount format
        // - no member user is logged in
        // - product is excluded from discount rules
        // - current user has no discounts for the product
        // - product has no applicable member discount
        if (    ! $use_discount_format
             || ! $this->member_is_logged_in
             ||   $this->is_product_excluded_from_member_discounts( $product )
             || ! $this->user_has_member_discount( $product ) ) {

            if ( $this->applying_discounts ) {
                $html = $this->get_price_html_before_discount( $product );
            }

        } else {

            if ( $product->is_type( 'variable' ) ) {

                $price_min = $product->get_variation_price( 'min', true );
                $price_min = $price_min > 0 ? $this->get_discounted_price( $price_min, $product ) : 0;
                $price_max = $product->get_variation_price( 'max', true );
                $price_max = $price_max > 0 ? $this->get_discounted_price( $price_max, $product ) : 0;

                // this may be a case when one or more product variations
                // have discounts but the parent variable product has none
                if ( empty( $price_min ) && empty( $price_max ) && ( $variations = $product->get_children() ) ) {

                    $variation_prices = array();

                    foreach ( $variations as $variation_id ) {
                        $variation_prices[] = wc_get_product( $variation_id )->get_display_price();
                    }

                    if ( ! empty( $variation_prices ) ) {
                        $price_min = min( $variation_prices );
                        $price_max = max( $variation_prices );
                    }
                }

                if ( $price_min !== $price_max ) {
                    $html_after_discount = sprintf( _x( '%1$s&ndash;%2$s', 'Price range: from-to', 'woocommerce-memberships' ), wc_price( $price_min ), wc_price( $price_max ) );
                } elseif ( empty( $price_min ) && empty( $price_max ) ) {
                    $html_after_discount = $this->get_void_product_price_html_before_discount( $product );
                } else {
                    $html_after_discount = wc_price( $price_min );
                }

                $html_after_discount .= $product->get_price_suffix( $product->get_price() );

            } else {

                $html_after_discount = $html;
            }

            $html_before_discount = $this->get_price_html_before_discount( $product );

            // string prices do not match, we have a discount
            if ( $html_after_discount !== $html_before_discount ) {

                $html = '<del>' . $html_before_discount . '</del> <ins>' . $html_after_discount . '</ins>';

                if ( ! $product->is_type( 'variable' ) ) {

                    $price_before_discount = $this->get_price_before_discount( $product );
                    $price_after_discount  = $product->get_price();

                    if ( empty( $price_before_discount ) && empty( $price_after_discount ) ) {

                        $html = $html_after_discount;
                    }
                }
            }

            // add a "Member Discount" badge for single variation prices
            if ( $product->is_type( 'variation' ) ) {

                $html .= ' ' . $this->get_member_discount_badge( $product, true );
            }
        }

        /**
         * Filter the HTML price after member discounts may have been applied
         *
         * @since 1.7.1
         * @param string $price_html The price HTML
         * @param \WC_Product $product The product the price is meant for
         */
        return apply_filters( 'wc_memberships_get_price_html', $html, $product );
    }


    /**
     * Adjust variation price
     *
     * @internal
     *
     * @since 1.3.0
     * @param float $price The product price, maybe discounted
     * @param \WC_Product|\WC_Product_Variation $product The product object
     * @param string $min_or_max Min-max prices of variations
     * @param bool $display If to be displayed
     * @return float
     */
    public function on_get_variation_price( $price, $product, $min_or_max, $display ) {

        // bail out if any of the following applies:
        // - no user member is logged in
        // - the product is excluded from receiving member discounts
        // - logged in user has no member discount over the product
        if (    ! $this->member_is_logged_in
             || ! $product instanceof WC_Product
             ||   $this->is_product_excluded_from_member_discounts( $product )
             || ! $this->user_has_member_discount( $product ) ) {

            $price_float = (float) $price;

            return $this->applying_discounts && empty( $price_float ) ? $this->get_price_before_discount( $product ) : $price;
        }

        $product_id = SV_WC_Plugin_Compatibility::product_get_id( $product );

        // use memoized entry if available to speed up return
        if ( isset( $this->product_discount_variation[ $product_id ][ $min_or_max ] ) ) {

            $price = $this->product_discount_variation[ $product_id ][ $min_or_max ];

        } else {

            // defaults
            $calc_price = $price;
            $min_price  = $price;
            $max_price  = $price;

            // get variation ids
            $children = $product->get_children();

            if ( ! empty( $children ) ) {

                foreach ( $children as $variation_id ) {

                    if ( $display ) {

                        if ( $variation = $product->get_child( $variation_id ) ) {

                            // make sure we start from the normal un-discounted price
                            do_action( 'wc_memberships_discounts_disable_price_adjustments' );

