etnbrd/flx-compiler

/**
 *
 * @param {Object} obj
 * @param {Array<String>} accessorStrings
 * @returns {*}
 */
var getValueForProp = function (obj, accessorStrings) {
    var prop = obj;
    while(accessorStrings.length) {
        prop = prop[accessorStrings[0]];
        accessorStrings = accessorStrings.slice(1);
    }
    return prop;
};

/**
 *
 * @param {Object} element
 * @param {Array<Object>} array sorted
 * @param {Array<String>} sortBy keys
 * @returns {Number} index of the item in the sorted array
 */
module.exports = function getIndexForElement(element, array, sortBy) {
    /**
     *
     * @param first    element of an array
     * @param second element of an array
     * @returns {boolean} true when first should precede second
     */
    var isLowerSorted = function isLowerSorted(first, second) {
        var i = 0;
        var prop = sortBy[0];
        var firstVal;
        var secondVal;
        var accesorStrings;

        while(sortBy[i]) {
            if (prop[0] === '-') {
                prop = prop.slice(1);
                accesorStrings = prop.split('.');
                firstVal = getValueForProp(first, accesorStrings);
                secondVal = getValueForProp(second, accesorStrings);
                if (firstVal < secondVal) {
                    return false;
                }
                if (firstVal > secondVal) {
                    return true;
                } else {
                    i += 1;
                    prop = sortBy[i];
                }

            } else {
                accesorStrings = prop.split('.');
                firstVal = getValueForProp(first, accesorStrings);
                secondVal = getValueForProp(second, accesorStrings);
                if (firstVal < secondVal) {
                    return true;
                }
                if (firstVal > secondVal) {
                    return false;
                } else {
                    i += 1;
                    prop = sortBy[i];
                }
            }

        }
        return true;

    };

    var locationOf = function locationOf(element, array, start, end) {

        start = start || 0;
        end = end || array.length;
        var pivot = parseInt(start + (end - start) / 2);
//        console.log("pivot: " + pivot + ' start: ' + start + ' end: ' + end);
        if(end - start <= 1) return pivot;

        if(isLowerSorted(array[pivot], element)) {
            return locationOf(element, array, pivot, end);
        } else{
            return locationOf(element, array, start, pivot);
        }
    };

    var index = locationOf(element, array);
    if (index === 0) {
        if (array.length === 0) {
            return 0;
        }
        if(isLowerSorted(element, array[0])) {
            return 0;
        } else {
            return index + 1;
        }
    } else {
        return index + 1;
    }
};