splited big file into smaller files by functionality

gaps.go

@@ -0,0 +1,34 @@
+package interval
+
+func (intvls *intervals) HasGaps() bool {
+	intvls.Gaps()
+	if intvls.GapsList != nil && len(intvls.GapsList) > 0 {
+		return true
+	}
+	return false
+}
+
+func (intvls *intervals) Gaps() []*Interval {
+	if intvls.GapsList == nil {
+		intvls.GapsList = intvls.calculateGaps()
+	}
+	return intvls.GapsList
+}
+
+func (intvls *intervals) calculateGaps() []*Interval {
+	intvls.Sort()
+	gaps := []*Interval{}
+	lastMaxHigh := intvls.MinLow
+	for _, intvl := range intvls.Intervals {
+		if intvl.Low > lastMaxHigh {
+			gaps = append(gaps, &Interval{Low: lastMaxHigh, High: intvl.Low - 1})
+		}
+		if intvl.High >= lastMaxHigh {
+			lastMaxHigh = intvl.High + 1
+		}
+	}
+	if lastMaxHigh < intvls.MaxHigh {
+		gaps = append(gaps, &Interval{Low: lastMaxHigh, High: intvls.MaxHigh})
+	}
+	return gaps
+}