                            // in display mode, we need to account for taxes
                            $base_price = $variation->get_price() > 0 ? $variation->get_display_price() : 0;
                            $calc_price = $base_price;

                            // try getting the discounted price for the variation
                            $discounted_price = $this->get_discounted_price( $base_price, $variation->id );

                            // if there's a difference, grab discounted price
                            if ( is_numeric( $discounted_price ) && $base_price !== $discounted_price ) {
                                $calc_price = $discounted_price;
                            }

                            // re-enable discounts in pricing flow
                            do_action( 'wc_memberships_discounts_enable_price_adjustments' );
                        }

                    } else {

                        $calc_price = (float) get_post_meta( $variation_id, '_price', true );
                    }

                    if ( $min_price === null || $calc_price < $min_price ) {
                        $min_price = $calc_price;
                    }

                    if ( $max_price === null || $calc_price > $max_price ) {
                        $max_price = $calc_price;
                    }
                }
            }

            if ( $min_or_max === 'min' ) {
                $price = (float) $min_price;
            } elseif ( $min_or_max === 'max' ) {
                $price = (float) $max_price;
            }

            $this->product_discount_variation[ $product_id ][ $min_or_max ] = $price;
        }

        return (float) $price;
    }


    /**
     * Adjust discounted cart item price HTML
     *
     * @internal
     *
     * @since 1.3.0
     * @param string $html Price HTML
     * @param array $cart_item The cart item data
     * @return string
     */
    public function on_cart_item_price( $html, $cart_item ) {

        // get the product
        $product = ! empty( $cart_item['data'] ) ? $cart_item['data'] : false;

        // bail out if any of the following applies:
        // - no user member is logged in
        // - no product (sanity check)
        // - the product is excluded from receiving member discounts
        // - logged in user has no member discount over the product
        if (    ! $this->member_is_logged_in
             || ! $product instanceof WC_Product
             ||   $this->is_product_excluded_from_member_discounts( $product )
             || ! $this->user_has_member_discount( $product ) ) {

            return $html;
        }

        // temporarily disable our price adjustments
        do_action( 'wc_memberships_discounts_disable_price_adjustments' );

        // so we can get the base price without member discounts
        // also, in cart we need to account for tax display
        $price = $product->get_display_price();

        // re-enable disable our price adjustments
        do_action( 'wc_memberships_discounts_enable_price_adjustments' );

        if ( $this->has_discounted_price( $price, $product ) ) {

            // in cart, we need to account for tax display
            $discounted_price = $product->get_display_price();

            /** This filter is documented in class-wc-memberships-member-discounts.php **/
            $use_discount_format = apply_filters( 'wc_memberships_use_discount_format', true );

            // output html price before/after discount
            if ( $use_discount_format && $discounted_price < $price ) {
                $html = '<del>' . wc_price( $price ) . '</del> <ins>' . wc_price( $discounted_price ) . '</ins>';
            }
        }

        return $html;
    }


    /**
     * Add the current user ID to the variation prices hash for caching.
     *
     * @internal
     *
     * @since 1.3.2
     * @param array $data The existing hash data
     * @param \WC_Product $product The current product variation
     * @return array $data The hash data with a user ID added if applicable
     */
    public function set_user_variation_prices_hash( $data, $product ) {

        // bail out if member is not logged in
        // or logged in user has no membership discount over the product
        if (      $this->member_is_logged_in
             && ! $this->is_product_excluded_from_member_discounts( $product )
             &&   $this->user_has_member_discount( $product ) ) {

            $data[] = get_current_user_id();
        }

        return $data;
    }


    /**
     * Get member discount badge
     *
     * @since 1.6.4
     * @param \WC_Product $product The product object to output a badge for (passed to filter)
     * @param bool $variation Whether to output a discount badge specific for a product variation (default false)
     * @return string
     */
    public function get_member_discount_badge( $product, $variation = false ) {

          $label = __( 'Member discount!', 'woocommerce-memberships' );
        // we have a slight different output for badge classes and filter
        if ( true !== $variation ) {
            global $post;

            // used in filter for backwards compatibility reasons
            $the_post = $post;

            if ( ! $the_post instanceof WP_Post ) {
                $the_post = $product->post;
            }

            $badge = '<span class="onsale wc-memberships-member-discount">' . esc_html( $label ) . '</span>';

            /**
             * Filter the member discount badge
             *
             * @since 1.0.0
             * @param string $badge The badge HTML
             * @param \WP_Post $post The product post object
             * @param \WC_Product_Variation $variation The product variation
             */
            $badge = apply_filters( 'wc_memberships_member_discount_badge', $badge, $the_post, $product );

