<?php
/**
 * The variation converter: read a variable product, build the option version
 * beside it.
 *
 * The listing argues that five colours by five sizes is twenty-five variations
 * or one option set. Everyone who feels that pain ALREADY HAS the twenty-five,
 * and until now our answer to "what about the ones I have built?" was "build
 * them again by hand". This is that answer.
 *
 * THE RULE THAT SHAPES EVERYTHING HERE: never convert in place. Turning a
 * variable product into a simple one deletes its variations, and existing
 * orders point at those variation ids, so an in-place converter orphans order
 * history and is a one-way door nobody should run on a live catalogue. Instead
 * a NEW DRAFT product is built beside the original, which is never touched, so
 * the merchant compares the two and deletes a draft if they disagree.
 *
 * What carries over, and what cannot, is counted BEFORE anything is written and
 * said out loud in the merchant's own figures. The honest losses:
 *
 *   - A SKU per combination. A simple product has one SKU. Any shop that picks,
 *     packs, reorders or feeds a marketplace by SKU needs to know this before
 *     it converts, not three weeks later.
 *   - Stock per pair needs the plan. Without it the draft carries prices and
 *     photographs but counts nothing.
 *   - Per-variation weight, dimensions, shipping class and download files have
 *     no home on an option choice yet.
 *
 * @package AddOnBoss
 */

defined( 'ABSPATH' ) || exit;

/** The draft this product was rebuilt into, stored on the variable product. */
const ADDON_BOSS_CONVERTED_TO = '_addon_boss_converted_to';

/** The variable product a draft came from, stored on the draft. */
const ADDON_BOSS_CONVERTED_FROM = '_addon_boss_converted_from';

/**
 * Read a variable product into a plan: the sets to build, the price of every
 * pair, what is on the shelf, and what will not survive the trip.
 *
 * Reads only. Nothing here writes, so a merchant can be shown the whole answer
 * before deciding.
 *
 * @param WC_Product|int $product The variable product to read.
 * @return array{} on refusal, or the plan.
 */
function addon_boss_variation_plan( $product ): array {
	if ( ! $product instanceof WC_Product ) {
		$product = function_exists( 'wc_get_product' ) ? wc_get_product( (int) $product ) : null;
	}
	if ( ! $product instanceof WC_Product || ! $product->is_type( 'variable' ) ) {
		return array();
	}

	// Only attributes actually used for variations become sets. A variable
	// product often carries descriptive attributes too (Material, Brand) that
	// no variation varies on; those belong on the product, not in a chooser.
	$axes = array();
	foreach ( $product->get_attributes() as $attr ) {
		if ( ! $attr instanceof WC_Product_Attribute || ! $attr->get_variation() ) {
			continue;
		}
		$slug  = (string) $attr->get_name();
		$terms = array();
		foreach ( $attr->get_options() as $opt ) {
			if ( $attr->is_taxonomy() ) {
				$term = get_term( (int) $opt );
				if ( $term instanceof WP_Term ) {
					$terms[ $term->slug ] = $term->name;
				}
				continue;
			}
			$terms[ sanitize_title( (string) $opt ) ] = (string) $opt;
		}
		if ( $terms ) {
			$axes[ $slug ] = array(
				'label' => wc_attribute_label( $slug, $product ),
				'terms' => $terms,
			);
		}
	}
	if ( ! $axes ) {
		return array();
	}

	// A stable option key per attribute value, so the same colour keeps the
	// same key across every cell and every stock row.
	$keys = array();
	foreach ( $axes as $slug => $axis ) {
		foreach ( array_keys( $axis['terms'] ) as $value ) {
			$k = 'op_' . substr( md5( $slug . '|' . $value ), 0, 10 );
			$keys[ $slug ][ $value ] = $k;
		}
	}

	$cells   = array();
	$stock   = array();
	$prices  = array();
	$images  = 0;
	$skus    = 0;
	$partial = 0;
	$onsale  = 0;
	$parcels = array();
	$total   = 0;

	foreach ( $product->get_children() as $child_id ) {
		$var = wc_get_product( $child_id );
		if ( ! $var instanceof WC_Product_Variation ) {
			continue;
		}
		++$total;

		// A variation may leave an axis "any", which is not a pair and cannot
		// become a priced cell. Counted and reported rather than guessed at.
		$picks = array();
		$whole = true;
		foreach ( array_keys( $axes ) as $slug ) {
			$value = (string) ( $var->get_attribute( $slug ) );
			$value = '' !== $value ? sanitize_title( $value ) : '';
			if ( '' === $value || ! isset( $keys[ $slug ][ $value ] ) ) {
				$whole = false;
				break;
			}
			$picks[ $slug ] = $keys[ $slug ][ $value ];
		}
		if ( ! $whole ) {
			++$partial;
			continue;
		}

		// The REGULAR price, never get_price(): that returns the sale price
		// while a variation is on sale, and a cell map holds one figure, so a
		// sale would become the permanent price and the shop would undercharge
		// for good once the sale ended.
		$price = $var->get_regular_price( 'edit' );
		if ( '' === $price || null === $price ) {
			$price = $var->get_price( 'edit' );
		}
		if ( '' !== $price && null !== $price ) {
			$cells[]  = array( 'picks' => $picks, 'price' => (float) $price );
			$prices[] = (float) $price;
		}
		if ( '' !== (string) $var->get_sale_price( 'edit' ) ) {
			++$onsale;
		}
		if ( $var->managing_stock() && null !== $var->get_stock_quantity() ) {
			$stock[] = array( 'picks' => $picks, 'qty' => (int) $var->get_stock_quantity() );
		}
		// What this pair weighs and measures. A 3XL hoodie is not the same
		// parcel as an XS tee, and a simple product has one of each, so these
		// travel in their own map beside the prices.
		$ship = array( 'picks' => $picks );
		foreach ( array( 'weight', 'length', 'width', 'height' ) as $bb_f ) {
			$getter = 'get_' . $bb_f;
			$val    = (string) $var->$getter( 'edit' );
			if ( '' !== $val ) {
				$ship[ $bb_f ] = $val;
			}
		}
		if ( count( $ship ) > 1 ) {
			$parcels[] = $ship;
		}
		if ( '' !== (string) $var->get_sku() ) {
			++$skus;
		}
		// 'edit', because the view context falls back to the PARENT image: every
		// variation then claims a photograph and the receipt promises pictures
		// that do not exist. Only a variation's own photo counts.
		if ( $var->get_image_id( 'edit' ) ) {
			++$images;
		}
	}

	// The options the merchant had already attached ON TOP of the variations.
	// AddOnBoss works with variable products as they are, so a shop may have
	// been running fields and sets over this product for months; they are part
	// of what is being copied, and losing them would punish exactly the
	// merchants who used the plugin most.
	$attached = array();
	foreach ( (array) get_post_meta( (int) $product->get_id(), '_bundle_boss_product_options', true ) as $bb_row ) {
		if ( is_array( $bb_row ) ) {
			$attached[] = $bb_row;
		}
	}

	// Reviews are comments on the post, so a copy does not bring them. Counted
	// directly rather than through WooCommerce's cached meta, which lags a
	// fresh review by one sync.
	$reviews = (int) get_comments(
		array(
			'post_id' => (int) $product->get_id(),
			'type'    => 'review',
			'status'  => 'approve',
			'count'   => true,
		)
	);

	return array(
		'source' => (int) $product->get_id(),
		'name'   => (string) $product->get_name(),
		'axes'   => $axes,
		'keys'   => $keys,
		'base'   => $prices ? (float) min( $prices ) : 0.0,
		'cells'  => $cells,
		'stock'  => $stock,
		'parcels' => $parcels,
		'attached' => $attached,
		'counts' => array(
			'variations' => $total,
			'priced'     => count( $cells ),
			'stocked'    => count( $stock ),
			'skus'       => $skus,
			'images'     => $images,
			'partial'    => $partial,
			'onsale'     => $onsale,
			'parcels'    => count( $parcels ),
			'axes'       => count( $axes ),
			'attached'   => count( $attached ),
			'reviews'    => $reviews,
		),
	);
}

