<?php
/**
 * WooCommerce Invoice Generator.
 *
 * Generates PDF invoices for WooCommerce orders.
 *
 * @package Magdev\WpBnb\Integration\WooCommerce
 */

declare( strict_types=1 );

namespace Magdev\WpBnb\Integration\WooCommerce;

use Magdev\WpBnb\PostTypes\Room;
use Magdev\WpBnb\Pricing\Calculator;
use Mpdf\Mpdf;

/**
 * Invoice Generator class.
 *
 * Creates PDF invoices for bookings using mPDF.
 */
final class InvoiceGenerator {

	/**
	 * Invoice storage directory relative to uploads.
	 */
	private const INVOICE_DIR = 'wp-bnb-invoices';

	/**
	 * Initialize invoice generator.
	 *
	 * @return void
	 */
	public static function init(): void {
		// Attach invoice to order emails.
		add_filter( 'woocommerce_email_attachments', array( self::class, 'attach_invoice_to_email' ), 10, 4 );

		// Add admin order action button.
		add_action( 'woocommerce_admin_order_actions_end', array( self::class, 'add_order_action_button' ) );

		// AJAX handler for invoice generation.
		add_action( 'wp_ajax_wp_bnb_generate_invoice', array( self::class, 'ajax_generate_invoice' ) );

		// Handle invoice download.
		add_action( 'init', array( self::class, 'handle_invoice_download' ) );
	}

	/**
	 * Generate invoice for an order.
	 *
	 * @param \WC_Order $order WooCommerce order.
	 * @return string|null Invoice file path or null on failure.
	 */
	public static function generate_invoice( \WC_Order $order ): ?string {
		/**
		 * Fires before generating an invoice.
		 *
		 * @param \WC_Order $order WooCommerce order.
		 */
		do_action( 'wp_bnb_wc_before_invoice_generate', $order );

		// Get or generate invoice number.
		$invoice_number = self::get_invoice_number( $order );

		// Get booking data.
		$booking_id = Manager::get_booking_for_order( $order );

		// Generate HTML content.
		$html = self::get_invoice_html( $order, $invoice_number, $booking_id );

		// Generate PDF.
		try {
			$temp_dir = get_temp_dir() . 'mpdf';
			if ( ! file_exists( $temp_dir ) ) {
				wp_mkdir_p( $temp_dir );
			}

			$mpdf = new Mpdf(
				array(
					'mode'          => 'utf-8',
					'format'        => 'A4',
					'margin_left'   => 15,
					'margin_right'  => 15,
					'margin_top'    => 15,
					'margin_bottom' => 20,
					'tempDir'       => $temp_dir,
				)
			);

			$mpdf->SetTitle( sprintf( 'Invoice %s', $invoice_number ) );
			$mpdf->SetAuthor( get_option( 'wp_bnb_business_name', get_bloginfo( 'name' ) ) );
			$mpdf->SetCreator( 'WP BnB' );

			$mpdf->WriteHTML( $html );

			// Save to file.
			$file_path = self::get_invoice_path( $order, $invoice_number );
			$mpdf->Output( $file_path, 'F' );

			// Store invoice number and path in order meta.
			$order->update_meta_data( '_bnb_invoice_number', $invoice_number );
			$order->update_meta_data( '_bnb_invoice_path', $file_path );
			$order->update_meta_data( '_bnb_invoice_date', current_time( 'mysql' ) );
			$order->save();

			/**
			 * Fires after generating an invoice.
			 *
			 * @param \WC_Order $order     WooCommerce order.
			 * @param string    $file_path Invoice file path.
			 */
			do_action( 'wp_bnb_wc_after_invoice_generate', $order, $file_path );

			return $file_path;

		} catch ( \Exception $e ) {
			error_log( 'WP BnB Invoice generation failed: ' . $e->getMessage() );
			return null;
		}
	}

