<?php
namespace StoreSuit;
defined( 'ABSPATH' ) || exit;

/**
 * Pick list (0.60): the products of the orders selected on the order desk in one printable list, so one walk through the
 * shelves picks them all. Each product (each variation apart) appears once with the units still to pick (ordered, less
 * refunded and already picked units) and the orders they go to; the list follows SKU, then name. Closed orders (cancelled,
 * failed, refunded, drafts) are left out and named. Nothing is written; read with the orders permission, like the address
 * labels.
 */
final class PickList {
    public const ACTION = 'storesuit_pick_list';

    /** The printed list's style (A4; the toolbar is not printed). */
    private const CSS = '@page{size:A4;margin:12mm}
*{box-sizing:border-box}
body{margin:0;color:#121212;font:13px/1.4 Arial,sans-serif;background:#fff}
.toolbar{display:flex;gap:10px;justify-content:center;padding:10px;background:#f1f1f1}
.toolbar button{font:inherit;padding:8px 14px}
main{max-width:190mm;margin:0 auto;padding:10px}
h1{font-size:20px;margin:0 0 4px}
.meta{margin:0 0 12px;color:#444}
table{width:100%;border-collapse:collapse}
th,td{border-bottom:1px solid #bbb;padding:6px 5px;text-align:left;vertical-align:top}
th{font-size:11px;text-transform:uppercase;color:#333}
td small{display:block;color:#444}
.qty{font-size:18px;font-weight:bold;width:52px;text-align:right}
.tick{width:26px}
.tick span{display:inline-block;width:16px;height:16px;border:2px solid #121212}
.code{font-family:monospace;white-space:nowrap}
.for{font-size:12px}
h2{font-size:15px;margin:18px 0 6px}
ul{margin:0;padding-left:18px}
.screen-reader-text{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
@media print{.toolbar{display:none}main{padding:0}tr{break-inside:avoid}}';

    public static function hooks(): void {
        add_action( 'admin_post_' . self::ACTION, array( __CLASS__, 'print_page' ) );
    }

    public static function print_page(): void {
        if ( ! current_user_can( 'storesuit_orders' ) ) { wp_die( esc_html( I18n::t( 'You do not have permission to perform this action.' ) ), '', array( 'response'=>403 ) ); }
        check_admin_referer( self::ACTION );
        $raw = isset( $_GET['order_ids'] ) ? array_map( 'absint', (array) wp_unslash( $_GET['order_ids'] ) ) : array();
        $ids = array_values( array_unique( array_filter( $raw ) ) );
        if ( ! $ids || count( $ids ) > 100 ) { wp_die( esc_html( I18n::t( 'Select 1–100 orders.' ) ), 400 ); }
        // A selection with nothing to print (every order closed) says so instead of failing (review 0.59).
        try { $body = self::body( $ids ); } catch ( \Throwable $e ) { wp_die( esc_html( $e->getMessage() ), '', array( 'response'=>400, 'back_link'=>true ) ); }
        nocache_headers();
        header( 'Content-Type: text/html; charset=' . get_option( 'blog_charset' ) );
        PackingSlips::render( 'storesuit-pick-list', I18n::t( 'Pick list' ), self::CSS, $body );
        exit;
    }

    /**
     * The list: rows of product, SKU, what the product is (variation attributes), units to pick and the orders with their
     * units; the orders that count and those left out. Up to 100 orders.
     */
    public static function build( array $ids ): array {
        Store::require_cap( 'storesuit_orders' );
        $rows = array(); $orders = array(); $skipped = array();
        foreach ( array_slice( array_values( array_unique( array_filter( array_map( 'absint', $ids ) ) ) ), 0, 100 ) as $id ) {
            $order = wc_get_order( $id );
            if ( ! $order instanceof \WC_Order || $order->get_type() !== 'shop_order' ) { continue; }
            if ( $order->has_status( array( 'cancelled', 'failed', 'refunded', 'trash', 'checkout-draft' ) ) || SaleStatus::quote( $order ) ) { $skipped[] = (string) $order->get_order_number(); continue; }
            $progress = (array) ( $order->get_meta( '_storesuit_fulfilment' ) ?: array() ); $units = 0.0;
            foreach ( $order->get_items() as $item_id => $item ) {
                if ( ! $item instanceof \WC_Order_Item_Product ) { continue; }
                $left = (float) $item->get_quantity() - abs( (float) $order->get_qty_refunded_for_item( $item_id ) ) - max( 0.0, (float) ( $progress[ $item_id ]['picked'] ?? 0 ) );
                if ( $left <= 0 ) { continue; }
                $product = $item->get_product(); $key = $item->get_variation_id() ?: $item->get_product_id() ?: 'item-' . $item_id;
                if ( ! isset( $rows[ $key ] ) ) {
                    $rows[ $key ] = array( 'name'=>$product ? $product->get_name() : $item->get_name(), 'sku'=>$product ? (string) $product->get_sku() : '', 'gtin'=>$product && is_callable( array( $product, 'get_global_unique_id' ) ) ? (string) $product->get_global_unique_id() : '', 'what'=>self::attributes( $item ), 'qty'=>0.0, 'orders'=>array() );
                }
                $rows[ $key ]['qty'] += $left; $number = (string) $order->get_order_number();
                $rows[ $key ]['orders'][ $number ] = ( $rows[ $key ]['orders'][ $number ] ?? 0 ) + $left; $units += $left;
            }
            $orders[] = array( 'number'=>(string) $order->get_order_number(), 'name'=>trim( $order->get_formatted_billing_full_name() ), 'delivery'=>$order->get_meta( '_storesuit_delivery' ) === 'pickup' ? 'pickup' : 'shipping', 'units'=>$units );
        }
        $rows = array_values( $rows );
        usort( $rows, static fn( $a, $b ) => ( $a['sku'] === '' ) <=> ( $b['sku'] === '' ) ?: strnatcasecmp( $a['sku'], $b['sku'] ) ?: strnatcasecmp( $a['name'], $b['name'] ) );
        return array( 'rows'=>$rows, 'orders'=>$orders, 'skipped'=>$skipped, 'units'=>array_sum( array_column( $rows, 'qty' ) ) );
    }