/**
 * The plan as a receipt: one line per thing that happens, including the things
 * that do not. Every figure is the merchant's own.
 *
 * A receipt that only lists the wins is an advertisement. The losses are the
 * half a merchant needs before they decide, so they are not softened and they
 * are not left to be discovered later.
 *
 * @return array<int,array{kind:string,text:string}> kind is 'keep' or 'lose'.
 */
function addon_boss_variation_plan_notes( array $plan ): array {
	if ( ! $plan ) {
		return array();
	}
	$c     = $plan['counts'];
	$notes = array();

	// One count only: a second count in the same sentence cannot share the
	// plural switch, and "across 1 choices" shipped that way. The axes show
	// themselves as the set rows directly above this receipt.
	$notes[] = array(
		'kind' => 'keep',
		'text' => sprintf(
			/* translators: %s: number of variations */
			_n(
				'%s variation becomes option sets on one product.',
				'%s variations become option sets on one product.',
				$c['variations'],
				'addon-boss'
			),
			number_format_i18n( $c['variations'] )
		),
	);

	// Two true sentences, not one hedged one. A build that reads the pair map
	// charges each combination its exact figure; a build that does not charges
	// the choices' own extra charges, which the converter now fills in. Saying
	// "each pair keeping its own figure" on a build that cannot do it would be
	// the plugin telling a merchant their prices are right when they are close.
	// The test is the file, not the plan: the pair map is read wherever its
	// file is on disk, licence or not, so a lapse never changes a live charge.
	//
	// Extra charges add up, and a supplier's price list often does not: 3XL
	// costing more in Black than in White is ordinary. A build that cannot read
	// the pair map charges such a pair its choices added together, which is a
	// different figure from the one the shop set. Those pairs are counted out
	// of the carry-over line and named in a line of their own, so the two
	// figures add up to the prices read instead of claiming all of them.
	$exact  = function_exists( 'addon_boss_combo_price_for' );
	$uneven = $exact ? 0 : addon_boss_variation_uneven_pairs( $plan );
	$notes[] = array(
		'kind' => 'keep',
		'text' => $exact
			? sprintf(
				/* translators: 1: variations carrying a price, 2: variations in total */
				__( '%1$s of %2$s prices carry over, each pair keeping its own figure.', 'addon-boss' ),
				number_format_i18n( $c['priced'] ),
				number_format_i18n( $c['variations'] )
			)
			: sprintf(
				/* translators: 1: prices the choices' extra charges reproduce exactly, 2: variations in total */
				__( '%1$s of %2$s prices carry over as the extra charge on each choice.', 'addon-boss' ),
				number_format_i18n( max( 0, (int) $c['priced'] - $uneven ) ),
				number_format_i18n( $c['variations'] )
			),
	);

	if ( $uneven > 0 ) {
		$notes[] = array(
			'kind' => 'lose',
			'text' => sprintf(
				/* translators: %s: number of size-and-colour pairs whose price will change */
				_n(
					"%s pair will cost a different amount after the rebuild. This build adds each choice's extra charge together, and that pair was not priced that way.",
					"%s pairs will cost a different amount after the rebuild. This build adds each choice's extra charge together, and those pairs were not priced that way.",
					$uneven,
					'addon-boss'
				),
				number_format_i18n( $uneven )
			),
		);
	}

	if ( $c['stocked'] > 0 ) {
		$notes[] = addon_boss_engine_can( 'option-stock' )
			? array(
				'kind' => 'keep',
				'text' => sprintf(
					/* translators: %s: number of variations holding a stock figure */
					__( '%s stock figures carry over, one for each pair.', 'addon-boss' ),
					number_format_i18n( $c['stocked'] )
				),
			)
			: array(
				'kind' => 'lose',
				'text' => sprintf(
					/* translators: %s: number of variations holding a stock figure */
					__( '%s stock figures cannot carry over. This build counts stock on the product, not on a single choice, so the draft prices every pair but counts none of them.', 'addon-boss' ),
					number_format_i18n( $c['stocked'] )
				),
			);
	}

	// Counted from the photographs the build will place, not from variations
	// that wear one: four variations can carry two pictures, and a picture all
	// of them share stays the product's own photograph. The picture following
	// the choice is a separate behaviour that only some builds have, so it is
	// promised only where it is kept. Every build shows a choice's photograph
	// on the choice itself, because a set whose choices carry pictures draws
	// them as photo cards.
	$photos = count( addon_boss_variation_choice_photos( $plan ) );
	if ( $photos > 0 ) {
		$notes[] = array(
			'kind' => 'keep',
			'text' => addon_boss_engine_can( 'option-photos' )
				? sprintf(
					/* translators: %s: number of choices that will carry a photograph */
					_n(
						'%s photograph carries over, so the picture still follows the choice.',
						'%s photographs carry over, so the picture still follows the choice.',
						$photos,
						'addon-boss'
					),
					number_format_i18n( $photos )
				)
				: sprintf(
					/* translators: %s: number of choices that will carry a photograph */
					_n(
						'%s photograph carries over, shown on its choice.',
						'%s photographs carry over, each shown on its choice.',
						$photos,
						'addon-boss'
					),
					number_format_i18n( $photos )
				),
		);
	}

	if ( ! empty( $c['parcels'] ) ) {
		$notes[] = array(
			'kind' => 'keep',
			'text' => sprintf(
				/* translators: %s: number of variations carrying a weight or dimensions */
				__( '%s weights and dimensions carry over, so shipping is charged on the pair the shopper picked.', 'addon-boss' ),
				number_format_i18n( $c['parcels'] )
			),
		);
	}

	if ( ! empty( $c['attached'] ) ) {
		$notes[] = array(
			'kind' => 'keep',
			'text' => sprintf(
				/* translators: %s: number of option sets and fields already attached to this product */
				_n(
					'%s option set or field already on this product carries over.',
					'%s option sets and fields already on this product carry over.',
					$c['attached'],
					'addon-boss'
				),
				number_format_i18n( $c['attached'] )
			),
		);
	}

	if ( ! empty( $c['onsale'] ) ) {
		$notes[] = array(
			'kind' => 'lose',
			'text' => sprintf(
				/* translators: %s: number of variations currently on sale */
				__( '%s sale prices cannot carry over. A pair holds one figure, so the full price is kept and the sale would have become permanent.', 'addon-boss' ),
				number_format_i18n( $c['onsale'] )
			),
		);
	}

	if ( $c['skus'] > 0 ) {
		$notes[] = array(
			'kind' => 'lose',
			'text' => sprintf(
				/* translators: %s: number of variations carrying their own SKU */
				__( '%s SKUs cannot carry over. A product with options has one SKU, so a shop that works from the code of each combination should stay with variations.', 'addon-boss' ),
				number_format_i18n( $c['skus'] )
			),
		);
	}

	if ( ! empty( $c['reviews'] ) ) {
		$notes[] = array(
			'kind' => 'lose',
			'text' => sprintf(
				/* translators: %s: number of approved reviews on the variable product */
				_n(
					'%s review does not copy. It stays with the original until the copy takes its place, which brings it across.',
					'%s reviews do not copy. They stay with the original until the copy takes its place, which brings them across.',
					$c['reviews'],
					'addon-boss'
				),
				number_format_i18n( $c['reviews'] )
			),
		);
	}

	if ( $c['partial'] > 0 ) {
		$notes[] = array(
			'kind' => 'lose',
			'text' => sprintf(
				/* translators: %s: number of variations that leave a choice as "any" */
				__( '%s variations leave a choice as "any". These are skipped.', 'addon-boss' ),
				number_format_i18n( $c['partial'] )
			),
		);
	}

