go baby go

fitness-tui/internal/tui/components/chart.go

@@ -0,0 +1,92 @@
+package components
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+const (
+	BlockEmpty = " "
+	Block1     = "▁"
+	Block2     = "▂"
+	Block3     = "▃"
+	Block4     = "▄"
+	Block5     = "▅"
+	Block6     = "▆"
+	Block7     = "▇"
+	Block8     = "█"
+)
+
+var blockChars = []string{BlockEmpty, Block1, Block2, Block3, Block4, Block5, Block6, Block7, Block8}
+
+type Chart struct {
+	Width  int
+	Height int
+	Data   []float64
+	Title  string
+	style  lipgloss.Style
+}
+
+func NewChart(data []float64, width, height int, title string) *Chart {
+	return &Chart{
+		Data:   data,
+		Width:  width,
+		Height: height,
+		Title:  title,
+		style:  lipgloss.NewStyle().Padding(0, 1),
+	}
+}
+
+func (c *Chart) View() string {
+	if len(c.Data) == 0 {
+		return c.style.Render("No data available")
+	}
+
+	min, max := findMinMax(c.Data)
+	sampled := sampleData(c.Data, c.Width)
+
+	var chart strings.Builder
+	for _, value := range sampled {
+		normalized := (value - min) / (max - min)
+		level := int(normalized * 8)
+		if level > 8 {
+			level = 8
+		}
+		chart.WriteString(blockChars[level])
+	}
+
+	return c.style.Render(fmt.Sprintf("%s\n%s", c.Title, chart.String()))
+}
+
+func findMinMax(data []float64) (float64, float64) {
+	min, max := data[0], data[0]
+	for _, v := range data {
+		if v < min {
+			min = v
+		}
+		if v > max {
+			max = v
+		}
+	}
+	return min, max
+}
+
+func sampleData(data []float64, targetLength int) []float64 {
+	if len(data) <= targetLength {
+		return data
+	}
+
+	sampled := make([]float64, targetLength)
+	ratio := float64(len(data)) / float64(targetLength)
+
+	for i := 0; i < targetLength; i++ {
+		index := int(float64(i) * ratio)
+		if index >= len(data) {
+			index = len(data) - 1
+		}
+		sampled[i] = data[index]
+	}
+	return sampled
+}

fitness-tui/internal/tui/components/chart_test.go

@@ -0,0 +1,38 @@
+package components
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestChartView(t *testing.T) {
+	t.Run("empty data", func(t *testing.T) {
+		chart := NewChart(nil, 10, 4, "Test")
+		view := chart.View()
+		assert.Contains(t, view, "No data available")
+	})
+
+	t.Run("single data point", func(t *testing.T) {
+		chart := NewChart([]float64{50}, 5, 4, "Single")
+		view := chart.View()
+		assert.Equal(t, "Single\n▄▄▄▄▄", view)
+	})
+
+	t.Run("multiple data points", func(t *testing.T) {
+		data := []float64{10, 20, 30, 40, 50}
+		chart := NewChart(data, 5, 4, "Series")
+		view := chart.View()
+		assert.Equal(t, "Series\n▁▂▄▆█", view)
+	})
+
+	t.Run("downsampling", func(t *testing.T) {
+		data := make([]float64, 100)
+		for i := range data {
+			data[i] = float64(i)
+		}
+		chart := NewChart(data, 20, 4, "Downsample")
+		view := chart.View()
+		assert.Len(t, view, 20+6) // Title + chart characters
+	})
+}