        } else {

            $badge = '<span class="wc-memberships-variation-member-discount">' . esc_html( $label ) . '</span>';

            /**
             * Filter the variation member discount badge
             *
             * @since 1.3.2
             * @param string $badge The badge HTML
             * @param \WC_Product|\WC_Product_Variation $variation The product variation
             */
            $badge = apply_filters( 'wc_memberships_variation_member_discount_badge', $badge, $product );

        }

        return $badge;
    }


    /**
     * Filter the member discount badge for products excluded
     * from member discount rules
     *
     * @internal
     *
     * @since 1.7.0
     * @param string $badge Badge HTML
     * @param \WP_Post $post The post object
     * @param \WC_Product $product The product object
     * @return string Empty string if product is excluded from member discounts
     */
    public function disable_discount_badge_for_excluded_products( $badge, $post, $product ) {
        return $this->is_product_excluded_from_member_discounts( $product ) ? '' : $badge;
    }


    /**
     * Get product discounted price for member
     *
     * @since 1.3.0
     * @param float $base_price Original price
     * @param int|\WC_Product $product Product ID or product object
     * @param int|null $member_id Optional, defaults to current user id
     * @return float|null The discounted price or null if no discount applies
     */
    public function get_discounted_price( $base_price, $product, $member_id = null ) {

        if ( ! $member_id ) {
            $member_id = get_current_user_id();
        }

        if ( ! is_object( $product ) ) {
            $product = wc_get_product( $product );
        }

        $price          = null;
        $product_id     = null;
        $discount_rules = array();

        // we need a product and a user to get a member discounted price
        if ( $product instanceof WC_Product && $member_id > 0 ) {

            $product_id     = SV_WC_Plugin_Compatibility::product_get_id( $product );
            $discount_rules = wc_memberships()->get_rules_instance()->get_user_product_purchasing_discount_rules( $member_id, $product_id );
        }

        if ( $product_id && ! empty( $discount_rules ) ) {

            if ( isset( $this->product_discount[ $member_id ][ $product_id ] ) ) {

                $price = $this->product_discount[ $member_id ][ $product_id ];

            } else {

                /**
                 * Filter whether to allow stacking product discounts
                 * for members of multiple plans with overlapping discount rules
                 * for the same products
                 *
                 * @since 1.7.0
                 *
                 * @param bool $allow_cumulative_discounts Default true (allow)
                 * @param int $member_id The user id discounts are calculated for
                 * @param \WC_Product $product The product object being discounted
                 */
                $allow_cumulative_discounts = apply_filters( 'wc_memberships_allow_cumulative_member_discounts', true, $member_id, $product );

                $price  = (float) $base_price;
                $prices = array();

                // find out the discounted price for the current user
                foreach ( $discount_rules as $rule ) {

                    switch ( $rule->get_discount_type() ) {

                        case 'percentage':
                            $discounted_price = $price * ( 100 - $rule->get_discount_amount() ) / 100;
                        break;

                        case 'amount':
                            $discounted_price = $price - $rule->get_discount_amount();
                        break;
                    }

                    // make sure that the lowest price gets applied and doesn't become negative
                    if ( isset( $discounted_price ) && $discounted_price < $price ) {

                        if ( true === $allow_cumulative_discounts ) {
                            $price = max( $discounted_price, 0 );
                        } else {
                            $prices[] = max( $discounted_price, 0 );
                        }
                    }
                }

                // pick the lowest price
                if ( ! empty( $prices ) ) {
                    $price = min( $prices );
                }

                // sanity check
                if ( $price >= $base_price ) {
                    $price = null;
                }

                $this->product_discount[ $product_id ] = $price;
            }
        }

        /**
         * Filter discounted price of a membership product
         *
         * @since 1.7.1
         * @param null|float $price The discounted price or null if no discount applies
         * @param float $base_price The original price (not discounted by Memberships)
         * @param int $product_id The id of the product (or variation) the price is for
         * @param int $member_id THe id of the logged in member (it's zero for non logged in users)
         */
        return apply_filters( 'wc_memberships_get_discounted_price', $price, $base_price, $product_id, $member_id );
    }


    /**
     * Check if the product is discounted for the user
     *
     * @since 1.3.0
     * @param float $base_price Original price
     * @param int|\WC_Product $product Product ID or object
     * @param null|int $user_id Optional, defaults to current user id
     * @return bool
     */
    public function has_discounted_price( $base_price, $product, $user_id = null ) {

        if ( ! is_object( $product ) ) {
            $product = wc_get_product( $product );
        }

        $has_discounted_price = is_numeric( $this->get_discounted_price( $base_price, $product, $user_id ) );

        if ( ! $has_discounted_price && $product->is_type( 'variable' ) && ( $variations = $product->get_children() ) ) {