	$notes[] = array(
		'kind' => 'keep',
		'text' => __( 'Your variable product is not touched. This makes a draft beside it.', 'addon-boss' ),
	);

	return $notes;
}

/**
 * What each choice adds on its own, over the cheapest combination.
 *
 * The shape a supplier bridge already writes and the pair map already expects:
 * every axis but one held at its cheapest choice, so the deltas sum to the true
 * price wherever the grid is additive. Where it is not, the pair map carries the
 * exact figure and a build that can read it re-cuts these to match.
 *
 * This is what a build with no per-pair pricing charges from, so it is the
 * difference between a converted 3XL selling for its own price and selling for
 * the cheapest variation's.
 *
 * @param array $plan From addon_boss_variation_plan().
 * @return array<string,array<string,float>> axis slug => choice key => delta.
 */
function addon_boss_variation_choice_deltas( array $plan ): array {
	$cells = (array) ( $plan['cells'] ?? array() );
	if ( ! $cells ) {
		return array();
	}
	$base = (float) ( $plan['base'] ?? 0.0 );

	// The cheapest combination: the one the base price already covers.
	$cheapest = null;
	foreach ( $cells as $cell ) {
		if ( null === $cheapest || (float) $cell['price'] < (float) $cheapest['price'] ) {
			$cheapest = $cell;
		}
	}
	$anchor_picks = (array) ( $cheapest['picks'] ?? array() );

	$by_key = array();
	foreach ( $cells as $cell ) {
		$picks = (array) $cell['picks'];
		ksort( $picks );
		$by_key[ (string) wp_json_encode( $picks ) ] = (float) $cell['price'];
	}

	$out = array();
	foreach ( (array) ( $plan['axes'] ?? array() ) as $slug => $axis ) {
		foreach ( array_keys( (array) $axis['terms'] ) as $value ) {
			$key = $plan['keys'][ $slug ][ $value ] ?? '';
			if ( '' === (string) $key ) {
				continue;
			}
			// This choice, everything else at its cheapest. A cell's picks are
			// keyed by the generated option KEY, not the raw attribute value.
			$picks          = $anchor_picks;
			$picks[ $slug ] = $key;
			ksort( $picks );
			$price = $by_key[ (string) wp_json_encode( $picks ) ] ?? null;

			if ( null === $price ) {
				// That exact combination is not sold. The cheapest cell this
				// choice appears in is the honest answer: it never charges for
				// a step the shopper did not take.
				foreach ( $cells as $cell ) {
					if ( ( $cell['picks'][ $slug ] ?? null ) === $key
						&& ( null === $price || (float) $cell['price'] < $price ) ) {
						$price = (float) $cell['price'];
					}
				}
			}
			if ( null !== $price ) {
				$out[ $slug ][ $key ] = addon_boss_round_money( (float) $price - $base, 2 );
			}
		}
	}
	return $out;
}

/**
 * How many priced pairs a build without per-pair pricing would charge a
 * different figure: the pairs whose own price is not the base plus the extra
 * charge of each of their choices.
 *
 * Reads the same deltas the build writes, so the count is exactly the pairs
 * that will change, not an estimate of them.
 *
 * @param array $plan From addon_boss_variation_plan().
 */
function addon_boss_variation_uneven_pairs( array $plan ): int {
	$deltas = addon_boss_variation_choice_deltas( $plan );
	$base   = (float) ( $plan['base'] ?? 0.0 );
	$n      = 0;
	foreach ( (array) ( $plan['cells'] ?? array() ) as $cell ) {
		$charged = $base;
		foreach ( (array) $cell['picks'] as $slug => $key ) {
			$charged += (float) ( $deltas[ $slug ][ $key ] ?? 0.0 );
		}
		if ( abs( addon_boss_round_money( $charged, 2 ) - addon_boss_round_money( (float) $cell['price'], 2 ) ) >= 0.005 ) {
			++$n;
		}
	}
	return $n;
}

/**
 * The photograph each choice will wear: choice key => attachment id.
 *
 * Read with 'edit', because the view context falls back to the parent image
 * and every choice on every axis would inherit the same picture. And a photo
 * only follows an axis it actually DISTINGUISHES: the shot on the black/S
 * variation belongs to Black, not to S, so an axis keeps its map only when at
 * least two of its choices ended up with different pictures. First one wins
 * within an axis: a colour is one colour however many sizes it comes in.
 *
 * The build reads it to place the pictures and the receipt reads it to count
 * them, so the two cannot disagree. Counting variations instead promised four
 * photographs where the build placed two, and promised pictures to a product
 * whose variations all share one, which the build rightly leaves on the
 * product rather than on any choice.
 *
 * @param array $plan From addon_boss_variation_plan().
 * @return array<string,int>
 */
function addon_boss_variation_choice_photos( array $plan ): array {
	$source = ! empty( $plan['source'] ) ? wc_get_product( (int) $plan['source'] ) : null;
	if ( ! $source instanceof WC_Product ) {
		return array();
	}
	$axis_photos = array();
	foreach ( $source->get_children() as $child_id ) {
		$var = wc_get_product( $child_id );
		if ( ! $var instanceof WC_Product_Variation ) {
			continue;
		}
		$img = (int) $var->get_image_id( 'edit' );
		if ( $img < 1 ) {
			continue;
		}
		foreach ( array_keys( (array) ( $plan['axes'] ?? array() ) ) as $slug ) {
			$value = sanitize_title( (string) $var->get_attribute( $slug ) );
			$key   = $plan['keys'][ $slug ][ $value ] ?? '';
			if ( '' !== $key && ! isset( $axis_photos[ $slug ][ $key ] ) ) {
				$axis_photos[ $slug ][ $key ] = $img;
			}
		}
	}
	$photos = array();
	foreach ( $axis_photos as $bb_map ) {
		if ( count( array_unique( $bb_map ) ) >= 2 ) {
			$photos += $bb_map;
		}
	}
	return $photos;
}

/**
 * Build the plan: option sets, then a draft product carrying them.
 *
 * The original is read and never written. The draft is left as a draft on
 * purpose, so nothing reaches a shopper until the merchant has looked at it.
 *
 * @return int The new draft product id, or 0 when nothing could be built.
 */
function addon_boss_variation_build( array $plan ): int {
	if ( ! $plan || ! function_exists( 'addon_boss_save_option_set' ) ) {
		return 0;
	}
	$source = wc_get_product( (int) $plan['source'] );
	if ( ! $source instanceof WC_Product ) {
		return 0;
	}

	// Which photograph belongs to which choice: the same rule the receipt
	// counts by, so the receipt never promises a picture the build drops.
	$photos = addon_boss_variation_choice_photos( $plan );

	// What each choice adds on its own, worked out the way a supplier bridge
	// writes it: every other choice held at its cheapest, so the figures add up
	// to the true price wherever the grid is additive.
	//
	// These are NOT redundant with the cell map below. A build that can charge
	// per pair RE-CUTS these so their sum is the cell exactly; a build that
	// cannot falls back to them and charges additively. Leaving them at zero
	// meant a free shop charged the cheapest variation's price for every
	// combination, so a 3XL that sold for 6.20 as a variation would have gone
	// out at 3.55 forever.
	$deltas = addon_boss_variation_choice_deltas( $plan );

