<?php
/**
 * Message Builder
 *
 * @package OrderCourier
 */

namespace Prologic365\OrderCourier;

defined( 'ABSPATH' ) || exit;

/**
 * Message Builder class.
 */
class Message_Builder {
	/**
	 * Maximum message length (WhatsApp URL length limit).
	 */
	const MAX_LENGTH = 4000;

	/**
	 * Build message for an order.
	 *
	 * @param \WC_Order $order Order object.
	 * @param string    $template_type Template type (order, quote, or status).
	 * @return string
	 */
	public static function for_order( $order, $template_type = 'order' ) {
		$templates = get_option( 'ordercourier_templates', array() );
		$template  = '';

		if ( 'quote' === $template_type ) {
			$template = isset( $templates['quote_template'] ) ? $templates['quote_template'] : '';
		} else {
			$template = isset( $templates['order_template'] ) ? $templates['order_template'] : '';
		}

		/**
		 * Filter the message template.
		 *
		 * @since 1.0.0
		 * @param string $template Template string.
		 * @param string $template_type Template type (order, quote, status).
		 * @param \WC_Order $order Order object.
		 */
		$template = apply_filters( 'ordercourier_message_template', $template, $template_type, array( 'order' => $order ) );

		$placeholders = self::get_order_placeholders( $order );

		// Mixed quote orders: show subtotal, shipping and total of the priced items.
		if ( 'quote' === $template_type ) {
			$placeholders['{items}'] .= self::format_quote_totals( $order );
		}

		$message = self::replace_placeholders( $template, $placeholders );
		$message = self::normalize_message( $message );
		$message = self::truncate_message( $message, $order );

		/**
		 * Filter the final message before it's sent.
		 *
		 * @since 1.0.0
		 * @param string $message Final message string.
		 * @param \WC_Order $order Order object.
		 * @param string $template_type Template type.
		 */
		return apply_filters( 'ordercourier_final_message', $message, $order, $template_type );
	}

	/**
	 * Build message for a cart.
	 *
	 * @param \WC_Cart $cart Cart object.
	 * @return string
	 */
	public static function for_cart( $cart ) {
		$templates = get_option( 'ordercourier_templates', array() );
		$template  = isset( $templates['order_template'] ) ? $templates['order_template'] : '';

		// Check if cart contains only quote-only items.
		$has_priced_items = false;
		foreach ( $cart->get_cart() as $cart_item ) {
			if ( ! Order_Manager::is_quote_product( $cart_item['data'] ) ) {
				$has_priced_items = true;
				break;
			}
		}

		// If quote-only, remove template lines containing price placeholders.
		if ( ! $has_priced_items ) {
			$template = self::remove_price_lines( $template );
		}

		$placeholders = self::get_cart_placeholders( $cart );
		$message      = self::replace_placeholders( $template, $placeholders );
		$message      = self::normalize_message( $message );

		return $message;
	}

	/**
	 * Build message for a product.
	 *
	 * @param int   $product_id Product ID.
	 * @param array $data Additional data (variation_id, quantity, etc).
	 * @return string
	 */
	public static function for_product( $product_id, $data = array() ) {
		$templates = get_option( 'ordercourier_templates', array() );
		$template  = isset( $templates['product_template'] ) ? $templates['product_template'] : '';

		$placeholders = self::get_product_placeholders( $product_id, $data );
		$message      = self::replace_placeholders( $template, $placeholders );
		$message      = self::normalize_message( $message );

		return $message;
	}

	/**
	 * Get placeholders for an order.
	 *
	 * @param \WC_Order $order Order object.
	 * @return array
	 */
	private static function get_order_placeholders( $order ) {
		$items_text   = self::format_order_items( $order );
		$coupons_text = self::format_coupons( $order );
		$fees_text    = self::format_fees( $order );

		/**
		 * Filter to modify items text before placeholder replacement.
		 *
		 * @since 1.0.0
		 * @param string    $items_text Formatted items text.
		 * @param \WC_Order $order Order object.
		 */
		$items_text = apply_filters( 'ordercourier_format_order_items', $items_text, $order );

