1 files changed, 69 insertions, 0 deletions
diff --git a/fs/stats.go b/fs/stats.go
new file mode 100644
index 0000000..4121ff7
--- /dev/null
+++ b/fs/stats.go
@@ -0,0 +1,69 @@
+package fs
+
+// Used to calculate how many log lines matched the regular expression
+// and how many log files could be transmitted from the server to the client.
+// Hit and transmit percentage takes only the last 100 log lines into calculation.
+type stats struct {
+	pos           int
+	lineCount     uint64
+	matched       [100]bool
+	matchCount    uint64
+	transmitted   [100]bool
+	transmitCount int
+}
+
+// Return the total line count.
+func (f *stats) totalLineCount() uint64 {
+	return f.lineCount
+}
+
+// Calculate the percentage of log lines transmitted to the client.
+func (f *stats) transmittedPerc() int {
+	return int(percentOf(float64(f.matchCount), float64(f.transmitCount)))
+}
+
+// Update bucket position. We only take into consideration the last 100
+// lines for stats.
+func (f *stats) updatePosition() {
+	f.pos = (f.pos + 1) % 100
+	f.lineCount++
+}
+
+// Increment match counter.
+func (f *stats) updateLineMatched() {
+	if !f.matched[f.pos] {
+		f.matchCount++
+		f.matched[f.pos] = true
+	}
+}
+
+// Increment transmitted counter.
+func (f *stats) updateLineTransmitted() {
+	if !f.transmitted[f.pos] {
+		f.transmitCount++
+		f.transmitted[f.pos] = true
+	}
+}
+
+// Decrement match counter.
+func (f *stats) updateLineNotMatched() {
+	if f.matched[f.pos] {
+		f.matchCount--
+		f.matched[f.pos] = false
+	}
+}
+
+// Decrement transmitted counter.
+func (f *stats) updateLineNotTransmitted() {
+	if f.transmitted[f.pos] {
+		f.transmitCount--
+		f.transmitted[f.pos] = false
+	}
+}
+
+func percentOf(total float64, value float64) float64 {
+	if total == 0 || total == value {
+		return 100
+	}
+	return value / (total / 100.0)
+}