	// One set per varying attribute.
	$set_ids = array();
	foreach ( $plan['axes'] as $slug => $axis ) {
		$options = array();
		foreach ( $axis['terms'] as $value => $label ) {
			$key       = $plan['keys'][ $slug ][ $value ];
			$options[] = array(
				'key'      => $key,
				'label'    => $label,
				'swatch'   => '',
				'swatch2'  => '',
				'desc'     => '',
				'image_id' => (int) ( $photos[ $key ] ?? 0 ),
				'delta'    => (float) ( $deltas[ $slug ][ $key ] ?? 0.0 ),
				'dims'     => array( 0.0, 0.0, 0.0 ),
			);
		}
		$set_ids[ $slug ] = addon_boss_save_option_set(
			array(
				'name'    => $axis['label'],
				'kind'    => 'choices',
				'options' => $options,
			)
		);
	}

	// The draft, built from the original rather than in place of it.
	$draft = new WC_Product_Simple();
	$draft->set_name(
		sprintf(
			/* translators: %s: the name of the variable product this was copied from */
			__( '%s (Copy)', 'addon-boss' ),
			$plan['name']
		)
	);
	$draft->set_status( 'draft' );
	$draft->set_description( $source->get_description() );
	$draft->set_short_description( $source->get_short_description() );
	$draft->set_category_ids( $source->get_category_ids() );
	$draft->set_image_id( $source->get_image_id() );
	$draft->set_gallery_image_ids( $source->get_gallery_image_ids() );
	$draft->set_tax_status( $source->get_tax_status() );
	$draft->set_tax_class( $source->get_tax_class() );

	// Everything else a simple product can hold. WooCommerce's own Duplicate
	// clones the whole product and then clears a short list; copying a
	// hand-picked few instead is how a shipping class or a purchase note
	// disappears without anybody noticing. The reset list below matches Woo's.
	$draft->set_tag_ids( $source->get_tag_ids() );
	$draft->set_featured( $source->get_featured() );
	$draft->set_catalog_visibility( $source->get_catalog_visibility() );
	$draft->set_menu_order( $source->get_menu_order() );
	$draft->set_reviews_allowed( $source->get_reviews_allowed() );
	$draft->set_purchase_note( $source->get_purchase_note() );
	$draft->set_cross_sell_ids( $source->get_cross_sell_ids() );
	$draft->set_upsell_ids( $source->get_upsell_ids() );
	$draft->set_weight( $source->get_weight() );
	$draft->set_length( $source->get_length() );
	$draft->set_width( $source->get_width() );
	$draft->set_height( $source->get_height() );
	$draft->set_shipping_class_id( $source->get_shipping_class_id() );

	// The attributes a variation never varied on (Material, Brand) still
	// describe the product, so they travel as ordinary product attributes.
	// The varying ones are becoming option sets and would only be noise here.
	$keep_attrs = array();
	foreach ( $source->get_attributes() as $attr_key => $attr ) {
		if ( $attr instanceof WC_Product_Attribute && ! $attr->get_variation() ) {
			$keep_attrs[ $attr_key ] = $attr;
		}
	}
	$draft->set_attributes( $keep_attrs );

	$draft->set_regular_price( (string) $plan['base'] );
	$draft->set_price( (string) $plan['base'] );
	$id = (int) $draft->save();
	if ( $id < 1 ) {
		return 0;
	}

	$config = array();
	foreach ( $set_ids as $sid ) {
		if ( '' !== (string) $sid ) {
			// Explicitly empty override maps, so the stored row has the same
			// shape the admin form writes and nothing downstream has to guess.
			$config[] = array(
				'type'     => 'set',
				'set'      => $sid,
				'required' => true,
				'deltas'   => array(),
				'images'   => array(),
			);
		}
	}
	// What was already attached on top of the variations follows the converted
	// sets, mirroring the old page's order: the variation pickers came first,
	// the add-ons after them.
	foreach ( (array) ( $plan['attached'] ?? array() ) as $bb_row ) {
		if ( is_array( $bb_row ) ) {
			$config[] = $bb_row;
		}
	}
	$draft->update_meta_data( '_bundle_boss_product_options', $config );

	// Every pair's own price, in the ONE currency the cell map speaks: a cell
	// is the pair's price LESS THE BASE, never the price itself. The base is
	// already on the product and the resolve boundary adds the cells on top of
	// it, so a whole price written here is charged twice over: a £6.20 shirt
	// went out at £9.75, with the page still saying £5.89. The sets are sorted
	// because the key spelling is a convention every writer shares.
	$sets = array_values( array_filter( $set_ids ) );
	sort( $sets );
	$rows = array();
	foreach ( $plan['cells'] as $cell ) {
		$picks = array();
		foreach ( $plan['axes'] as $slug => $ignored ) {
			$sid = $set_ids[ $slug ] ?? '';
			if ( '' !== (string) $sid && isset( $cell['picks'][ $slug ] ) ) {
				$picks[ $sid ] = $cell['picks'][ $slug ];
			}
		}
		if ( count( $picks ) === count( $sets ) ) {
			$rows[] = array(
				'picks' => $picks,
				'delta' => round( (float) $cell['price'] - (float) $plan['base'], 4 ),
			);
		}
	}
	if ( $rows && function_exists( 'addon_boss_combo_prices_put' ) ) {
		// The sanctioned writer where it exists: it floors a negative and drops
		// a cell it cannot key, so the converter keeps no second spelling of
		// either rule. It saves the product itself.
		$draft->save();
		addon_boss_combo_prices_put( $id, $sets, $rows );
		$draft = wc_get_product( $id );
	} elseif ( $rows && function_exists( 'addon_boss_combo_price_key' ) ) {
		// A free build writes the map too. It cannot READ it — per-pair pricing
		// is Pro — but the figures are the merchant's own, and throwing them
		// away here would mean re-converting the day they upgrade.
		$cells = array();
		foreach ( $rows as $row ) {
			$key = addon_boss_combo_price_key( $row['picks'], $sets );
			if ( '' !== $key ) {
				$cells[ $key ] = max( 0.0, (float) $row['delta'] );
			}
		}
		if ( $cells ) {
			$draft->update_meta_data( '_addon_boss_combo_prices', array( 'sets' => $sets, 'cells' => $cells ) );
		}
		$draft->save();
	} else {
		$draft->save();
	}

	// What each pair weighs and measures, so a courier quotes the right parcel
	// for a 3XL rather than the product's single figure for every size.
	if ( ! empty( $plan['parcels'] ) && function_exists( 'addon_boss_combo_ship_put' ) ) {
		$rows = array();
		foreach ( $plan['parcels'] as $row ) {
			$picks = array();
			foreach ( $plan['axes'] as $slug => $ignored ) {
				$sid = $set_ids[ $slug ] ?? '';
				if ( '' !== (string) $sid && isset( $row['picks'][ $slug ] ) ) {
					$picks[ $sid ] = $row['picks'][ $slug ];
				}
			}
			if ( count( $picks ) === count( $sets ) ) {
				$rows[] = array_merge( $row, array( 'picks' => $picks ) );
			}
		}
		if ( $rows ) {
			addon_boss_combo_ship_put( $id, $sets, $rows );
		}
	}

	// What is on the shelf, pair by pair. Silently absent without the plan, the
	// way every other Pro capability is: the merchant's figures are not written
	// somewhere they would rot, they simply stay on the original.
	if ( $plan['stock'] && function_exists( 'addon_boss_combo_stock_put' ) && addon_boss_engine_can( 'option-stock' ) ) {
		$pairs = array();
		$left  = 0;
		foreach ( $plan['stock'] as $row ) {
			$picks = array();
			foreach ( $plan['axes'] as $slug => $ignored ) {
				$sid = $set_ids[ $slug ] ?? '';
				if ( '' !== (string) $sid && isset( $row['picks'][ $slug ] ) ) {
					$picks[ $sid ] = $row['picks'][ $slug ];
				}
			}
			if ( count( $picks ) === count( $sets ) ) {
				$pairs[] = array( 'picks' => $picks, 'qty' => (int) $row['qty'] );
				$left   += (int) $row['qty'];
			}
		}
		if ( $pairs ) {
			addon_boss_combo_stock_put( $id, $sets, $pairs );
			$fresh = wc_get_product( $id );
			if ( $fresh instanceof WC_Product ) {
				$fresh->set_manage_stock( true );
				$fresh->set_stock_quantity( $left );
				$fresh->set_stock_status( $left > 0 ? 'instock' : 'outofstock' );
				$fresh->save();
			}
		}
	}

