From 9e58bb41727251b77e9ff5606fe8a49fc43d8b4d Mon Sep 17 00:00:00 2001
From: "Y.Matsuda" <ymatsuda.zck@gmail.com>
Date: Sun, 31 Mar 2024 11:52:16 +0900
Subject: [PATCH] dynamic time unit support

---
 .../internal/tui/component/timeline.go        | 40 ++++++++++++---
 .../internal/tui/component/timeline_test.go   | 51 +++++++++++++++++++
 2 files changed, 84 insertions(+), 7 deletions(-)

diff --git a/tuiexporter/internal/tui/component/timeline.go b/tuiexporter/internal/tui/component/timeline.go
index 5ea510c..fdac067 100644
--- a/tuiexporter/internal/tui/component/timeline.go
+++ b/tuiexporter/internal/tui/component/timeline.go
@@ -45,10 +45,14 @@ func DrawTimeline(traceID string, cache *telemetry.TraceCache, setFocusFn func(p
 			}
 
 			// Write some text along the horizontal line.
-			durunit := duration.Milliseconds() / 10
-			tview.Print(screen, "0", x+getXByRatio(0, width), centerY, width-2, tview.AlignLeft, tcell.ColorYellow)
-			for i := 1; i < 10; i++ {
-				tview.Print(screen, fmt.Sprintf("%dms", durunit*int64(i)), x+getXByRatio(float64(i)*0.1, width), centerY, width-2, tview.AlignLeft, tcell.ColorYellow)
+			unit, count := calculateTimelineUnit(duration)
+			for i := 0; i < count; i++ {
+				ratio := float64(i) / float64(count)
+				label := roundDownDuration(unit * time.Duration(i)).String()
+				if i == 0 {
+					label = "0"
+				}
+				tview.Print(screen, label, x+getXByRatio(ratio, width), centerY, width-2, tview.AlignLeft, tcell.ColorYellow)
 			}
 
 			// Space for other content.
@@ -131,6 +135,28 @@ func DrawTimeline(traceID string, cache *telemetry.TraceCache, setFocusFn func(p
 	}
 }
 
+func calculateTimelineUnit(duration time.Duration) (unit time.Duration, count int) {
+	// TODO: set count depends on the width
+	count = 5
+	unit = duration / time.Duration(count)
+	return
+}
+
+func roundDownDuration(d time.Duration) time.Duration {
+	if d < time.Microsecond {
+		return d - (d % time.Nanosecond)
+	} else if d < time.Millisecond {
+		return d - (d % time.Microsecond)
+	} else if d < time.Second {
+		return d - (d % time.Millisecond)
+	} else if d < time.Minute {
+		return d - (d % time.Second)
+	} else if d < time.Hour {
+		return d - (d % time.Minute)
+	}
+	return d
+}
+
 func placeSpan(grid *tview.Grid, node *spanTreeNode, row, depth int, tvs *[]*tview.TextView, nodes *[]*spanTreeNode) int {
 	row++
 	label := node.label
@@ -181,8 +207,8 @@ func newSpanTree(traceID string, cache *telemetry.TraceCache) (rootNodes []*span
 		node := nodes[spanMemo[current]]
 		st, en := span.Span.StartTimestamp().AsTime().Sub(start), span.Span.EndTimestamp().AsTime().Sub(start)
 		d := en - st
-		node.box = createSpan(current, int(duration.Milliseconds()), int(st.Milliseconds()), int(en.Milliseconds()))
-		node.label = fmt.Sprintf("%s %dms", span.Span.Name(), d.Milliseconds())
+		node.box = createSpan(current, duration, st, en)
+		node.label = fmt.Sprintf("%s %s", span.Span.Name(), d.String())
 
 		parent := span.Span.ParentSpanID().String()
 		_, parentExists := cache.GetSpanByID(parent)
@@ -224,7 +250,7 @@ func getXByRatio(ratio float64, width int) int {
 	return int(float64(width) * ratio)
 }
 
-func createSpan(name string, total, start, end int) (span *tview.Box) {
+func createSpan(name string, total, start, end time.Duration) (span *tview.Box) {
 	return tview.NewBox().SetBorder(false).
 		SetDrawFunc(func(screen tcell.Screen, x, y, width, height int) (int, int, int, int) {
 			// Draw a horizontal line across the middle of the box.
diff --git a/tuiexporter/internal/tui/component/timeline_test.go b/tuiexporter/internal/tui/component/timeline_test.go
index 84ea673..1e6c259 100644
--- a/tuiexporter/internal/tui/component/timeline_test.go
+++ b/tuiexporter/internal/tui/component/timeline_test.go
@@ -52,3 +52,54 @@ func TestNewSpanTree(t *testing.T) {
 	assert.Equal(t, sds[4].Span, st[1].span.Span)
 	assert.Equal(t, sds[5].Span, st[1].children[0].span.Span)
 }
+
+func TestRoundDownDuration(t *testing.T) {
+	tests := []struct {
+		name     string
+		duration time.Duration
+		want     string
+	}{
+		{
+			name:     "0",
+			duration: 0,
+			want:     "0s", // do nothing
+		},
+		{
+			name:     "10 nano second",
+			duration: 10 * time.Nanosecond,
+			want:     "10ns", // do nothing
+		},
+		{
+			name:     "10.25 micro second",
+			duration: 10250 * time.Nanosecond,
+			want:     "10µs",
+		},
+		{
+			name:     "10.25 milli second",
+			duration: 10250 * time.Microsecond,
+			want:     "10ms",
+		},
+		{
+			name:     "10.25 second",
+			duration: 10250 * time.Millisecond,
+			want:     "10s",
+		},
+		{
+			name:     "10.25 minute",
+			duration: 615 * time.Second,
+			want:     "10m0s",
+		},
+		{
+			name:     "10.25 hour",
+			duration: 615 * time.Minute,
+			want:     "10h15m0s", // do nothing
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := roundDownDuration(tt.duration)
+			assert.Equal(t, tt.want, got.String())
+		})
+	}
+}