<?php
/**
 * Handlers for the mapping screens: saving the category map, refreshing the category list, and the
 * live search and suggestions (admin-ajax). They change only the plugin's own settings and cache.
 *
 * @package Tidelist
 */

namespace Tidelist\Admin;

use Tidelist\Channel\Exception\ChannelException;
use Tidelist\Jobs\LoadCategories;
use Tidelist\Mapping\AttributeRule;
use Tidelist\Mapping\CategoryMap;
use Tidelist\Plugin;
use Tidelist\Support\Text;

/**
 * Mapping handlers.
 */
final class MappingActions {

	const SAVE_CATEGORIES    = 'tidelist_category_map_save';
	const SAVE_ATTRIBUTES    = 'tidelist_attribute_map_save';
	const REFRESH_CATEGORIES = 'tidelist_categories_refresh';
	const AJAX_SEARCH        = 'tidelist_category_search';
	const AJAX_SUGGEST       = 'tidelist_category_suggest';

	/**
	 * Plugin.
	 *
	 * @var Plugin
	 */
	private $plugin;

	/**
	 * Constructor.
	 *
	 * @param Plugin $plugin Plugin.
	 */
	public function __construct( Plugin $plugin ) {
		$this->plugin = $plugin;
	}

	/**
	 * Registers the handlers.
	 */
	public function register(): void {
		add_action( 'admin_post_' . self::SAVE_CATEGORIES, array( $this, 'save_categories' ) );
		add_action( 'admin_post_' . self::SAVE_ATTRIBUTES, array( $this, 'save_attributes' ) );
		add_action( 'admin_post_' . self::REFRESH_CATEGORIES, array( $this, 'refresh_categories' ) );
		add_action( 'wp_ajax_' . self::AJAX_SEARCH, array( $this, 'ajax_search' ) );
		add_action( 'wp_ajax_' . self::AJAX_SUGGEST, array( $this, 'ajax_suggest' ) );
	}

	/**
	 * Saves the category map.
	 */
	public function save_categories(): void {
		$this->guard( self::SAVE_CATEGORIES );
		$channel_label = $this->plugin->requested_channel()->label();
		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized, WordPress.Security.NonceVerification.Missing -- nonce checked in guard(); values cast to integers below.
		$posted  = isset( $_POST['tidelist_map'] ) && is_array( $_POST['tidelist_map'] ) ? wp_unslash( $_POST['tidelist_map'] ) : array();
		$channel = $this->plugin->requested_channel();
		$map     = $this->plugin->category_map( $channel->id() );
		$tree    = $channel->taxonomy()->index();
		$skipped = 0;
		foreach ( $posted as $wc_id => $remote_id ) {
			$wc_id     = absint( $wc_id );
			$remote_id = absint( $remote_id );
			if ( $remote_id > 0 && $tree->count() > 0 && ! $tree->is_leaf( $remote_id ) ) {
				++$skipped; // Marketplaces take adverts in the last level of their tree only.
				continue;
			}
			$map->set( $wc_id, $remote_id );
		}
		$settings = $this->plugin->settings();
		$settings->update( array( 'category_map' => $map->to_setting( (array) $settings->get( 'category_map' ), $channel->id() ) ) );
		Flash::add( 'success', __( 'Category mapping saved.', 'tidelist' ) );
		if ( $skipped ) {
			/* translators: %d: number of categories */
			Flash::add( 'warning', sprintf( Text::channel( __( '%d choices were not saved because they are not in the last level of the {channel} categories.', 'tidelist' ), $channel_label ), $skipped ) );
		}
		$this->back();
	}