	// Both ends of the trip remember each other, so a second visit to the
	// variable product offers the draft that exists rather than quietly
	// building a second one and a second copy of every set with it.
	$source->update_meta_data( ADDON_BOSS_CONVERTED_TO, $id );
	$source->save();
	update_post_meta( $id, ADDON_BOSS_CONVERTED_FROM, (int) $plan['source'] );

	// The count on the checklist is now wrong by one product; ask fresh next time.
	delete_transient( 'addon_boss_variation_load' );

	return $id;
}

/**
 * The draft already built from this product, or 0.
 *
 * Heals itself: a merchant who looked at a draft, disagreed and binned it gets
 * the offer back rather than a link to a post that is not there.
 */
function addon_boss_variation_built_draft( int $product_id ): int {
	$draft = (int) get_post_meta( $product_id, ADDON_BOSS_CONVERTED_TO, true );
	if ( $draft < 1 ) {
		return 0;
	}
	$post = get_post( $draft );
	if ( ! $post instanceof WP_Post || 'trash' === $post->post_status ) {
		delete_post_meta( $product_id, ADDON_BOSS_CONVERTED_TO );
		return 0;
	}
	return $draft;
}

// ---------------------------------------------------------------------
// The offer itself. It lives INSIDE the Product options tab, below the
// attach UI: AddOnBoss works on top of variations without converting
// anything, so the tab leads with that and the rebuild is the card
// underneath, never the room. Two more doors lead here: a row action on
// variable products in the list, and the landing checklist's count line.
// ---------------------------------------------------------------------

/** Who may do this: the same capability that may edit the product in the first place. */
function addon_boss_variation_convert_allowed( int $product_id ): bool {
	return current_user_can( 'edit_post', $product_id );
}

/**
 * A row action on variable products in the list: the offer sits on the thing
 * itself. It opens the product with the card in view and builds nothing.
 */
add_filter( 'post_row_actions', 'addon_boss_variation_row_action', 10, 2 );
function addon_boss_variation_row_action( array $actions, $post ): array {
	if ( ! $post instanceof WP_Post || 'product' !== $post->post_type || 'trash' === $post->post_status || ! addon_boss_variation_convert_allowed( (int) $post->ID ) ) {
		return $actions;
	}
	$product = wc_get_product( $post->ID );
	if ( ! $product instanceof WC_Product || ! $product->is_type( 'variable' ) ) {
		return $actions;
	}
	$actions['addon_boss_rebuild'] = '<a href="' . esc_url( add_query_arg( 'bb_rebuild', '1', (string) get_edit_post_link( $post->ID, 'url' ) ) ) . '">'
		. esc_html__( 'Options instead of variations', 'addon-boss' ) . '</a>';
	return $actions;
}

/** The offer card, at the bottom of the Product options tab on a variable product. */
add_action( 'addon_boss_options_panel_after', 'addon_boss_variation_offer_card' );
function addon_boss_variation_offer_card( $product ): void {
	if ( ! $product instanceof WC_Product || ! $product->is_type( 'variable' ) || ! addon_boss_variation_convert_allowed( (int) $product->get_id() ) ) {
		return;
	}
	$plan  = addon_boss_variation_plan( (int) $product->get_id() );
	$notes = addon_boss_variation_plan_notes( $plan );
	if ( ! $notes ) {
		return; // Nothing varies, so there is nothing to offer.
	}

	// The not-touched promise prints beside the button, where the hesitation
	// happens, rather than as one more receipt line.
	$safe  = __( 'Your variable product is not touched. This makes a draft beside it.', 'addon-boss' );
	$keeps = array();
	$loses = array();
	foreach ( $notes as $note ) {
		if ( $note['text'] === $safe ) {
			continue;
		}
		if ( 'keep' === $note['kind'] ) {
			$keeps[] = $note['text'];
		} else {
			$loses[] = $note['text'];
		}
	}

	echo '<div class="bb-vc-card" id="addon-boss-variation-convert">';
	echo '<div class="bb-vc-head"><b>' . esc_html__( 'Options instead of variations', 'addon-boss' ) . '</b><span>'
		. esc_html__( 'Rather run this as one product? A rebuild makes a draft beside this one.', 'addon-boss' ) . '</span></div>';

	// The sets the rebuild would make, with the shop's own choice names on
	// them, because "2 option sets" is an argument and "Colour: Black, Navy,
	// Red" is their Tuesday.
	foreach ( $plan['axes'] as $axis ) {
		echo '<div class="bb-vc-setrow"><span class="bb-vc-nm">' . esc_html( (string) $axis['label'] ) . '</span><span class="bb-vc-opts">';
		$shown = 0;
		foreach ( (array) $axis['terms'] as $label ) {
			if ( $shown >= 8 ) {
				break;
			}
			echo '<span class="bb-vc-opt">' . esc_html( (string) $label ) . '</span>';
			$shown++;
		}
		$more = count( (array) $axis['terms'] ) - $shown;
		if ( $more > 0 ) {
			echo '<span class="bb-vc-opt">' . esc_html( sprintf(
				/* translators: %s: how many more there are beyond the ones shown */
				__( '+%s more', 'addon-boss' ),
				number_format_i18n( $more )
			) ) . '</span>';
		}
		echo '</span></div>';
	}

	// A heading with nothing under it reads as a list that failed to load. A
	// simple shop often loses nothing at all, so each column only appears when
	// it has something to say, and one column alone takes the full width.
	echo '<div class="bb-vc-rail' . ( $keeps && $loses ? '' : ' is-single' ) . '">';
	if ( $keeps ) {
		echo '<div><h4>' . esc_html__( 'Carries over', 'addon-boss' ) . '</h4><ul class="bb-vc-keeps">';
		foreach ( $keeps as $bb_t ) {
			echo '<li>' . esc_html( $bb_t ) . '</li>';
		}
		echo '</ul></div>';
	}
	if ( $loses ) {
		echo '<div><h4>' . esc_html__( 'Does not', 'addon-boss' ) . '</h4><ul class="bb-vc-loses">';
		foreach ( $loses as $bb_t ) {
			echo '<li>' . esc_html( $bb_t ) . '</li>';
		}
		echo '</ul></div>';
	}
	echo '</div>';

	$url = wp_nonce_url(
		admin_url( 'admin-post.php?action=addon_boss_variation_convert&product=' . (int) $product->get_id() ),
		'addon_boss_variation_convert_' . (int) $product->get_id()
	);