		// Only format addresses if they have data.
		$shipping_addr = $order->get_address( 'shipping' );
		$billing_addr  = $order->get_address( 'billing' );

		$address_text = self::format_address( $shipping_addr );
		$billing_text = self::format_address( $billing_addr );

		// Get customer name, phone, email - only show if available.
		$customer_name  = $order->get_formatted_billing_full_name();
		$customer_phone = $order->get_billing_phone();
		$customer_email = $order->get_billing_email();

		// Get order link (order-received for guests, view-order for logged in).
		$order_link = $order->get_checkout_order_received_url();

		// Calculate total excluding quote items.
		$order_total = $order->get_total();
		$quote_total = 0.0;
		foreach ( $order->get_items() as $item ) {
			$product = $item->get_product();
			if ( $product && Order_Manager::is_quote_product( $product ) ) {
				$quote_total += (float) $item->get_total() + (float) $item->get_total_tax();
			}
		}

		$placeholders = array(
			'{order_number}'     => $order->get_order_number(),
			'{items}'            => $items_text,
			'{item_meta}'        => '',
			'{coupons}'          => $coupons_text,
			'{discount}'         => html_entity_decode( wp_strip_all_tags( wc_price( $order->get_discount_total() ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' ),
			'{fees}'             => $fees_text,
			'{shipping_method}'  => $order->get_shipping_method(),
			'{shipping_total}'   => html_entity_decode( wp_strip_all_tags( wc_price( $order->get_shipping_total() + $order->get_shipping_tax() ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' ),
			'{tax}'              => html_entity_decode( wp_strip_all_tags( wc_price( self::get_order_tax_excluding_quote_items( $order ) ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' ),
			'{total}'            => html_entity_decode( wp_strip_all_tags( wc_price( $order_total - $quote_total ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' ),
			'{customer_name}'    => $customer_name,
			'{phone}'            => $customer_phone,
			'{email}'            => $customer_email,
			'{billing_address}'  => $billing_text,
			'{shipping_address}' => $address_text,
			'{note}'             => $order->get_customer_note() ? __( 'Note:', 'ordercourier' ) . ' ' . $order->get_customer_note() : '',
			'{checkout_fields}'  => self::format_checkout_fields( $order ),
			'{pay_link}'         => $order->get_checkout_payment_url(),
			'{order_link}'       => $order_link,
			'{site_name}'        => get_bloginfo( 'name' ),
			'{date}'             => $order->get_date_created()->date_i18n( wc_date_format() ),
		);

		/**
		 * Filter message placeholders for orders.
		 *
		 * @since 1.0.0
		 * @param array     $placeholders Key => value pairs of placeholders.
		 * @param \WC_Order $order Order object.
		 */
		return apply_filters( 'ordercourier_message_placeholders', $placeholders, 'order', $order );
	}

	/**
	 * Get order tax excluding quote-only items.
	 *
	 * @param \WC_Order $order Order object.
	 * @return float Tax amount excluding quote items.
	 */
	private static function get_order_tax_excluding_quote_items( $order ) {
		$total_tax = $order->get_total_tax();
		$quote_tax = 0.0;

		foreach ( $order->get_items() as $item ) {
			$product = $item->get_product();
			if ( $product && Order_Manager::is_quote_product( $product ) ) {
				$quote_tax += (float) $item->get_total_tax();
			}
		}

		return $total_tax - $quote_tax;
	}

	/**
	 * Get placeholders for a cart.
	 *
	 * @param \WC_Cart $cart Cart object.
	 * @return array
	 */
	private static function get_cart_placeholders( $cart ) {
		$items_text = self::format_cart_items( $cart );

		// Check if cart contains only quote-only items.
		$has_priced_items = false;
		$has_quote_items  = false;
		foreach ( $cart->get_cart() as $cart_item ) {
			if ( Order_Manager::is_quote_product( $cart_item['data'] ) ) {
				$has_quote_items = true;
			} else {
				$has_priced_items = true;
			}
		}

