Restructure & refactor codebase

internal/glance/utils.go

@@ -0,0 +1,168 @@
+package glance
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"net/http"
+	"net/url"
+	"os"
+	"regexp"
+	"slices"
+	"strings"
+	"time"
+)
+
+var sequentialWhitespacePattern = regexp.MustCompile(`\s+`)
+
+func percentChange(current, previous float64) float64 {
+	return (current/previous - 1) * 100
+}
+
+func extractDomainFromUrl(u string) string {
+	if u == "" {
+		return ""
+	}
+
+	parsed, err := url.Parse(u)
+
+	if err != nil {
+		return ""
+	}
+
+	return strings.TrimPrefix(strings.ToLower(parsed.Host), "www.")
+}
+
+func svgPolylineCoordsFromYValues(width float64, height float64, values []float64) string {
+	if len(values) < 2 {
+		return ""
+	}
+
+	verticalPadding := height * 0.02
+	height -= verticalPadding * 2
+	coordinates := make([]string, len(values))
+	distanceBetweenPoints := width / float64(len(values)-1)
+	min := slices.Min(values)
+	max := slices.Max(values)
+
+	for i := range values {
+		coordinates[i] = fmt.Sprintf(
+			"%.2f,%.2f",
+			float64(i)*distanceBetweenPoints,
+			((max-values[i])/(max-min))*height+verticalPadding,
+		)
+	}
+
+	return strings.Join(coordinates, " ")
+}
+
+func maybeCopySliceWithoutZeroValues[T int | float64](values []T) []T {
+	if len(values) == 0 {
+		return values
+	}
+
+	for i := range values {
+		if values[i] != 0 {
+			continue
+		}
+
+		c := make([]T, 0, len(values)-1)
+
+		for i := range values {
+			if values[i] != 0 {
+				c = append(c, values[i])
+			}
+		}
+
+		return c
+	}
+
+	return values
+}
+
+var urlSchemePattern = regexp.MustCompile(`^[a-z]+:\/\/`)
+
+func stripURLScheme(url string) string {
+	return urlSchemePattern.ReplaceAllString(url, "")
+}
+
+func isRunningInsideDockerContainer() bool {
+	_, err := os.Stat("/.dockerenv")
+	return err == nil
+}
+
+func prefixStringLines(prefix string, s string) string {
+	lines := strings.Split(s, "\n")
+
+	for i, line := range lines {
+		lines[i] = prefix + line
+	}
+
+	return strings.Join(lines, "\n")
+}
+
+func limitStringLength(s string, max int) (string, bool) {
+	asRunes := []rune(s)
+
+	if len(asRunes) > max {
+		return string(asRunes[:max]), true
+	}
+
+	return s, false
+}
+
+func parseRFC3339Time(t string) time.Time {
+	parsed, err := time.Parse(time.RFC3339, t)
+	if err != nil {
+		return time.Now()
+	}
+
+	return parsed
+}
+
+func boolToString(b bool, trueValue, falseValue string) string {
+	if b {
+		return trueValue
+	}
+
+	return falseValue
+}
+
+func normalizeVersionFormat(version string) string {
+	version = strings.ToLower(strings.TrimSpace(version))
+
+	if len(version) > 0 && version[0] != 'v' {
+		return "v" + version
+	}
+
+	return version
+}
+
+func titleToSlug(s string) string {
+	s = strings.ToLower(s)
+	s = sequentialWhitespacePattern.ReplaceAllString(s, "-")
+	s = strings.Trim(s, "-")
+
+	return s
+}
+
+func fileServerWithCache(fs http.FileSystem, cacheDuration time.Duration) http.Handler {
+	server := http.FileServer(fs)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// TODO: fix always setting cache control even if the file doesn't exist
+		w.Header().Set("Cache-Control", fmt.Sprintf("public, max-age=%d", int(cacheDuration.Seconds())))
+		server.ServeHTTP(w, r)
+	})
+}
+
+func executeTemplateToHTML(t *template.Template, data interface{}) (template.HTML, error) {
+	var b bytes.Buffer
+
+	err := t.Execute(&b, data)
+	if err != nil {
+		return "", fmt.Errorf("executing template: %w", err)
+	}
+
+	return template.HTML(b.String()), nil
+}