    /**
     * When the list was printed, in the reader's language and the store's time zone ("9 Oct 2026, 14:09"), as the screens
     * write dates (KIT-3); WordPress's own date format where PHP has no intl extension.
     */
    private static function printed_at(): string {
        if ( class_exists( '\IntlDateFormatter' ) ) {
            $format = new \IntlDateFormatter( I18n::locale(), \IntlDateFormatter::MEDIUM, \IntlDateFormatter::SHORT, wp_timezone() );
            $text = $format->format( time() );
            if ( is_string( $text ) && $text !== '' ) { return $text; }
        }
        return wp_date( get_option( 'date_format' ) . ' ' . get_option( 'time_format' ) );
    }

    /** A variation's choices as the order line keeps them ("Colour: Red, Size: M"). */
    private static function attributes( \WC_Order_Item_Product $item ): string {
        $parts = array();
        foreach ( $item->get_formatted_meta_data( '_', true ) as $meta ) { $parts[] = wp_strip_all_tags( (string) $meta->display_key ) . ': ' . wp_strip_all_tags( (string) $meta->display_value ); }
        return implode( ', ', $parts );
    }

    /** The complete printed list of the selected orders (what print_page() prints). */
    public static function document( array $ids ): string {
        return PackingSlips::capture( 'storesuit-pick-list', I18n::t( 'Pick list' ), self::CSS, self::body( $ids ) );
    }

    /** The list's body: the toolbar with its Print button, the rows to pick, the orders in the list and those left out. */
    private static function body( array $ids ): string {
        $list = self::build( $ids );
        if ( ! $list['orders'] ) { throw new \InvalidArgumentException( esc_html( I18n::t( 'No orders found to print.' ) ) ); }
        $qty = static fn( $n ) => esc_html( wc_stock_amount( $n ) );
        $body = '';
        foreach ( $list['rows'] as $row ) {
            $orders = array(); foreach ( $row['orders'] as $number => $n ) { $orders[] = '#' . esc_html( $number ) . ' × ' . $qty( $n ); }
            $body .= '<tr><td class="tick"><span aria-hidden="true"></span></td><td class="qty">' . $qty( $row['qty'] ) . '</td><td><strong>' . esc_html( $row['name'] ) . '</strong>' . ( $row['what'] !== '' ? '<small>' . esc_html( $row['what'] ) . '</small>' : '' ) . '</td><td class="code">' . esc_html( $row['sku'] ) . ( $row['gtin'] !== '' ? '<small>' . esc_html( $row['gtin'] ) . '</small>' : '' ) . '</td><td class="for">' . implode( ', ', $orders ) . '</td></tr>';
        }
        $order_rows = '';
        foreach ( $list['orders'] as $o ) { $order_rows .= '<li><strong>#' . esc_html( $o['number'] ) . '</strong> ' . esc_html( $o['name'] ) . ' · ' . esc_html( $o['delivery'] === 'pickup' ? I18n::t( 'Store pickup' ) : I18n::t( 'Shipping' ) ) . ' · ' . esc_html( I18n::n( '%s unit to pick', '%s units to pick', wc_stock_amount( $o['units'] ) ) ) . '</li>'; }
        return '<div class="toolbar"><button type="button" class="ss-print">' . esc_html( I18n::t( 'Print' ) ) . '</button></div><main>'
            . '<h1>' . esc_html( I18n::t( 'Pick list' ) ) . '</h1><p class="meta">' . esc_html( implode( ' · ', array( I18n::n( '%s order', '%s orders', count( $list['orders'] ) ), I18n::n( '%s product', '%s products', count( $list['rows'] ) ), I18n::n( '%s unit', '%s units', wc_stock_amount( $list['units'] ) ), self::printed_at() ) ) ) . '</p>'
            . ( $list['rows'] ? '<table><thead><tr><th><span class="screen-reader-text">' . esc_html( I18n::t( 'Picked' ) ) . '</span></th><th>' . esc_html( I18n::t( 'Units' ) ) . '</th><th>' . esc_html( I18n::t( 'Product' ) ) . '</th><th>' . esc_html( I18n::t( 'SKU' ) ) . '</th><th>' . esc_html( I18n::t( 'For orders' ) ) . '</th></tr></thead><tbody>' . $body . '</tbody></table>' : '<p>' . esc_html( I18n::t( 'Everything in these orders is already picked.' ) ) . '</p>' )
            . '<h2>' . esc_html( I18n::t( 'Orders in this list' ) ) . '</h2><ul>' . $order_rows . '</ul>'
            . ( $list['skipped'] ? '<p class="meta">' . esc_html( I18n::format( 'Left out (closed): %s', '#' . implode( ', #', $list['skipped'] ) ) ) . '</p>' : '' )
            . '</main>';
    }
}