		// If cart has ONLY quote items, omit price totals.
		if ( $has_quote_items && ! $has_priced_items ) {
			$shipping_method = '';
			$shipping_total  = '';
			$tax             = '';
			$total           = '';
		} else {
			// Calculate shipping before getting method name.
			if ( ! WC()->cart->is_empty() && WC()->cart->needs_shipping() ) {
				WC()->cart->calculate_shipping();
			}

			// Get shipping method name from chosen rate.
			$shipping_method = '';
			$chosen_methods  = WC()->session ? WC()->session->get( 'chosen_shipping_methods' ) : array();
			if ( ! empty( $chosen_methods ) ) {
				$packages = WC()->shipping()->get_packages();
				if ( ! empty( $packages ) && ! empty( $packages[0]['rates'] ) ) {
					foreach ( $packages[0]['rates'] as $rate ) {
						if ( $rate->id === $chosen_methods[0] ) {
							$shipping_method = $rate->get_label();
							break;
						}
					}
				}
			}

			// For mixed carts, subtract quote items' tax from total tax.
			$quote_tax = 0.0;
			if ( $has_quote_items ) {
				foreach ( $cart->get_cart() as $cart_item ) {
					if ( Order_Manager::is_quote_product( $cart_item['data'] ) ) {
						$quote_tax += (float) $cart_item['line_tax'];
					}
				}
			}

			// For mixed carts, subtract quote items from total.
			$quote_total = 0.0;
			if ( $has_quote_items ) {
				foreach ( $cart->get_cart() as $cart_item ) {
					if ( Order_Manager::is_quote_product( $cart_item['data'] ) ) {
						$quote_total += (float) $cart_item['line_total'] + (float) $cart_item['line_tax'];
					}
				}
			}

			$shipping_total = html_entity_decode( wp_strip_all_tags( wc_price( $cart->get_shipping_total() + $cart->get_shipping_tax() ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$tax            = html_entity_decode( wp_strip_all_tags( wc_price( $cart->get_total_tax() - $quote_tax ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$total          = html_entity_decode( wp_strip_all_tags( wc_price( $cart->get_total( 'raw' ) - $quote_total ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
		}

		return array(
			'{order_number}'     => '', // No order number for cart (direct mode).
			'{items}'            => $items_text,
			'{item_meta}'        => '',
			'{coupons}'          => self::format_cart_coupons( $cart ),
			'{discount}'         => html_entity_decode( wp_strip_all_tags( wc_price( $cart->get_discount_total() ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' ),
			'{fees}'             => self::format_cart_fees( $cart ),
			'{shipping_method}'  => $shipping_method,
			'{shipping_total}'   => $shipping_total,
			'{tax}'              => $tax,
			'{total}'            => $total,
			'{customer_name}'    => '',
			'{phone}'            => '',
			'{email}'            => '',
			'{billing_address}'  => '',
			'{shipping_address}' => '',
			'{note}'             => '',
			'{checkout_fields}'  => '',
			'{pay_link}'         => '',
			'{order_link}'       => '', // No order link for cart (direct mode).
			'{site_name}'        => get_bloginfo( 'name' ),
			'{date}'             => current_time( wc_date_format() ),
		);
	}

	/**
	 * Get placeholders for a product.
	 *
	 * @param int   $product_id Product ID.
	 * @param array $data Additional data.
	 * @return array
	 */
	private static function get_product_placeholders( $product_id, $data ) {
		$product      = wc_get_product( $product_id );
		$variation_id = isset( $data['variation_id'] ) ? absint( $data['variation_id'] ) : 0;
		$quantity     = isset( $data['quantity'] ) ? absint( $data['quantity'] ) : 1;

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

		$item_text = $quantity . ' x ' . $product->get_name();

		if ( $product->is_type( 'variation' ) ) {
			$attributes = $product->get_variation_attributes();
			if ( ! empty( $attributes ) ) {
				$attr_text = array();
				foreach ( $attributes as $attr_name => $attr_value ) {
					$attr_text[] = wc_attribute_label( str_replace( 'attribute_', '', $attr_name ) ) . ': ' . $attr_value;
				}
				$item_text .= ' (' . implode( ', ', $attr_text ) . ')';
			}
		}