	// Already done once. Lead with the draft rather than the offer: building
	// again would make a second draft AND a second copy of every set, which is
	// how a library fills with duplicate Colours nobody meant to create.
	$built = addon_boss_variation_built_draft( (int) $product->get_id() );
	echo '<div class="bb-vc-acts">';
	if ( empty( $plan['counts']['priced'] ) ) {
		// Every pair fell out of the plan (all "any" rows, or nothing priced).
		// Offering the button anyway would build a draft that charges nothing.
		echo '<span class="bb-vc-stop">' . esc_html__( 'There is nothing to build yet: no combination carries a price of its own. The lines above say why.', 'addon-boss' ) . '</span>';
	} elseif ( $built > 0 ) {
		echo '<a class="button bb-vc-quiet" href="' . esc_url( (string) get_edit_post_link( $built, 'url' ) ) . '">' . esc_html__( 'Open the copy', 'addon-boss' ) . '</a>';
		echo '<a class="bb-vc-again" href="' . esc_url( $url ) . '">' . esc_html__( 'Duplicate it again', 'addon-boss' ) . '</a>';
		echo '<span class="bb-vc-safe">' . esc_html__( 'This product already has an option-set copy.', 'addon-boss' ) . '</span>';
	} else {
		// The ask before the build. A stray draft and a stray copy of every set
		// is a tidy-up job nobody chose, and this button sits under a panel
		// people scroll through, so a mis-click is the likely way to get one.
		printf(
			'<a class="button bb-cta bb-vc-go" href="%1$s" data-bb-busy="%2$s" data-bb-ask="%3$s" data-bb-yes="%4$s">%5$s</a>',
			esc_url( $url ),
			esc_attr__( 'Duplicating…', 'addon-boss' ),
			esc_attr( sprintf(
				/* translators: %s: the variable product a draft would be built from */
				__( 'Build a draft copy of %s with option sets?', 'addon-boss' ),
				$product->get_name()
			) ),
			esc_attr__( 'Build the draft', 'addon-boss' ),
			esc_html__( 'Duplicate with option sets', 'addon-boss' )
		);
		echo '<span class="bb-vc-safe">' . esc_html( $safe ) . '</span>';
	}
	echo '</div>';
	echo '</div>';

	// The ask, and then the busy state the ask hands over to.
	addon_boss_variation_confirm_js();
	// The row action's landing: WooCommerce's tabs are driven by its own ready
	// handler, so the switch runs from ready too, after the tab exists. The
	// scroll is window-only: scrollIntoView walks every scrollable ancestor,
	// and WooCommerce's .panel-wrap is overflow:hidden yet programmatically
	// scrollable, so it shifted the tab rail out of view with no scrollbar
	// to bring it back and the whole box read as broken.
	wp_print_inline_script_tag(
		'jQuery(function(){if(!/[?&]bb_rebuild=1/.test(window.location.search)){return;}' .
		'var t=document.querySelector(\'.product_data_tabs a[href="#bundle_boss_options_panel"]\');if(t){t.click();}' .
		'var c=document.getElementById("addon-boss-variation-convert");if(c){var r=c.getBoundingClientRect();' .
		'window.scrollTo({top:Math.max(0,r.top+window.pageYOffset-Math.max(80,(window.innerHeight-r.height)/2))});}});'
	);
}

// ---------------------------------------------------------------------
// After the build: the check. The draft's own tab opens with real pairs
// to spot-check, then offers the finish as one confirmed move.
// ---------------------------------------------------------------------

/** One dismissal, this product only: the card never returns on it. */
const ADDON_BOSS_CHECK_DISMISSED = '_addon_boss_check_dismissed';

/**
 * Three pairs from the stored map: cheapest, one from the middle, dearest.
 * Checking the ends catches a wrong step faster than checking neighbours.
 *
 * @return array<int,array{label:string,price:float}>
 */
function addon_boss_variation_check_rows( int $draft_id ): array {
	$map = get_post_meta( $draft_id, '_addon_boss_combo_prices', true );
	if ( ! is_array( $map ) || empty( $map['cells'] ) || ! is_array( $map['cells'] ) ) {
		return array();
	}
	// A cell is the pair's charge OVER the base, so the receipt adds the base
	// back to print the figure the shopper actually sees. Reading the cell as
	// a whole price here would show the right number for the wrong reason and
	// hide the day the convention drifts.
	$bb_prod = function_exists( 'wc_get_product' ) ? wc_get_product( $draft_id ) : null;
	$bb_base = $bb_prod instanceof WC_Product ? (float) $bb_prod->get_regular_price() : 0.0;

	$sets   = function_exists( 'addon_boss_option_sets' ) ? addon_boss_option_sets() : array();
	$labels = array();
	foreach ( (array) ( $map['sets'] ?? array() ) as $sid ) {
		foreach ( (array) ( $sets[ $sid ]['options'] ?? array() ) as $opt ) {
			if ( isset( $opt['key'], $opt['label'] ) ) {
				$labels[ $sid . '::' . $opt['key'] ] = (string) $opt['label'];
			}
		}
	}
	// A stored key sorts its set ids so one pair always keys the same way. The
	// merchant reads this card against their own variations screen, where the
	// sets sit in the order they arranged them, so the label follows that order
	// rather than the storage one. Otherwise a Colour-then-Size product checks
	// out as "M · Black" and every row costs them a mental flip.
	$order = array();
	foreach ( (array) get_post_meta( $draft_id, ADDON_BOSS_PRODUCT_OPTIONS_META, true ) as $bb_row ) {
		if ( 'set' === ( $bb_row['type'] ?? '' ) && ! empty( $bb_row['set'] ) ) {
			$order[] = (string) $bb_row['set'];
		}
	}

	$cells = array();
	foreach ( $map['cells'] as $key => $price ) {
		$parts = array();
		foreach ( explode( '|', (string) $key ) as $piece ) {
			if ( ! isset( $labels[ $piece ] ) ) {
				continue;
			}
			$rank           = array_search( (string) strstr( $piece, '::', true ), $order, true );
			$parts[ false === $rank ? 900 + count( $parts ) : $rank ] = $labels[ $piece ];
		}
		if ( ! $parts ) {
			continue;
		}
		ksort( $parts );
		$cells[] = array(
			'label' => implode( ' · ', $parts ),
			'price' => addon_boss_round_money( $bb_base + (float) $price, 2 ),
		);
	}
	if ( ! $cells ) {
		return array();
	}
	usort( $cells, static fn( $a, $b ) => $a['price'] <=> $b['price'] );
	$rows = array();
	foreach ( array_unique( array( 0, intdiv( count( $cells ), 2 ), count( $cells ) - 1 ) ) as $i ) {
		$rows[] = $cells[ $i ];
	}
	return $rows;
}

/**
 * Whether the product a draft was built from counted stock on any variation.
 *
 * The same test the plan uses to gather stock rows, so the check card and the
 * receipt agree on whether there was stock to speak about.
 */
function addon_boss_variation_source_held_stock( int $draft_id ): bool {
	$source = wc_get_product( (int) get_post_meta( $draft_id, ADDON_BOSS_CONVERTED_FROM, true ) );
	if ( ! $source instanceof WC_Product ) {
		return false;
	}
	foreach ( $source->get_children() as $child_id ) {
		$var = wc_get_product( $child_id );
		if ( $var instanceof WC_Product && $var->managing_stock() && null !== $var->get_stock_quantity() ) {
			return true;
		}
	}
	return false;
}

/** How many choice photographs the converted sets carry, for the check card's line. */
function addon_boss_variation_check_photo_count( int $draft_id ): int {
	$map  = get_post_meta( $draft_id, '_addon_boss_combo_prices', true );
	$sets = function_exists( 'addon_boss_option_sets' ) ? addon_boss_option_sets() : array();
	$n    = 0;
	foreach ( (array) ( is_array( $map ) ? ( $map['sets'] ?? array() ) : array() ) as $sid ) {
		foreach ( (array) ( $sets[ $sid ]['options'] ?? array() ) as $opt ) {
			if ( ! empty( $opt['image_id'] ) ) {
				$n++;
			}
		}
	}
	return $n;
}

/**
 * The one confirm step both converter buttons wear, printed once per screen.
 *
 * Neither button destroys anything, so this is not a warning; it is a pause.
 * The duplicate leaves a stray draft AND a stray copy of every set behind, and
 * the swap moves a live web address, and both sit inside a panel people scroll
 * through, which is exactly where a mis-click happens. The question states what
 * is about to happen in the merchant's own nouns and names the product, so a
 * person with several drafts open cannot confirm the wrong one.
 *
 * Focus lands on Cancel: for a guard whose whole job is stopping an accidental
 * activation, the safe answer is the one a stray keypress should reach first.
 *
 * With JavaScript off the links simply work, as they always did. The step is a
 * courtesy, never the authorisation: that is the nonce on the URL.
 */
function addon_boss_variation_confirm_js(): void {
	static $printed = false;
	if ( $printed ) {
		return;
	}
	$printed = true;

