<?php
/* WP Admin Dashboard > Export Metros DB */
add_action( 'admin_menu', 'metros_export_db' );

function metros_export_db(){
    add_menu_page(
        'Export Metros CSV',
        'Metros CSV',
        'manage_options',
        'metros-csv',
        'metros_csv_export',
        'dashicons-external'
    );
}

function metros_csv_export() {
    global $title;
    ?>

    <div class="wrap">
        <h1><?php echo $title; ?></h1>
        <h2>Easily export all the Metros with ID's from Database.</h2>
        <p class="description">The outcome will be: Metro ID, Metro Name, Metro URL.</p>

        <?php
        if(isset($_POST['submit'])) {

            $terms = get_terms(
                array(
                    'taxonomy'   => 'metro',
                    'hide_empty' => false,
                )
            );

            $path = wp_upload_dir();
            $date = date("d-m-Y");

            $outstream = fopen($path['path']."/metros" . $date . ".csv", "w");

            // Set first fields
            $fields = array('Metro ID', 'Metro Name', 'Metro URL');

            fputcsv($outstream, $fields);

            if ( ! empty( $terms ) && is_array( $terms ) ) {

                foreach ( $terms as $term ) {

                    fputcsv($outstream, array($term->term_id,html_entity_decode($term->name),get_term_link( $term ) ));

                }

            }

            fclose($outstream);

            echo '<br><a href="'.$path['url'].'/metros' . $date . '.csv" style="font-size:16px;color:green;font-weight:bold;">Export is Done! Download here</a>';

        }
        ?>

        <form action="" method="post">
            <table class="form-table">
                <tbody>
                <tr class="row">
                    <td style="padding:15px 0;">
                        <input type="submit" name="submit" id="submit" class="button button-primary" value="Export Metros CSV">
                    </td>
                </tr>
                </tbody>
            </table>
        </form>
    </div>

<?php }