"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
/**
 * Calculate active page based on scroll top and row size properties.
 * This is useful of list with vertical-scrolled pagination.
 *
 * @param scrollTop
 * @param rowHeight
 * @param pageSize
 * @param options
 *
 * @returns The page number (start from 1)
 * @category pagination
 * @module calculatePageByScrollTop
 */
var calculatePageByScrollTop = function (
/** The current scroll top */
scrollTop, 
/** The height of each row */
rowHeight, 
/** The number of rows on each page */
pageSize, _a) {
    var _b = _a === void 0 ? {} : _a, _c = _b.startPage, startPage = _c === void 0 ? 1 : _c, _d = _b.pageBreakerHeight, pageBreakerHeight = _d === void 0 ? 0 : _d;
    // Get toppest-visible row index
    var topRowIndex = Math.ceil(scrollTop / rowHeight);
    // Get number of page breaker(s)
    var numPageBreaker = Math.floor(topRowIndex / pageSize);
    // Recalculate topRowIndex with page breaker
    var normTopRowIndex = Math.ceil((scrollTop - (numPageBreaker * pageBreakerHeight)) / rowHeight);
    // Calculate page by page size
    var calculatedPage = Math.ceil((normTopRowIndex + 1) / pageSize);
    // Calculate relative page
    var page = startPage - 1 + (calculatedPage < 1 ? 1 : calculatedPage);
    // Return page
    return page;
};
exports.default = calculatePageByScrollTop;