1var isSymbol = require('./isSymbol');
2
3/** Used as references for the maximum length and index of an array. */
4var MAX_ARRAY_LENGTH = 4294967295,
5    MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1;
6
7/* Built-in method references for those with the same name as other `lodash` methods. */
8var nativeFloor = Math.floor,
9    nativeMin = Math.min;
10
11/**
12 * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy`
13 * which invokes `iteratee` for `value` and each element of `array` to compute
14 * their sort ranking. The iteratee is invoked with one argument; (value).
15 *
16 * @private
17 * @param {Array} array The sorted array to inspect.
18 * @param {*} value The value to evaluate.
19 * @param {Function} iteratee The iteratee invoked per element.
20 * @param {boolean} [retHighest] Specify returning the highest qualified index.
21 * @returns {number} Returns the index at which `value` should be inserted
22 *  into `array`.
23 */
24function baseSortedIndexBy(array, value, iteratee, retHighest) {
25  var low = 0,
26      high = array == null ? 0 : array.length;
27  if (high === 0) {
28    return 0;
29  }
30
31  value = iteratee(value);
32  var valIsNaN = value !== value,
33      valIsNull = value === null,
34      valIsSymbol = isSymbol(value),
35      valIsUndefined = value === undefined;
36
37  while (low < high) {
38    var mid = nativeFloor((low + high) / 2),
39        computed = iteratee(array[mid]),
40        othIsDefined = computed !== undefined,
41        othIsNull = computed === null,
42        othIsReflexive = computed === computed,
43        othIsSymbol = isSymbol(computed);
44
45    if (valIsNaN) {
46      var setLow = retHighest || othIsReflexive;
47    } else if (valIsUndefined) {
48      setLow = othIsReflexive && (retHighest || othIsDefined);
49    } else if (valIsNull) {
50      setLow = othIsReflexive && othIsDefined && (retHighest || !othIsNull);
51    } else if (valIsSymbol) {
52      setLow = othIsReflexive && othIsDefined && !othIsNull && (retHighest || !othIsSymbol);
53    } else if (othIsNull || othIsSymbol) {
54      setLow = false;
55    } else {
56      setLow = retHighest ? (computed <= value) : (computed < value);
57    }
58    if (setLow) {
59      low = mid + 1;
60    } else {
61      high = mid;
62    }
63  }
64  return nativeMin(high, MAX_ARRAY_INDEX);
65}
66
67module.exports = baseSortedIndexBy;
68