<?php
/**
 * Dual-context Promo Risk presentation (PRD 10.4).
 *
 * @package Kayvandra\MarginBeacon
 */

declare(strict_types=1);

namespace Kayvandra\MarginBeacon\Admin\Orders;

use Kayvandra\MarginBeacon\Application\OrderRisk\FreeShippingScope;
use Kayvandra\MarginBeacon\Domain\Risk\Severity;

/**
 * Builds short dual-context copy for badges and detail panels.
 */
final class DualContextPresenter {

	/**
	 * Extract dual-context payload from a risk row.
	 *
	 * @param array $row Order risk row.
	 * @return array{order_severity:?string,line_severity:?string,loss_making_lines:int,summary:string}
	 */
	public static function from_row( array $row ) {
		$coverage = array();
		if ( ! empty( $row['coverage_json'] ) ) {
			$decoded = json_decode( (string) $row['coverage_json'], true );
			if ( is_array( $decoded ) ) {
				$coverage = $decoded;
			}
		}

		$dual = isset( $coverage['dual_context'] ) && is_array( $coverage['dual_context'] )
			? $coverage['dual_context']
			: array();

		$order_sev = isset( $dual['order_severity'] ) ? (string) $dual['order_severity'] : ( $row['risk_badge'] ? (string) $row['risk_badge'] : null );
		$line_sev  = isset( $dual['line_severity'] ) ? (string) $dual['line_severity'] : $order_sev;
		$loss      = isset( $dual['loss_making_lines'] ) ? (int) $dual['loss_making_lines'] : 0;

		return array(
			'order_severity'    => $order_sev,
			'line_severity'     => $line_sev,
			'loss_making_lines' => $loss,
			'summary'           => self::summary( $order_sev, $line_sev, $loss, $coverage ),
		);
	}

	/**
	 * Human-readable dual-context line.
	 *
	 * @param string|null $order_sev Order-level severity.
	 * @param string|null $line_sev  Worst line severity.
	 * @param int         $loss      Loss-making line count.
	 * @param array       $coverage  Optional coverage flags.
	 * @return string
	 */
	public static function summary( $order_sev, $line_sev, $loss = 0, array $coverage = array() ) {
		if ( ! $order_sev && ! $line_sev ) {
			return '';
		}

		if ( FreeShippingScope::coverage_excludes_shipping( $coverage )
			&& 'safe' === $order_sev
			&& ( ! $line_sev || 'safe' === $line_sev )
		) {
			return FreeShippingScope::safe_label();
		}

		$order_label = $order_sev ? Severity::label( $order_sev ) : '—';
		$line_label  = $line_sev ? Severity::label( $line_sev ) : '—';
		$fully       = isset( $coverage['fully_discounted_lines'] ) ? (int) $coverage['fully_discounted_lines'] : 0;

		// PRD 10.4 / 12.8.3 — free-gift dual-context copy.
		if ( $fully > 0
			&& $order_sev
			&& $line_sev
			&& $order_sev !== $line_sev
			&& Severity::CRITICAL === $line_sev
		) {
			return sprintf(
				/* translators: 1: order severity, 2: line severity */
				__( 'Order margin: %1$s · Line risk: %2$s — intentional free gift', 'marginbeacon' ),
				$order_label,
				$line_label
			);
		}

		if ( $order_sev && $line_sev && $order_sev === $line_sev ) {
			if ( $fully > 0 && Severity::CRITICAL === $line_sev ) {
				return sprintf(
					/* translators: 1: severity, 2: count */
					_n(
						'Order & line risk: %1$s — %2$d fully discounted item',
						'Order & line risk: %1$s — %2$d fully discounted items',
						$fully,
						'marginbeacon'
					),
					$order_label,
					$fully
				);
			}
			if ( $loss > 1 ) {
				return sprintf(
					/* translators: 1: severity, 2: count */
					__( 'Order & line risk: %1$s — %2$d items below cost', 'marginbeacon' ),
					$order_label,
					$loss
				);
			}
			return sprintf(
				/* translators: %s: severity */
				__( 'Order & line risk: %s', 'marginbeacon' ),
				$order_label
			);
		}

		$extra = '';
		if ( $fully > 0 && Severity::CRITICAL === $line_sev ) {
			$extra = ' — ' . __( 'intentional free gift', 'marginbeacon' );
		} elseif ( $loss > 0 && $line_sev && in_array( $line_sev, array( Severity::CRITICAL, Severity::HIGH, Severity::WARNING ), true ) ) {
			$extra = sprintf(
				/* translators: %d: count */
				_n( ' — %d loss-making item', ' — %d loss-making items', $loss, 'marginbeacon' ),
				$loss
			);
		}

		return sprintf(
			/* translators: 1: order severity, 2: line severity, 3: optional suffix */
			__( 'Order margin: %1$s · Line risk: %2$s%3$s', 'marginbeacon' ),
			$order_label,
			$line_label,
			$extra
		);
	}
}