<?php
/**
 * What makes publishing a post also publish it to the name.
 *
 * Everything hangs off `transition_post_status`, which fires for every way a
 * post can change state — the editor, quick edit, a scheduled publish firing
 * from cron, the REST API, WP-CLI, an importer. Hooking `save_post` instead
 * would miss the scheduled case, which is exactly the case a site owner most
 * expects to work while they are asleep.
 *
 * Unpublishing is handled too, and it matters more than it looks: a static
 * mirror that keeps serving a post the author deleted is worse than no mirror,
 * because the author believes the page is gone.
 *
 * @package SiriusPress
 */

defined( 'ABSPATH' ) || exit;

final class SPE_Hooks {

	public static function hooks() {
		add_action( 'transition_post_status', array( __CLASS__, 'on_transition' ), 10, 3 );
		add_action( 'before_delete_post', array( __CLASS__, 'on_delete' ), 10, 2 );
		add_action( 'edited_term', array( __CLASS__, 'on_term_edited' ), 10, 3 );
	}

	/**
	 * @param string  $new_status
	 * @param string  $old_status
	 * @param WP_Post $post
	 */
	public static function on_transition( $new_status, $old_status, $post ) {
		if ( ! self::should_export( $post ) ) {
			return;
		}

		// Went from public to not — take the file down before refreshing the
		// pages that used to link to it.
		if ( 'publish' === $old_status && 'publish' !== $new_status ) {
			$path = SPE_Mapper::path_for_post( $post );
			if ( '' !== $path ) {
				self::unpublish( $path );
			}
		}

		if ( 'publish' !== $new_status && 'publish' !== $old_status ) {
			return; // A draft being edited changes nothing anyone can see.
		}

		foreach ( SPE_Mapper::affected_by_post( $post ) as $path => $target ) {
			SPE_Queue::add( $path, $target['url'], $target['kind'] );
		}
	}

	public static function on_delete( $post_id, $post = null ) {
		$post = $post ? $post : get_post( $post_id );
		if ( ! $post || ! self::should_export( $post ) || 'publish' !== $post->post_status ) {
			return;
		}
		$path = SPE_Mapper::path_for_post( $post );
		if ( '' !== $path ) {
			self::unpublish( $path );
		}
		foreach ( SPE_Mapper::affected_by_post( $post ) as $affected => $target ) {
			if ( $affected !== $path ) {
				SPE_Queue::add( $affected, $target['url'], $target['kind'] );
			}
		}
	}

	/** Renaming a category changes its archive URL and every page linking to it. */
	public static function on_term_edited( $term_id, $tt_id, $taxonomy ) {
		if ( ! SP_Settings::auto_publish() ) {
			return;
		}
		$tax = get_taxonomy( $taxonomy );
		if ( ! $tax || ! $tax->public ) {
			return;
		}
		$link = get_term_link( (int) $term_id, $taxonomy );
		if ( is_wp_error( $link ) ) {
			return;
		}
		$path = SPE_Mapper::path_for_url_path( (string) wp_parse_url( $link, PHP_URL_PATH ) );
		if ( '' !== $path ) {
			SPE_Queue::add( $path, $link, 'archive' );
		}
	}

	private static function should_export( $post ) {
		if ( ! SP_Settings::auto_publish() || ! SP_Settings::is_configured() ) {
			return false;
		}
		if ( ! $post instanceof WP_Post ) {
			return false;
		}
		if ( wp_is_post_revision( $post ) || wp_is_post_autosave( $post ) ) {
			return false;
		}
		$type = get_post_type_object( $post->post_type );
		if ( ! $type || ! $type->public ) {
			return false;
		}
		// A password-protected post renders as a password form to the
		// exporter, and publishing that form to permanent public storage
		// would be worse than not publishing at all.
		if ( '' !== $post->post_password ) {
			return false;
		}
		/**
		 * Filters whether a post is exported at all.
		 *
		 * @param bool    $export
		 * @param WP_Post $post
		 */
		return (bool) apply_filters( 'sirius_press_should_export_post', true, $post );
	}

	/**
	 * Remove a path from the bucket.
	 *
	 * In manual mode there is no key to sign a delete with, so the operator is
	 * told rather than left with a stale page they think is gone.
	 */
	private static function unpublish( $path ) {
		if ( SP_Settings::MODE_SERVER !== SP_Settings::mode() ) {
			SP_Inbox::add(
				0,
				__( 'A removed page is still published to your name', 'sirius-press' ),
				sprintf(
					/* translators: 1: bucket path, 2: export screen URL. */
					wp_kses_post( __( '<code>%1$s</code> is no longer public on this site, but this server holds no key to delete it from the name\'s storage. <a href="%2$s">Remove it from the export screen</a>.', 'sirius-press' ) ),
					esc_html( $path ),
					esc_url( admin_url( 'admin.php?page=sirius-press-export' ) )
				),
				'export'
			);
			return;
		}
		$result = SP_Gateway::delete( $path );
		if ( empty( $result['ok'] ) ) {
			SP_Inbox::add(
				0,
				__( 'A removed page could not be unpublished', 'sirius-press' ),
				sprintf(
					/* translators: 1: bucket path, 2: error message. */
					wp_kses_post( __( '<code>%1$s</code> could not be deleted from the name\'s storage: %2$s', 'sirius-press' ) ),
					esc_html( $path ),
					esc_html( $result['error'] )
				),
				'export'
			);
		}
	}
}