package sparkline

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func loadGolden(t *testing.T, name string) string {
	t.Helper()
	b, err := os.ReadFile(filepath.Join("testdata", name))
	if err != nil {
		t.Fatalf("read golden %s: %v", name, err)
	}
	return strings.TrimRight(string(b), "\n")
}

func TestSparkline_Empty(t *testing.T) {
	got := strings.TrimRight(string(RenderSparkline(nil, 80, 20)), "\n")
	want := loadGolden(t, "empty.svg")
	if got != want {
		t.Errorf("empty sparkline mismatch:\nwant:\n%s\ngot:\n%s", want, got)
	}
}

func TestSparkline_SinglePoint(t *testing.T) {
	got := strings.TrimRight(string(RenderSparkline([]float64{100}, 80, 20)), "\n")
	want := loadGolden(t, "single_point.svg")
	if got != want {
		t.Errorf("single_point sparkline mismatch:\nwant:\n%s\ngot:\n%s", want, got)
	}
}

func TestSparkline_ThreePoints(t *testing.T) {
	got := strings.TrimRight(string(RenderSparkline([]float64{10, 30, 20}, 80, 20)), "\n")
	want := loadGolden(t, "three_points.svg")
	if got != want {
		t.Errorf("three_points sparkline mismatch:\nwant:\n%s\ngot:\n%s", want, got)
	}
}