<?php
/**
 * WordPress Optimizer class.
 *
 * @package SpeedNest
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

/**
 * Class WPSCO_WordPress_Optimizer
 *
 * Handles WordPress-specific optimizations: emojis, embeds, XML-RPC,
 * version removal, heartbeat control, feeds, and discovery links.
 */
class WPSCO_WordPress_Optimizer {

    /**
     * Constructor.
     */
    public function __construct() {
        $settings = wpsco_get_setting();

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

        // Disable emojis.
        if ( ! empty( $settings['disable_emojis'] ) ) {
            $this->disable_emojis();
        }

        // Disable embeds.
        if ( ! empty( $settings['disable_embeds'] ) ) {
            $this->disable_embeds();
        }

        // Disable XML-RPC.
        if ( ! empty( $settings['disable_xmlrpc'] ) ) {
            add_filter( 'xmlrpc_enabled', '__return_false' );
            add_filter( 'wp_headers', array( $this, 'remove_xmlrpc_header' ) );
        }

        // Remove WordPress version.
        if ( ! empty( $settings['remove_wp_version'] ) ) {
            remove_action( 'wp_head', 'wp_generator' );
            add_filter( 'the_generator', '__return_empty_string' );
        }

        // Remove generator meta.
        if ( ! empty( $settings['remove_generator_meta'] ) ) {
            remove_action( 'wp_head', 'wp_generator' );
            add_filter( 'the_generator', '__return_empty_string' );
        }

        // Disable feeds.
        if ( ! empty( $settings['disable_feeds'] ) ) {
            remove_action( 'wp_head', 'feed_links', 2 );
            remove_action( 'wp_head', 'feed_links_extra', 3 );
        }

        // Disable pingbacks.
        if ( ! empty( $settings['disable_pingbacks'] ) ) {
            add_filter( 'xmlrpc_methods', array( $this, 'disable_pingback_methods' ) );
            add_filter( 'pings_open', '__return_false', 9999 );
        }

        // Remove shortlinks.
        if ( ! empty( $settings['remove_shortlinks'] ) ) {
            remove_action( 'wp_head', 'wp_shortlink_wp_head' );
            remove_action( 'template_redirect', 'wp_shortlink_header', 11 );
        }

        // Remove discovery links.
        if ( ! empty( $settings['remove_discovery_links'] ) ) {
            remove_action( 'wp_head', 'rsd_link' );
            remove_action( 'wp_head', 'wlwmanifest_link' );
            remove_action( 'wp_head', 'rest_output_link_wp_head', 10 );
            remove_action( 'wp_head', 'wp_oembed_add_discovery_links', 10 );
        }

        // Heartbeat control.
        $this->control_heartbeat( $settings );

        // Htaccess management for Apache/LiteSpeed.
        if ( is_admin() ) {
            add_action( 'admin_init', array( $this, 'maybe_update_htaccess' ) );
        }
    }

    /**
     * Update .htaccess if server is Apache and setting changed.
     */
    public function maybe_update_htaccess() {
        $settings = wpsco_get_setting();
        if ( ! empty( $settings['emergency_disable'] ) ) {
            $this->remove_htaccess_rules();
            return;
        }

        if ( ! empty( $settings['browser_cache_htaccess'] ) || ! empty( $settings['compression_htaccess'] ) ) {
            $this->write_htaccess_rules( ! empty( $settings['compression_htaccess'] ) );
        } else {
            $this->remove_htaccess_rules();
        }
    }

    /**
     * Write rules inside # BEGIN WP_SPEED_OPTIMIZER markers.
     *
     * @param bool $enable_compression Whether to add compression rules.
     */
    public function write_htaccess_rules( $enable_compression = true ) {
        $server_type = wpsco_get_server_type();
        if ( ! in_array( $server_type, array( 'apache', 'litespeed', 'openlitespeed' ), true ) ) {
            return;
        }

        if ( ! function_exists( 'get_home_path' ) ) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if ( ! function_exists( 'insert_with_markers' ) ) {
            require_once ABSPATH . 'wp-admin/includes/misc.php';
        }

        $htaccess_file = get_home_path() . '.htaccess';
        if ( ! file_exists( $htaccess_file ) || ! wp_is_writable( $htaccess_file ) ) {
            return;
        }

        $rules   = array();
        $rules[] = '<IfModule mod_expires.c>';
        $rules[] = 'ExpiresActive On';
        $rules[] = 'ExpiresByType image/jpg "access plus 1 year"';
        $rules[] = 'ExpiresByType image/jpeg "access plus 1 year"';
        $rules[] = 'ExpiresByType image/gif "access plus 1 year"';
        $rules[] = 'ExpiresByType image/png "access plus 1 year"';
        $rules[] = 'ExpiresByType image/webp "access plus 1 year"';
        $rules[] = 'ExpiresByType image/avif "access plus 1 year"';
        $rules[] = 'ExpiresByType image/svg+xml "access plus 1 year"';
        $rules[] = 'ExpiresByType text/css "access plus 1 month"';
        $rules[] = 'ExpiresByType application/javascript "access plus 1 month"';
        $rules[] = 'ExpiresByType font/woff2 "access plus 1 year"';
        $rules[] = '</IfModule>';

        if ( $enable_compression ) {
            $rules[] = '<IfModule mod_deflate.c>';
            $rules[] = 'AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css application/javascript application/json';
            $rules[] = '</IfModule>';
        }

        insert_with_markers( $htaccess_file, 'SpeedNest', $rules );
    }

    /**
     * Remove rules marked with # BEGIN SpeedNest.
     */
    public function remove_htaccess_rules() {
        if ( ! function_exists( 'get_home_path' ) ) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if ( ! function_exists( 'insert_with_markers' ) ) {
            require_once ABSPATH . 'wp-admin/includes/misc.php';
        }