	/**
	 * Saves the attribute rules of one marketplace category.
	 */
	public function save_attributes(): void {
		$this->guard( self::SAVE_ATTRIBUTES );
		$channel = $this->plugin->requested_channel();
		// phpcs:disable WordPress.Security.ValidatedSanitizedInput.InputNotSanitized, WordPress.Security.NonceVerification.Missing -- nonce checked in guard(); every value is sanitized below.
		$cat    = isset( $_POST['remote_cat'] ) ? absint( $_POST['remote_cat'] ) : 0;
		$posted = isset( $_POST['tidelist_attr'] ) && is_array( $_POST['tidelist_attr'] ) ? wp_unslash( $_POST['tidelist_attr'] ) : array();
		// phpcs:enable
		if ( ! $cat ) {
			$this->back_to( Menu::attributes_url( 0, $channel->id() ) );
		}
		$map   = $this->plugin->attribute_map( $channel->id() );
		$known = array_column( $channel->taxonomy()->attributes( $cat ), 'code' );
		$map->clear_category( $cat );
		foreach ( $posted as $code => $data ) {
			$code = sanitize_text_field( (string) $code );
			if ( ! is_array( $data ) || ( $known && ! in_array( $code, $known, true ) ) ) {
				continue;
			}
			$source = AttributeMappingPage::parse_source( sanitize_text_field( (string) ( $data['source'] ?? 'skip' ) ) );
			$values = array();
			$terms  = isset( $data['terms'] ) && is_array( $data['terms'] ) ? $data['terms'] : array();
			$mapped = isset( $data['mapped'] ) && is_array( $data['mapped'] ) ? $data['mapped'] : array();
			foreach ( $terms as $i => $term ) {
				$chosen = sanitize_text_field( (string) ( $mapped[ $i ] ?? '' ) );
				if ( '' !== $chosen ) {
					$values[ sanitize_text_field( (string) $term ) ] = $chosen;
				}
			}
			$map->set_rule(
				$cat,
				$code,
				new AttributeRule(
					array(
						'type'   => $source['type'],
						'key'    => $source['key'],
						'fixed'  => sanitize_text_field( (string) ( $data['fixed'] ?? '' ) ),
						'values' => $values,
					)
				)
			);
		}
		$settings = $this->plugin->settings();
		$settings->update( array( 'attribute_map' => $map->to_setting( (array) $settings->get( 'attribute_map' ), $channel->id() ) ) );
		Flash::add( 'success', __( 'Attribute mapping saved.', 'tidelist' ) );
		$this->back_to( Menu::attributes_url( $cat, $channel->id() ) );
	}

	/**
	 * Starts a background refresh of the marketplace category list.
	 */
	public function refresh_categories(): void {
		$this->guard( self::REFRESH_CATEGORIES );
		$channel       = $this->plugin->requested_channel();
		$channel_label = $channel->label();
		( new LoadCategories( $this->plugin ) )->start( $channel->id() );
		Flash::add( 'success', Text::channel( __( 'Loading the {channel} categories in the background. This takes a few minutes; reload this page to see the progress.', 'tidelist' ), $channel_label ) );
		$this->back();
	}

	/**
	 * Live search in the marketplace categories (leaf categories only).
	 */
	public function ajax_search(): void {
		$this->ajax_guard( self::AJAX_SEARCH );
		$query = isset( $_GET['q'] ) ? sanitize_text_field( wp_unslash( $_GET['q'] ) ) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- nonce checked in ajax_guard().
		wp_send_json_success( array( 'items' => $this->plugin->requested_channel()->taxonomy()->index()->search( $query, 15 ) ) );
	}

	/**
	 * The marketplace's own category suggestions for a title (a read-only call).
	 */
	public function ajax_suggest(): void {
		$this->ajax_guard( self::AJAX_SUGGEST );
		$title = isset( $_GET['q'] ) ? sanitize_text_field( wp_unslash( $_GET['q'] ) ) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- nonce checked in ajax_guard().
		try {
			$items = $this->plugin->requested_channel()->taxonomy()->suggest( $title );
		} catch ( ChannelException $e ) {
			wp_send_json_error( array( 'message' => $e->getMessage() ) );
		}
		wp_send_json_success( array( 'items' => $items ) );
	}

	/**
	 * Capability and nonce check for a form handler.
	 *
	 * @param string $action Action (also the nonce action).
	 */
	private function guard( string $action ): void {
		if ( ! current_user_can( Plugin::CAPABILITY ) ) {
			wp_die( esc_html__( 'You are not allowed to do this.', 'tidelist' ), '', array( 'response' => 403 ) );
		}
		check_admin_referer( $action );
	}

	/**
	 * Capability and nonce check for an ajax handler.
	 *
	 * @param string $action Nonce action.
	 */
	private function ajax_guard( string $action ): void {
		if ( ! current_user_can( Plugin::CAPABILITY ) ) {
			wp_send_json_error( array( 'message' => 'forbidden' ), 403 );
		}
		check_ajax_referer( $action, '_ajax_nonce' );
	}

	/**
	 * Back to the mapping screen.
	 */
	private function back(): void {
		$this->back_to( Menu::categories_url() );
	}

	/**
	 * Redirects to a screen.
	 *
	 * @param string $url Address.
	 */
	private function back_to( string $url ): void {
		wp_safe_redirect( $url );
		exit;
	}
}