/* jshint esversion: 6 */

(function( v, undefined ) {
    'use strict';

    // scroll to top button
    {
        var st_buttons = document.querySelectorAll( '.vamtam-scroll-to-top' );

        if ( st_buttons.length ) {
            var side_st_button = document.getElementById( 'scroll-to-top' ),
                pageMiddle = window.innerHeight / 2;

            if ( side_st_button ) {
                v.addScrollHandler( {
                    init: function() {},
                    measure: function() {
                        pageMiddle = window.innerHeight / 2;
                    },
                    mutate: function( cpos ) {
                        if ( cpos > pageMiddle ) {
                            side_st_button.style.opacity   = 1;
                            side_st_button.style.transform = 'translate3d(0, 0, 0)';
                        } else {
                            side_st_button.style.opacity   = '';
                            side_st_button.style.transform = 'translate3d(0, 100%, 0)';
                        }
                    }
                } );
            }

            document.addEventListener( 'click', ( e ) => {
                if ( e.target.closest( '.vamtam-scroll-to-top' ) ) {
                    e.preventDefault();

                    // iOS Safari uses a simple animation, normal browsers use scroll-behavior:smooth
                    if ( /iPad|iPhone|iPod/.test( navigator.userAgent ) && ! window.MSStream ) {
                        window.scrollTo( 0, 0 );
                    } else {
                        window.scroll( { left: 0, top: 0, behavior: 'smooth' } );
                    }
                }
            }, true );
        }

        ( function wpRocketLazyRenderSafeGuard() {
            window.addEventListener( 'load', function() {
                document.querySelectorAll('[data-wpr-lazyrender]').forEach(el => delete el.dataset.wprLazyrender);
            } );
        } )();
    }
})( window.VAMTAM );
