<?php
/**
 * Admin
 *
 * @package PoweredCache
 */

namespace PoweredCache;

use const PoweredCache\Constants\POST_META_DISABLE_CACHE_KEY;
use function PoweredCache\Utils\clean_page_cache_dir;
use function PoweredCache\Utils\clean_site_cache_dir;
use function PoweredCache\Utils\delete_page_cache;
use function PoweredCache\Utils\get_post_related_urls;

if ( ! defined( 'ABSPATH' ) ) {
	exit; // Exit if accessed directly.
}

/**
 * Class Admin
 *
 * @package PoweredCache
 */
class AdvancedCache {

	/**
	 * Return an instance of the current class
	 *
	 * @return AdvancedCache
	 * @since 1.0
	 */
	public static function factory() {

		static $instance;

		if ( ! $instance ) {
			$instance = new self();
			$instance->setup();
		}

		return $instance;
	}

	/**
	 * Setup hooks
	 *
	 * @since 1.0
	 */
	public function setup() {
		$settings = \PoweredCache\Utils\get_settings();

		if ( ! $settings['enable_page_cache'] ) {
			return;
		}

		add_action( 'admin_bar_menu', array( $this, 'admin_bar_menu' ) );
		add_action( 'admin_post_powered_cache_purge_page_cache', array( $this, 'purge_page_cache' ) );
		add_action( 'admin_post_powered_cache_purge_page_cache_network', array( $this, 'purge_page_cache_network_wide' ) );
		add_action( 'pre_post_update', array( $this, 'purge_on_post_update' ), 10, 1 );
		add_action( 'save_post', array( $this, 'purge_on_post_update' ), 10, 1 );
		add_action( 'wp_trash_post', array( $this, 'purge_on_post_update' ), 10, 1 );
		add_action( 'switch_theme', array( $this, 'purge_on_switch_theme' ) );
		add_action( 'wp_set_comment_status', array( $this, 'purge_post_on_comment_status_change' ), 10, 2 );
		add_action( 'set_comment_cookies', array( $this, 'set_comment_cookie' ), 10, 2 );
		add_filter( 'powered_cache_post_related_urls', array( $this, 'powered_cache_post_related_urls' ) );
		add_filter( 'powered_cache_page_cache_enable', array( $this, 'maybe_caching_disabled' ) );
		add_filter( 'powered_cache_mod_rewrite', array( $this, 'maybe_disable_mod_rewrite' ), 99 );
	}

	/**
	 * Add purge button on admin bar
	 *
	 * @param object $wp_admin_bar Admin bar object
	 *
	 * @since 1.0
	 */
	public function admin_bar_menu( $wp_admin_bar ) {
		if ( POWERED_CACHE_IS_NETWORK && current_user_can( 'manage_network' ) ) {
			$wp_admin_bar->add_menu(
				array(
					'id'     => 'advanced-cache-purge-network',
					'title'  => __( 'Purge Page Cache [Network Wide - All Sites]', 'powered-cache' ),
					'href'   => wp_nonce_url( admin_url( 'admin-post.php?action=powered_cache_purge_page_cache_network' ), 'powered_cache_purge_page_cache_network' ),
					'parent' => 'powered-cache',
				)
			);
		}

		if ( current_user_can( 'manage_options' ) ) {
			$wp_admin_bar->add_menu(
				array(
					'id'     => 'advanced-cache-purge',
					'title'  => __( 'Purge Page Cache', 'powered-cache' ),
					'href'   => wp_nonce_url( admin_url( 'admin-post.php?action=powered_cache_purge_page_cache' ), 'powered_cache_purge_page_cache' ),
					'parent' => 'powered-cache',
				)
			);
		}
	}


	/**
	 * Purge page cache network wide
	 *
	 * @since 2.0
	 */
	public function purge_page_cache_network_wide() {
		if ( ! wp_verify_nonce( $_GET['_wpnonce'], 'powered_cache_purge_page_cache_network' ) ) {
			wp_nonce_ays( '' );
		}

		if ( current_user_can( 'manage_network' ) ) {
			clean_page_cache_dir();
			$redirect_url = add_query_arg( 'pc_action', 'flush_page_cache_network', wp_get_referer() );
		} else {
			$redirect_url = add_query_arg( 'pc_action', 'flush_page_cache_network_err_permission', wp_get_referer() );
		}

		wp_safe_redirect( esc_url_raw( $redirect_url ) );
		exit;
	}

	/**
	 * Purge page cache directory
	 *
	 * @since 1.0
	 * @since 1.1 clean site dir instead of root page caching dir
	 */
	public function purge_page_cache() {
		if ( ! wp_verify_nonce( $_GET['_wpnonce'], 'powered_cache_purge_page_cache' ) ) {
			wp_nonce_ays( '' );
		}

		if ( current_user_can( 'manage_options' ) ) {
			clean_site_cache_dir();
			$redirect_url = add_query_arg( 'pc_action', 'flush_page_cache', wp_get_referer() );
		} else {
			$redirect_url = add_query_arg( 'pc_action', 'flush_page_cache_err_permission', wp_get_referer() );
		}

		wp_safe_redirect( esc_url_raw( $redirect_url ) );
		exit;
	}


	/**
	 * Purge post related page cache
	 *
	 * @param int $post_id Post ID
	 *
	 * @since 1.0
	 */
	public function purge_on_post_update( $post_id ) {
		$current_post_status = get_post_status( $post_id );

