WP Turbo Duplicate

					<?php
/**
 * Plugin Name: Duplicate Page or Post
 * Plugin URI: https://example.com/duplicate-page-post/
 * Description: Allows users to easily duplicate a page or post in WordPress.
 * Version: 1.0.0
 * Author: WP Turbo
 * Author URI: https://wpturbo.dev
 * License: GPLv2 or later
 * Text Domain: wpturbo
 */

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

/**
 * Register the duplicate page/post functionality.
 */
function wpturbo_duplicate_page_post() {
    add_action( 'post_row_actions', 'wpturbo_add_duplicate_link', 10, 2 );
    add_action( 'admin_action_wpturbo_duplicate_page', 'wpturbo_duplicate_page' );
    add_action( 'admin_action_wpturbo_duplicate_post', 'wpturbo_duplicate_post' );
}

/**
 * Add duplicate link to the post row actions.
 *
 * @param array   $actions The post row actions.
 * @param WP_Post $post    The current post object.
 *
 * @return array The modified post row actions.
 */
function wpturbo_add_duplicate_link( $actions, $post ) {
    if ( 'page' === $post->post_type ) {
        $duplicate_url = wp_nonce_url( admin_url( 'admin.php?action=wpturbo_duplicate_page&amp;post=' . $post->ID ), 'wpturbo_duplicate_nonce' );
        $actions['duplicate'] = '<a href="' . $duplicate_url . '" title="' . esc_attr__( 'Duplicate this page', 'wpturbo' ) . '">' . esc_html__( 'Duplicate', 'wpturbo' ) . '</a>';
    } elseif ( 'post' === $post->post_type ) {
        $duplicate_url = wp_nonce_url( admin_url( 'admin.php?action=wpturbo_duplicate_post&amp;post=' . $post->ID ), 'wpturbo_duplicate_nonce' );
        $actions['duplicate'] = '<a href="' . $duplicate_url . '" title="' . esc_attr__( 'Duplicate this post', 'wpturbo' ) . '">' . esc_html__( 'Duplicate', 'wpturbo' ) . '</a>';
    }

    return $actions;
}

/**
 * Duplicate a page.
 */
function wpturbo_duplicate_page() {
    if ( ! isset( $_GET['post'] ) || ! isset( $_GET['action'] ) || 'wpturbo_duplicate_page' !== $_GET['action'] ) {
        return;
    }

    $post_id = absint( $_GET['post'] );

    if ( ! current_user_can( 'edit_pages' ) || ! wpturbo_verify_nonce() ) {
        wp_die( esc_html__( 'You do not have permission to duplicate this page.', 'wpturbo' ) );
    }

    $new_page_id = wpturbo_duplicate_content( $post_id );

    wp_redirect( admin_url( 'post.php?action=edit&amp;post=' . $new_page_id ) );
    exit;
}

/**
 * Duplicate a post.
 */
function wpturbo_duplicate_post() {
    if ( ! isset( $_GET['post'] ) || ! isset( $_GET['action'] ) || 'wpturbo_duplicate_post' !== $_GET['action'] ) {
        return;
    }

    $post_id = absint( $_GET['post'] );

    if ( ! current_user_can( 'edit_posts' ) || ! wpturbo_verify_nonce() ) {
        wp_die( esc_html__( 'You do not have permission to duplicate this post.', 'wpturbo' ) );
    }

    $new_post_id = wpturbo_duplicate_content( $post_id );

    wp_redirect( admin_url( 'post.php?action=edit&amp;post=' . $new_post_id ) );
    exit;
}

/**
 * Duplicate the content of a page or post.
 *
 * @param int $post_id The ID of the page or post to duplicate.
 *
 * @return int The ID of the duplicated page or post.
 */
function wpturbo_duplicate_content( $post_id ) {
    $post = get_post( $post_id );

    if ( is_null( $post ) ) {
        return 0;
    }

    $new_post_id = wp_insert_post(
        array(
            'post_title'   => $post->post_title . ' (Duplicate)',
            'post_content' => $post->post_content,
            'post_status'  => 'draft',
            'post_type'    => $post->post_type,
        )
    );

    if ( $new_post_id ) {
        // Duplicate post meta.
        $post_meta = get_post_meta( $post_id );
        foreach ( $post_meta as $meta_key => $meta_values ) {
            foreach ( $meta_values as $meta_value ) {
                add_post_meta( $new_post_id, $meta_key, $meta_value );
            }
        }

        // Duplicate taxonomies.
        $taxonomies = get_object_taxonomies( $post->post_type );
        foreach ( $taxonomies as $taxonomy ) {
            $terms = wp_get_post_terms( $post_id, $taxonomy, array( 'fields' => 'slugs' ) );
            wp_set_post_terms( $new_post_id, $terms, $taxonomy, false );
        }

        // Duplicate featured image.
        $thumbnail_id = get_post_thumbnail_id( $post_id );
        if ( $thumbnail_id ) {
            $thumbnail = get_attached_file( $thumbnail_id );
            $thumbnail_data = wp_read_image_metadata( $thumbnail );
            $thumbnail_new = wpturbo_duplicate_featured_image( $thumbnail, $thumbnail_data, $new_post_id );
            if ( $thumbnail_new ) {
                set_post_thumbnail( $new_post_id, $thumbnail_new );
            }
        }
    }

    return $new_post_id;
}

/**
 * Duplicate the featured image of a page or post.
 *
 * @param string $thumbnail The path to the original featured image file.
 * @param array  $metadata  The metadata of the original featured image.
 * @param int    $post_id   The ID of the duplicated page or post.
 *
 * @return int The ID of the duplicated featured image.
 */
function wpturbo_duplicate_featured_image( $thumbnail, $metadata, $post_id ) {
    $filetype = wp_check_filetype( $thumbnail );
    $new_thumbnail = wp_upload_bits( $post_id . '-' . basename( $thumbnail ), null, file_get_contents( $thumbnail ) );

    if ( $new_thumbnail['error'] ) {
        return 0;
    }

    $attachment = array(
        'post_mime_type' => $filetype['type'],
        'post_title'     => $metadata['title'],
        'post_content'   => '',
        'post_status'    => 'inherit',
    );

    $attachment_id = wp_insert_attachment( $attachment, $new_thumbnail['file'], $post_id );
    if ( ! is_wp_error( $attachment_id ) ) {
        wp_update_attachment_metadata( $attachment_id, wp_generate_attachment_metadata( $attachment_id, $new_thumbnail['file'] ) );
        return $attachment_id;
    }

    return 0;
}

/**
 * Verify the duplicate nonce.
 *
 * @return bool Whether the nonce is valid or not.
 */
function wpturbo_verify_nonce() {
    $nonce = isset( $_GET['_wpnonce'] ) ? $_GET['_wpnonce'] : '';
    return wp_verify_nonce( $nonce, 'wpturbo_duplicate_nonce' );
}

// Register the duplicate page/post functionality.
wpturbo_duplicate_page_post();