Docs_List_Table.php

<?php

namespace WeDevs\WeDocs\Admin;

/**
 * Modifier functions in docs list table.
 */
class Docs_List_Table {

    /**
     * Constructor
     */
    public function __construct() {
        add_filter('manage_docs_posts_columns', [$this, 'docs_list_columns']);
        add_action('manage_docs_posts_custom_column', [$this, 'docs_list_columns_row'], 10, 2);
        add_filter('manage_edit-docs_sortable_columns', [$this, 'docs_sortable_columns']);

        add_action('load-edit.php', [$this, 'edit_docs_load']);
        add_action('load-post.php', [$this, 'add_meta_box']);

        // load css
        add_action('admin_print_styles-post.php', [$this, 'helpfulness_css']);
        add_action('admin_print_styles-edit.php', [$this, 'helpfulness_css']);
    }

    public function add_meta_box() {
        add_meta_box('op-menu-meta-box-id', __('Helpfulness', 'wedocs'), [$this, 'helpfulness_metabox'], 'docs', 'side', 'core');
    }

    public function helpfulness_css() {
        if ('docs' != get_current_screen()->post_type) {
            return;
        } ?>
        <style type="text/css">
            .wedocs-positive {
                color: green;
            }

            .wedocs-negative {
                color: red;
                text-align: right;
            }
        </style>
    <?php
    }

    public function helpfulness_metabox() {
        global $post;

        $positive = (int) get_post_meta($post->ID, 'positive', true);
        $negative = (int) get_post_meta($post->ID, 'negative', true);
    ?>
        <table style="width: 100%;">
            <tr>
                <td class="wedocs-positive">
                    <span class="dashicons dashicons-thumbs-up"></span>
                    <?php printf('%d', $positive); ?>
                </td>

                <td class="wedocs-negative">
                    <span class="dashicons dashicons-thumbs-down"></span>
                    <?php printf('%d', $negative); ?>
                </td>
            </tr>
        </table>
<?php
    }

    /**
     * Vote column in the class UI.
     *
     * @param array $column
     *
     * @return array
     */
    public function docs_list_columns($columns) {
        $vote = ['votes' => __('Votes', 'wedocs')];

        // insert before last element, date
        $first_items = array_splice($columns, 0, 3); // remove first 3 items and store to $first_items, date remains to $columns
        $new_columns = array_merge($first_items, $vote, $columns); // merge all those

        return $new_columns;
    }

    public function docs_sortable_columns($columns) {
        $columns['votes'] = ['votes', true];

        return $columns;
    }

    public function docs_list_columns_row($column_name, $post_id) {
        if ('votes' == $column_name) {
            $positive = get_post_meta($post_id, 'positive', true);
            $negative = get_post_meta($post_id, 'negative', true);

            printf('<span class="wedocs-positive">%d</span>/<span class="wedocs-negative">%d</span>', $positive, $negative);
        }
    }

    public function edit_docs_load() {
        add_filter('request', [$this, 'sort_docs']);
    }

    // Sorts the movies.
    public function sort_docs($vars) {
        // Check if we're viewing the 'movie' post type.
        if (isset($vars['post_type']) && 'docs' == $vars['post_type']) {
            // Check if 'orderby' is set to 'duration'.
            if (isset($vars['orderby']) && 'votes' == $vars['orderby']) {
                $vars = array_merge(
                    $vars,
                    [
                        'meta_key' => 'positive',
                        'orderby'  => 'meta_value_num',
                    ]
                );
            }
        }

        return $vars;
    }
}