'use strict';

// INFORMATION
// ===========
// COPY THIS CODE INTO YOU BROWSER (chrome version >= 55)
//
// Description:
//      It will automatically change the client viewport
//      downwards. If the client viewport have reach the
//      the bottom the client viewport is moved to the
//      top of the page.
//
// Author:
//      thorgeir <thorgeir.sigurdsson@CYREN.com>
//
// CONSTANST
// =========
// CONTAINER:
//      A class name of an element that has its
//      Y coordinate at the bottom of the page.
// TIME_INTERVAL:
//      The interval measures the time during which
//      the client viewport is visible.
// DOWN:
//      The proportion of the client viewport height.
//      e.g. if DOWN equals 2 the viewport goes downwards
//      the half size of the client viewport height.

const CONTAINER='main-view'
const TIME_INTERVAL=8000//ms = 8 sec
const DOWN=2

// Expand all the views.
document.querySelectorAll('.dash-row-header-title')
    .forEach(function(element) { element.click(); });

//
// HELPER FUNCTIONS
//

// Positioning the viewport
// at the top of the page.
function topPage(){
    console.log( 'Go to top' )
    window.scrollTo(0, 0);
}

// Return the height of
// the clients viewport
function clientHeight(){
    return window.innerHeight;
}

// Moves the client viewport downwards
function down(){
    console.log( 'Scroll down by', clientHeight()/DOWN)
    window.scrollBy(0, clientHeight()/DOWN);
}

// Return True if the client
// viewport have reach the bottom
// of the page otherwise False.
function atBottom() {
    var main_view = document.getElementsByClassName(CONTAINER)
    var maxY = main_view[0].offsetHeight
    if ((clientHeight() + window.scrollY) >= maxY) {
        console.log( 'Reach the bottom', true )
        return true
    } else {
        console.log( 'Reach the bottom', false )
        return false
    }
}

// Copy from stackoverflow
// -> http://stackoverflow.com/questions/951021
function sleep(ms) {
      return new Promise(resolve => setTimeout(resolve, ms));
}

//
// THE LOGIC
//
// Ping Pong calls between these two functions.

// Waits for a given milliseconds
// and then starts the work.
async function wait( ms ) {
    console.log('Taking a break...');
    var counter = counter - 1;
    await sleep( ms );
    work();
}

// Move the client viewport down
// or too the top of the page and
// then wait for a while.
function work() {
    if( atBottom() ){
        topPage();
    } else{
        down();
    }
    wait( TIME_INTERVAL );
}

// Start the process
work()