        $htaccess_file = get_home_path() . '.htaccess';
        if ( ! file_exists( $htaccess_file ) || ! wp_is_writable( $htaccess_file ) ) {
            return;
        }

        insert_with_markers( $htaccess_file, 'SpeedNest', array() );
        insert_with_markers( $htaccess_file, 'WP_SPEED_OPTIMIZER', array() );
    }

    /**
     * Disable WordPress emojis.
     */
    private function disable_emojis() {
        remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
        remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
        remove_action( 'wp_print_styles', 'print_emoji_styles' );
        remove_action( 'admin_print_styles', 'print_emoji_styles' );
        remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
        remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
        remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );

        add_filter( 'tiny_mce_plugins', function ( $plugins ) {
            return is_array( $plugins ) ? array_diff( $plugins, array( 'wpemoji' ) ) : $plugins;
        } );

        add_filter( 'wp_resource_hints', function ( $urls, $relation_type ) {
            if ( 'dns-prefetch' === $relation_type ) {
                $urls = array_filter( $urls, function ( $url ) {
                    return strpos( $url, 'emoji' ) === false;
                } );
            }
            return $urls;
        }, 10, 2 );
    }

    /**
     * Disable WordPress embeds.
     */
    private function disable_embeds() {
        remove_action( 'wp_head', 'wp_oembed_add_host_js' );
        remove_action( 'wp_head', 'wp_oembed_add_discovery_links' );
        remove_action( 'rest_api_init', 'wp_oembed_register_route' );

        add_filter( 'embed_oembed_discover', '__return_false' );

        remove_filter( 'oembed_dataparse', 'wp_filter_oembed_result', 10 );
        remove_filter( 'oembed_response_data', 'get_oembed_response_data_rich', 10 );

        wp_deregister_script( 'wp-embed' );
    }

    /**
     * Remove X-Pingback header.
     *
     * @param array $headers HTTP headers.
     * @return array
     */
    public function remove_xmlrpc_header( $headers ) {
        unset( $headers['X-Pingback'] );
        return $headers;
    }

    /**
     * Disable pingback XML-RPC methods.
     *
     * @param array $methods XML-RPC methods.
     * @return array
     */
    public function disable_pingback_methods( $methods ) {
        unset( $methods['pingback.ping'] );
        unset( $methods['pingback.extensions.getPingbacks'] );
        return $methods;
    }

    /**
     * Control Heartbeat API.
     *
     * @param array $settings Plugin settings.
     */
    private function control_heartbeat( $settings ) {
        $frontend = isset( $settings['heartbeat_frontend'] ) ? $settings['heartbeat_frontend'] : 'default';
        $admin    = isset( $settings['heartbeat_admin'] ) ? $settings['heartbeat_admin'] : 'default';
        $editor   = isset( $settings['heartbeat_editor'] ) ? $settings['heartbeat_editor'] : 'default';

        // Frontend.
        if ( 'disable' === $frontend && ! is_admin() ) {
            wp_deregister_script( 'heartbeat' );
        } elseif ( 'default' !== $frontend && ! is_admin() ) {
            add_filter( 'heartbeat_settings', function ( $heartbeat_settings ) use ( $frontend ) {
                $heartbeat_settings['interval'] = (int) $frontend;
                return $heartbeat_settings;
            } );
        }

        // Admin (but not editor).
        if ( is_admin() ) {
            $screen = function_exists( 'get_current_screen' ) ? get_current_screen() : null;
            $is_editor = $screen && ( 'post' === $screen->base || 'post-new' === $screen->base );

            if ( $is_editor && 'default' !== $editor ) {
                if ( 'disable' === $editor ) {
                    // Do not disable in editor — may cause issues.
                    // Instead, set to maximum interval.
                    add_filter( 'heartbeat_settings', function ( $heartbeat_settings ) {
                        $heartbeat_settings['interval'] = 120;
                        return $heartbeat_settings;
                    } );
                } else {
                    add_filter( 'heartbeat_settings', function ( $heartbeat_settings ) use ( $editor ) {
                        $heartbeat_settings['interval'] = (int) $editor;
                        return $heartbeat_settings;
                    } );
                }
            } elseif ( ! $is_editor && 'default' !== $admin ) {
                if ( 'disable' === $admin ) {
                    wp_deregister_script( 'heartbeat' );
                } else {
                    add_filter( 'heartbeat_settings', function ( $heartbeat_settings ) use ( $admin ) {
                        $heartbeat_settings['interval'] = (int) $admin;
                        return $heartbeat_settings;
                    } );
                }
            }
        }
    }
}