	$words = wp_json_encode( array(
		'cancel' => __( 'Cancel', 'addon-boss' ),
		'aria'   => __( 'Please confirm', 'addon-boss' ),
	) );

	wp_print_inline_script_tag(
		'(function(){var W=' . $words . ';' .
		'document.addEventListener("click",function(e){' .
		'var a=e.target&&e.target.closest?e.target.closest("[data-bb-ask]"):null;if(!a){return;}' .
		'if(a.dataset.bbGone){e.preventDefault();return;}' .
		'e.preventDefault();e.stopImmediatePropagation();' .
		'var row=a.closest(".bb-vc-acts,.bb-vc-handacts");if(!row||row.dataset.bbAsking){return;}' .
		'row.dataset.bbAsking="1";' .
		'var box=document.createElement("div");box.className="bb-vc-ask"+("heavy"===a.dataset.bbWeight?" is-heavy":"");' .
		'box.setAttribute("role","group");box.setAttribute("aria-label",W.aria);' .
		'var q=document.createElement("p");q.className="bb-vc-askq";q.textContent=a.dataset.bbAsk;box.appendChild(q);' .
		'var acts=document.createElement("div");acts.className="bb-vc-askacts";' .
		'var yes=document.createElement("button");yes.type="button";yes.className="button bb-cta bb-vc-askyes";yes.textContent=a.dataset.bbYes;' .
		'var no=document.createElement("button");no.type="button";no.className="button bb-vc-quiet bb-vc-askno";no.textContent=W.cancel;' .
		'acts.appendChild(yes);acts.appendChild(no);box.appendChild(acts);' .
		'row.style.display="none";row.parentNode.insertBefore(box,row.nextSibling);' .
		'function close(){box.remove();row.style.display="";delete row.dataset.bbAsking;' .
		'document.removeEventListener("keydown",esc);try{a.focus();}catch(x){}}' .
		'function esc(ev){if("Escape"===ev.key){close();}}' .
		'document.addEventListener("keydown",esc);' .
		'no.addEventListener("click",close);' .
		'yes.addEventListener("click",function(){' .
		'a.dataset.bbGone="1";' .
		'if(a.dataset.bbBusy){yes.textContent=a.dataset.bbBusy;}' .
		'yes.classList.add("disabled");no.classList.add("disabled");no.disabled=true;yes.disabled=true;' .
		'window.location.href=a.href;});' .
		'try{no.focus();}catch(x){}' .
		'},true);}());'
	);
}

/** The check card, at the top of the Product options tab on a converted draft. */
add_action( 'addon_boss_options_panel_before', 'addon_boss_variation_check_card' );
function addon_boss_variation_check_card( $product ): void {
	if ( ! $product instanceof WC_Product ) {
		return;
	}
	$id = (int) $product->get_id();
	if ( 'draft' !== get_post_status( $id ) || get_post_meta( $id, ADDON_BOSS_CHECK_DISMISSED, true ) ) {
		return;
	}
	$source_id = (int) get_post_meta( $id, ADDON_BOSS_CONVERTED_FROM, true );
	$src       = $source_id > 0 ? get_post( $source_id ) : null;
	if ( ! $src instanceof WP_Post || ! addon_boss_variation_convert_allowed( $id ) ) {
		return;
	}
	$name = $src->post_title;

	echo '<div class="bb-vc-check">';
	printf(
		'<p class="bb-vc-vlead"><strong>%1$s</strong> %2$s</p>',
		esc_html( sprintf(
			/* translators: %s: the variable product this draft was built from */
			__( 'Built from %s.', 'addon-boss' ),
			$name
		) ),
		esc_html__( 'This is a draft: nothing reaches a shopper until you publish it. Check a pair or two before you do:', 'addon-boss' )
	);

	$rows = addon_boss_variation_check_rows( $id );
	if ( $rows ) {
		echo '<table class="bb-vc-pairs"><thead><tr><th>' . esc_html__( 'Pick', 'addon-boss' ) . '</th><th>' . esc_html__( 'Charged before', 'addon-boss' ) . '</th></tr></thead><tbody>';
		foreach ( $rows as $row ) {
			// aob-money-raw: an admin check against the merchant's own stored figure.
			// "Charged before" is the variation's price as entered, the number they
			// compare the draft's page against, not a charge on a display basis.
			echo '<tr><td>' . esc_html( $row['label'] ) . '</td><td class="bb-vc-n">' . wp_kses_post( wc_price( $row['price'] ) ) . '</td></tr>';
		}
		echo '</tbody></table>';
	}

	echo '<ul class="bb-vc-vlist">';
	// Each line asks the merchant to look for what this build will show. Every
	// build shows a choice's photograph on the choice; only a build with option
	// photographs also swaps the main picture, so only that build asks for it.
	$photos = addon_boss_variation_check_photo_count( $id );
	if ( $photos > 0 && addon_boss_engine_can( 'option-photos' ) ) {
		echo '<li>' . esc_html( sprintf(
			/* translators: %s: number of choice photographs the converted sets carry */
			_n(
				'%s photograph came across. On the page, the picture should follow the choice.',
				'%s photographs came across. On the page, the picture should follow the choice.',
				$photos,
				'addon-boss'
			),
			number_format_i18n( $photos )
		) ) . '</li>';
	} elseif ( $photos > 0 ) {
		echo '<li>' . esc_html( sprintf(
			/* translators: %s: number of choice photographs the converted sets carry */
			_n(
				'%s photograph came across. On the page, it shows on its choice.',
				'%s photographs came across. On the page, each shows on its choice.',
				$photos,
				'addon-boss'
			),
			number_format_i18n( $photos )
		) ) . '</li>';
	}
	// Stock is claimed only when a pair holds a figure, which needs a build
	// that counts per pair AND a source that counted at all. A source that held
	// figures this build cannot keep gets the line saying where stock counts
	// now; a source that counted nothing gets no line, as the receipt says
	// nothing about it either.
	$pairs = addon_boss_engine_can( 'option-stock' ) && function_exists( 'addon_boss_combo_stock_all' )
		? addon_boss_combo_stock_all( $id )
		: array();
	if ( $pairs ) {
		echo '<li>' . esc_html__( 'Stock came across, one figure for each pair.', 'addon-boss' ) . '</li>';
	} elseif ( addon_boss_variation_source_held_stock( $id ) ) {
		echo '<li class="bb-vc-hollow">' . esc_html__( 'Stock counts on the product here. Set one figure under Inventory if you manage stock.', 'addon-boss' ) . '</li>';
	}
	echo '</ul>';

	echo '<div class="bb-vc-hand">' . esc_html( sprintf(
		/* translators: %s: the variable product this draft was built from */
		__( "When it reads right, this draft can take the original's place: the name and the web address change hands, the reviews come across, and %s retires to a draft. Nothing is deleted.", 'addon-boss' ),
		$name
	) ) . '</div>';