	/**
	 * Get invoice number for an order.
	 *
	 * @param \WC_Order $order WooCommerce order.
	 * @return string Invoice number.
	 */
	public static function get_invoice_number( \WC_Order $order ): string {
		// Check if already has invoice number.
		$existing = $order->get_meta( '_bnb_invoice_number', true );

		if ( $existing ) {
			return $existing;
		}

		// Generate new invoice number.
		return Manager::get_next_invoice_number();
	}

	/**
	 * Get invoice file path.
	 *
	 * @param \WC_Order $order          WooCommerce order.
	 * @param string    $invoice_number Invoice number.
	 * @return string File path.
	 */
	private static function get_invoice_path( \WC_Order $order, string $invoice_number ): string {
		$upload_dir = wp_upload_dir();
		$invoice_dir = $upload_dir['basedir'] . '/' . self::INVOICE_DIR;

		// Create directory if needed.
		if ( ! file_exists( $invoice_dir ) ) {
			wp_mkdir_p( $invoice_dir );

			// Add .htaccess to protect invoices.
			$htaccess = $invoice_dir . '/.htaccess';
			if ( ! file_exists( $htaccess ) ) {
				file_put_contents( $htaccess, 'Deny from all' );
			}

			// Add index.php for extra protection.
			$index = $invoice_dir . '/index.php';
			if ( ! file_exists( $index ) ) {
				file_put_contents( $index, '<?php // Silence is golden.' );
			}
		}

		// Sanitize invoice number for filename.
		$safe_number = sanitize_file_name( $invoice_number );

		return $invoice_dir . '/invoice-' . $safe_number . '-' . $order->get_id() . '.pdf';
	}

	/**
	 * Check if invoice exists for an order.
	 *
	 * @param \WC_Order $order WooCommerce order.
	 * @return bool
	 */
	public static function invoice_exists( \WC_Order $order ): bool {
		$path = $order->get_meta( '_bnb_invoice_path', true );

		return $path && file_exists( $path );
	}

	/**
	 * Attach invoice to email.
	 *
	 * @param array      $attachments Attachments array.
	 * @param string     $email_id    Email ID.
	 * @param \WC_Order  $order       WooCommerce order.
	 * @param \WC_Email  $email       Email object.
	 * @return array Modified attachments.
	 */
	public static function attach_invoice_to_email( array $attachments, string $email_id, $order, $email ): array {
		// Only attach to specific emails.
		$allowed_emails = array(
			'customer_completed_order',
			'customer_processing_order',
			'customer_invoice',
		);

		if ( ! in_array( $email_id, $allowed_emails, true ) ) {
			return $attachments;
		}

		// Check if order is a WC_Order.
		if ( ! $order instanceof \WC_Order ) {
			return $attachments;
		}

		// Check if invoice attachment is enabled.
		if ( ! Manager::is_invoice_attach_enabled() ) {
			return $attachments;
		}

		// Check if this order has a booking.
		$booking_id = Manager::get_booking_for_order( $order );

		if ( ! $booking_id ) {
			return $attachments;
		}

		// Generate invoice if it doesn't exist.
		if ( ! self::invoice_exists( $order ) ) {
			self::generate_invoice( $order );
		}

		// Get invoice path.
		$invoice_path = $order->get_meta( '_bnb_invoice_path', true );

		if ( $invoice_path && file_exists( $invoice_path ) ) {
			$attachments[] = $invoice_path;
		}

		return $attachments;
	}

	/**
	 * Add order action button for invoice.
	 *
	 * @param \WC_Order $order WooCommerce order.
	 * @return void
	 */
	public static function add_order_action_button( \WC_Order $order ): void {
		// Check if this order has a booking.
		$booking_id = Manager::get_booking_for_order( $order );

		if ( ! $booking_id ) {
			return;
		}

		// Generate download URL.
		$download_url = add_query_arg(
			array(
				'bnb_download_invoice' => $order->get_id(),
				'_wpnonce'             => wp_create_nonce( 'bnb_download_invoice_' . $order->get_id() ),
			),
			admin_url( 'admin.php' )
		);

		?>
		<a class="button tips" href="<?php echo esc_url( $download_url ); ?>"
		   data-tip="<?php esc_attr_e( 'Download Invoice', 'wp-bnb' ); ?>">
			<span class="dashicons dashicons-pdf" style="vertical-align: middle;"></span>
		</a>
		<?php
	}