		$urls = array();

		if ( in_array( $current_post_status, array( 'publish', 'trash' ), true ) ) {
			$urls = get_post_related_urls( $post_id );

			/**
			 * Page cache purge urls.
			 *
			 * @hook   powered_cache_advanced_cache_purge_urls
			 *
			 * @param  {array} $urls The list of URLs that will purged
			 * @param  {int} $post_id Post ID.
			 *
			 * @return {array} New value
			 * @since  1.0
			 */
			$urls = apply_filters( 'powered_cache_advanced_cache_purge_urls', $urls, $post_id );

			foreach ( $urls as $url ) {
				delete_page_cache( $url );
			}
		}

		/**
		 * Fires after purging cache on post update.
		 *
		 * @hook  powered_cache_advanced_cache_purge_post
		 *
		 * @param {int} $post_id The Post ID.
		 * @param {array} $urls The list of related urls with the updated post.
		 *
		 * @since 1.0
		 */
		do_action( 'powered_cache_advanced_cache_purge_post', $post_id, $urls );
	}

	/**
	 * Delete page cache when post update
	 *
	 * @param int    $comment_id     Comment ID
	 * @param string $comment_status Status of the comment
	 *
	 * @since 1.0
	 */
	public function purge_post_on_comment_status_change( $comment_id, $comment_status ) {
		$comment  = get_comment( $comment_id );
		$post_id  = $comment->comment_post_ID;
		$post_url = get_permalink( $post_id );
		delete_page_cache( $post_url );

		/**
		 * Fires after purging cache for a post that associated a comment
		 *
		 * @param {int} $post_id Post ID.
		 * @param {string} $post_url Post permalink.
		 * @param {int} $comment_id Comment ID.
		 *
		 * @since 2.0
		 */
		do_action( 'powered_cache_advanced_cache_purge_on_comment_status_change', $post_id, $post_url, $comment_id );
	}

	/**
	 * Purge site when switching to a new theme
	 *
	 * @since 2.0
	 */
	public function purge_on_switch_theme() {
		clean_site_cache_dir();
	}

	/**
	 * Leave a cookie when commenting on a post as usual and don't show the cached page.
	 * `comment_author_*` cookies are site-wide available.
	 * Don't show cached results just for left a comment 5 months ago is not seems efficient here.
	 *
	 * @param object $comment Comment object
	 * @param object $user    User Object
	 *
	 * @since 1.0
	 */
	public function set_comment_cookie( $comment, $user ) {
		$post_id = $comment->comment_post_ID;
		$path    = wp_parse_url( get_permalink( $post_id ), PHP_URL_PATH );
		setcookie( 'powered_cache_commented_posts[' . $post_id . ']', $path, ( time() + DAY_IN_SECONDS * 30 ), $path );
	}


	/**
	 * Adds custom pages to post related urls
	 *
	 * @param array $urls The list of the urls
	 *
	 * @return array urls
	 * @since 1.1
	 */
	public function powered_cache_post_related_urls( $urls ) {
		$settings = \PoweredCache\Utils\get_settings();

		$additional_pages = $settings['purge_additional_pages'];

		if ( empty( $additional_pages ) ) {
			return $urls;
		}

		// we only need relative path
		$additional_pages      = str_replace( site_url(), '', $additional_pages );
		$additional_page_paths = explode( PHP_EOL, $additional_pages );
		$additional_urls       = array();

		foreach ( $additional_page_paths as $page ) {
			$additional_urls[] = site_url( $page );
		}

		$urls = array_merge( $urls, $additional_urls );

		return $urls;
	}


	/**
	 * Get the list of rejected cookies
	 *
	 * @return mixed|void
	 * @since 2.0
	 */
	public static function get_rejected_cookies() {
		$settings = \PoweredCache\Utils\get_settings();
		$cookies  = [];

		if ( ! empty( $settings['rejected_cookies'] ) ) {
			$cookies = preg_split( '#(\r\n|\r|\n)#', $settings['rejected_cookies'], - 1, PREG_SPLIT_NO_EMPTY );
		}

		$wp_cookies = [ 'wp-postpass', 'wordpressuser_', 'wordpresspass_', 'wordpress_sec_', 'wordpress_logged_in_', 'powered_cache_commented_posts' ];

		if ( ! empty( $cookies ) ) {
			$wp_cookies = array_merge( $cookies, $wp_cookies );
		}

		/**
		 * Filter rejected cookie list.
		 *
		 * @hook   powered_cache_rejected_cookies
		 *
		 * @param  {array} $wp_cookies The rejected cookie list from the caching.
		 *
		 * @return {array} Rejected cookie list
		 * @since  2.0
		 */
		return apply_filters( 'powered_cache_rejected_cookies', $wp_cookies );
	}