	$swap_url    = wp_nonce_url( admin_url( 'admin-post.php?action=addon_boss_variation_swap&product=' . $id ), 'addon_boss_variation_swap_' . $id );
	$dismiss_url = wp_nonce_url( admin_url( 'admin-post.php?action=addon_boss_variation_check_dismiss&product=' . $id ), 'addon_boss_variation_dismiss_' . $id );
	echo '<div class="bb-vc-handacts">';
	// The heavier ask of the two: this one publishes, moves a live web address
	// and retires the original. The question names the product so a merchant
	// with several drafts open cannot confirm the wrong one.
	printf(
		'<a class="button bb-cta" href="%1$s" data-bb-ask="%2$s" data-bb-yes="%3$s" data-bb-weight="heavy">%4$s</a>',
		esc_url( $swap_url ),
		esc_attr( sprintf(
			/* translators: %s: the original variable product's name */
			__( 'Publish this copy and give it the name and web address of %s? The original retires to a draft. Nothing is deleted.', 'addon-boss' ),
			$name
		) ),
		esc_attr__( 'Yes, swap them', 'addon-boss' ),
		esc_html__( 'Publish and take its place', 'addon-boss' )
	);
	echo '<a class="button bb-vc-quiet" href="' . esc_url( (string) get_edit_post_link( $source_id, 'url' ) ) . '">' . esc_html( sprintf(
		/* translators: %s: the original variable product's name */
		__( 'Open %s', 'addon-boss' ),
		$name
	) ) . '</a>';
	echo '<a class="bb-vc-dismiss" href="' . esc_url( $dismiss_url ) . '">' . esc_html__( 'Dismiss', 'addon-boss' ) . '</a>';
	echo '</div>';
	echo '</div>';

	// The swap is asked for before it runs, and the ask also swallows a second
	// click: two racing swap requests would re-suffix the retired original's
	// address for nothing.
	addon_boss_variation_confirm_js();

	// The build's redirect lands here, and this card IS the landing message
	// (the old success notice is gone). A card inside a closed tab is a notice
	// nobody received, so on that arrival the tab opens itself.
	wp_print_inline_script_tag(
		'jQuery(function(){if(!/[?&]addon_boss_convert=built/.test(window.location.search)){return;}' .
		'var t=document.querySelector(\'.product_data_tabs a[href="#bundle_boss_options_panel"]\');if(t){t.click();}' .
		'var c=document.querySelector(".bb-vc-check");if(c){c.scrollIntoView({block:"center"});}});'
	);
}

/**
 * Swap places: the draft goes live under the original's name and address,
 * the reviews come across, and the original retires to a draft. One move
 * doing the four finishing steps a merchant would otherwise do by hand,
 * each forgettable. Nothing is deleted.
 *
 * Requires the capability to edit BOTH products: this is the one place a
 * product's screen changes another product, so it is explicit, named on the
 * button, and double-checked here.
 */
function addon_boss_variation_swap( int $draft_id ): bool {
	$source_id = (int) get_post_meta( $draft_id, ADDON_BOSS_CONVERTED_FROM, true );
	$src       = $source_id > 0 ? get_post( $source_id ) : null;
	$dft       = get_post( $draft_id );
	if ( ! $src instanceof WP_Post || ! $dft instanceof WP_Post ) {
		return false;
	}
	if ( ! current_user_can( 'edit_post', $draft_id ) || ! current_user_can( 'edit_post', $source_id ) ) {
		return false;
	}

	$old_slug  = $src->post_name;
	$old_title = $src->post_title;

	// The original steps aside first, freeing the address for the copy to take
	// exactly: a draft still holds its slug, so without the rename the copy
	// would publish at team-tee-2 and the old address would go nowhere.
	wp_update_post(
		array(
			'ID'          => $source_id,
			'post_status' => 'draft',
			'post_name'   => $old_slug . '-variations',
		)
	);

	// The reviews are the shop's history and belong to the product shoppers
	// will meet, not to a retired draft they cannot reach.
	$comment_ids = get_comments(
		array(
			'post_id' => $source_id,
			'fields'  => 'ids',
			'status'  => 'any',
		)
	);
	foreach ( $comment_ids as $cid ) {
		wp_update_comment(
			array(
				'comment_ID'      => (int) $cid,
				'comment_post_ID' => $draft_id,
			)
		);
	}
	wp_update_comment_count( $source_id );
	wp_update_comment_count( $draft_id );
	if ( class_exists( 'WC_Comments' ) && method_exists( 'WC_Comments', 'clear_transients' ) ) {
		WC_Comments::clear_transients( $source_id );
		WC_Comments::clear_transients( $draft_id );
	}

	wp_update_post(
		array(
			'ID'          => $draft_id,
			'post_status' => 'publish',
			'post_title'  => $old_title,
			'post_name'   => $old_slug,
		)
	);
	if ( function_exists( 'wc_delete_product_transients' ) ) {
		wc_delete_product_transients( $source_id );
		wc_delete_product_transients( $draft_id );
	}
	return true;
}

function addon_boss_variation_swap_handle(): void {
	$draft = isset( $_GET['product'] ) ? (int) $_GET['product'] : 0;
	check_admin_referer( 'addon_boss_variation_swap_' . $draft );
	if ( $draft < 1 || ! addon_boss_variation_swap( $draft ) ) {
		wp_die( esc_html__( 'Sorry, you are not allowed to swap these products.', 'addon-boss' ), '', array( 'response' => 403 ) );
	}
	wp_safe_redirect( add_query_arg( 'addon_boss_convert', 'swapped', get_edit_post_link( $draft, 'url' ) ) );
	exit;
}
add_action( 'admin_post_addon_boss_variation_swap', 'addon_boss_variation_swap_handle' );

function addon_boss_variation_check_dismiss_handle(): void {
	$draft = isset( $_GET['product'] ) ? (int) $_GET['product'] : 0;
	check_admin_referer( 'addon_boss_variation_dismiss_' . $draft );
	if ( $draft < 1 || ! current_user_can( 'edit_post', $draft ) ) {
		wp_die( esc_html__( 'Sorry, you are not allowed to edit this product.', 'addon-boss' ), '', array( 'response' => 403 ) );
	}
	update_post_meta( $draft, ADDON_BOSS_CHECK_DISMISSED, '1' );
	wp_safe_redirect( (string) get_edit_post_link( $draft, 'url' ) );
	exit;
}
add_action( 'admin_post_addon_boss_variation_check_dismiss', 'addon_boss_variation_check_dismiss_handle' );

/** Build it, then put the merchant in front of the draft rather than a message about it. */
function addon_boss_variation_convert_handle(): void {
	$id = isset( $_GET['product'] ) ? (int) $_GET['product'] : 0;
	if ( $id < 1 || ! addon_boss_variation_convert_allowed( $id ) ) {
		wp_die( esc_html__( 'Sorry, you are not allowed to duplicate this product.', 'addon-boss' ), '', array( 'response' => 403 ) );
	}
	check_admin_referer( 'addon_boss_variation_convert_' . $id );

	$draft = addon_boss_variation_build( addon_boss_variation_plan( $id ) );
	if ( $draft < 1 ) {
		wp_safe_redirect( add_query_arg( 'addon_boss_convert', 'failed', get_edit_post_link( $id, 'url' ) ) );
		exit;
	}
	wp_safe_redirect( add_query_arg( 'addon_boss_convert', 'built', get_edit_post_link( $draft, 'url' ) ) );
	exit;
}
add_action( 'admin_post_addon_boss_variation_convert', 'addon_boss_variation_convert_handle' );

/** What happened, said on the screen the merchant lands on. */
add_action(
	'admin_notices',
	static function () {
		$state = isset( $_GET['addon_boss_convert'] ) ? sanitize_key( wp_unslash( $_GET['addon_boss_convert'] ) ) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- reading our own redirect flag to print a notice.
		// 'built' prints nothing: the check card at the top of the Product
		// options tab IS the landing message, and saying it twice on one
		// screen is how the box card came to repeat its fill instruction.
		if ( 'swapped' === $state ) {
			echo '<div class="notice notice-success"><p>' . esc_html__( 'Live. This product now holds the name, the web address and the reviews. The variable original is retired to a draft.', 'addon-boss' ) . '</p></div>';
			return;
		}
		if ( 'failed' === $state ) {
			echo '<div class="notice notice-error"><p>' . esc_html__( 'Nothing was changed. This product has no attributes its variations vary on.', 'addon-boss' ) . '</p></div>';
		}
	}
);