Generate x number of pages to display out of the total number of pages and current page number.

pagination_helper.js

/**
 * Generate x number of pages to display out of the total number of pages and 
 * current page number.
 *
 * @param {Integer} totalPagesNumber: Total number of pages.
 * @param {Integer} displayPagesNumber: Number of pages to display.
 * @param {Integer} currentPageNumber: Current page number.
 * @return {Array}:
 */
function getPagesRange(totalPagesNumber, displayPagesNumber, currentPageNumber) {
    var lowerLimit = upperLimit = Math.min(currentPageNumber, totalPagesNumber);

    for (var i = 1; i < displayPagesNumber && i < totalPagesNumber;) {
        if (lowerLimit > 1 ) { lowerLimit--; i++; }
        if (i < displayPagesNumber && upperLimit < totalPagesNumber) { upperLimit++; i++; }
    }

    var range = [];    
    for (var i = lowerLimit; i <= upperLimit; i++) {
        range.push(i);
    }
 
    return range;
}