		$price = $product->get_price();
		if ( Order_Manager::is_quote_product( $product ) ) {
			$item_text .= ' - ' . __( 'Price on request', 'ordercourier' );
		} elseif ( '' !== $price ) {
			$price_html = wc_price( $price * $quantity );
			$price_text = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$item_text .= ' - ' . $price_text;
		}

		return array(
			'{items}'           => $item_text,
			'{site_name}'       => get_bloginfo( 'name' ),
			'{customer_name}'   => '',
			'{phone}'           => '',
			'{email}'           => '',
			'{order_number}'    => '',
			'{shipping_method}' => '',
			'{shipping_total}'  => '',
			'{tax}'             => '',
			'{total}'           => '',
			'{order_link}'      => '',
			'{pay_link}'        => '',
			'{date}'            => current_time( wc_date_format() ),
		);
	}

	/**
	 * Format order items.
	 *
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function format_order_items( $order ) {
		$items    = array();
		$is_quote = Order_Manager::is_quote_order( $order );

		foreach ( $order->get_items() as $item ) {
			$product   = $item->get_product();
			$item_name = $item->get_name();
			$item_text = $item->get_quantity() . ' x ' . $item_name;

			// Add variation attributes only if not already in item name.
			if ( $product && $product->is_type( 'variation' ) ) {
				$formatted_variation = wc_get_formatted_variation( $product, true, false );
				if ( $formatted_variation ) {
					$variation_plain = wp_strip_all_tags( $formatted_variation );
					// Only add if the item name doesn't already contain the variation details.
					if ( false === stripos( $item_name, $variation_plain ) ) {
						$item_text .= "\n  " . $variation_plain;
					}
				}
			}

			// Add item meta (product add-ons, etc).
			$meta_data = $item->get_formatted_meta_data( '' );
			if ( ! empty( $meta_data ) ) {
				foreach ( $meta_data as $meta ) {
					// Skip variation attributes already shown.
					if ( $product && $product->is_type( 'variation' ) && 0 === strpos( $meta->key, 'pa_' ) ) {
						continue;
					}
					$item_text .= "\n  " . wp_strip_all_tags( $meta->display_key ) . ': ' . wp_strip_all_tags( $meta->display_value );
				}
			}

			// Add price or "Price on request".
			$item_total    = $item->get_total();
			$is_quote_item = false;
			$is_no_price   = 0.0 === (float) $item_total;

			// Check if item is quote-only (check parent for variations).
			if ( $product ) {
				$product_id    = $product->is_type( 'variation' ) ? $product->get_parent_id() : $product->get_id();
				$quote_only    = get_post_meta( $product_id, '_oc_quote_only', true );
				$is_quote_item = 'yes' === $quote_only || '' === $product->get_price();
			}

			if ( $is_quote_item || ( $is_quote && $is_no_price ) ) {
				$item_text .= ' - ' . __( 'Price on request', 'ordercourier' );
			} else {
				$price_html = wc_price( $item_total );
				$price_text = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
				$item_text .= ' - ' . $price_text;
			}

			$items[] = $item_text;
		}

		return implode( "\n", $items );
	}

	/**
	 * Format cart items.
	 *
	 * @param \WC_Cart $cart Cart object.
	 * @return string
	 */
	private static function format_cart_items( $cart ) {
		$items = array();

		foreach ( $cart->get_cart() as $cart_item ) {
			$product   = $cart_item['data'];
			$item_name = $product->get_name();
			$item_text = $cart_item['quantity'] . ' x ' . $item_name;

			// Add variation attributes only if not already in item name.
			if ( $product->is_type( 'variation' ) ) {
				$formatted_variation = wc_get_formatted_variation( $product, true, false );
				if ( $formatted_variation ) {
					$variation_plain = wp_strip_all_tags( $formatted_variation );
					// Only add if the item name doesn't already contain the variation details.
					if ( false === stripos( $item_name, $variation_plain ) ) {
						$item_text .= "\n  " . $variation_plain;
					}
				}
			}