	/**
	 * AJAX handler for generating invoice.
	 *
	 * @return void
	 */
	public static function ajax_generate_invoice(): void {
		check_ajax_referer( 'wp_bnb_admin_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_woocommerce' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied.', 'wp-bnb' ) ) );
		}

		$order_id = isset( $_POST['order_id'] ) ? absint( $_POST['order_id'] ) : 0;

		if ( ! $order_id ) {
			wp_send_json_error( array( 'message' => __( 'Invalid order ID.', 'wp-bnb' ) ) );
		}

		$order = wc_get_order( $order_id );

		if ( ! $order ) {
			wp_send_json_error( array( 'message' => __( 'Order not found.', 'wp-bnb' ) ) );
		}

		$file_path = self::generate_invoice( $order );

		if ( $file_path ) {
			wp_send_json_success( array( 'message' => __( 'Invoice generated successfully.', 'wp-bnb' ) ) );
		} else {
			wp_send_json_error( array( 'message' => __( 'Failed to generate invoice.', 'wp-bnb' ) ) );
		}
	}

	/**
	 * Handle invoice download request.
	 *
	 * @return void
	 */
	public static function handle_invoice_download(): void {
		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
		if ( ! isset( $_GET['bnb_download_invoice'] ) ) {
			return;
		}

		$order_id = absint( $_GET['bnb_download_invoice'] );

		// Verify nonce.
		if ( ! isset( $_GET['_wpnonce'] ) || ! wp_verify_nonce( sanitize_key( $_GET['_wpnonce'] ), 'bnb_download_invoice_' . $order_id ) ) {
			wp_die( esc_html__( 'Security check failed.', 'wp-bnb' ) );
		}

		// Check capabilities.
		if ( ! current_user_can( 'manage_woocommerce' ) ) {
			wp_die( esc_html__( 'You do not have permission to download invoices.', 'wp-bnb' ) );
		}

		$order = wc_get_order( $order_id );

		if ( ! $order ) {
			wp_die( esc_html__( 'Order not found.', 'wp-bnb' ) );
		}

		// Generate invoice if needed.
		if ( ! self::invoice_exists( $order ) ) {
			self::generate_invoice( $order );
		}

		$invoice_path = $order->get_meta( '_bnb_invoice_path', true );

		if ( ! $invoice_path || ! file_exists( $invoice_path ) ) {
			wp_die( esc_html__( 'Invoice not found.', 'wp-bnb' ) );
		}

		$invoice_number = $order->get_meta( '_bnb_invoice_number', true );
		$filename       = 'invoice-' . sanitize_file_name( $invoice_number ) . '.pdf';

		// Output file.
		header( 'Content-Type: application/pdf' );
		header( 'Content-Disposition: attachment; filename="' . $filename . '"' );
		header( 'Content-Length: ' . filesize( $invoice_path ) );
		header( 'Cache-Control: no-cache, no-store, must-revalidate' );

		readfile( $invoice_path );
		exit;
	}

	/**
	 * Get invoice HTML content.
	 *
	 * @param \WC_Order $order          WooCommerce order.
	 * @param string    $invoice_number Invoice number.
	 * @param int|null  $booking_id     Booking ID.
	 * @return string HTML content.
	 */
	private static function get_invoice_html( \WC_Order $order, string $invoice_number, ?int $booking_id ): string {
		// Get business info.
		$business = self::get_business_info();

		// Get booking details.
		$check_in  = '';
		$check_out = '';
		$room_name = '';
		$building_name = '';
		$nights    = 0;
		$guests    = 0;

		if ( $booking_id ) {
			$check_in  = get_post_meta( $booking_id, '_bnb_booking_check_in', true );
			$check_out = get_post_meta( $booking_id, '_bnb_booking_check_out', true );
			$guests    = get_post_meta( $booking_id, '_bnb_booking_adults', true );
			$room_id   = get_post_meta( $booking_id, '_bnb_booking_room_id', true );

			if ( $room_id ) {
				$room = get_post( $room_id );
				$room_name = $room ? $room->post_title : '';
				$building = Room::get_building( $room_id );
				$building_name = $building ? $building->post_title : '';
			}

			if ( $check_in && $check_out ) {
				$check_in_date  = \DateTime::createFromFormat( 'Y-m-d', $check_in );
				$check_out_date = \DateTime::createFromFormat( 'Y-m-d', $check_out );
				if ( $check_in_date && $check_out_date ) {
					$nights = $check_in_date->diff( $check_out_date )->days;
				}
			}
		}

