Trading: components 161-180

level2_quotes.go

@@ -0,0 +1,123 @@
+package mujica
+
+import (
+	"fmt"
+	"log/slog"
+	"time"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
+)
+
+// L2Level is a level's price, size and order count.
+type L2Level struct {
+	Price, Size float64
+	Orders      int
+}
+
+// Level2Data holds the bid and ask levels, best first.
+type Level2Data struct {
+	Bids, Asks []L2Level
+}
+
+// Level2QuotesOptions configure a Level2Quotes.
+type Level2QuotesOptions struct {
+	// Decimals of prices and sizes; zero means 2 and 0.
+	Decimals, SizeDecimals int
+	// Levels shown each side; zero means 5.
+	Levels int
+}
+
+// level2Mark is a level's last values and size move.
+type level2Mark struct {
+	price, size float64
+	dir         int
+	at          time.Time
+	seen        bool
+}
+
+// Level2Quotes lists bid and ask levels; changes flash and mark.
+func Level2Quotes(c *ui.Context, data Level2Data, opts Level2QuotesOptions) *ui.Element {
+	dec := priceDecimals("Level2Quotes", opts.Decimals)
+	if opts.SizeDecimals < 0 || opts.Levels < 0 {
+		panic("mujica: Level2Quotes SizeDecimals and Levels cannot be negative")
+	}
+	n := opts.Levels
+	if n == 0 {
+		n = 5
+	}
+	u := Density(c).Unit()
+	e := ui.Row(c).Gap(u * 3).AlignItems(ui.Start).Role(ui.RoleTable).Label(msg(c, "level2_quotes.label"))
+	marks := ui.Local(e, "marks", func() map[string]*level2Mark { return map[string]*level2Mark{} })
+	e.Children(func() {
+		for _, side := range []OrderSide{SideBuy, SideSell} {
+			levels := data.Bids
+			if side == SideSell {
+				levels = data.Asks
+			}
+			ui.Column(c).Grow(1).Basis(0).MinWidth(0).Children(func() {
+				for i := range n {
+					var l *L2Level
+					if i < len(levels) {
+						l = &levels[i]
+					}
+					level2Row(c, *marks, side, i, l, dec, opts.SizeDecimals)
+				}
+			})
+		}
+	})
+	return e
+}
+
+// level2Row is one level with its move mark.
+func level2Row(c *ui.Context, marks map[string]*level2Mark, side OrderSide, i int, l *L2Level, dec, sizeDec int) {
+	k := Tokens(c)
+	d := Density(c)
+	name := fmt.Sprintf(msg(c, fmt.Sprintf("level2_quotes.side%d", side)), i+1)
+	key := fmt.Sprint(side, i)
+	m := marks[key]
+	if m == nil {
+		m = &level2Mark{}
+		marks[key] = m
+	}
+	row := ui.Row(c).Gap(d.Unit()*2).AlignItems(ui.Center).MinHeight(d.ControlHeight()).Padding(0, d.Unit()*2).
+		Radius(theme.ControlRadius).BorderWidth(0, 0, theme.BorderWidth, 0).BorderColor(k.Border)
+	if l == nil {
+		row.Children(func() {
+			ui.Text(c, name).TextColor(k.TextMuted).FontSize(FontSize(c, theme.CaptionSize)).Width(28)
+			ui.Text(c, "—").TextColor(k.TextMuted)
+		})
+		return
+	}
+	if m.seen && (l.Price != m.price || l.Size != m.size) {
+		// A new price is a new level, not a move.
+		m.dir, m.at = 0, c.Now()
+		if l.Price == m.price {
+			m.dir = trendSign(l.Size - m.size)
+		}
+		slog.Debug("mujica: level2_quotes level changed", "level", name)
+	}
+	m.price, m.size, m.seen = l.Price, l.Size, true
+	if dur := Motion(c, priceTextFlash); dur > 0 && !m.at.IsZero() {
+		if t := c.Now().Sub(m.at); t < dur {
+			row.Background(k.Selection.Alpha(1 - float32(float64(t)/float64(dur))))
+			c.AnimationFrame()
+		}
+	}
+	col := trendColor(c, side.sign())
+	sizeText := statisticFormat(l.Size, sizeDec)
+	orders := fmt.Sprintf(msg(c, "level2_quotes.orders"), l.Orders)
+	row.Role(ui.RoleRow).Label(name + " " + statisticFormat(l.Price, dec) + " " + sizeText + " " + orders)
+	row.Children(func() {
+		ui.Text(c, name).TextColor(k.TextMuted).FontSize(FontSize(c, theme.CaptionSize)).Width(28)
+		ui.Text(c, statisticFormat(l.Price, dec)).TextColor(col).FontFeatures("tnum").FontWeight(600).Grow(1).Basis(0).SingleLine()
+		ui.Row(c).Gap(2).AlignItems(ui.Center).Justify(ui.End).Grow(1).Basis(0).Children(func() {
+			if m.dir != 0 {
+				ui.Icon(c, trendIcon(m.dir)).Size(12, 12).TextColor(trendColor(c, m.dir))
+			}
+			ui.Text(c, sizeText).FontFeatures("tnum").SingleLine()
+		})
+		ui.Text(c, fmt.Sprint(l.Orders)).TextColor(k.TextMuted).FontFeatures("tnum").TextAlign(ui.End).Width(36).SingleLine()
+	})
+}