<?php 
/**
* Kalon Metabox.
*
* @package Kalon
*
*/ 
function kalon_add_sidebar_layout_box(){
    add_meta_box( 
        'kalon_sidebar_layout',
        __( 'Sidebar Layout', 'kalon' ),
        'kalon_sidebar_layout_callback', 
        'page',
        'normal',
        'high'
    );
}
add_action( 'add_meta_boxes', 'kalon_add_sidebar_layout_box' );

/**
 * Get Sidebar Layout Data
 *
 * @return array
 */
if( ! function_exists( 'kalon_get_sidebar_layout_data' ) ){
    function kalon_get_sidebar_layout_data(){ 
            return array(
            'right-sidebar' => array(
                'value'=> 'right-sidebar',
                'label'=> __( 'Right Sidebar (default)', 'kalon'),
                'thumbnail'=> get_template_directory_uri() . '/images/right-sidebar.png'         
            ),
            'no-sidebar' => array(
                'value' => 'no-sidebar',
                'label' => __('No Sidebar','kalon'),
                'thumbnail'=> get_template_directory_uri() . '/images/no-sidebar.png'
            )       
        );
    }
}

function kalon_sidebar_layout_callback(){
    global $post;
    $kalon_sidebar_layout = kalon_get_sidebar_layout_data();
    wp_nonce_field( basename( __FILE__ ), 'kalon_nonce' );
?>
 
<table class="form-table">
    <tr>
        <td colspan="4"><em class="f13"><?php esc_html_e( 'Choose Sidebar Template', 'kalon' ); ?></em></td>
    </tr>
    <tr>
        <td>
        <?php  
            foreach( $kalon_sidebar_layout as $field ){  
                $layout = get_post_meta( $post->ID, 'kalon_sidebar_layout', true ); ?>

            <div class="radio-image-wrapper" style="float:left; margin-right:30px;">
                <label class="description">
                    <span><img src="<?php echo esc_url( $field['thumbnail'] ); ?>" alt="<?php echo esc_attr( $field['label'] ); ?>" /></span><br/>
                    <input type="radio" name="kalon_sidebar_layout" value="<?php echo esc_attr( $field['value'] ); ?>" <?php checked( $field['value'], $layout ); if( empty( $layout ) ){ checked( $field['value'], 'right-sidebar' ); }?>/>&nbsp;<?php echo esc_html( $field['label'] ); ?>
                </label>
            </div>
            <?php } // end foreach 
            ?>
            <div class="clear"></div>
        </td>
    </tr>
</table>
 
<?php }

function kalon_save_sidebar_layout( $post_id ){
    $kalon_sidebar_layout = kalon_get_sidebar_layout_data();

    // Verify the nonce before proceeding.
    if( ! isset( $_POST[ 'kalon_nonce' ] ) || ! wp_verify_nonce( $_POST[ 'kalon_nonce' ], basename( __FILE__ ) ) )
        return;
    
    // Stop WP from clearing custom fields on autosave
    if( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )  
        return;

    if( 'page' == $_POST['post_type'] ){  
        if( ! current_user_can( 'edit_page', $post_id ) ) return $post_id;  
    }elseif( ! current_user_can( 'edit_post', $post_id ) ){  
        return $post_id;  
    }

    $layout = isset( $_POST['kalon_sidebar_layout'] ) ? sanitize_key( $_POST['kalon_sidebar_layout'] ) : 'right-sidebar';

    if( array_key_exists( $layout, $kalon_sidebar_layout ) ){
        update_post_meta( $post_id, 'kalon_sidebar_layout', $layout );
    }else{
        delete_post_meta( $post_id, 'kalon_sidebar_layout' );
    }    
}
add_action('save_post', 'kalon_save_sidebar_layout');