		// Format dates.
		$date_format       = get_option( 'date_format' );
		$check_in_display  = $check_in ? date_i18n( $date_format, strtotime( $check_in ) ) : '';
		$check_out_display = $check_out ? date_i18n( $date_format, strtotime( $check_out ) ) : '';
		$order_date        = $order->get_date_created() ? $order->get_date_created()->date_i18n( $date_format ) : '';

		// Get logo.
		$logo_html = '';
		$logo_id   = Manager::get_invoice_logo();
		if ( $logo_id ) {
			$logo_url = wp_get_attachment_url( $logo_id );
			if ( $logo_url ) {
				$logo_html = '<img src="' . esc_url( $logo_url ) . '" style="max-height: 60px; max-width: 200px;">';
			}
		}

		// Get footer.
		$footer_text = Manager::get_invoice_footer();

		// Build HTML.
		$html = '<html><head><style>' . self::get_invoice_css() . '</style></head><body>';

		// Header.
		$html .= '<div class="invoice-header">';
		$html .= '<div class="logo">' . $logo_html . '</div>';
		$html .= '<div class="invoice-title">';
		$html .= '<h1>' . esc_html__( 'INVOICE', 'wp-bnb' ) . '</h1>';
		$html .= '<p class="invoice-number">' . esc_html( $invoice_number ) . '</p>';
		$html .= '<p class="invoice-date">' . esc_html( $order_date ) . '</p>';
		$html .= '</div>';
		$html .= '</div>';

		// Addresses.
		$html .= '<div class="addresses">';

		// From.
		$html .= '<div class="address from">';
		$html .= '<h3>' . esc_html__( 'From', 'wp-bnb' ) . '</h3>';
		$html .= '<p><strong>' . esc_html( $business['name'] ) . '</strong></p>';
		if ( $business['street'] ) {
			$html .= '<p>' . esc_html( $business['street'] ) . '</p>';
		}
		if ( $business['city'] || $business['postal'] ) {
			$html .= '<p>' . esc_html( $business['postal'] . ' ' . $business['city'] ) . '</p>';
		}
		if ( $business['country'] ) {
			$html .= '<p>' . esc_html( $business['country'] ) . '</p>';
		}
		if ( $business['email'] ) {
			$html .= '<p>' . esc_html( $business['email'] ) . '</p>';
		}
		if ( $business['phone'] ) {
			$html .= '<p>' . esc_html( $business['phone'] ) . '</p>';
		}
		$html .= '</div>';

		// To.
		$html .= '<div class="address to">';
		$html .= '<h3>' . esc_html__( 'Bill To', 'wp-bnb' ) . '</h3>';
		$html .= '<p><strong>' . esc_html( $order->get_billing_first_name() . ' ' . $order->get_billing_last_name() ) . '</strong></p>';
		if ( $order->get_billing_address_1() ) {
			$html .= '<p>' . esc_html( $order->get_billing_address_1() ) . '</p>';
		}
		if ( $order->get_billing_city() || $order->get_billing_postcode() ) {
			$html .= '<p>' . esc_html( $order->get_billing_postcode() . ' ' . $order->get_billing_city() ) . '</p>';
		}
		if ( $order->get_billing_country() ) {
			$html .= '<p>' . esc_html( WC()->countries->countries[ $order->get_billing_country() ] ?? $order->get_billing_country() ) . '</p>';
		}
		if ( $order->get_billing_email() ) {
			$html .= '<p>' . esc_html( $order->get_billing_email() ) . '</p>';
		}
		$html .= '</div>';
		$html .= '</div>';