			// Add cart item data (product add-ons, etc).
			if ( ! empty( $cart_item['addons'] ) ) {
				foreach ( $cart_item['addons'] as $addon ) {
					$item_text .= "\n  " . $addon['name'] . ': ' . $addon['value'];
				}
			}

			// Add price or "Price on request" for quote-only items.
			$product_id  = $product->is_type( 'variation' ) ? $product->get_parent_id() : $product->get_id();
			$quote_only  = get_post_meta( $product_id, '_oc_quote_only', true );
			$is_no_price = '' === $product->get_price();

			if ( 'yes' === $quote_only || $is_no_price ) {
				$item_text .= ' - ' . __( 'Price on request', 'ordercourier' );
			} else {
				$price_html = wc_price( $cart_item['line_total'] );
				$price_text = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
				$item_text .= ' - ' . $price_text;
			}

			$items[] = $item_text;
		}

		return implode( "\n", $items );
	}

	/**
	 * Format subtotal, shipping and total for the priced items of a quote order.
	 * Returns '' when every item is quote-only.
	 *
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function format_quote_totals( $order ) {
		$subtotal    = 0.0;
		$quote_total = 0.0;
		$quote_tax   = 0.0;
		$has_priced  = false;

		foreach ( $order->get_items() as $item ) {
			if ( Order_Manager::is_quote_product( $item->get_product() ) ) {
				$quote_total += (float) $item->get_total() + (float) $item->get_total_tax();
				$quote_tax   += (float) $item->get_total_tax();
				continue;
			}
			$has_priced = true;
			$subtotal  += (float) $item->get_total();
		}

		if ( ! $has_priced ) {
			return '';
		}

		$plain = function ( $amount ) {
			return html_entity_decode( wp_strip_all_tags( wc_price( $amount ) ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
		};

		$text = "\n\n*" . __( 'Subtotal:', 'ordercourier' ) . '* ' . $plain( $subtotal );

		if ( $order->get_items( 'shipping' ) ) {
			$method = $order->get_shipping_method();
			$text  .= "\n*" . __( 'Shipping:', 'ordercourier' ) . '* ' . ( $method ? $method . ' - ' : '' ) . $plain( (float) $order->get_shipping_total() + (float) $order->get_shipping_tax() );
		}

		$tax = (float) $order->get_total_tax() - $quote_tax;
		if ( $tax > 0 ) {
			$text .= "\n*" . __( 'Tax:', 'ordercourier' ) . '* ' . $plain( $tax );
		}

		$text .= "\n*" . __( 'Total:', 'ordercourier' ) . '* ' . $plain( (float) $order->get_total() - $quote_total );

		return $text;
	}

	/**
	 * Format coupons.
	 *
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function format_coupons( $order ) {
		$coupons = $order->get_items( 'coupon' );
		if ( empty( $coupons ) ) {
			return '';
		}

		$coupon_texts = array();
		foreach ( $coupons as $coupon_item ) {
			$coupon_code    = $coupon_item->get_code();
			$discount       = $coupon_item->get_discount();
			$price_html     = wc_price( $discount );
			$price_text     = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$coupon_texts[] = sprintf(
				'%s (-%s)',
				$coupon_code,
				$price_text
			);
		}

		$text = '*' . __( 'Coupons:', 'ordercourier' ) . '* ' . implode( ', ', $coupon_texts ) . "\n";
		return $text;
	}

	/**
	 * Format cart coupons.
	 *
	 * @param \WC_Cart $cart Cart object.
	 * @return string
	 */
	private static function format_cart_coupons( $cart ) {
		$coupons = $cart->get_applied_coupons();
		if ( empty( $coupons ) ) {
			return '';
		}

		$text = '*' . __( 'Coupons:', 'ordercourier' ) . '* ' . implode( ', ', $coupons ) . "\n";
		return $text;
	}

	/**
	 * Format fees.
	 *
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function format_fees( $order ) {
		$fees = $order->get_fees();
		if ( empty( $fees ) ) {
			return '';
		}

		$text = '';
		foreach ( $fees as $fee ) {
			$price_html = wc_price( $fee->get_total() );
			$price_text = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$text      .= '*' . $fee->get_name() . ':* ' . $price_text . "\n";
		}
		return $text;
	}

