private void addToSet()

in x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/scheduler/Cron.java [1224:1346]
106 lines of code
70 McCabe index (conditional complexity)

    private void addToSet(int val, int end, int incr, int type) throws ElasticsearchParseException {

        TreeSet<Integer> set = getSet(type);

        if (type == SECOND || type == MINUTE) {
            if ((val < 0 || val > 59 || end > 59) && (val != ALL_SPEC_INT)) {
                throw illegalArgument("Minute and Second values must be between 0 and 59");
            }
        } else if (type == HOUR) {
            if ((val < 0 || val > 23 || end > 23) && (val != ALL_SPEC_INT)) {
                throw illegalArgument("Hour values must be between 0 and 23");
            }
        } else if (type == DAY_OF_MONTH) {
            if ((val < 1 || val > 31 || end > 31) && (val != ALL_SPEC_INT) && (val != NO_SPEC_INT)) {
                throw illegalArgument("Day of month values must be between 1 and 31");
            }
        } else if (type == MONTH) {
            if ((val < 1 || val > 12 || end > 12) && (val != ALL_SPEC_INT)) {
                throw illegalArgument("Month values must be between 1 and 12");
            }
        } else if (type == DAY_OF_WEEK) {
            if ((val == 0 || val > 7 || end > 7) && (val != ALL_SPEC_INT) && (val != NO_SPEC_INT)) {
                throw illegalArgument("Day-of-Week values must be between 1 and 7");
            }
        }

        if ((incr == 0 || incr == -1) && val != ALL_SPEC_INT) {
            if (val != -1) {
                set.add(val);
            } else {
                set.add(NO_SPEC);
            }

            return;
        }

        int startAt = val;
        int stopAt = end;

        if (val == ALL_SPEC_INT && incr <= 0) {
            incr = 1;
            set.add(ALL_SPEC); // put in a marker, but also fill values
        }

        if (type == SECOND || type == MINUTE) {
            if (stopAt == -1) {
                stopAt = 59;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 0;
            }
        } else if (type == HOUR) {
            if (stopAt == -1) {
                stopAt = 23;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 0;
            }
        } else if (type == DAY_OF_MONTH) {
            if (stopAt == -1) {
                stopAt = 31;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 1;
            }
        } else if (type == MONTH) {
            if (stopAt == -1) {
                stopAt = 12;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 1;
            }
        } else if (type == DAY_OF_WEEK) {
            if (stopAt == -1) {
                stopAt = 7;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 1;
            }
        } else if (type == YEAR) {
            if (stopAt == -1) {
                stopAt = MAX_YEAR;
            }
            if (startAt == -1 || startAt == ALL_SPEC_INT) {
                startAt = 1970;
            }
        }

        // if the end of the range is before the start, then we need to overflow into
        // the next day, month etc. This is done by adding the maximum amount for that
        // type, and using modulus max to determine the value being added.
        int max = -1;
        if (stopAt < startAt) {
            max = switch (type) {
                case SECOND -> 60;
                case MINUTE -> 60;
                case HOUR -> 24;
                case MONTH -> 12;
                case DAY_OF_WEEK -> 7;
                case DAY_OF_MONTH -> 31;
                case YEAR -> throw new IllegalArgumentException("Start year must be less than stop year");
                default -> throw new IllegalArgumentException("Unexpected type encountered");
            };
            stopAt += max;
        }

        for (int i = startAt; i <= stopAt; i += incr) {
            if (max == -1) {
                // ie: there's no max to overflow over
                set.add(i);
            } else {
                // take the modulus to get the real value
                int i2 = i % max;

                // 1-indexed ranges should not include 0, and should include their max
                if (i2 == 0 && (type == MONTH || type == DAY_OF_WEEK || type == DAY_OF_MONTH)) {
                    i2 = max;
                }

                set.add(i2);
            }
        }
    }