		// Booking details.
		if ( $booking_id && $room_name ) {
			$html .= '<div class="booking-details">';
			$html .= '<h3>' . esc_html__( 'Booking Details', 'wp-bnb' ) . '</h3>';
			$html .= '<table class="details-table">';
			$html .= '<tr><td><strong>' . esc_html__( 'Room', 'wp-bnb' ) . '</strong></td><td>' . esc_html( $room_name );
			if ( $building_name ) {
				$html .= ' <small>(' . esc_html( $building_name ) . ')</small>';
			}
			$html .= '</td></tr>';
			$html .= '<tr><td><strong>' . esc_html__( 'Check-in', 'wp-bnb' ) . '</strong></td><td>' . esc_html( $check_in_display ) . '</td></tr>';
			$html .= '<tr><td><strong>' . esc_html__( 'Check-out', 'wp-bnb' ) . '</strong></td><td>' . esc_html( $check_out_display ) . '</td></tr>';
			$html .= '<tr><td><strong>' . esc_html__( 'Nights', 'wp-bnb' ) . '</strong></td><td>' . esc_html( $nights ) . '</td></tr>';
			$html .= '<tr><td><strong>' . esc_html__( 'Guests', 'wp-bnb' ) . '</strong></td><td>' . esc_html( $guests ) . '</td></tr>';
			$html .= '</table>';
			$html .= '</div>';
		}

		// Line items.
		$html .= '<div class="line-items">';
		$html .= '<table class="items-table">';
		$html .= '<thead><tr>';
		$html .= '<th class="description">' . esc_html__( 'Description', 'wp-bnb' ) . '</th>';
		$html .= '<th class="qty">' . esc_html__( 'Qty', 'wp-bnb' ) . '</th>';
		$html .= '<th class="price">' . esc_html__( 'Price', 'wp-bnb' ) . '</th>';
		$html .= '<th class="total">' . esc_html__( 'Total', 'wp-bnb' ) . '</th>';
		$html .= '</tr></thead>';
		$html .= '<tbody>';

		foreach ( $order->get_items() as $item ) {
			$qty   = $item->get_quantity();
			$total = $item->get_total();
			$price = $qty > 0 ? $total / $qty : $total;

			$html .= '<tr>';
			$html .= '<td class="description">' . esc_html( $item->get_name() ) . '</td>';
			$html .= '<td class="qty">' . esc_html( $qty ) . '</td>';
			$html .= '<td class="price">' . wc_price( $price ) . '</td>';
			$html .= '<td class="total">' . wc_price( $total ) . '</td>';
			$html .= '</tr>';
		}

		$html .= '</tbody>';
		$html .= '</table>';
		$html .= '</div>';

		// Totals.
		$html .= '<div class="totals">';
		$html .= '<table class="totals-table">';
		$html .= '<tr><td>' . esc_html__( 'Subtotal', 'wp-bnb' ) . '</td><td>' . wc_price( $order->get_subtotal() ) . '</td></tr>';

		if ( $order->get_total_tax() > 0 ) {
			$html .= '<tr><td>' . esc_html__( 'Tax', 'wp-bnb' ) . '</td><td>' . wc_price( $order->get_total_tax() ) . '</td></tr>';
		}

		$html .= '<tr class="grand-total"><td><strong>' . esc_html__( 'Total', 'wp-bnb' ) . '</strong></td><td><strong>' . wc_price( $order->get_total() ) . '</strong></td></tr>';
		$html .= '</table>';
		$html .= '</div>';

		// Payment info.
		$html .= '<div class="payment-info">';
		$html .= '<p><strong>' . esc_html__( 'Payment Status:', 'wp-bnb' ) . '</strong> ';

		if ( $order->is_paid() ) {
			$html .= '<span class="paid">' . esc_html__( 'PAID', 'wp-bnb' ) . '</span>';
		} else {
			$html .= '<span class="unpaid">' . esc_html__( 'PENDING', 'wp-bnb' ) . '</span>';
		}

		$html .= '</p>';
		$html .= '<p><strong>' . esc_html__( 'Payment Method:', 'wp-bnb' ) . '</strong> ' . esc_html( $order->get_payment_method_title() ) . '</p>';
		$html .= '</div>';