	/**
	 * Format cart fees.
	 *
	 * @param \WC_Cart $cart Cart object.
	 * @return string
	 */
	private static function format_cart_fees( $cart ) {
		$fees = $cart->get_fees();
		if ( empty( $fees ) ) {
			return '';
		}

		$text = '';
		foreach ( $fees as $fee ) {
			$price_html = wc_price( $fee->total );
			$price_text = html_entity_decode( wp_strip_all_tags( $price_html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
			$text      .= '*' . $fee->name . ':* ' . $price_text . "\n";
		}
		return $text;
	}

	/**
	 * Format address.
	 *
	 * @param array $address Address data.
	 * @return string
	 */
	private static function format_address( $address ) {
		$parts = array_filter(
			array(
				isset( $address['address_1'] ) ? $address['address_1'] : '',
				isset( $address['address_2'] ) ? $address['address_2'] : '',
				isset( $address['city'] ) ? $address['city'] : '',
				isset( $address['state'] ) ? $address['state'] : '',
				isset( $address['postcode'] ) ? $address['postcode'] : '',
				isset( $address['country'] ) ? WC()->countries->countries[ $address['country'] ] ?? $address['country'] : '',
			)
		);
		return implode( ', ', $parts );
	}

	/**
	 * Remove template lines containing price placeholders for quote-only carts.
	 *
	 * @param string $template Template string.
	 * @return string
	 */
	private static function remove_price_lines( $template ) {
		$price_placeholders = array( '{shipping_method}', '{shipping_total}', '{tax}', '{total}' );
		$lines              = explode( "\n", $template );
		$filtered_lines     = array();

		foreach ( $lines as $line ) {
			$has_price_placeholder = false;
			foreach ( $price_placeholders as $placeholder ) {
				if ( false !== strpos( $line, $placeholder ) ) {
					$has_price_placeholder = true;
					break;
				}
			}

			if ( ! $has_price_placeholder ) {
				$filtered_lines[] = $line;
			}
		}

		return implode( "\n", $filtered_lines );
	}

	/**
	 * Replace placeholders in template.
	 *
	 * @param string $template Template string.
	 * @param array  $placeholders Placeholders array.
	 * @return string
	 */
	private static function replace_placeholders( $template, $placeholders ) {
		// First, remove lines where placeholder is empty (like "View order: {order_link}" when order_link is empty).
		foreach ( $placeholders as $key => $value ) {
			if ( '' === $value ) {
				// Remove lines that contain ONLY this placeholder with optional label prefix.
				// Pattern: "Label: {placeholder}" or "Label {placeholder}" or just "{placeholder}".
				$pattern  = '/^[^{\n]*' . preg_quote( $key, '/' ) . '\s*$/m';
				$template = preg_replace( $pattern, '', $template );
			}
		}

		return str_replace( array_keys( $placeholders ), array_values( $placeholders ), $template );
	}

	/**
	 * Normalize message.
	 *
	 * @param string $message Message.
	 * @return string
	 */
	private static function normalize_message( $message ) {
		// Strip HTML tags.
		$message = wp_strip_all_tags( $message );

		// Normalize line breaks.
		$message = str_replace( array( "\r\n", "\r" ), "\n", $message );

		// Convert whitespace-only lines to empty lines.
		$message = preg_replace( '/^[ \t]+$/m', '', $message );

		// Remove "*New Order #*" when there's no order number (direct mode).
		$message = str_replace( '*New Order #*', '', $message );

		// Fix shipping line with empty method name: "*Shipping:*  - Rs" → "*Shipping:* Rs".
		$message = preg_replace( '/\*Shipping:\*\s+-\s+/', '*Shipping:* ', $message );

		// Remove empty section headings: a line that is only "*Heading:*" and is
		// followed by a blank line, by another "*Heading:*" line, or by the end of the message.
		// Other lines, such as "Hi! I'd like to order:" or "Note:", are never touched.
		$message = preg_replace( '/^\*[^*\n]+:\*[ \t]*(?:\n\n+|\n+(?=\*[^*\n]+:\*))/m', '', $message );
		$message = preg_replace( '/(^|\n)\*[^*\n]+:\*\s*\z/', '', $message );

