Refactor display iteration/state and harden collector runtime

1 files changed, 122 insertions, 0 deletions

diff --git a/internal/display/net.go b/internal/display/net.go
new file mode 100644
index 0000000..7fc3a9d
--- /dev/null
+++ b/internal/display/net.go
@@ -0,0 +1,122 @@
+package display
+
+import (
+	"strconv"
+	"strings"
+
+	"codeberg.org/snonux/loadbars/internal/config"
+	"codeberg.org/snonux/loadbars/internal/constants"
+	"codeberg.org/snonux/loadbars/internal/stats"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+func netLinkBytesPerSec(cfg *config.Config) int64 {
+	s := strings.ToLower(strings.TrimSpace(cfg.NetLink))
+	switch s {
+	case "gbit", "1gbit":
+		return int64(constants.BytesGbit)
+	case "10gbit":
+		return int64(constants.Bytes10Gbit)
+	case "mbit", "1mbit":
+		return int64(constants.BytesMbit)
+	case "10mbit":
+		return int64(constants.Bytes10Mbit)
+	case "100mbit":
+		return int64(constants.Bytes100Mbit)
+	case "":
+		return int64(constants.BytesGbit)
+	}
+	if n, err := strconv.ParseInt(s, 10, 64); err == nil {
+		return n * int64(constants.BytesMbit)
+	}
+	return int64(constants.BytesGbit)
+}
+
+func sumNonLoNet(h *stats.HostStats) (sum stats.NetStamp, hasIface bool) {
+	if h.Net == nil {
+		return sum, false
+	}
+	for iface, ns := range h.Net {
+		if iface == "lo" {
+			continue
+		}
+		hasIface = true
+		sum.B += ns.B
+		sum.Tb += ns.Tb
+		if ns.Stamp > sum.Stamp {
+			sum.Stamp = ns.Stamp
+		}
+	}
+	return sum, hasIface
+}
+
+func drawNetBarSmoothed(renderer *sdl.Renderer, h *stats.HostStats, cfg *config.Config, smoothed *struct{ rxPct, txPct float64 }, prev stats.NetStamp, factor float64, barW int32, x, y, barH int32) stats.NetStamp {
+	renderer.SetDrawColor(constants.Black.R, constants.Black.G, constants.Black.B, 255)
+	renderer.FillRect(&sdl.Rect{X: x, Y: y, W: barW, H: barH})
+	cur, hasIface := sumNonLoNet(h)
+	if !hasIface {
+		renderer.SetDrawColor(constants.Red.R, constants.Red.G, constants.Red.B, 255)
+		renderer.FillRect(&sdl.Rect{X: x, Y: y, W: barW, H: barH})
+		return prev
+	}
+	if cur.Stamp > prev.Stamp && prev.Stamp > 0 {
+		prev = smoothNetUtilization(cur, prev, cfg, smoothed, factor)
+	} else if prev.Stamp == 0 {
+		prev = cur
+	}
+	drawNetHalves(renderer, smoothed, x, y, barW, barH)
+	return prev
+}
+
+func smoothNetUtilization(cur, prev stats.NetStamp, cfg *config.Config, smoothed *struct{ rxPct, txPct float64 }, factor float64) stats.NetStamp {
+	linkBps := netLinkBytesPerSec(cfg)
+	if linkBps <= 0 {
+		linkBps = int64(constants.BytesGbit)
+	}
+	dt := cur.Stamp - prev.Stamp
+	if dt > 0 {
+		deltaB := cur.B - prev.B
+		deltaTb := cur.Tb - prev.Tb
+		if deltaB < 0 {
+			deltaB = 0
+		}
+		if deltaTb < 0 {
+			deltaTb = 0
+		}
+		targetRx := 100 * float64(deltaB) / (float64(linkBps) * dt)
+		targetTx := 100 * float64(deltaTb) / (float64(linkBps) * dt)
+		smoothed.rxPct += (targetRx - smoothed.rxPct) * factor
+		smoothed.txPct += (targetTx - smoothed.txPct) * factor
+	}
+	return cur
+}
+
+func drawNetHalves(renderer *sdl.Renderer, smoothed *struct{ rxPct, txPct float64 }, x, y, barW, barH int32) {
+	halfW := barW / 2
+	pxPerPct := float64(barH) / 100.0
+	halfH := barH / 2
+	rxH := int32(smoothed.rxPct * pxPerPct)
+	if rxH > halfH {
+		rxH = halfH
+	}
+	if rxH > 0 {
+		renderer.SetDrawColor(constants.LightGreen.R, constants.LightGreen.G, constants.LightGreen.B, 255)
+		renderer.FillRect(&sdl.Rect{X: x, Y: y, W: halfW, H: rxH})
+	}
+	if halfW > 0 && halfH-rxH > 0 {
+		renderer.SetDrawColor(constants.Black.R, constants.Black.G, constants.Black.B, 255)
+		renderer.FillRect(&sdl.Rect{X: x, Y: y + rxH, W: halfW, H: halfH - rxH})
+	}
+	txH := int32(smoothed.txPct * pxPerPct)
+	if txH > halfH {
+		txH = halfH
+	}
+	if txH > 0 {
+		renderer.SetDrawColor(constants.LightGreen.R, constants.LightGreen.G, constants.LightGreen.B, 255)
+		renderer.FillRect(&sdl.Rect{X: x + halfW, Y: y + barH - txH, W: halfW, H: txH})
+	}
+	if halfW > 0 && (barH-txH) > 0 {
+		renderer.SetDrawColor(constants.Black.R, constants.Black.G, constants.Black.B, 255)
+		renderer.FillRect(&sdl.Rect{X: x + halfW, Y: y, W: halfW, H: barH - txH})
+	}
+}