		// Footer.
		$html .= '<div class="footer">';
		$html .= '<p>' . esc_html__( 'Thank you for your stay!', 'wp-bnb' ) . '</p>';
		if ( $footer_text ) {
			$html .= '<p class="custom-footer">' . esc_html( $footer_text ) . '</p>';
		}
		$html .= '</div>';

		$html .= '</body></html>';

		/**
		 * Filter the invoice HTML.
		 *
		 * @param string    $html  Invoice HTML.
		 * @param \WC_Order $order WooCommerce order.
		 */
		return apply_filters( 'wp_bnb_wc_invoice_html', $html, $order );
	}

	/**
	 * Get invoice CSS styles.
	 *
	 * @return string CSS content.
	 */
	private static function get_invoice_css(): string {
		return '
			body { font-family: DejaVu Sans, sans-serif; font-size: 10pt; color: #333; line-height: 1.4; }
			h1 { font-size: 24pt; color: #2271b1; margin: 0; text-align: right; }
			h3 { font-size: 11pt; color: #50575e; margin: 15pt 0 5pt 0; }

			.invoice-header { margin-bottom: 30pt; overflow: hidden; }
			.logo { float: left; width: 50%; }
			.invoice-title { float: right; width: 50%; text-align: right; }
			.invoice-number { font-size: 14pt; font-weight: bold; color: #333; margin: 5pt 0; }
			.invoice-date { font-size: 10pt; color: #787c82; margin: 0; }

			.addresses { margin-bottom: 20pt; overflow: hidden; }
			.address { width: 48%; }
			.address.from { float: left; }
			.address.to { float: right; }
			.address p { margin: 2pt 0; font-size: 9pt; }

			.booking-details { margin-bottom: 20pt; background: #f9f9f9; padding: 10pt; border-radius: 4pt; }
			.details-table { width: 100%; border-collapse: collapse; }
			.details-table td { padding: 4pt 8pt; font-size: 9pt; border-bottom: 1px solid #e1e4e8; }
			.details-table td:first-child { width: 120pt; }

			.line-items { margin-bottom: 20pt; }
			.items-table { width: 100%; border-collapse: collapse; }
			.items-table th { background: #f6f7f7; text-align: left; padding: 8pt; font-size: 9pt; border-bottom: 2px solid #c3c4c7; }
			.items-table td { padding: 8pt; font-size: 9pt; border-bottom: 1px solid #e1e4e8; }
			.items-table .qty, .items-table .price, .items-table .total { text-align: right; width: 70pt; }

			.totals { margin-bottom: 20pt; }
			.totals-table { width: 250pt; margin-left: auto; border-collapse: collapse; }
			.totals-table td { padding: 6pt 8pt; font-size: 10pt; }
			.totals-table td:last-child { text-align: right; }
			.totals-table .grand-total td { border-top: 2px solid #333; font-size: 12pt; }

			.payment-info { margin-bottom: 30pt; padding: 10pt; background: #f9f9f9; border-radius: 4pt; }
			.payment-info p { margin: 4pt 0; font-size: 9pt; }
			.payment-info .paid { color: #00a32a; font-weight: bold; }
			.payment-info .unpaid { color: #dba617; font-weight: bold; }

			.footer { text-align: center; margin-top: 40pt; padding-top: 15pt; border-top: 1px solid #c3c4c7; }
			.footer p { font-size: 9pt; color: #787c82; margin: 3pt 0; }
			.custom-footer { font-size: 8pt; }
		';
	}

	/**
	 * Get business information from settings.
	 *
	 * @return array Business info.
	 */
	private static function get_business_info(): array {
		return array(
			'name'    => get_option( 'wp_bnb_business_name', get_bloginfo( 'name' ) ),
			'street'  => get_option( 'wp_bnb_address_street', '' ),
			'city'    => get_option( 'wp_bnb_address_city', '' ),
			'postal'  => get_option( 'wp_bnb_address_postal', '' ),
			'country' => get_option( 'wp_bnb_address_country', '' ),
			'email'   => get_option( 'wp_bnb_contact_email', get_option( 'admin_email' ) ),
			'phone'   => get_option( 'wp_bnb_contact_phone', '' ),
		);
	}
}