	/**
	 * Get the list of rejected cookies
	 *
	 * @return mixed|void
	 * @since 2.0
	 */
	public static function get_vary_cookies() {
		$settings = \PoweredCache\Utils\get_settings();
		$cookies  = [];

		if ( ! empty( $settings['vary_cookies'] ) ) {
			$cookies = preg_split( '#(\r\n|\r|\n)#', $settings['vary_cookies'], - 1, PREG_SPLIT_NO_EMPTY );
		}

		/**
		 * Filter vary cookie list.
		 *
		 * @hook   powered_cache_vary_cookies
		 *
		 * @param  {array} $cookies The varied cookie list, which allows to create separate cache based on the match.
		 *
		 * @return {array} Vary cookie list
		 * @since  2.0
		 */
		return apply_filters( 'powered_cache_vary_cookies', $cookies );
	}


	/**
	 * Get the list of rejected user agents
	 *
	 * @return mixed|void
	 * @since 2.0
	 */
	public static function get_rejected_user_agents() {
		$settings             = \PoweredCache\Utils\get_settings();
		$rejected_user_agents = [];

		if ( ! empty( $settings['rejected_user_agents'] ) ) {
			$rejected_user_agents = preg_split( '#(\r\n|\r|\n)#', $settings['rejected_user_agents'], - 1, PREG_SPLIT_NO_EMPTY );
		}

		$rejected_user_agents[] = 'facebookexternalhit';

		/**
		 * Filter rejected user agent list.
		 *
		 * @hook   powered_cache_rejected_user_agents
		 *
		 * @param  {array} $rejected_user_agents The user agents that will not see the cached page.
		 *
		 * @return {array} Rejected user agent list.
		 * @since  2.0
		 */
		return apply_filters( 'powered_cache_rejected_user_agents', $rejected_user_agents );
	}

	/**
	 * Get the list of rejected uri that nerver get cached
	 *
	 * @return mixed|void
	 * @since 2.0
	 */
	public static function get_rejected_uri() {
		$settings          = \PoweredCache\Utils\get_settings();
		$rejected_uri_list = [];

		if ( ! empty( $settings['rejected_uri'] ) ) {
			$rejected_uri_list = preg_split( '#(\r\n|\r|\n)#', $settings['rejected_uri'], - 1, PREG_SPLIT_NO_EMPTY );
		}

		/**
		 * Filter rejected uri list
		 *
		 * @hook   powered_cache_rejected_uri_list
		 *
		 * @param  {array} $rejected_uri_list The list of rejected uri that nerver get cached.
		 *
		 * @return {array} New value
		 * @since  2.0
		 */
		return apply_filters( 'powered_cache_rejected_uri_list', $rejected_uri_list );
	}


	/**
	 * These query strings will be ignored during the caching
	 *
	 * @return mixed|void
	 */
	public static function get_accepted_query_strings() {
		$settings               = \PoweredCache\Utils\get_settings();
		$accepted_query_strings = [];

		if ( ! empty( $settings['accepted_query_strings'] ) ) {
			$accepted_query_strings = preg_split( '#(\r\n|\r|\n)#', $settings['accepted_query_strings'], - 1, PREG_SPLIT_NO_EMPTY );
		}

		$query_strings = [
			'fbclid',
			'fb_action_ids',
			'fb_action_types',
			'ref',
			'gclid',
			'fb_source',
			'utm_source',
			'utm_medium',
			'utm_campaign',
			'utm_term',
			'utm_content',
			'utm_expid',
			'_ga',
			'mc_cid',
			'mc_eid',
			'campaignid',
			'adgroupid',
			'adid',
			'age-verified',
			'usqp',
			'cn-reloaded',
			'ao_noptimize',
			'lang',
		];

		if ( ! empty( $accepted_query_strings ) ) {
			$query_strings = array_merge( $query_strings, $accepted_query_strings );
		}

		/**
		 * Filter accepted query strings.
		 *
		 * @hook   powered_cache_accepted_query_strings
		 *
		 * @param  {array} $query_strings The list of query strings will be ignored during the caching
		 *
		 * @return {array} New value
		 * @since  2.0
		 */
		return apply_filters( 'powered_cache_accepted_query_strings', $query_strings );
	}


	/**
	 * Disable caching of the individual page when it marked as dont' cache
	 *
	 * @param bool $status Cache status
	 *
	 * @return bool
	 */
	public function maybe_caching_disabled( $status ) {
		if ( is_single() ) {
			$is_cache_disabled = (bool) get_post_meta( get_the_ID(), POST_META_DISABLE_CACHE_KEY, true );
			if ( $is_cache_disabled ) {
				return false;
			}
		}

		return $status;
	}

	/**
	 * Maybe disable rewrite rules based on the settings
	 *
	 * @param bool $rewrite_status mod rewrite status
	 *
	 * @return bool
	 * @since 2.0
	 */
	public function maybe_disable_mod_rewrite( $rewrite_status ) {
		$vary_cookies = self::get_vary_cookies();
		if ( ! empty( $vary_cookies ) ) {
			$rewrite_status = false;
		}

		return $rewrite_status;
	}

}