1 files changed, 28 insertions, 0 deletions
diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index e70650d..c5df00d 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -1251,6 +1251,34 @@ func templateFuncMap() template.FuncMap {
 	return template.FuncMap{
 		"subtract": func(a, b int) int { return a - b },
 		"add":      func(a, b int) int { return a + b },
+		// slug turns a free-text name into an id-safe fragment, so a template
+		// can give a section a stable anchor and target it by selector. Store
+		// names are user data ("Trader Joe's", "Hardware Store") and go
+		// straight into element ids, so anything outside [a-z0-9-] has to go.
+		"slug": func(s string) string {
+			var b strings.Builder
+			lastDash := true // leading dashes are suppressed
+			for _, r := range strings.ToLower(s) {
+				switch {
+				case (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9'):
+					b.WriteRune(r)
+					lastDash = false
+				default:
+					// Collapse any run of separators/punctuation into one dash.
+					if !lastDash {
+						b.WriteByte('-')
+						lastDash = true
+					}
+				}
+			}
+			out := strings.Trim(b.String(), "-")
+			if out == "" {
+				// An empty id would make every such section share the same
+				// (invalid) anchor, so give it something addressable.
+				return "unnamed"
+			}
+			return out
+		},
 		// multiDayLabel returns the "(starts/ends HH:MM)" suffix for a
 		// multi-day calendar event's row on the day it's rendered, or ""
 		// for a normal item or a "spans" (pass-through) day, which shows