            $variations_discounts = array();

            foreach ( $variations as $variation_id ) {

                $variations_discounts[] = $this->has_discounted_price( $base_price, $variation_id, $user_id );
            }

            $has_discounted_price = in_array( true, $variations_discounts, true );
        }

        return $has_discounted_price;
    }


    /**
     * Refresh cart fragments upon member login
     *
     * This is useful if a non-logged in member added items to cart
     * which should have otherwise membership discounts applied
     *
     * @internal
     *
     * @see \WC_Cart::reset()
     *
     * @since 1.6.4
     * @param string $user_login User login name
     * @param \WP_User $user User that just logged in
     */
    public function refresh_cart_upon_member_login( $user_login, $user ) {

        // small "hack" to trigger a refresh in cart contents
        // that will set any membership discounts to products that apply
        if ( $user_login && wc_memberships_is_user_active_member( $user, null, false ) ) {

            $this->reset_cart_session_data();
        }
    }


    /**
     * Reset cart session data
     *
     * @see \WC_Cart::reset() private method
     *
     * @since 1.6.4
     */
    private function reset_cart_session_data() {

        $wc = WC();

        // some very zealous sanity checks here
        if ( $wc && isset( $wc->cart->cart_session_data ) ) {

            $session_data = $wc->cart->cart_session_data;

            if ( ! empty( $session_data ) ) {

                foreach ( $session_data as $key => $default ) {

                    if ( isset( $wc->session->$key ) ) {
                        unset( $wc->session->$key );
                    }
                }
            }

            // WooCommerce core filter
            do_action( 'woocommerce_cart_reset', $wc->cart, true );
        }
    }


    /**
     * Enable price adjustments
     *
     * Calling this method will **enable** Membership adjustments
     * for product prices that have member discounts for logged in members
     *
     * @see \WC_Memberships_Member_Discounts::__construct() docblock for additional notes
     * @see \WC_Memberships_Member_Discounts::enable_price_html_adjustments() which you'll probably want to use too
     *
     * @since 1.3.0
     */
    public function enable_price_adjustments() {

        // apply membership discount to product price
        add_filter( 'woocommerce_get_price',                 array( $this, 'on_get_price' ), 999, 2 );
        add_filter( 'woocommerce_variation_prices_price',    array( $this, 'on_get_price' ), 999, 2 );
        add_filter( 'woocommerce_get_variation_price',       array( $this, 'on_get_variation_price' ), 999, 4 );
        add_filter( 'woocommerce_get_variation_prices_hash', array( $this, 'set_user_variation_prices_hash' ), 999, 2 );
    }


    /**
     * Disable price adjustments
     *
     * Calling this method will **disable** Membership adjustments
     * for product prices that have member discounts for logged in members
     *
     * @see \WC_Memberships_Member_Discounts::__construct() docblock for additional notes
     * @see \WC_Memberships_Member_Discounts::disable_price_html_adjustments() which you'll probably want to use too
     *
     * @since 1.3.0
     */
    public function disable_price_adjustments() {

        // restore price to original amount before membership discount
        remove_filter( 'woocommerce_get_price',                 array( $this, 'on_get_price' ), 999 );
        remove_filter( 'woocommerce_variation_prices_price',    array( $this, 'on_get_price' ), 999 );
        remove_filter( 'woocommerce_get_variation_price',       array( $this, 'on_get_variation_price' ), 999 );
        remove_filter( 'woocommerce_get_variation_prices_hash', array( $this, 'set_user_variation_prices_hash' ), 999 );
    }


    /**
     * Enable price HTML adjustments
     *
     * @see \WC_Memberships_Member_Discounts::__construct() docblock for additional notes
     * @see \WC_Memberships_Member_Discounts::enable_price_adjustments() which you'll probably want to use too
     *
     * @since 1.3.0
     */
    public function enable_price_html_adjustments() {

        // filter the prices to apply member discounts
        add_filter( 'woocommerce_variation_price_html', array( $this, 'on_price_html' ), 999, 2 );
        add_filter( 'woocommerce_get_price_html',       array( $this, 'on_price_html' ), 999, 2 );
    }


    /**
     * Disable price HTML adjustments
     *
     * @see \WC_Memberships_Member_Discounts::__construct() docblock for additional notes
     * @see \WC_Memberships_Member_Discounts::disable_price_adjustments() which you'll probably want to use too
     *
     * @since 1.3.0
     */
    public function disable_price_html_adjustments() {

        // so we can display prices before discount
        remove_filter( 'woocommerce_get_price_html',       array( $this, 'on_price_html' ), 999 );
        remove_filter( 'woocommerce_variation_price_html', array( $this, 'on_price_html' ), 999 );
    }


}