		// Remove excessive blank lines.
		$message = preg_replace( "/\n{3,}/", "\n\n", $message );

		// Trim.
		$message = trim( $message );

		return $message;
	}

	/**
	 * Truncate message if too long.
	 *
	 * @param string    $message Message.
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function truncate_message( $message, $order ) {
		$encoded_length = strlen( rawurlencode( $message ) );

		if ( $encoded_length <= self::MAX_LENGTH ) {
			return $message;
		}

		// Add truncation notice.
		$truncate_text = "\n\n" . sprintf(
			/* translators: %s: Order view URL */
			__( '...and more. See full details: %s', 'ordercourier' ),
			$order->get_view_order_url()
		);

		$available_length = self::MAX_LENGTH - strlen( rawurlencode( $truncate_text ) );

		// Binary search for the right length.
		$left  = 0;
		$right = strlen( $message );

		while ( $left < $right ) {
			$mid     = intval( ( $left + $right + 1 ) / 2 );
			$test    = substr( $message, 0, $mid );
			$encoded = strlen( rawurlencode( $test ) );

			if ( $encoded <= $available_length ) {
				$left = $mid;
			} else {
				$right = $mid - 1;
			}
		}

		$message = substr( $message, 0, $left ) . $truncate_text;

		return $message;
	}

	/**
	 * Build WhatsApp URL.
	 *
	 * @param string $phone Phone number.
	 * @param string $message Message.
	 * @return string
	 */
	public static function build_whatsapp_url( $phone, $message ) {
		$phone = Phone_Validator::normalize( $phone );
		$phone = str_replace( '+', '', $phone );

		return 'https://wa.me/' . $phone . '?text=' . rawurlencode( $message );
	}

	/**
	 * Format custom checkout fields for an order.
	 *
	 * @param \WC_Order $order Order object.
	 * @return string
	 */
	private static function format_checkout_fields( $order ) {
		$settings      = get_option( 'ordercourier_settings', array() );
		$fields_config = isset( $settings['custom_checkout_fields'] ) ? $settings['custom_checkout_fields'] : '';

		if ( empty( $fields_config ) ) {
			return '';
		}

		$lines         = explode( "\n", $fields_config );
		$fields_output = array();

		foreach ( $lines as $line ) {
			$line = trim( $line );
			if ( empty( $line ) ) {
				continue;
			}

			$parts = explode( '|', $line );
			if ( count( $parts ) !== 2 ) {
				continue;
			}

			$meta_key = trim( $parts[0] );
			$label    = trim( $parts[1] );

			if ( empty( $meta_key ) || empty( $label ) ) {
				continue;
			}

			$value = null;

			// Check if this is a WooCommerce Blocks additional field (format: namespace/field-id).
			if ( strpos( $meta_key, '/' ) !== false && class_exists( '\Automattic\WooCommerce\Blocks\Package' ) ) {
				try {
					$checkout_fields_service = \Automattic\WooCommerce\Blocks\Package::container()->get(
						\Automattic\WooCommerce\Blocks\Domain\Services\CheckoutFields::class
					);
					$value                   = $checkout_fields_service->get_field_from_object( $meta_key, $order, 'other' );
				} catch ( \Exception $e ) {
					continue;
				}
			}

			// Fallback to standard order meta if not found.
			if ( null === $value || '' === $value ) {
				$value = $order->get_meta( $meta_key, true );
			}

			if ( ! empty( $value ) ) {
				// Handle array values (checkboxes, multi-select).
				if ( is_array( $value ) ) {
					$value = implode( ', ', array_filter( array_map( 'wc_clean', $value ), 'is_scalar' ) );
				} elseif ( ! is_scalar( $value ) ) {
					continue;
				}
				$fields_output[] = $label . ': ' . $value;
			}
		}

		return ! empty( $fields_output ) ? implode( "\n", $fields_output ) : '';
	}
}